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The field of supported catalysis has experienced increased attention with respect to the development of novel architectures for immobilizing catalytic species, aiming to maintain or enhance their activity while facilitating the easy recovery and reuse of the active moiety. Dendrimers have been identified as promising candidates capable of imparting such properties to catalysts through selective functionalization. The present study details the synthesis of two polyphosphorhydrazone (PPH) dendrons, each incorporating azide or acetylene groups at the core for subsequent coupling through "click" triazole chemistry. Employing this methodology, a novel PPH Janus dendrimer was successfully synthesized, featuring ten polyethylene glycol (PEG) chains on one side of the structure and ten Ru(p-cymene) derivatives on the other. This design was intended to confer dual properties, influencing solubility modulation, and allowing the presence of active catalytic moieties. The synthesized dendrimer underwent testing in the isomerization of allyl alcohols in organic solvents and biphasic solvent mixtures. The results demonstrated a positive dendritic effect compared with model monometallic and bimetallic species, providing a proof-ofconcept for the first PPH Janus dendrimer with tested applications in catalysis. [ABSTRACT FROM AUTHOR]

Over the past few years, eutectic solvents (ESs) have drawn the scientific community's attention because they are usually more environmentally friendly than traditional organic solvents. One of the applications of ESs is in the gas capture field, where they are considered promising absorbers to replace amine- (MEA, DEA, or MDEA processes), methanol- (Rectisol process), dimethyl ethers of polyethylene glycol- (Selexol process), N-methyl-2-pyrrolidone- (Purisol process), propylene carbonate- (Fluor solvent process), or morpholine-based (Morphysorb process) solvents on CO2 capture from the atmosphere. Although several studies have reported experimental gas solubility data in ESs, especially for CO2, only a few existing options are covered. In fact, resorting to experimental methods to obtain the solubility data seems unfeasible considering the vast number of possible eutectic mixtures. Therewith, theoretical predictions of gas solubility in ESs are valuable for the fast pre-screening of prospective solvents. In this work, the ability of the thermodynamic model COSMO-RS to represent solubility data of CO2, CH4, and H2S in 17 choline chloride-based (ChCl) ESs was evaluated. The experimental data were collected from the literature at different molar ratios, at 298.15 K or 313.15 K, and in the pressure range from 1 to 125 bar. COSMO-RS offers a qualitative description of these gases' solubility, which was expected due to the model's fully predictive character. To improve the CO2 and CH4 solubility data description, a temperature–pressure-dependent correction was applied to the COSMO-RS predictions for these gases, offering a global average relative deviation of 15%. [ABSTRACT FROM AUTHOR]

A spectroscopic method of chemical analysis is used to determine the mole fraction solubilities of 3,5-dimethoxybenzoic acid dissolved in propanenitrile, in eleven additional alkanol solvents (1-pentanol, 1-hexanol, 1-heptanol, 1-octanol, 2-methyl-1-propanol, 2-pentanol, 2-methyl-1-butanol, 3-methyl-1-butanol, 4-methyl-2-pentanol, 2-ethyl-1-hexanol, cyclopentanol) and in three additional alkyl alkanoate solvents (isopropyl acetate, tert-butyl acetate, methyl butyrate) at 298.15 K. Results from our experimental measurements, combined with published partition coefficient and solubility data, are used to calculate the Abraham model solute descriptors of the monomeric form of 3,5-dimethoxybenzoic acid. In total 62 experimental data points were used in the computation. The calculated solute descriptors describe the experimental solubility and partition coefficient data to within an overall standard deviation of 0.064 log units. [ABSTRACT FROM AUTHOR]

Mole fraction solubilities have been experimentally determined for 2,3-dimethoxybenzoic acid dissolved in propanenitrile and diisopropyl ether, in two more alkyl alkanoates (tert-butyl acetate, methyl butanoate), and in ten more alcohols (1-pentanol, 1-hexanol, 1-heptanol, 1-octanol, 2-methyl-1-propanol, 2-butanol, 2-pentanol, 3-methyl-1-butanol, 4-methyl-2-pentanol, cyclopentanol) at 298.15 K using a spectrophotometric method of chemical analysis based on the Beer-Lambert law. Experiment-based solute descriptors for the monomeric form of the dissolved carboxylic acid solute have been calculated using the results from our solubility measurements, combined with published solubility data taken from the chemical literature. The calculated solute descriptors provide a reasonably accurate mathematical description of the observed solubility data, with the overall standard deviation between the observed and back-calculated values being 0.074 log units. The solute descriptors further suggest that the carboxylic acid solute does not undergo intramolecular hydrogen bonding in the 28 organic solvents considered in the current study. [ABSTRACT FROM AUTHOR]

Background: Naringin is one of the main flavonoids in citrus fruits and byproducts. This flavanone has been shown to be a good antioxidant nutraceutical component, and it also has potential as a gut microbiome modulator, although its applications in final formulations represent a challenge due to its low solubility, both in water and in organic solvents. This work addresses this problem by functionalizing naringin through enzymatic acylation. Results: The enzymatic acylation catalyzed by the lipase Novozym® 435 and using acyl donors of different chain lengths, acetate (C2), propionate (C3), and laurate (C12), yielded in conversions of 95% at 24 h and 100% at 48 h, generating a monoacylated product. Both the aqueous and solvent solubility of acylated naringin products were improved while maintaining or even increasing their antioxidant activity. Conclusions: This acylation process significantly enhanced both the water and solvent solubility of the acylated naringin products while preserving or even enhancing their antioxidant activity. In addition to the gut-modulating properties of flavonoids, acylating them with short- and medium-chain fatty acids could enhance their potential applications in the emerging field of research dedicated to understanding and modulating gut health. [ABSTRACT FROM AUTHOR]

Conjugated polymers (CPs) having a backbone of alternating single and multiple bonds are well known for their technological applications. Herein, we report the successful synthesis of CPs; poly(o-chloroaniline) (POCA), poly(o-phenylenediamine) (POPD), and for the first time their copolymer poly(OPD-co-OCA) along with the evaluation of corrosion inhibition efficiency. The obtained materials were characterized by UV–Visible spectroscopy, FTIR, SEM, XRD, TGA, and cyclic voltammetry measurements. The comparative analysis confirmed the satisfactory formation of homopolymers POCA, POPD and its copolymer poly(OPD-co-OCA). The homopolymer POPD and copolymer poly(OPD-co-OCA) are soluble in common organic solvents (acetone, methanol, N-methyl-2-pyrrolidone (NMP), Dimethyl sulfoxide (DMSO), and chloroform) while homopolymer POCA is insoluble. The novel copolymer poly(OPD-co-OCA) reveals good thermal stability than homopolymers POPD and POCA. The cyclic voltammetry studies show that copolymer poly(OPD-co-OCA) acquired redox behavior having an anodic peak at about 0.4 V, nevertheless corresponding homopolymer POPD act as an insulator with no obvious redox peak. The corrosion inhibition efficiency on a mild steel for copolymer poly(OPD-co-OCA) is found 70 to 80% which is reasonably higher than homopolymer POPD (68%), probably is due to donor–acceptor substituents involved in copolymer. [ABSTRACT FROM AUTHOR]

A series of [PcMnL2]SbF6 complexes (Pc = phthalocyanine) was synthesized and structurally characterized by stripping the chloride from PcMnCl with AgSbF6 in o-dichlorobenzene and adding a range of donor ligands (L = THF, pyridine, p-dimethylaminopyridine (DMAP), Ph3PO, N-methylimidazole (MeIm), MeCN) to the resulting solution. Addition of or exposure to water where L = heterocyclic amines yielded μ-oxo complexes of the form [PcMnL]2O, which were structurally characterized for L = DMAP and MeIm. The [PcMnL2]SbF6 complexes have an increased solubility in organic solvents, where the axial ligands inhibit the characteristic ring π−π aggregation of PcM complexes. A variety of colours were observed (blue/green to red/purple), with Q-band absorptions (excluding the μ-oxo species) spanning from 715–761 nm and LMCT-bands from 497–574 nm. The combination of the ligand-induced absorption shifts coupled with their relative intensities in the visible region is responsible for the observed colour range and illustrates that facile ligand exchange is a useful tool in producing materials with a variety of colours from PcMnCl. [ABSTRACT FROM AUTHOR]

In this research, a new Lewis acid-based deep eutectic solvent (LA-DES) was synthesized using diphenhydramine hydrochloride and CoCl2·6H2O, (2[HDPH]:CoCl42−), and identified by FT-IR and 1HNMR techniques. The physicochemical properties of this LA-DES, such as thermal behavior, thermal stability, and solubility in common solvents were also investigated. The catalytic ability of 2[HDPH]:CoCl42− was ascertained in the efficient synthesis of a novel array of thiadiazolo[2,3-b]quinazolin-6-one scaffolds via a one-pot three-component reaction of dimedone/1,3-cyclohexanedione, aldehydes, and 5-aryl-1,3,4-thiadiazol-2-amines/3-(5-amino-1,3,4-thiadiazol-2-yl)-2H-chromen-2-one under solvent-free conditions. This catalyst was also successfully utilized for the synthesis of mono- and bis-thiadiazolo[2,3-b]quinazolin-6-ones from dialdehydes or bis-1,3,4-thiadiazol-2-amine. The simplicity of enforcement, short reaction time, avoidance of toxic organic solvents, scalability of the synthesis procedure, excellent atom economy, high reaction mass efficiency, and low E-factor are other outstanding advantages of this newly developed method. Furthermore, due to the convenient recovery and reuse of LA-DES, this protocol is economically justified and environmentally friendly. [ABSTRACT FROM AUTHOR]

We used the extreme gradient boosting (XGB) algorithm to predict the experimental solubility of chemical compounds in water and organic solvents and to select significant molecular descriptors. The accuracy of prediction of our forward stepwise top-importance XGB (FSTI-XGB) on curated solubility data sets in terms of RMSE was found to be 0.59–0.76 Log(S) for two water data sets, while for organic solvent data sets it was 0.69–0.79 Log(S) for the Methanol data set, 0.65–0.79 for the Ethanol data set, and 0.62–0.70 Log(S) for the Acetone data set. That was the first step. In the second step, we used uncurated and curated AquaSolDB data sets for applicability domain (AD) tests of Drugbank, PubChem, and COCONUT databases and determined that more than 95% of studied ca. 500,000 compounds were within the AD. In the third step, we applied conformal prediction to obtain narrow prediction intervals and we successfully validated them using test sets' true solubility values. With prediction intervals obtained in the last fourth step, we were able to estimate individual error margins and the accuracy class of the solubility prediction for molecules within the AD of three public databases. All that was possible without the knowledge of experimental database solubilities. We find these four steps novel because usually, solubility-related works only study the first step or the first two steps. [ABSTRACT FROM AUTHOR]

A library of cyclometallated iridium(III) complexes with a strong H-bonding motif in their ancillary ligand was synthesized, characterized and their photophysical properties measured. Demonstrated herein is a general synthetic high yield procedure for these compounds. We ascribe these yields to the use of an intermediary primer ligand. This de novo strategy circumnavigates the standard synthetic issues of H-bond rich ligand precursors (self-aggregation and poor solubility in organic solvents). [ABSTRACT FROM AUTHOR]

In this study, we prepared amine‐functionalized fullerene derivatives by using methylene blue (MB)‐sensitized photoaddition reactions of fullerene C60 with a variety of α‐silyl group containing N‐alkylglycinates through 1,3‐dipolar cycloaddition reactions of in situ formed azomethine ylide, derived from glycinates, to fullerene C60 and examined their solubility properties in several organic solvents. The results showed that although it was hard to find a clear correlation between the solvent solubility of and N‐substituents of fullereopyrrolidines, the solubility of functionalized fullerene derivatives in organic solvents such as toluene, CHCl3, CH2Cl2, and tetrahydrofuran (THF) was much higher than that of C60 and in addition, the solubility properties of fullereopyrrolidines can be manipulated by incorporating diverse organic moieties into fullerene surface. [ABSTRACT FROM AUTHOR]

Extraction of As(III) from hydrochloric acid solution using various solvents on the basis of ion solvation has been reported, but a theoretical framework to describe the suitability of solvents for extraction has not been systematized. In this study, comprehensive extraction tests for As(III) using a variety of organic solvents were conducted to clarify the requirements for solvents to extract As(III). From the results of initial screening tests, various aromatics, ethers, and ketones were rated as candidates for the extraction of As(III) at high HCl concentrations, whereas aliphatic hydrocarbons were excluded. Many solvents showed high extraction capacity for As(III) to give organic fraction concentrations of 150 mM or higher. The logP value (P = partitioning coefficient between n-octanol and water) within a solvent class showed some correlation with extractability of As(III) but the correlation was invalid across solvent types. High correlation was shown between the Hansen solubility parameters of the solvents and As(III) extractability: Twenty of 22 solvents (90.9%) were appropriately classified as valid or invalid for the extraction of As(III) based on the Hansen sphere. 2-Nonanone was recommended as an ideal solvent for As(III) extraction because of its good balance between high extractability and its desirable physical properties for industrial operations. As(III) was quantitatively stripped from 2-nonanone into water with a concentration factor of 22.6. [ABSTRACT FROM AUTHOR]

Chitosan (CS) has long been regarded as a substance with numerous exceptional qualities, including biodegradability, biocompatibility, non-toxicity, and ecological sustainability. However, its widespread use is hampered by its weak solubility in water and in typical organic solvents. This limits its applications in biomedical and other areas. Chemical modification of chitosan improves its solubility in aqueous solutions. The use of carboxymethyl moieties to chemically modify the hydroxyl and amino groups already present on the CS chains would increase the solubility of chitosan and also endow it with a variety of special chemical, physical, and biological properties. The water solubility, antibacterial, absorption/retention, and emulsion stabilizing properties of the carboxymethyl chitosan (CMC) compounds have all been improved. They can engage with cells to promote cell proliferation, regeneration, and wound healing. So, this review will focus on different derivatives of CMC with special emphasis on their preparative methods. [ABSTRACT FROM AUTHOR]

Taxanes are a class of potent anticancer agents used in different cancers. Their low water solubility is the major challenge in formulation development that leads to the use of surfactants and organic solvents which causes severe hypersensitivity reactions. In this study, paclitaxel (PTX) was conjugated to a water-soluble and biocompatible polymer, dextran, to enhance solubility. Levothyroxine was also conjugated to dextran to provide targeted delivery. The cytotoxicity was studied on HepG2 and A375 cell lines before and after treating cell lines with levothyroxine. Results showed approximately 1250-fold water solubility enhancement by dextran conjugation. Drug conjugates presented higher cytotoxicity on A375 cell lines than its free drug counterparts at 10 and 50 nM concentrations after 24 hours. Pre-treatment with levothyroxine decreased the cytotoxicity on A375 as an integrin receptor rich cell line but did not show any significant effect on HepG2 cells which is low in expressing integrin receptor. In conclusion, preparation of levothyroxine targeted dextran conjugate might be an effective strategy for PTX delivery to different cell lines. [ABSTRACT FROM AUTHOR]

Dasatinib is an aminopyrimidine used as an inhibitor of multiple tyrosine kinases in two different formulations an immediate-release tablet and a powder for oral suspension. It shows a very low pH-dependent solubility in aqueous solutions and higher solubility in organic solvents. The solubility plays an essential role in analytical methodology to establish the purity, potency, safety and efficacy of any drug product as a diluent. Also, extraction of active drug substance with a suitable diluent from matrix composition is crucial for any analytical method development. However, a diluent optimization study during the method development of related substances for the drug product reveals that the Piperazine ring presented in Dasatinib is susceptible to oxidation and forms an N-oxide impurity. The impurity formation is due to the micro oxidic properties of the solvent used as a diluent which is inducing an oxidation reaction. Therefore, a comprehensive investigative study was conducted to optimize the diluent by limiting N-Oxide generation. [ABSTRACT FROM AUTHOR]

In this paper, structural modification of benzoylurea compound NK-17, which has been reported to have excellent insecticidal activity, resulted in the compound (E)-N-((4-((tertbutoxyimino)methyl)phenyl)(methyl)carbamoyl)-2,6-difluoro benzamide (hereinafter referred to as HN21)to improve its solubility in organic solvents. The leaf film method was used to determine the bioactivity of lufenuron and HN-21 against the second instar larvae of Spodoptera frugiperda, and their effects on the chitin synthesis process were also analyzed. The results showed that the median lethal concentration (LC50) of HN-21 for 72 h was 0.681 mg/L, significantly lower than that of the positive control lufenuron (10.052 mg/L), and all the abnormal larvae died during molting. Compared to the control group, the expression of chitin synthesis pathway genes (sfTRE1, sfTRE2, sfGFAT, sfUAP, sfCHS1) decreased significantly after 24 h of lufenuron treatment at the concentration of 10.052 mg/L, earlier than HN-21 treatment at the concentration of 0.681 mg/L, but there was no significant difference between the two groups after 48 h treatment. These results can provide a theoretical basis for the development and utilization of benzoylurea compounds. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) have been extensively used in drug formulation and delivery as designer solvents and other components because of their inherent tunability and useful physicochemical and biopharmaceutical properties. ILs can be used to manage some of the operational and functional challenges of drug delivery, including drug solubility, permeability, formulation instability, and in vivo systemic toxicity, that are associated with conventional organic solvents/agents. Furthermore, ILs have been recognized as potential solvents to address the polymorphism, limited solubility, poor permeability, instability, and low bioavailability of crystalline drugs. In this account, we discuss the technological progress and strategies toward designing biocompatible ILs and explore potential biomedical applications, namely the solubilization of small and macromolecular drugs, the creation of active pharmaceutical ingredients, and the delivery of pharmaceuticals. [ABSTRACT FROM AUTHOR]

In this work, the mutual solubilities of sets of organic diluents (CHCl3, C6H6, C2H4Cl2, CCl4, C6H12, and n-hexane) with the organic compound ethylene glycol are investigated via gas chromatography (GC). The experimental data measured for these binary organic systems are used to adjust the future nonaqueous systems for the solvent extraction of various metals with ligands. The obtained results showed that the solubility of ethylene glycol decreased in the order CHCl3 > C6H6 > C2H4Cl2 > CCl4(0%) ≈ C6H12 ≈ n-hexane. On the other hand, the solubility of the tested traditional organic diluents in ethylene glycol decreased in the following order: C6H6 > CHCl3 > C2H4Cl2 > n-hexane > C6H12 > CCl4. 1H NMR was also used as an analytic method in order to compare the obtained results for the samples showing significant solubility only, including an additional study with 1,2- or 1,3-propanediol. The enhanced solubility of the C6H6 compound in ethylene glycol was identified here as critical due to the GC technique, which will be without future consequences in chemical technology. Therefore, it was found that the best molecular diluent for the recovery of metals among the tested ones is C6H12, with a green protocol as the new paradigm, replacing the aqueous phase with another nonaqueous phase, i.e., a second organic diluent. [ABSTRACT FROM AUTHOR]

A proline-based, chiral bi-functional organocatalyst containing both pyrrolidine and oxadiazolone heterocycle, has been successfully applied for stereoselective aldol reactions. The replacement of polar -COOH group of proline with bioisostere oxadiazolone ring provides excellent solubility of this catalyst in various organic solvents compared to low soluble proline. As a result, the organocatalyst effectively catalyzed the asymmetric condensation reaction between differently substituted aromatic aldehydes and various symmetrical and unsymmetrical ketones to produce the corresponding aldol products with excellent stereoselectivities (dr: 97:3, ee >99.9%) at room temperature in open-air. [ABSTRACT FROM AUTHOR]

Methods are examined for estimating the Hildebrand solubility parameter of a mixture of organic solvents using the characteristics of their structural elements. A procedure is proposed for calculating the solubility parameter for mixtures of solvents differing in composition and structure depending on the ratio of their components. These results enable us to predict the optimal solvent mixture composition for polymers with a known Hildebrand solubility parameter. The proposed method permits us to estimate the solubility of complex mixtures of hydrocarbons of petroleum origin such as the tar obtained as the vacuum residue of oil distillation when it is used as a polymer solvent. 1H NMR analysis results were used to determine the structural elements of a tar and calculate its Hildebrand solubility parameter. [ABSTRACT FROM AUTHOR]

The cholesterol-functionalized polycarbonate-based diblock copolymer, PEG113-b-P(MTC-Chol)30, forms pathway-dependent nanostructures via dialysis-based solvent exchange. The initial organic solvent that dissolves or disperses the polymer dictates a self-assembly pathway. Depending upon the initial solvent, nanostructures of disk-like micelles, exhibiting asymmetric growth and hierarchical features, are accessible from a single amphiphilic precursor. Dioxane and tetrahydrofuran (THF) molecularly dissolve the block copolymer, but THF yields disks, while dioxane yields stacked disks after dialysis against water. Dimethylformamide and methanol display dispersed disks and then form stacked disk structures after dialysis. The path-dependent morphology was correlated to solubility parameters, an understanding of which offers routes to tailor self-assemblies with limited sets of building blocks. [ABSTRACT FROM AUTHOR]

The aim of this study is to correlate the solubility and electrospinnability of gelatin in different organic solvent systems. Teas graph was employed using the Hansen parameters in this systematic study to map the solvents that dissolve and enable the electrospinning of gelatin. It was found that in some cases, the solvent dissolved gelatin but the solution was not spinnable. Increasing the hydrogen bonding force (fh) assisted in the electrospinning of the gelatin solution. Higher dispersion force (fd) improves the electrospinnability at lower concentration of gelatin. The viscosity of the solution of pure acetic acid (AA) is higher than the binary solution of 3:1 AA/water and 3:1 AA/tetrahydrofuran (THF) for the same concentration of gelatin; the higher viscosity enhanced the electrospinning properties. Interestingly, field-emission scanning electron microscopy arrayed that the effect of increasing the concentration of gelatin in the pure AA system resulted in the formation of thicker fibres, however, it induced the formation of uniform fibres in the 3:1 AA/water system, whereas beaded morphology was obtained when lower concentration of gelatin was used. The fibres obtained from electrospinning the solution of 3:1 AA/THF resulted in the formation of thicker and non-uniform fibres due to the low electrical conductivity as well as the high volatility of the solution. Attenuated total reflectance-Fourier transform infrared spectroscopy portrayed all the major peaks of gelatin in the electrospun fibres. However, widening of the Amide-A peak of gelatin was observed when the solvent system of formic acid and 3:1 AA/THF were used. Thermal study of the fibre mats depicts that the binary solvent system using AA is more suitable to obtain nanofibres with more analogous structure to pristine gelatin. The electrospun samples of gelatin in the different solvent systems did not exhibit any cytotoxity on the HeLa cell line. Teas graph can be used as a quick solvent selection tool to prepare electrospinning solutions of gelatin blended with synthetic polymers to obtain nanofibres for biomedical applications. [ABSTRACT FROM AUTHOR]

This work investigates the support of organocatalysts in polyesters, a class of polymers seldom used for this purpose. The proposal is to use the hydroxyl groups present in the structure of the chosen chiral compounds to promote the polymerization of ε-caprolactone, generating the support and anchoring the organocatalyst in a single step. A very simple method, with acid catalysis, was employed, that showed versatility in generating supported catalysts with different structures and functional groups and modulating the mass of the materials to generate specific solubility characteristics. In this way, the catalysts can be solubilized in some organic solvents, such as dichloromethane, but at the end of the reaction, they can be recovered in a heterogeneous way, through precipitation in more apolar solvents. The materials were applied as organocatalysts on an aldol addition test reaction and the product could be obtained in excellent yields and good stereoselectivity. The polymer did not show signs of degradation after the reaction, proving to be robust and suitable for use in catalysis; however, a recycling process appears to be necessary for its reuse. [ABSTRACT FROM AUTHOR]

Abraham model solute descriptors are determined for vanillin and five select derivatives (o-vanillin, isovanillin, vanillic acid, vanillyl alcohol and ethylvanillin) based on experimental solubility and partition coefficient data that we were able to find in the published literature. The solute descriptor values reported in the current communication back-calculate the observed experimental data to within standard errors of 0.12 log units (or less). The calculated solute descriptors can be used to predict the solubility of the vanillin and the five select derivatives in additional organic mono-solvents and binary aqueous-ethanol solvent mixtures using published Abraham model correlations. [ABSTRACT FROM AUTHOR]

The solubility of active pharmaceutical ingredients is a mandatory physicochemical characteristic in pharmaceutical practice. However, the number of potential solvents and their mixtures prevents direct measurements of all possible combinations for finding environmentally friendly, operational and cost-effective solubilizers. That is why support from theoretical screening seems to be valuable. Here, a collection of acetaminophen and phenacetin solubility data in neat and binary solvent mixtures was used for the development of a nonlinear deep machine learning model using new intuitive molecular descriptors derived from COSMO-RS computations. The literature dataset was augmented with results of new measurements in aqueous binary mixtures of 4-formylmorpholine, DMSO and DMF. The solubility values back-computed with the developed ensemble of neural networks are in perfect agreement with the experimental data, which enables the extensive screening of many combinations of solvents not studied experimentally within the applicability domain of the trained model. The final predictions were presented not only in the form of the set of optimal hyperparameters but also in a more intuitive way by the set of parameters of the Jouyban–Acree equation often used in the co-solvency domain. This new and effective approach is easily extendible to other systems, enabling the fast and reliable selection of candidates for new solvents and directing the experimental solubility screening of active pharmaceutical ingredients. [ABSTRACT FROM AUTHOR]

In this research, we studied, in detail, the behavior of common PNIPAM microgels, obtained through surfactant-free precipitation polymerization, in a number of organic solvents. We showed that many of the selected solvents serve as good solvents for the PNIPAM microgels and that the size and architecture of the microgels depend on the solvent chosen. Expanding the range of solvents used for PNIPAM microgel incubation greatly enhances the possible routes for microparticle functionalization and modification, as well as the encapsulation of water-insoluble species. In this demonstration, we successfully encapsulated water-insoluble Sudan III dye in PNIPAM microgels and prepared the aqueous dispersions of such composite-colored microparticles. [ABSTRACT FROM AUTHOR]

AB-polybenzimidazole (ABPBI) dissolution kinetics in an eco-friendly complex acid-free solvent based on dimethyl sulfoxide (DMSO), methanol and KOH, and the rheological behavior of their solutions are investigated. The optimal component ratio of solvent providing the complete ABPBI dissolution is determined. Methanol containing dissolved KOH contributes to the creation of a single-phase superbasic medium, which accelerates and improves the polymer solubility in a mixture with DMSO, significantly reducing the viscoelasticity of the resulting solution. The optimum methanol content is up to 60 wt.% related to DMSO. The polymer dissolution rate increases by 5 times in this composition. It found the polymer concentration of 9% is close to the dissolution limit due to the strong solution structuring, which is probably associated with an increase in the amount of water released during the KOH-methanol-DMSO interactions. As a result, the conditions for obtaining high concentrated solutions in a complex, mainly organic solvent for fiber spinning are developed. The viscoelastic properties of solutions are measured in the concentration range of 1–9% at temperatures of 20–50 °C. The flow activation energy for 7 and 9% solutions decreases by 1.5 and 2.3 times, respectively, as the content of methanol in the complex solvent increases from 10 to 60%. [ABSTRACT FROM AUTHOR]

Lipoquinones are the topic of this review and are a class of hydrophobic lipid molecules with key biological functions that are linked to their structure, properties, and location within a biological membrane. Ubiquinones, plastoquinones, and menaquinones vary regarding their quinone headgroup, isoprenoid sidechain, properties, and biological functions, including the shuttling of electrons between membrane-bound protein complexes within the electron transport chain. Lipoquinones are highly hydrophobic molecules that are soluble in organic solvents and insoluble in aqueous solution, causing obstacles in water-based assays that measure their chemical properties, enzyme activities and effects on cell growth. Little is known about the location and ultimately movement of lipoquinones in the membrane, and these properties are topics described in this review. Computational studies are particularly abundant in the recent years in this area, and there is far less experimental evidence to verify the often conflicting interpretations and conclusions that result from computational studies of very different membrane model systems. Some recent experimental studies have described using truncated lipoquinone derivatives, such as ubiquinone-2 (UQ-2) and menaquinone-2 (MK-2), to investigate their conformation, their location in the membrane, and their biological function. Truncated lipoquinone derivatives are soluble in water-based assays, and hence can serve as excellent analogs for study even though they are more mobile in the membrane than the longer chain counterparts. In this review, we will discuss the properties, location in the membrane, and syntheses of three main classes of lipoquinones including truncated derivatives. Our goal is to highlight the importance of bridging the gap between experimental and computational methods and to incorporate properties-focused considerations when proposing future studies relating to the function of lipoquinones in membranes. [ABSTRACT FROM AUTHOR]

Mole fraction solubilities have been measured for anthracene, benzoic acid, 4-tert-butylbenzoic acid, 3-chlorobenzoic acid, 2-hydroxybenzoic acid, 2-methylbenzoic acid, 3-methylbenzoic acid, 3-nitrobenzoic acid and pyrene dissolved in cyclopentanone at 298.15 K using either spectrophotometric or acid-base titrimetric methods. Results of our experimental measurements, combined with published solubility data for several inorganic and organic gases, solubility data for several important crystalline pharmaceutical intermediates and activity coefficient data taken from the published literature, were used to derive Abraham model correlations for solute transfer into anhydrous cyclopentanone solvent from both water and from the gas phase. The derived Abraham model correlations back-calculate the observed experimental data to within 0.10 log units (or less). Reported for the first time are solute descriptor values for several important pharmaceutical intermediates. [ABSTRACT FROM AUTHOR]

Coumarin is a naturally occurring lactone-type benzopyrone with various applications in the pharmaceutical, food, perfume, and cosmetics industries. This hydrophobic compound is poorly soluble in water but dissolves well in protic organic solvents such as alcohols. Despite the extensive use of coumarin, there are only a few reports documenting its solubility in organic solvents, and some reported data are incongruent, which was the direct impulse for this study. To resolve this problem, a theoretical congruency test was formulated using COSMO-RS-DARE for the determination of intermolecular interaction parameters, which allowed for the identification of outliers as suspicious datasets. The perfect match between back-computed values of coumarin solubility and the experimental ones confirms the reliability of the formulated theoretical approach and its adequacy for testing solubility data consistency. As the final approval, the temperature-related coumarin solubility in seven neat alcohols was determined experimentally. Four solvents (methanol, ethanol, 1-propanol, and 2-propanol) were used for reproducibility purposes, and an additional three (1-butanol, 1-pentanol, and 1-octanol) were used to extend the information on the homologous series. The consistency of this extended solubility dataset is discussed in terms of the comparison of remeasured solubility values with the ones already published and within the series of structurally similar solvents. The proposed procedure extends the range of applicability of COSMO-RS-DARE and provides a real and useful tool for consistency tests of already published solubility data, allowing for the approval/disapproval of existing data and filling gaps in datasets. Linear regressions utilizing a 2D molecular descriptor, SpMin2_Bhm, or the distance between solute and solvent in the Hansen solubility space, Ra, were formulated for the estimation of COMSO-RS-DARE integration parameters. [ABSTRACT FROM AUTHOR]

In foaming processes, the blowing agent has a significant influence on the material behaviour and the necessary processing parameters. Low-density polypropylene foam sheets are usually produced with aliphatic hydrocarbons or alkanes as physical blowing agent. Due to the necessary safety precautions and the environmental impact, there is great interest in using alternative blowing agents such as CO2. The sole use of CO2 often leads to corrugation, open cells or surface defects on the foam sheet and therefore requires modifications to the process technology. For this reason, blowing agent mixtures based on CO2 and organic solvents are used for the production of foam sheets. For developing a process model describing the melt flow in the extrusion die and the formation of cells, specific material data like diffusion coefficients are necessary. For CO2 and N2 as sole blowing agent, experimental data exist in the literature. Since no experimental data are available for co-blowing agents such as ethanol at elevated temperatures as they occur in the foam process, these data were calculated using molecular dynamics (MD) simulations. The benefit of MD simulations lies in their ability to reduce the experimental effort and, in particular, to provide data in cases where this data is not available through experimental measurements. The calculated diffusion coefficient values are compared to experimental data from the literature and presented for CO2, N2 and ethanol in polypropylene. The calculated diffusion coefficients of CO2 and N2 are compared with literature results and agree well with them. For the ethanol molecules, the diffusion coefficient is compared relative to the both aforementioned ones considered the larger size of the ethanol molecule compared to N2 and CO2. The results of the diffusion coefficients for ethanol are reasonable compared to the values found for the other two molecules. [ABSTRACT FROM AUTHOR]

Organic solvents of different polarities (polar, semipolar, and nonpolar) are typically used in extraction studies on medical devices for chemical characterization of their constituents (called extractables or leachables, E/L) potentially exposed to patients during clinical uses per ISO 10993-18 (2020). This study evaluates the difference in solubility of semipolar solvents relative to ethanol for a wide range of E/L in hydrophobicity to help the selection of semipolar solvents for extraction studies. The solvents studied include methanol, ethanol, 1-propanol, 2-propanol (IPA), acetonitrile (ACN), acetone, dioxane, dimethylacetamide (DMA), dimethylformamide (DMF), dimethyl sulfoxide (DMSO), and ethylene glycol. A quantitative analysis of solubility difference (relative to ethanol) among these commonly used semipolar organic solvents over a wide hydrophobicity range based on Abraham general solvation model is presented. These semipolar solvents are also classified according to their solvation properties. The results of the calculation include a slope parameter with respect to hydrophobicity ( log 10 P O / W to describe the solubility ratio changes with an increase in E/L hydrophobicity, and an intercept parameter to describe the relative solubility for more polar E/L compounds. The calculation results are also corroborated by other solvent strength parameters. A recommendation on the rational selection of semipolar solvents in extraction studies is finally provided based on the two parameters, extraction type, and instrumental analysis. [ABSTRACT FROM AUTHOR]

• Conceptual density functional theory correctly assesses hydrogen bond acidity/basicity. • Solubility can be described in terms of electrophilicity, nucleophilicity and molecular softness. • HBA can be associated with regional electrophilicity, HBB with regional nucleophilicity, and polarizability with global softness. We present a simple semi-empirical model for solubility in organic solvents, based on the conceptual density functional theory (CDFT) and inspired on the well-known empirical linear solvation energy relationships (LSER) proposed by Kamlet and Taft, where a multiparametric correlation between solubility and empirical descriptors including the hydrogen bond acidity (HBA) and basicity (HBB) plus an additional term describing the dipole polarizability of the solvents was presented. Herein, we set up an analogue model that describes HBA, HBB and dipole polarizability with electronic descriptors derived from the conceptual density functional theory. The main relevant results are as follows: (i) as expected, HBA and HBB properties are not absolute but regional properties, thereby suggesting that any solvent can display both properties with different weights (bifunctional solvents); (ii) while HBA can nicely be represented by a regional electrophilicity index, the HBB property can be accounted for by a regional nucleophilicity. The dipole polarizability is consistently represented by the global softness of the solvent molecule; (iii) the regionalization of these properties is achieved by defining electrophilic and nucleophilic basins within a given solvent molecule by using the electrophilic and nucleophilic Fukui Functions integrated within these basins. The resulting model is validated against the experimental solubility of vanillin and hesperidin in different organic solvents. Further perspectives of the present study should be of special interest in theoretical studies concerning ionic liquids and deep eutectic solvents. [ABSTRACT FROM AUTHOR]

• Solubility of isophthalic acid (IPA) in four different binary solvent systems was determined. • The experimental data was correlated with four thermodynamic models. • Molecular electrostatic potential surface (MEPS) and Hirshfeld surface (HS) analysis were used to investigate the intermolecular interactions. • The dissolution of isophthalic acid (IPA) was a non-spontaneous, endothermic and entropy-driven process. The solubility of isophthalic acid (IPA) in four different binary solvent systems (water + methanol, water + ethanol, water + 1-propanol, and water + isopropanol) was measured by the gravimetric method at atmospheric pressure from 283.15 K to 323.15 K. Under certain solvent compositions, the solubility of IPA increased with increasing temperature. The trend of solubility under isothermal conditions setting differs as the mole fraction of organic solvent increases. The solubility of IPA in water + methanol and water + ethanol systems increased with the mole fraction of methanol or ethanol. In the system of water + 1-propanol and water + isopropanol, as the mole fraction of organic solvent increased, the solubility of IPA increased firstly and then decreased gradually. The Hansen solubility parameters of IPA and selected solvents were analyzed, the analysis showed that the miscibility of IPA with the selected solvent was the result of many factors. Molecular electrostatic potential surface (MEPS) and Hirshfeld surface (HS) analysis were used to investigate the intermolecular interactions. The solubility data were correlated using the Apelblat equation, van't Hoff equation, λh equation, and Jouyban–Acree model. Besides, the vant Hoff equation was employed to analyze the apparent thermodynamic properties of dissolving process including the Gibbs energy, enthalpy and entropy. All positive values indicated that the dissolving process of IPA was non-spontaneous, endothermic, and entropy-driven. [ABSTRACT FROM AUTHOR]

• The solubility of Musk ambrette in single and binary solvents was determined. • The evaluation model for the relationship between solubility and temperature has been established. • The correspondence between solubility and the HSP, π , α , β , and CED of the solvents were discussed. • Molecular simulation was used to analyze the dissolution behavior of Musk ambrette. The solubility of Musk ambrette in i-propanol (IPA), i-butanol (IBA), n-heptane (HPT), n-hexane (HX), cyclohexane (CYH), methyl acetate (MAC), ethyl acetate (EAC), acetone (ACE), IPA + ACE at 278.15 K to 318.15 K was determined. The mole fraction solubility of Musk ambrette in pure IPA at the temperature of 298.15 K were found to be 0.9492 × 10-2 mol·mol−1. The difference is that the solubility of Musk ambrette in ACE reaches 0.2257 mol·mol−1, which is much higher than the solvent mentioned above. The strong intermolecular hydrogen bonding formed by IPA resulted in its lowest solvation capacity for Musk ambrette. In addition, to further investigate the solubility pattern of Musk ambrette, we used 8 models (Van't Hoff, modified Apelblat, Buchowski-Ksiazczak, Yaws, NRTL, Wilson, Jouyban-Acree and Sun model) to fit and obtain a general equation for solubility versus temperature. These results yielded a large amount of statistically significant data. Comparisons revealed that the modified Apelblat and Yaws equation showed the least deviation in forecasting solubility variations with temperature. Meanwhile, we proved that the dissolution of Musk ambrette is a heat-absorbing entropy increasing process by Van't Hoff equation calculation. Δ sol G o for the 12 solvents is in the following order: ACE < MAC < EAC < w = 0.2007 < w = 0.4025 < w = 0.6076 < CYH < w = 0.8070 < HPT < HX < IBA < IPA. Δ sol G o is smaller the easier it dissolves, which is consistent with the law of dissolution. Secondly, we performed thermal analysis and X-ray diffraction tests on Musk ambrette crystals prepared in different solvents, which showed that none of the several systems investigated led to the creation of new crystalline forms or solvatoids, further confirming the suitability of the solvents. Besides, we discuss the correspondence between solubility and the HSP, π , α , β , and CED of the solvents and thus tentatively confirm the significant influence of the solvent properties on solubility. The principle of similarity and compatibility is satisfied for most of the solvents. In particular, the CED values of the larger solvents were not favorable for the solubilization of Musk ambrette. We also analyzed the molecular surface electrostatic potential of Musk ambrette by visualization techniques. Finally, IPA and ACE and their binary solution systems were analyzed by molecular dynamics simulations. The effect of solvent intermolecular interactions on the solubilization pattern was discussed. It was further confirmed that weak interactions of solvent molecules contribute more to the dissolution of Musk ambrette. These findings suggest that the prediction of solvent solubility can be initially achieved by molecular simulation techniques. Undoubtedly, this study will furnish a valuable information for the purification of Musk ambrette. [ABSTRACT FROM AUTHOR]

L-α-glyceryl phosphorylcholine, also referred to as choline ethanol phosphate and phosphocholine glycerophosphate, is a naturally occurring metabolite of water-soluble phospholipids in animals. This molecular property is important for informing the crystallization and purification of drugs. The solubility of L-α-glyceryl phosphorylcholine was determined in ten pure solvents and three mixed solvents under atmospheric pressure. The experimental results indicate that L-α-glyceryl phosphorylcholine is most soluble in methanol and least soluble in acetone. Additionally, the solubility of L-α-glyceryl phosphorylcholine was found to increase with temperature within the experimental range. Furthermore, the solubility of L-α-glyceryl phosphorylcholine in binary solvents is dependent on the proportion of positive solvent and temperature. The solubility of L-α-glyceryl phosphorylcholine increases with the proportion of positive solvent. XRD and DSC results indicate that the crystal form of L-α-glyceryl phosphorylcholine remains unchanged before and after dissolution in the reagent, and its melting point temperature is 413.15 K. Various models, including the modified Apelblat model, λh model, Jouyban-Acree model, SUN model, and CNIBS/R-K model, were used to fit the solubility data of L-α-glyceryl phosphorylcholine in different solvents. The study found that the modified Apelblat model and CNIBS/R-K model were the most appropriate for fitting the data. The KAT-LSER model was used to analyze the molecular interactions between solvents and solutes, revealing that the solvent step method with non-specific polarity/polarization interaction had the greatest impact on solubility. • The solubility of L-α-GPC was determined in ten pure solvents and three binary solvents. • Five models were used to correlate the experimental solubility. • Combine solute structure and solvent effect for analysis. • KAT-LSER model was employed to investigate the solute-solvent interactions. [ABSTRACT FROM AUTHOR]

Hyperbranched polymers (HBPs) have the characteristics of low viscosity, high fluidity, and excellent solubility, which enable them to have many potential applications in various fields. In this study, unequal activity 3,4′,5-trifluoro dibenzophenone (B'B 2) monomers and large volume 9,9-bis (4-hydroxyphenyl) fluorene (A 2) monomers were used to prepare hyperbranched poly (aryl ether ketones) (HBPAEKs) through nucleophilic substitution reaction, and three different hyperbranched HBPAEKs with hydroxy-terminated, fluoro-terminated, and epoxy-terminated groups were synthesized. The properties of the three HBPAEKs were systematically characterized by FT-IR, NMR, GPC, TGA, DSC and others. The solubility test shows that the synthesized HBPAEKs were soluble in most common organic solvents. Thermal analysis results showed that the fluorine-terminated HBPAEKs had excellent thermal stability, with a 5% weight loss temperature of 568 °C (T d5% = 568 °C), which is equivalent to that of poly (ether ether ketone) (PEEK, T d5% = 573 °C). Moreover, by adding HBPAEKs, the Melt Flow Rates (MFR) of PEEK was increased by 59%, which can greatly improve the processability of PEEK. [Display omitted] • Three different terminated HBPAEKs were successfully synthesized with high branching degrees and excellent solubility. • The fluorine-terminated HBPAEKs showing excellent thermal stability, which is comparable to that of PEEK (T d5% =573 ℃). • The HBPAEKs significantly enhanced the MFR of PEEK, which effectively mitigated the poor processability of PEEK. [ABSTRACT FROM AUTHOR]

• The order of cyclosporine solubility was DEGME > ethanol > NMP > 1-butanol > water. • Solubility increased with solvent mass fraction in binary solvent mixed with water. • The solubility was mainly affected by the self-cohesiveness of the solvent. • The solvent effects can be used as a basis of pharmaceutical co-solvent selection. In this study, the solid–liquid equilibrium solubility of cyclosporine in 20 pure solvents and four binary mixtures at 298.15 K were determined using shake-flask technique. Solid-state characterization exhibited that no solvate formation or polymorphic transformation occurred during the dissolution of cyclosporine in any of the solvent systems investigated. The experimental solubilities of cyclosporine in 20 pure mono solvents were ranked as follows: DEGME (2.21 × 10−1) > ethanol (1.22 × 10−1) > NMP (1.15 × 10−1) = 1-butanol (1.15 × 10−1) > dichloromethane (1.07 × 10−1) > acetonitrile (1.02 × 10−1) > PEG 200 (9.78 × 10−2) > PEG 300 (9.12 × 10−2) > chloroform (8.98 × 10−2) > PEG 400 (8.11 × 10−2) > DMF (7.65 × 10−2) > 2-propanol (7.09 × 10−2) > 1-propanol (6.57 × 10−2) > methanol (6.14 × 10−2) > propylene glycol (6.08 × 10−2) > tetrahydrofuran (4.69 × 10−2) > DMSO (2.64 × 10−2) > acetone (1.28 × 10−2) > glycerol (1.35 × 10−5) > water (4.29 × 10−7). In the four binary solvents (DEGME + water, PEG 200 + water, PEG 300 + water, and PEG 400 + water), the mole fraction solubility of cyclosporine increased with increasing mass fractions of the four different organic solvents. Based on the Kamlet-Taft linear solvation energy relationship (KAT-LSER) model, the solubility of cyclosporine was mainly affected by the self-cohesiveness of the solvent, which is related to the interaction between the solvent and the solvent. Additionally, the solubility parameter was used to explain and understand the solubility of cyclosporine in four different binary solvents. To correlate the solubility data of cyclosporine, two models (the Yalkowsky Log-Linear and simplified CNIBS/R–K models) were applied. The calculated data based on two mathematical models and experimental mole fraction solubility data for cyclosporine could provide information for the separation, extraction, purification, crystallization, and selection of suitable a solvent system. [ABSTRACT FROM AUTHOR]

Phthalonitrile (PN) resins are high-temperature-resistant thermosetting polymers which find applications in military as well as aerospace owing to their outstanding performance. At present, most of the PN resins are melt-processed and cured at high temperature via resin transfer moulding owing to their poor solubility in common organic solvents. In the present, embodiment efforts have been made to change the PN resin backbone with adamantane as potential functionality. Mono- and novel bis-adamantylated resorcinols 1a and 1b have been synthesized via Amberlyst-15 solid acid resin-catalysed Friedel–Crafts alkylation reaction, as precursor material for the synthesis of novel phthalonitrile (PN) resin monomers 2a and 2b, respectively. The study includes structural and thermal characterization of resin monomers 2a and 2b along with their solubility in common organic solvents. These resins when cured to their thermosets have demonstrated thermal stability ~ 723 K (5% mass loss) with no glass transition temperature (Tg) up to 673 K. The resin monomers show very good solubility in industry-friendly organic solvents like acetone, ethyl acetate, methyl ethyl ketone and methyl isobutyl ketone. [ABSTRACT FROM AUTHOR]

The solubility of caffeine in aqueous binary mixtures was measured in five aprotic proton acceptor solvents (APAS) including dimethyl sulfoxide, dimethylformamide, 1,4-dioxane, acetonitrile, and acetone. The whole range of concentrations was studied in four temperatures between 25 °C and 40 °C. All systems exhibit a strong cosolvency effect resulting in non-monotonous solubility trends with changes of the mixture composition and showing the highest solubility at unimolar proportions of organic solvent and water. The observed solubility trends were interpreted based on the values of caffeine affinities toward homo- and hetero-molecular pairs formation, determined on an advanced quantum chemistry level including electron correlation and correction for vibrational zero-point energy. It was found that caffeine can act as a donor in pairs formation with all considered aprotic solvents using the hydrogen atom attached to the carbon in the imidazole ring. The computed values of Gibbs free energies of intermolecular pairs formation were further utilized for exploring the possibility of using them as potential solubility prognostics. A semi-quantitative relationship (R2 = 0.78) between caffeine affinities and the measured solubility values was found, which was used for screening for new greener solvents. Based on the values of the environmental index (EI), four morpholine analogs were considered and corresponding caffeine affinities were computed. It was found that the same solute–solvent structural motif stabilizes hetero-molecular pairs suggesting their potential applicability as greener replacers of traditional aprotic proton acceptor solvents. This hypothesis was confirmed by additional caffeine solubility measurements in 4-formylmorpholine. This solvent happened to be even more efficient compared to DMSO and the obtained solubility profile follows the cosolvency pattern observed for other aprotic proton acceptor solvents. [ABSTRACT FROM AUTHOR]

Many active pharmaceutical ingredients (APIs) in the pharmaceutical pipeline require bioavailability enhancing formulations due to very low aqueous solubility. Although spray dried dispersions (SDDs) have demonstrated broad utility in enhancing the bioavailability of such APIs by trapping them in a high-energy amorphous form, many new chemical entities (NCEs) are poorly soluble not just in water, but in preferred organic spray drying solvents, e.g., methanol (MeOH) and acetone. Spraying poorly solvent soluble APIs from dilute solutions leads to low process throughput and small particles that challenge downstream processing. For APIs with basic pKa values, spray solvent solubility can be dramatically increased by using an acid to ionize the API. Specifically, we show that acetic acid can increase API solubility in MeOH:H2O by 10-fold for a weakly basic drug, gefitinib (GEF, pKa 7.2), by ionizing GEF to form the transient acetate salt. The acetic acid is removed during drying, resulting in a SDD of the original GEF free base having performance similar to SDDs sprayed from solvents without acetic acid. The increase in solvent solubility enables large scale manufacturing for these challenging APIs by significantly increasing the throughput and reducing the amount of solvent required. [ABSTRACT FROM AUTHOR]

As people pay more and more attention to environmental protection and the high cost of diesel and gasoline, in order to reduce environmental pollution and use cost, some low-pollution and low-cost components, such as alcohols (ethanol, etc.) and esters (methyl acetate, etc.), are added to diesel and gasoline. Due to the addition of new components, the swelling degree of rubber products will also change. In the literature, this method is often used to test the oil resistance of vulcanizates directly by immersing them in oil. In this paper, a new method is used to predict the oil resistance of vulcanizates. In order to investigate the swelling property of acrylate rubber more comprehensively and predict its oil resistance, the swelling behavior of carboxylic acrylate rubber (AR12) produced by Zeon Corporation (Japan) was measured by swelling method in 24 different organic solvents, and the value of one-dimensional solubility parameter (δ) of AR12 was obtained, ranging from 18 to 22 MPa1/2. The swelling data were analyzed by Hansen Solubility Parameter in Practice software, and the three-dimensional solubility parameter sphere, two-dimensional solubility parameter graph and three-dimensional solubility parameter of AR12 were thus obtained. The values of the three-dimensional solubility parameter of AR12 were δd = 18.30 MPa1/2, δp = 7.10 MPa1/2 and δh = 5.60 MPa1/2, respectively. There is an energy difference (Ra) between AR12 and the 24 solvents, and the swelling ratio (q) of AR12 in the 24 solvents presents an inverse "S"-shaped curve as the Ra values between them change. The experimental results proved that the three-dimensional solubility parameters were more accurate in predicting swelling performance than that of one-dimensional solubility parameter. To verify the experimental results, the relationships of Ra, q and δt values with the volume fractions of two groups of solvent mixtures were established. The experimental results showed the same as those obtained by a single solvent, which further proved the correlation of rubber swelling responses. This new method can be used to predict the oil resistance of rubber, and its advantages compared to traditional methods are using more environmentally friendly and cheaper liquid instead of toxic or expensive liquid. This method can be used not only to evaluate acrylate rubber, but also predict the oil resistance of other polymers. [ABSTRACT FROM AUTHOR]

The present work investigates the solubility of the stable polymorph of celecoxib (CEL) drug in a range of pure organic solvents, including methanol, isopropanol, butanol, ethyl acetate, acetonitrile and toluene, within the temperature range 278–303 K. The solid form used has been characterized by SEM, PXRD, DSC, TGA, FTIR and Raman spectroscopy. The solid form studied exhibited a melting temperature of 437.45 K, with an associated melting enthalpy of 35.93 kJ mol−1. The experimental solubility data obtained was fitted to empirical and semi-empirical models, so that the parameters obtained enable the interpolation of further solubility data within the range explored. In the studied solvents, the solubility decreases in the order: ethyl acetate > acetonitrile > methanol > isopropanol > butanol > toluene. In all the solvents used, except for in toluene, the experimental solubility values are higher than the ideal ones, indicating negative deviation with respect to Raoult's law and favourable solute–solvent interactions. The solubility order of CEL in alcohols correlated well with the solvent polarity and this finding is complemented with the CEL–solvent interactions determined by molecular dynamics simulations. The high solubility of CEL in ethyl acetate is attributed to the similar Hildebrand solubility parameter of both species. [ABSTRACT FROM AUTHOR]

The thermodynamic analysis and preferential solvation of the solubility of sulphanilamide (SA) in five cosolvent mixtures (ethanol + water; 1,4-dioxane + water, acetonitrile + water, dimethyl-sulphoxide + water, and dimethylsulphoxide + water) are presented. The thermodynamic functions are calculated employing the Gibbs and van´t Hoff equations, and the analysis of preferential solvation is developed by inverse Kirkwood–Buff integrals method. The solubility process is endothermic, with entropic favouring in all cases. Finally, according to the solvation parameter, SA is solvated preferentially by water in more polar mixtures, and in DMF + W, and DMSO + W mixtures it is solvated by organic solvent. In the other mixtures (EtOH + W, DIOX + W, and MeCN + W) the SA is solvated by the organic solvent in intermediate mixtures and by water in the less polar mixtures. [ABSTRACT FROM AUTHOR]

In the presented work, a study on the solubility and intermolecular interactions of l -serine and L-cysteine was carried out in binary mixtures of H 2 O + dimethylformamide (DMF), H 2 O + dimethylsulfoxide (DMSO), and H 2 O + acetonitrile (ACN) in the temperature range of T = 288.15 K to 308.15 K. l -serine exhibited the highest solubility in water, while L-cysteine was more soluble in water-DMF. The solvation process was assessed through standard Gibbs energy calculations, indicating the solvation stability order: water-ACN > water-DMSO > water-DMF for l -serine, and water-DMF > water-DMSO > water-ACN for L-cysteine. This study also explored the influence of these amino acids on solvent–solvent interactions, revealing changes in chemical entropies and self-association patterns within the binary solvent mixtures. Variation of solubility of L-cysteine in Water-DMF in various mole fraction concentrations of DMF (X DMF) with temperature (K). [Display omitted] • l-serine shows highest solubility in water, generally decreasing with organic components, except water-ACN solvent system. • L-cysteine is more soluble in water-DMF, solubility order: water-DMF > water-DMSO > water-ACN. • Standard Gibbs energy calculations reveal l -serine's stability: most in water-DMSO, least in water-ACN. • Non-covalent interactions govern stability, l -serine's solvation most affected by DMF, while L-cysteine by ACN. [ABSTRACT FROM AUTHOR]

The electrochemical CO 2 reduction reaction (CO2RR) to organic products is becoming increasingly important. Here, organic electrolytes play a crucial role, since adding salt to organic solvent allows an increase in the current density, and together with supercritical CO 2 organic electrolytes suppress hydrogen evolution during the CO2RR. Since the selectivity to organic products depends on the CO 2 content, CO 2 solubility was investigated in organic electrolytes at different salt concentrations, pressures (up to 150 bar), and temperatures (25 °C and 70 °C). These organic electrolytes included the mixtures NaI-methanol, KSCN-methanol, (C 2 H 5) 4 NBF 4 -acetonitrile, and (C 4 H 9) 4 NBF 4 -acetonitrile. Afterwards, electrolyte Perturbed-Chain Statistical Associating Fluid Theory (ePC-SAFT) was applied to predict the CO 2 solubility in these organic electrolytes. The results showed that i) CO 2 solubility decreased with increasing temperature and salt concentration, ii) dissolving CO 2 may cause a precipitation of salts, and that iii) ePC-SAFT allowed to qualitatively model the CO 2 solubility in organic electrolytes [Display omitted] • CO 2 solubility decreases with increasing temperature and salt concentration in the electrolyte. • CO 2 dissolution in the organic electrolyte may cause salt precipitation. • Organic salts have less influence on CO 2 solubility than inorganic salts. • ePC-SAFT allows qualitatively predicting the CO 2 solubility in organic electrolytes over a broad range of conditions. [ABSTRACT FROM AUTHOR]

• The solubility of four compounds was investigated. • The differences in solubility of two organoaluminium compounds with different configurations were compared. • The experimental solubility data were correlated by different thermodynamic models. • Hirshfeld surface analysis and molecular electrostatic potential were used to explain the solvation behaviour of the compounds. Pyridinyl Schiff base ligands and their supporting organoaluminium compounds have diverse applications in catalysis, medicine, and electrochemistry. In this study, solubility data for two ligands (L1 = 2-(OH)C 6 H 4 CH = N(C 5 H 4 N), L2 = 2-(OH)-5-ClC 6 H 3 CH = N(C 5 H 4 N)) and two organoaluminium compounds (C1 = [2-O-C 6 H 4 CH = NC 5 H 4 N)]AlMe 2 , C2 = [2-O, 4-ClC 6 H 3 CHMeN(C 5 H 4 N)] 2 Al 2 Me 2) with differing configurations were obtained through static analysis. The data showed that at 298.15 K, for L1 , the solubility (102x) order was: toluene (42.339) > ether (23.085) > ethanol (5.025) ≥ methanol (4.888); for L2 , it was: tetrahydrofuran (7.348) > dichloromethane (4.289) > toluene (3.387) > ether (1.210); and for C1 and C2 , the order remained consistent as tetrahydrofuran (C1 :9.192, C2 :13.911) > toluene(C1 :2.904, C2 :6.036) > ether(C1 :2.254, C2 :4.358) > n -hexane(C1 :0.783, C2 :0.975). Subsequently, the solubility data were subjected to fitting using various thermodynamic models. The experimental findings revealed that the majority of the models exhibited good fits, with an average absolute relative deviation (ARD) of < 4 % and an average root mean square deviation (RMSD) of < 0.2 %. Notably, the Wilson model emerged as the most suitable for predicting the solubility of L1 , while the Polynomial model demonstrated superior efficacy in predicting the solubility of L2 , C1 , and C2. In the case of the organic aluminium compound C2 with a distinct configuration, the formation of a dimerized dinuclear metal structure resulted in altered polarity, consequently influencing solubility in various solvents. Molecular electrostatic potential analysis revealed electron densities at the O atom, the NH moiety of the pyridine ring, and proximal regions of the metal atoms, indicative of electronegativity and facilitation of hydrogen bonding. Hirshfeld surface analysis underscored H···H contact as the predominant interaction among the four compounds. Additionally, calculations regarding the apparent thermodynamic functions of L1 and L2 revealed an endothermic dissolution process characterized by increased entropy and driven by enthalpy. These experimental findings provide valuable insights into the properties of pyridinyl Schiff base ligands and their associated organic aluminum compounds, revealing complex relationships among molecular structure, solubility, and thermodynamic properties. They offer valuable clues for further research and application in this field. [ABSTRACT FROM AUTHOR]

This research provides a thorough investigation into the solubility behavior and solution thermodynamics of l-threonine in significant organic solvent systems. The work was done on measuring the actual solubility and subsequently calculating overall transfer solvation free energetics (∆ G energetic 0 i) and transfer entropies (∆ S t 0 i) at a temperature of 298.15 K. These measurements were performed as l-threonine transitioned from water to different water-organic mixed solvents systems. The saturated solubilities of l-threonine were determined using the 'gravimetric method' at five equidistant temperatures namely 288.15 K, 293.15 K, 298.15 K, 303.15 K and 308.15 K. By analyzing the data on solubility, we further obtained the different energies involved in solvation related issues. In the case of single solvents, the nature of solubility of l-threonine was observed like: dimethylsulfoxide (DMSO) < acetonitrile (ACN) < N, N -dimethylformamide (DMF) < ethylene glycol (EG) < water (H 2 O), irrespective of the experimental conditions. Specifically, at 298.15 K, the solubilities of l-threonine in single solvents were found to be as follows: 0.8220 mol per kg of water, 0.3101 mol per kg of EG, 0.1337 mol per kg of DMF, 0.1107 mol per kg DMSO and 0.1188 mol per kg of ACN. This research critically examines the relationship between the experimental saturated solubility of l-threonine and the complex properties influencing its solvation energy in diverse aqueous organic solvent systems. [Display omitted] • Solubility of l-threonine in various cosolvent systems and temperatures: EG-water > DMF-water > ACN-water > DMSO-water. • L-threonine's hydrophilic nature influences its solubility and interactions in water-EG/DMF/DMSO/ACN binary solvent systems. • Solvent molecule dimerization and their relative stabilities impact interactions, as seen in obtained values. • The study provides valuable insights for further scientific research in this area. [ABSTRACT FROM AUTHOR]

In this research, a new Lewis acid-based deep eutectic solvent (LA-DES) was synthesized using diphenhydramine hydrochloride and CoCl2·6H2O, (2[HDPH]:CoCl42−), and identified by FT-IR and 1HNMR techniques. The physicochemical properties of this LA-DES, such as thermal behavior, thermal stability, and solubility in common solvents were also investigated. The catalytic ability of 2[HDPH]:CoCl42− was ascertained in the efficient synthesis of a novel array of thiadiazolo[2,3-b]quinazolin-6-one scaffolds via a one-pot three-component reaction of dimedone/1,3-cyclohexanedione, aldehydes, and 5-aryl-1,3,4-thiadiazol-2-amines/3-(5-amino-1,3,4-thiadiazol-2-yl)-2H-chromen-2-one under solvent-free conditions. This catalyst was also successfully utilized for the synthesis of mono- and bis-thiadiazolo[2,3-b]quinazolin-6-ones from dialdehydes or bis-1,3,4-thiadiazol-2-amine. The simplicity of enforcement, short reaction time, avoidance of toxic organic solvents, scalability of the synthesis procedure, excellent atom economy, high reaction mass efficiency, and low E-factor are other outstanding advantages of this newly developed method. Furthermore, due to the convenient recovery and reuse of LA-DES, this protocol is economically justified and environmentally friendly. [ABSTRACT FROM AUTHOR]