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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]

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]

Porous materials are important for various energy‐related technologies such as catalysis and separation. While porous organic cage compounds are a rather recent addition to the field of porous materials, these discrete nanocavities have since emerged as a versatile functional‐materials platform, facilitated by the solubility of the materials in common organic solvents. In contrast to other frameworks, organic cages are assembled first from modular building blocks in solution and then packed in the solid‐state in a next step. In this minireview, we highlight examples of porous organic cages with focus on how the intrinsic nanopore can be controlled and utilized, especially focusing on their synthesis and the gas sorption properties of smaller intrinsic pores of porous organic cage compounds, porous macrocycles, and other related compounds. [ABSTRACT FROM AUTHOR]

Using non‐halogenated solvents to process organic solar cells is preferable because they are less harmful to human health. However, it is challenging to mitigate the delicate trade‐offs between solubility and pre‐aggregation of organic semiconductors to maintain similar high device efficiencies as those processed by chlorinated solvents. The need for rigorous control of the kinetics between processing temperature and delay time inevitably complicates device processing for achieving reproducible performance. Herein, the authors develop a facile method to achieve proper solubility and pre‐aggregation in non‐halogenated solvents by selecting suitable donor/acceptor materials and subtle tuning of solvent compositions. This results in films with a high degree of ordering and suitably sized phase separation. Solar cells derived from this process can achieve a high power conversion efficiency up to 18%, which is the highest value reported for non‐halogenated solvent processed devices. This impressive result is achieved through synergistically reduced non‐radiative loss and enhanced charge generation. [ABSTRACT FROM AUTHOR]

In this study, a convenient nickel‐catalyzed protocol has been introduced for the Suzuki–Miyaura coupling reaction. A simple mixture of Ni(II) and unfunctionalized β‐cyclodextrin (β‐CD) was used to cross‐coupling of aryl halides with aryl boronic acids for the synthesis of biaryls in water. β‐CD is a water‐soluble seminatural cyclic oligosaccharide, environmentally friendly biomaterial, inexpensive, and commercially available ligand. This ligand with low solubility in usual organic solvents has been used for the synthesis of biaryls in good to excellent yields. The cross‐coupling results in the presence of Ni(II)/β‐CD catalytic system showed that the coupling reaction carried out with appropriate yields for both electron‐rich and electron‐deficient aryl halides. The coupling reaction completed in water as a green solvent. The catalyst was also recycled for four runs with a small decrease in its catalytic activity. The presented new method allows an easier and more cost‐efficient synthesis of biaryls from the reaction of arylboronic acids with various aryl halides in water. [ABSTRACT FROM AUTHOR]

Suitably decorated small aromatic systems can organize stacked structures that display interesting properties arising from their unique morphologies. Although nanographenes produced by top‐down methods have graphitic domains and can in principle be applied for such supramolecular systems, to our knowledge, no such example has been reported thus far. This is partly because of their limited solubility in organic solvents and partly because of their wide lateral size distribution. To realize nanographene‐based supramolecular aggregates, nanographenes carrying alkyl chains with narrow lateral size distributions are employed. We find that the nanographenes undergo self‐assembly and that self‐assembly is regulated by concentration, solvent polarity, temperature, and sonication. Optical measurements and AFM images indicate that stacked structures are possible candidates for aggregates. A molecular mechanics calculation models the interactions in the aggregates. The nanographenes showed concentration‐dependent morphologies on mica, stacked structures at low concentrations and polymer‐like network structures on mica at higher concentrations. [ABSTRACT FROM AUTHOR]

Suitably decorated small aromatic systems can organize stacked structures that display interesting properties arising from their unique morphologies. Although nanographenes produced by top‐down methods have graphitic domains and can in principle be applied for such supramolecular systems, to our knowledge, no such example has been reported thus far. This is partly because of their limited solubility in organic solvents and partly because of their wide lateral size distribution. To realize nanographene‐based supramolecular aggregates, nanographenes carrying alkyl chains with narrow lateral size distributions are employed. We find that the nanographenes undergo self‐assembly and that self‐assembly is regulated by concentration, solvent polarity, temperature, and sonication. Optical measurements and AFM images indicate that stacked structures are possible candidates for aggregates. A molecular mechanics calculation models the interactions in the aggregates. The nanographenes showed concentration‐dependent morphologies on mica, stacked structures at low concentrations and polymer‐like network structures on mica at higher concentrations. [ABSTRACT FROM AUTHOR]

This study uses a cooling sonocrystallization process to recrystallize an active pharmaceutical ingredient, probenecid, and to improve the crystal qualities such as crystal habit and particle size characteristics. To screen the appropriate solvent system, solubility data of probenecid in organic solvent are measured, reported, and correlated by van't Hoff equation. According to the measured solubilities and data acquired from literature, sonocrystallization experiments using solvents with acceptable theoretical recovery are performed. Owing to the satisfactory throughput, yield, and crystal qualities, ethanol is finally decided as the appropriate solvent system. The effect of operating parameters in sonocrystallization including the solution concentration, sonication intensity, sonication duration, and cooling rate using ethanol as the solvent is further studied. With applying power ultrasound, probenecid crystals with narrow size distribution, regular crystal habit, and mean size around 15 µm are successfully produced. Finally, crystal form and spectroscopic property of sonocrystallized sample and probenecid as received from the supplier are compared and confirmed consistent from the analytical results of powder X‐ray diffractometer and Fourier transform infrared spectroscopy. [ABSTRACT FROM AUTHOR]

Herein, a [3+2] cycloaddition of aza‐oxyallylic cations with ethynylbenziodoxolones for synthesis of new λ3‐iodanes containing spirocyclic 4‐oxazolidinone has been developed. This cyclic λ3‐iodanes display stability in air and excellent solubility in organic solvent. Using them as substrate, both the 4,1‐benzoxazepine‐2,5‐diones and symmetrical 1,3‐diynes derivatives were afforded in high yield under copper(I)‐catalyzed conditions. [ABSTRACT FROM AUTHOR]

It is shown in this work that high electron affinity can be combined with high solubility and practical accessibility in corannulene‐based electron acceptors. The electron affinity originates from the presence of three different types of electron‐withdrawing groups (imide, sulfone, and trifluoromethyl) on the aromatic scaffold. The imide substituent further hosts a long alkyl chain (C18H37) to boast solubility in a wide range of organic solvents. The synthesis is modular and consists of three simple steps from a commonly available corannulene derivative with an overall isolated yield of 22–27 %. [ABSTRACT FROM AUTHOR]

Systematic variation of the 1,4‐dioxane (dx) concentration during the precipitation of sparingly soluble [MgBr2(dx)2] from ethereal Grignard solutions of RMgBr has allowed the structural investigation of crystallized [R2Mg(dx)n] (n=1, 1.5, 2, and 3), which form during this dioxane method, depending on the bulkiness of R. The numbering of the complexes explored in this study is based on the number n of dioxane molecules per magnesium atom, followed by the substituent R; an apostrophe denotes coordination polymers. The following derivatives were studied by X‐ray crystal‐structure determination and NMR spectroscopy: n=1: [Me2Mg(μ‐dx)]∞ (1′‐Me) and [nPr2Mg(μ‐dx)]∞ (1′‐nPr); n=1.5: [{iPr2Mg(dx)}2(μ‐dx)] (1.5‐iPr), [{oTol2Mg(dx)}2(μ‐dx)] (1.5‐oTol), and [(Me3Si‐C≡C)2Mg(dx)1.5]∞ (1.5′‐C2SiMe3); n=2: [tBu2Mg(dx)2] (2‐tBu) and [oTol2Mg(dx)2] (2‐oTol); n=3: [Ph2Mg(dx)3] (3‐Ph). In the structure types 1′, 1.5, and 2, the magnesium atom exhibits the coordination number 4, whereas pentacoordinate metal atoms are observed in types 3 and 1.5′. The structure type 2′ is realized for [(Ph‐C≡C)2Mg(dx)2]∞ (2′‐C2Ph), [MgCl2(dx)2]∞ (2′‐Cl), and [MgBr2(dx)2]∞ (2′‐Br) with hexacoordinate metal atoms. The solubility of the dioxane adducts in common organic solvents strongly depends on the degree of aggregation with the solubility decreasing from molecular to strand to layer structures. [ABSTRACT FROM AUTHOR]

New aromatic (co)polyesters containing pendant propargyloxy groups were synthesized by phase transfer‐catalyzed interfacial polycondensation of 5‐(propargyloxy)isophthaloyl chloride (P‐IPC) and various compositions of P‐IPC and isophthaloyl chloride with bisphenol A. FTIR and NMR spectroscopic data, respectively, revealed successful incorporation of pendant propargyloxy groups into (co)polyesters and formation of (co)polyesters with desired compositions. (Co)polyesters exhibited good solubility in common organic solvents such as chloroform, dichloromethane, and tetrahydrofuran and could be cast into transparent, flexible, and tough films from chloroform solution. Inherent viscosities and number average molecular weights of (co)polyesters were in the range 0.77–1.33 dL/g and 43,600–118,000 g/mol, respectively, indicating the achievement of reasonably high‐molecular weights. The 10% weight loss temperatures of (co)polyesters were in the range 390–420 °C, demonstrating their good thermal stability. (Co)polyesters exhibited Tg in the range 146–170 °C and Tg values decreased with increase in mol % incorporation of P‐IPC. The study of non‐isothermal curing by DSC indicated thermal crosslinking of (co)polyesters via propargyloxy groups. The utility of pendant propargyloxy group was demonstrated by post‐modification of the selected copolyester with 1‐(4‐azidobutyl)pyrene, 9‐(azidomethyl)anthracene, and azido‐terminated poly(ethyleneglycol) monomethyl ether via copper(I)‐catalyzed Huisgen 1,3‐dipolar cycloaddition reaction. FTIR and 1H NMR spectra confirmed that click reaction was quantitative. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 588–597 This article describes the introduction of pendant propargyloxy functionality into aromatic (co)polyesters by functional monomer approach involving the use of 5‐(propargyloxy)isophthaloyl chloride as a difunctional monomer. The curing characteristics of a thermally induced crosslinking reaction are studied by non‐isothermal DSC. The quantitative post‐modification of the propargyloxy groups is carried out via copper(I)‐catalyzed azide‐alkyne click reaction with representative azides to obtain modified polyesters with interesting properties. [ABSTRACT FROM AUTHOR]

Organic synthesis without an organic solvent is still the exception. In this microreview, we discuss and compare different synthetic methods that proceed in the absence of conventional organic solvents. This includes solvent‐free methods in solids (mechanochemistry and solid‐state photochemistry), and in neat liquids (thermal and photocatalytic), as well as the application of unconventional solvents, such as ionic liquids and deep‐eutectic solvents. The different approaches are briefly introduced and examples illustrate their specific advantages, followed by a critical discussion of their limitations. Some methods have the intrinsic benefits of solvent‐free operation, such as avoiding solubility problems and side‐reactions with the solvent. However, every method has specific advantages and the demand of the synthetic application is crucial for selecting the best technique. [ABSTRACT FROM AUTHOR]

Abstract: Major disadvantages of black phosphorus (BP) are its poor air‐stability and poor solubility in common organic solvents. The best way to solve this problem is to incorporate BP into a polymer backbone or a polymer matrix to form novel functional materials that can provide both challenges and opportunities for new innovation in optoelectronic and photonic applications. As a proof‐of concept application, we synthesized in situ the first highly soluble conjugated polymer‐covalently functionalized BP derivative (PDDF‐g‐BP) which was used to fabricate a resistive random access memory (RRAM) device with a configuration of Au/PDDF‐g‐BP/ITO. In contrast to PDDF without memory effect, PDDF‐g‐BP‐based device exhibits a nonvolatile rewritable memory performance, with a turn‐on and turn‐off voltages of +1.95 V and −2.34 V, and an ON/OFF current ratio of 104. The current through the device in both the ON and OFF states is still kept unchanged even at 200th switching cycle. The PDDF/BP blends show a very unstable memory performance with a very small ON/OFF current ratio. [ABSTRACT FROM AUTHOR]

Abstract: Chemical conjugation between hydrophilic and hydrophobic components is difficult because of their extremely different solubility. Herein, we report a new versatile method with a solid‐phase‐assisted disulfide ligation to overcome the difficulty of conjugation attributed to solubility. The method involves two steps in a one‐pot process: 1) loading of a hydrophobic molecule onto a resin in an organic solvent, and 2) release of the solid‐supported hydrophobic molecule as a conjugate with a hydrophilic molecule into an aqueous solvent. This strategy allows the use of a suitable solvent system for the substrates in each step. Conjugates of a water‐insoluble drug, plinabulin, with hydrophilic carriers that could not be prepared by solution‐phase reactions were obtained in moderate yields (29–45 %). This strategy is widely applicable to the conjugation of compounds with solubility problems. [ABSTRACT FROM AUTHOR]

In this study water solubility curves were constructed and calorimetric measurements obtained for reverse micellar systems consisting of an alcohol (isopropanol or butanol), surfactant (AOT) and organic solvent (isooctane or hexane). Also evaluated were the effects of alcohol and solvent type and surfactant concentration on the extraction of the α-lactalbumin (α-la). From the obtained solubility diagrams for ternary systems, it was concluded that isooctane presented the highest water solubility capacity in the center of the micelle systems with hexane, since isooctane has greater molecular volume and greater effect of the surfactant aggregation number. With respect to the alcohols, it was observed that isopropanol and butanol act in the system as a co-surfactant, since they prefer to adsorb at the water/solvent interface. It was also verified that butanol improved water solubility inside the reverse micellar due to its contribution to increase the critical packing parameter. The amount of α-la extracted increased proportionally with the AOT concentration for systems with isooctane and hexane. However, for systems with the latter solvent, the concentration of extracted protein first increases and then decreases. The extraction power of reverse micellar systems with isooctane was influenced by the type of alcohol with butanol showing better results. For systems containing hexane there was no effect of the alcohol added to the system on extraction power of α-lactalbumin. [ABSTRACT FROM AUTHOR]

Supramolecular chemistry utilizing the macrocyclic hosts cyclodextrins (CDs) and cucurbit[ n]urils (CB[ n]s) is traditionally performed in aqueous media; however, their solubility is typically poor, especially for the family of CB[ n]s. Through derivatization of these macrocycles their solubility can be augmented to enable enhanced solubility in water and in some organic solvents. The increase in solubility of these derivatized macrocycles allows for their use in a wider range of chemical environments and giving rise to myriad potential applications. The dissolution of parent CDs (α-, β- and γ-) and CB[ n]s ( n=6-8) in deep eutectic solvents (DES) is reported, showing dramatic enhanced solubility of the larger species in both families, CB[7] and CB[8] as well as β- and γ-CD, respectively. Furthermore, the host-guest properties are maintained in this new solvation medium. [ABSTRACT FROM AUTHOR]

D5h-symmetric fullerene C70 (D5h-C70) is one of the most abundant members of the fullerene family. One longstanding mystery in the field of fullerene chemistry is whether D5h-C70 is capable of accommodating a rare-earth metal atom to form an endohedral metallofullerene M@D5h-C70, which would be expected to show novel electronic properties. The molecular structure of La@C70 remains unresolved since its discovery three decades ago because of its extremely high instability under ambient conditions and insolubility in organic solvents. Herein, we report the single-crystal X-ray structure of La@C70(CF3)3, which was obtained through in situ exohedral functionalization by means of trifluoromethylation. The X-ray crystallographic study reveals that La@C70(CF3)3 is the first example of an endohedral rare-earth fullerene based on D5h-C70. The dramatically enhanced stability of La@C70(CF3)3 compared to La@C70 can be ascribed to trifluoromethylationinduced bandgap enlargement. [ABSTRACT FROM AUTHOR]

Using linear side chains for conjugated polymers is hindered by their limited solubility in common organic solvents, creating problems during purification and processing, whereas branched alkyl chains generally preclude interchain interdigitation because their bulkiness usually hinders interchain interactions. To compensate the adverse effects from each side chain, it is shown that replacing commonly employed 2-ethylhexyl (2EH) solubilizing groups with branched 5-ethylnonyl (5EN) chains not only improves solution processability to PCDT-BT polymer, but also induces an advantageous change in polymer self-assembly and backbone orientation in thin films that correlates with an increase in transistor performance. [ABSTRACT FROM AUTHOR]

The Front Cover shows a piece of ice in one glass and water in another glass; the former represents the solid phase of an unsubstituted directly‐2,2'‐linked tetracene dimer (2,2'‐TD), and the latter is the solution of the multi‐substituted 2,2'‐TD. The unsubstituted 2,2'‐TD reported by Rehan's group in 2017 could not be characterized, which may have been be due to its low solubility. On the other hand, the multi‐substituted 2,2'‐TD was highly soluble in organic solvents and could be characterized by several techniques such as NMR, UV/Vis spectroscopy, and X‐ray crystallography. More information can be found in the Full Paper by T. Honda, C. Kitamura et al. [ABSTRACT FROM AUTHOR]

The impact of the Z‐isomer content of carotenoids, β‐carotene and astaxanthin, on their solubility in organic solvents and crystallinity is investigated. Carotenoid samples containing different Z‐isomer contents are prepared from the high‐purity all‐E‐isomers by the thermal isomerization and filtering technique: β‐carotene, 27.4% and 89.8% Z‐isomer content; astaxanthin, 34.5% and 63.2% Z‐isomer content. As the Z‐isomer content of the carotenoids increases, their relative solubility markedly improves, e.g., the solubility in ethanol of β‐carotene containing 89.8% Z‐isomer is ≈250 times higher than that of the all‐E‐isomer. Moreover, differential scanning calorimetry (DSC), powder X‐ray diffraction (XRD), and scanning electron microscopy (SEM) analyses clearly indicate that the (all‐E)‐carotenoids are present in the crystal state, while the Z‐isomers are present in an amorphous state. A number of studies have reported that the Z‐isomerization of carotenoids induced changes in bioavailability and antioxidant activity. This may be due to the change in physicochemical properties such as solubility and crystallinity by Z‐isomerization. In addition, these changes are important information for improving carotenoid processing. Practical Applications: Carotenoids in plants occur predominantly in the all‐E‐configuration, whereas the Z‐isomers are present in the human body in considerable quantity. Since (all‐E)‐carotenoids have low solubility in solvents and high crystallinity, efficiencies of those processing such as solvent extraction, micronization, and emulsification are low. However, this study experimentally reveals that solubilities of carotenoids, β‐carotene and astaxanthin, are significantly improved and crystallinities of them are reduced by Z‐isomerization. These fundamental data should contribute to improvement of carotenoids processing efficiency. The effect of the Z‐isomer content of carotenoids, β‐carotene and astaxanthin, on their solubility in organic solvents and crystallinity is investigated. Increasing the Z‐isomer contents of the carotenoids, those solubility improved and those crystallinity reduced. The effect of the Z‐isomer content of carotenoids, β‐carotene and astaxanthin, on their solubility in organic solvents and crystallinity is investigated. Increasing the Z‐isomer contents of the carotenoids, those solubility improved and those crystallinity reduced. [ABSTRACT FROM AUTHOR]

Review: 211 refs. [ABSTRACT FROM AUTHOR]