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The new experimental vapor–liquid equilibrium data for CO2 solubility into two different combinations of alkanolamine + amino acid, alkanolamine + chemical additive, and one aqueous alkanolamine we...

Extractive crystallization is a promising method for preparing salts from their aqueous solutions. It is topical to carry out extractive crystallization so that reuse the solvent. One aim of our study was to find optimal conditions for the extractive crystallization of sodium chloride via studying phase equilibria and critical phenomena in the sodium chloride–water–diisopropylamine ternary system in the range 10.0–90.0°C. One more aim was to decide whether sodium chloride is useful for salting-out diisopropylamine from its aqueous solutions. The water–diisopropylamine system has a lower critical solution temperature (27.3°C). The phase-transition temperatures were evaluated by the visual polythermal method, and polythermal phase diagrams of mixtures of ternary system’s components were plotted. Temperature dependences of the critical solution composition and the distribution coefficient (Kd) of diisopropylamine between the aqueous and organic monotectic phases were elucidated. The maximum value of Kd (480) was reached at 90.0°С. The yield of NaCl crystals was found to increase with increasing amine concentration in the ternary mixtures. The highest sodium chloride yield (49%) from a water–salt solution containing 26 wt % salt was observed at 27.3°С after 90.0 wt % diisopropylamine was added.

A rapid GC-FID method was developed to simultaneously determine residual levels of triethylamine (TEA), 1,1,3,3-tetramethylguanidine (TMG), and diisopropylamine (DIPA) in the synthetic route of an active pharmaceutical ingredient (API). Due to the severe absorption of amines on GC stationary phases, GC columns with various stationary phases were evaluated for optimal peak shape and reproducibility. The final conditions used the Agilent CP-Volamine column to resolve the three amines in 12 min. Various inlet liners were also screened to further improve the sensitivity of the analysis. The Restek Siltek® liner was selected to achieve the desired detectability for the method. The quantitation limits were 4, 3, and 4 μg/mL for TEA, DIPA, and TMG in the presence of API, respectively. All three amines showed good linearity (r > 0.999) and recoveries (> 90%) over the concentration range of 3 to 16 μg/mL. The testing of residual amines was initially performed at the penultimate stage of the synthesis. However, this work demonstrates that TMG can act as a proton sponge to react with salicylic acid, the counter ion of the penultimate, to form a volatile component that elutes at a different retention time. Consequently, in the final method, these three amines were monitored in the final API to circumvent the matrix interference. Key parameters of the method were qualified per method validation requirements in ICH guidelines. The method was successfully applied for batch testing during development and implemented as an in-process control procedure at manufacturing sites., Graphical abstract Image 1, Highlights • A fast and sensitive GC-FID method was developed to monitor the residue of three volatile amines in an API. • The detection of 1,1,3,3-Tetramethylguanidine (TMG) at trace level is reported the first time. • The method circumvented the interference of sample matrix since TMG can react with carboxylic acid in penultimate. • The method was qualified per ICH guideline and implemented as an in-process-control procedure.

Sodium hydride, potassium carbonate, and other bases are commonly used for N-alkylation of heterocyclic compounds. This report reveals the problems associated with N-benzylation of isatoic anhydride and identifies the plausible byproduct structures formed during the reaction. Subsequently, a novel breakthrough methodology has been developed using diisopropylamine and tetra butyl ammonium bromide. It gives excellent yields >88% in a short reaction time (2 h) at 30 °C with no byproducts, saving on processes as the pure product is directly obtained.

APO-11 aluminophosphate molecular sieve was prepared by hydrothermal method of aluminum hydroxide with diisopropylamine. Ni–P/APO-11 amorphous alloy catalysts were prepared by chemical reduction method and used for the hydrogenation of α-pinene reaction. The catalysts were characterized by X-Ray photoelectron spectroscopy (XPS), Nitrogen adsorption–desorption isotherms (BET), scanning electron microscope (SEM), transmission electron microscope (TEM) and fourier transform infrared spectrometer (FT-IR).The prepared conditions of the Ni–P/APO-11 catalysts played important roles on the hydrogenation of α-pinene reaction. It was found that the preparation temperature, P/Ni molar ratio and pH value had great influence on the reduction dosage, dispersion and particle sizes of the catalysts, thus affecting the reactivity of the catalysts. The appropriate reaction conditions explored were at 30 °C, n(P/Ni) = 5 and pH = 8, obtaining a 90.65% conversion of α-pinene and 97.87% selectivity to cis-pinane. Under these conditions, the catalysts exhibited better repeatability and stability.

We have evaluated the vapor-liquid equilibrium and heat of absorption of CO2 over water-lean mixtures of the amines diisopropylamine and N,N-diethylethanolamine (DEEA). This extends our previous re...

The Lewis acidities of a series of [n]magnesocenophanes (1 a–d) have been investigated computationally and found to be a function of the tilt of the cyclopentadienyl moieties. Their catalytic abilities in amine borane dehydrogenation/dehydrocoupling reactions have been probed, and C[1]magnesocenophane (1 a) has been shown to effectively catalyze the dehydrogenation/dehydrocoupling of dimethylamine borane (2 a) and diisopropylamine borane (2 b) under ambient conditions. Furthermore, the mechanism of the reaction with 2 a has been investigated experimentally and computationally, and the results imply a ligand‐assisted mechanism involving stepwise proton and hydride transfer, with dimethylaminoborane as the key intermediate., Magnesocenophanes in catalysis: The dehydrocoupling of dimethylamine borane to cyclic tetramethyldiborazane under ambient conditions, catalyzed by a [1]magnesocenophane, is described. This is the first example of a magnesium‐based catalyst for this reaction that operates at room temperature. Based on experimental investigations and DFT calculations, a ligand‐assisted mechanism involving stepwise proton and hydride transfer is proposed.

A series of new iridium(III) cyclometalated complexes (4tfmpiq)2Ir(tiptha), (4tfmpiq)2Ir(phdiptha), (4tfmpiq)2Ir(fphdiptha) and (4tfmpiq)2Ir(ipdptha) (4tfmpiq = 4-(4-(trifluoromethyl)phenyl)isoquinoline, tiptha = 1,1,3-triisopropylthiourea, phdiptha = 1,1-diisopropyl-3-phenylthiourea, fphdiptha = 3-(4-fluorophenyl)-1,1-diisopropylthiourea, ipdptha = 3-isopropyl-1,1-diphenylthiourea) containing a unique four-membered ring Ir–S–C–N backbone were facilely synthesized under mild conditions. By introducing different substituents such as isopropyl, phenyl, 4-fluorophenyl, diisopropylamine and diphenylamine on the thiourea ancillary ligands, not only the S–C–N ligands can be extensively derived, but also the emission colors (λpeak = 627–636 nm) and photoluminescence quantum efficiencies (ΦP = 38.0–42.0%) can be regulated. Employing these complexes as emitters, the organic light emitting diodes (OLEDs) exhibited good performances with a maximum external quantum efficiency (EQEmax) of 13.1% for saturated red emission with CIE coordinates of (0.68, 0.32). These results demonstrate the great potential of the S–C–N ancillary ligands for developing new Ir(III) complexes towards OLED applications.

Highly luminous lanthanide metal–organic gels (Ln-MOGs) can act as fluorescent probes for the detection of organic amines and can also be used to build white-light emitting materials based on the different luminescent properties of lanthanide ions. Here, we reported a Ln-MOG constructed with a 3,5-di(2′,4′-dicarboxylphenyl)benozoic acid (DPBA) ligand and Tb3+. Tb-MOG has an excellent fluorescence detection effect on organic amines including ethylenediamine, triethylamine, diisopropylamine and aniline in aqueous solution, and their detection limits reach a sub-ppm level. Considering the practicality, a Tb-MOG testing paper was prepared by a spin coating process, which can detect volatile organic amine vapors with good recyclability. Additionally, a single-phase white-light Tb0.84Eu0.16-MOG material was realized by in situ doping of Tb-MOG with Eu3+ and reasonably utilizing the blue emission of DPBA.

Polyurethanes (PU) constitute one of the most versatile class of polymers with respect to composition, properties and applications. However, there are a lack of synthetic strategies capable of producing PU with controlled architecture, chain end functionality, molar mass and low molar mass dispersity (Ð); these characteristics could considerably improve the use of PU in advanced applications. In this study, we report a method for synthesizing polyurethanes based on the dissociation equilibrium of hindered urea groups. Diisopropylamine reacts promptly with isocyanates, forming hindered ureas in a dynamic fashion and establishing a dissociation equilibrium shifted towards hindered urea formation. The equilibrium reduces the concentration of isocyanates susceptible to the polyaddition with diols and, therefore, the step growth polymerization follows a controlled pathway resulting in PU with Ð

The addition of lithium enolates and TMS ethers of cyclohexanone and cyclododecanone to levoglucosenone in the presence of Lewis acids was studied. It was established that the optimal way to obtain of Michael adducts involves the reaction levoglucosenone at −78°C with lithium enolates of cyclohexanone and cyclododecanone in the presence of ZnCl2. Additional amounts of Michael adducts can be obtained by treatment of 1,2-adducts with lithium diisopropylamine. 1,2-Adducts are best prepared by the reaction of the corresponding lithium enolates with levoglucosenone in the presence of Ti(Oi-Pr)4.

Hypersaline brines are of growing environmental importance but are technologically under-served by today’s desalination methods. Temperature swing solvent extraction (TSSE) is a radically different desalination technology that is membrane-less and not based on evaporative phase change. TSSE utilizes low-temperature heat and a low-polarity solvent with temperature-dependent water solubility for the selective extraction of water over salt from saline feeds. This study demonstrates TSSE desalination of high-salinity brines simulated by NaCl solutions with three amine solvents: diisopropylamine (DIPA), N-ethylcyclohexylamine (ECHA), and N,N-dimethylcyclohexylamine (DMCHA). We show that TSSE can desalinate brines with salinities as high as ≈234000 ppm total dissolved solids (i.e., 4.0 M NaCl) and achieve salt removals up to 98.4%. Among the solvents, DIPA exhibited the highest water extraction efficiency whereas ECHA and DMCHA produced water with the lowest salt content and solvent residue content, respectively. Lastly, a high water recovery of >50% was demonstrated for TSSE desalination of 1.5 M NaCl brine using DIPA in semibatch experiments with multiple extraction cycles. This study underscores the unique capabilities of TSSE for the desalination of hypersaline brines.

The amidation reaction between 4-chlorobenzoyl chloride (CBC) and diisopropylamine (DIPA) has been successfully intensified with the implementation of a number of process intensification (PI) optio...

Lithium amides have been proved to be effective anionic initiators for the anionic polymerization of acrylonitrile to get high molecular weight polyacrylonitrile in this study. Polyacrylonitrile with weight-average molecular weight ranging from 1.02 × 106 g/mol to 1.23 × 106 g/mol (Mw/Mn = 1.9–2.2) could be prepared utilizing lithium amides derived from diisopropylamine, diethylamine, hexamethyldisilazane, dicyclohexylamine, and 2,2,6,6-tetramethylpiperidine as initiators. The polymerization of acrylonitrile proceeded in a homogeneous manner in N,N-dimethylformamide and insignificant contribution of side reactions was confirmed.

Five red cyclometalated iridium(III) complexes containing the unique four-membered ring Ir–S–C–S backbone with different dithiocarbamate derivatives as ancillary ligands and 1-(4-(trifluoromethyl)phenyl)isoquinoline (4tfmpiq) as the main ligand were synthesized at room temperature within ten minutes. The emission color (λpeak = 607–619 nm) and photoluminescence quantum efficiency (PLQY) (ΦP = 36.6–63.0%) can be effectively tuned by introducing different electron – donating substituents such as diisopropylamine (dipdtc), diphenylamine (dpdtc), bis(4-(tert-butyl)phenyl)amine (tBudpdtc), carbazole (Czdtc) and 3,6-di-tert-butyl-9H-carbazole (tBuCzdtc) into the dithiocarbamate ancillary ligands. Employing (4tfmpiq)2Ir(dipdtc) as the emitter, the organic light emitting diodes (OLEDs) with double emitting layers exhibit good performances with a maximum current efficiency (ηc,max) of 18.67 cd A−1, an EQEmax of 20.69% and low efficiency roll-off with an EQE of 18.11% at the practical luminance of 1000 cd m−2. The Commision Internationale de L’Eclairage coordinates of (0.660, 0.337) are quite close to the National Television System Comittee (NTSC) standard red emission. These results demonstrate that by introducing different electron – donating substituents into the dithiocarbamate ligands, the diversity of the S–C–S ligands is greatly enriched for red Ir(III) complexes and the corresponding OLEDs.

The synthesis of a polymer containing alternating titanafluorene and arylene ethynylene moieties is described. The polymerization of a 2,7-dibromo-9-titanafluorene derivative with 1,4-dioctyloxy-2,5-diethynylbenzene is carried out at 70 °C for 48 h in tetrahydrofuran (THF) in the presence of palladium dichloride/4,5-bis(diphenylphosphino)-9,9-dimethylxanthene as a catalyst and diisopropylamine as a base to produce a dark red polymer. The polymer thus obtained is soluble in organic solvents and stable towards both air and moisture. In the UV-vis absorption spectrum of the polymer, the absorption maxima (λmax) are observed at 321 nm and 395 nm, which are bathochromically shifted compared to those of a model compound of the repeating unit, a 2,7-bis(phenylethynyl)titanafluorene derivative (λmax = 309 nm and 364 nm). The optical band gap (Eg) of the polymer is estimated to be 2.8 eV on the basis of the absorption onset, which is narrower than that of the model compound (3.1 eV).

This study presents novel sulfolane based non-aqueous CO2 capture solvents, as an alternative solution for capturing CO2 from industrial processes. In order to select the most promising amine system, five different amines were tested by monitoring CO2 absorption and desorption processes using the time-base Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy. During absorption experiments, we observed the formation of Monomethyl Carbonate (MMC) in diisopropylamine (DIPA) and 2-amino-2-methyl-1-propanol (AMP) systems, while carbamate was observed as the main product for the other three amine systems tested. In regeneration experiments, the MMC could be desorbed relatively easily from the amine solution at a mild temperature.

Skeletal reorganization is a type of intriguing processes because of their interesting mechanism, high atom-economy and synthetic versatility. Herein, we describe an unusual, divergent skeletal reorganization of N-sulfonyl ynamides. Upon treatment with lithium diisopropylamine (LDA), N-sulfonyl ynamides undergo a skeletal reorganization to deliver thiete sulfones, while the additional use of 1,3-dimethyl-tetrahydropyrimidin-2(1H)-one (DMPU) shifts the process to furnish propargyl sulfonamides. This skeletal reorganization divergence features broad substrate scope and scalability. Mechanistically, experimental and computational studies reveal that these processes may initiate from a lithiation/4-exo-dig cyclization cascade, and the following ligand-dependent 1,3-sulfonyl migration or β-elimination would control the chemodivergence. This protocol additionally provides a facile access to a variety of privileged molecules from easily accessible ynamides., Skeletal reorganizations are intriguing processes in chemical synthesis due to their mechanism, atom-economy and synthetic versatility. Herein, the authors describe a divergent skeletal reorganization of N-sulfonyl ynamides to thiete sulfones and propargyl sulfonamides.

The bulk supply of the antiviral C-nucleoside analogue remdesivir is largely hampered by a low-yielding C-glycosylation step in which the base is coupled to the pentose unit. Here, we disclose a significantly improved methodology for this critical transformation. By utilizing diisopropylamine as a cost-effective additive, the addition reaction furnishes an optimal yield of 75% of the desired ribofuranoside adduct, representing the highest yield obtained thus far for this key step. The method proved suitable for hectogram scale synthesis without column chromatographic operations.

Solvent extraction desalination has shown to be a promising energy-efficient technique when compared to separation processes usually employed. Despite the remarkable impact of the organic solvent’s molecular characteristics on this process, few studies have been carried out so far to explicitly ascertain the influence of these characteristics on the solubility of water in the solvent. Here, we assess the viability of four different imidazole-based solvents and compare them to an amine compound for solvent extraction desalination of high salinity brines. All-atom molecular simulations of pure solvent and water-solvent bulk mixtures are used to ascertain the influence of the solvents’ molecular structures on solvent–solvent and solvent–water interaction. Our results show that water solubilization in imidazole-based solvents is an endothermic process, while for a secondary amine (diisopropylamine) it is an exothermic process. We show that imidazole-based solvents can be designed to provide characteristics favorable to brine desalination.

A simple quinoline-based derivative (AQDPA) was developed as a highly efficient fluorescent sensor for sensing Zn2+ and sequential recognition of pyrophosphate and sulfur ions. This chemosensor was synthesized from diisopropylamine and 2-chloro-N-(quinolin-8-yl)acetamide. The non-fluorescence sensor displayed significant and specific fluorescence enhancement after binding to Zn2+ with high selectivity. The fluorescence titration analysis shows a detection limit for Zn2+ at 4.1 × 10−8 M. The sensing mechanisms of AQDPA binding to Zn2+ were supported by 1H NMR, HR-MS analysis, and density functional theory (DFT) study. Moreover, the fluorescence imaging in HeLa cells suggested that this simple sensor had great potential in the application of biological imaging.

The ac dielectric and electrical behaviors of the pure poly(N-isopropylacrylamide) (PNIPAM) and PNIPAM/8% by wt graphite-filled composite at room temperature and that of partially degraded polymer were investigated. TGA measurements showed that thermal degradation of the pure PNIPAM and PNIPAM/8% by wt graphite-filled composite polymers were a single-stage process under nitrogen atmosphere. Phenomenon of depolymerization from thermal degradation of PNIPAM and PNIPAM/8% by wt graphite-filled composite was revealed as a significant difference in comparison to polyacrylamide and other analogous. In degradation studies, while the N-isopropylacrylamide was detected as 25% by mole among products of degradation of PNIPAM/8% graphite-filled composite, this event was 9% by mole for that of pure PNIPMA. The major evolved products were found to be molecules such as N-isopropylacrylamide, cyclic-imides, diisopropylamine, dimer and trimer. Degradation mechanism of the polymer was briefly suggested and evaluated the relationship between structures of the pure PNIPAM and PNIPAM/8% graphite-filled composite polymers.

Naphtho[1,2-b] furans were synthesized via a Pd-catalyzed reaction of diazonaphthoquinones and terminal alkynes in the presence of CuI and diisopropylamine. This method was then successfully applied to the synthesis of natural product, furomollugin.

In this work, we have synthesized four SAPO-34/44 (framework type code: CHA) samples by utilizing different organic structure-directing agent (OSDA) such as cyclohexylamine (CA), n-butylamine (BA), diisopropylamine (DIPA), and dipropylamine (DPA). An approach combining Rietveld refinement and simulated annealing has been successfully applied to determine the location of the individual OSDA and the host (inorganic framework)-guest (OSDA) interaction. The final Rietveld refinements show that 1) one cha cage can be occupied by either two OSDAs (CA and BA) in the up-and-down arrangement or one OSDA (DIPA and DPA) in the longitudinal configuration and 2) the classical hydrogen bond between CA/BA and the inorganic framework in SAPO-44-CA and SAPO-34-BA could be identified. The host-guest interactions among these four samples are also investigated by FT-IR, which are consistent with Rietveld refinement results. The approach employed here could be applicable for the host-guest investigation in other crystalline porous materials.

Diisopropylimine (DIPI) was used as a probe molecule to investigate the hydrogenation of C N on the Ni/Al2O3, Ni/LaAlO and Ni/LaOx catalysts. Microcalorimetric adsorption and infrared spectroscopy were applied to determine the surface bond strengths and structures of the reactant and product. It was found that the acidic support favored the adsorption and activation of DIPI and H2 on Ni, leading to the increased activity (TOF) for the hydrogenation of DIPI, while the basic support promoted the dehydrogenation of the amine product on Ni, being unfavorable for the hydrogenation of DIPI. In particular, the conversion of DIPI was significantly increased when isopropanol (IPA) was used as a solvent, due to the hydrogen transfer reaction (HTR) between IPA and DIPI, which was further evidenced by the infrared spectrum of co-adsorbed IPA and DIPI.

In this study, we synthesized a class of positional isomers by attaching a carboxylic group in different sites (para-, meta- and ortho-position) of an aromatic core. The isomers undergo both aggregation-induced emission (AIE) and intramolecular charge transfer (ICT) mechanisms, as proved by their photoluminescence (PL) behaviour. Changing the position of the carboxylic group will adjust the dipole–dipole direction, which further controls the self-assembled architecture: The morphology undergoes a transition from 1D nanowire to 2D microsheet, and even to 3D microcube. The benzoic acid moiety of the AIE isomers has strong affinity to amines, and adsorbing amines leads to spectral changes including hypochromatic shift and emission quenching. The sensing mechanism was studied by density functional theory (DFT), which reveals that the amine-responsive fluorescence can be ascribed to the weakened ICT effect. A prototype of amine sensor based on m-DB self-assemblies was developed accordingly, showing a remarkable quenching efficiency as high as 85.4%. A linear relation was obtained from the quantitative determination of amine, offering a low detection limit of 2.02 Pa. It can also respond to other organic amines such as diisopropylamine (DIPA), triethylamine (TEA), isopropylamine (IPA) and cyclohexylamine (CHA). Finally, the practicality of the sensor was also demonstrated: When placing the sensing film beside the spoiled meat, the spectrum shows a remarkable fluorescence quenching; in contrast, fresh meat samples have induced a much lower quenching efficiency. This demonstrates that the AIE isomers have a great potential to serve as indicators for meat spoilage.

A novel method to access 1,1-diarylalkanes from readily available, nonactivated alkyl bromides and aryl bromides via visible-light-driven nickel and iridium dual catalysis, wherein diisopropylamine (iPr2NH) is used as the terminal stoichiometric reductant, is reported. Both primary and secondary alkyl bromides can be successfully transformed into the migratory benzylic arylation products with good selectivity. Additionally, this method showcases tolerance toward a wide array of functional groups and the presence of bases.

The search for less time-consuming and inexpensive methods for the synthesis of disulfides continues to be a hot subject of research. Herein, we report that diisopropylamine (iPr2NH) can act as a very effective catalyst for this process. The oxidative coupling of aryl thiols was carried out in the presence of catalytic amount ofiPr2NH in air (room temperature) in acetonitrile, without metal catalyst, additives, or external activators. This procedure opens a low-cost, green, and industrially applicable synthetic pathway to obtain aryl disulfides.

Densities (ρ) and speeds of sound () were measured for the binary mixtures formed by ethyl lactate with n-propylamine, diisopropylamine, dipropylamine and tripropylamine mixtures at temperatures (3...

The Pd-catalyzed selective hydrogenation of C C double bond in (3,3-diphenylallyl)diisopropylamine or 3,3-diphenylallyl alcohol was evaluated using different catalytic systems [Pd/C, Pd(OAc)2/ionic liquid, isolated Pd(0) nanoparticles]. For the (3,3-diphenylallyl)diisopropylamine, hydrogenolysis is preferred over hydrogenation, and only moderate selectivities were obtained for the desired product. However, complete conversion and 100% selectivity were obtained for the hydrogenation of 3,3-diphenylallyl alcohol using isolated Pd(0) nanoparticles under mild condition. This successful strategy enabled the effective synthesis of diisopromine and feniprane drugs and opens new possibilities for the preparation of other biologically active compounds.

Organic molecular ferroelectric diisopropylammonium chloride (dipaCl) was successfully synthesized using diisopropylamine, hydrochloric acid (57%) and methanol solution. Dielectric permittivity, impedance, modulus spectroscopy and conductivity were systematically studied by Capacitance–Conductance ([Formula: see text] – [Formula: see text] measurements in the temperature range of 373–445 K. Dielectric property tests clearly show that the organic molecular ferroelectric dipaCl obeys Curies–Weiss law 1/[Formula: see text] = ([Formula: see text]–[Formula: see text]/[Formula: see text]. The real ([Formula: see text] and imaginary ([Formula: see text]) parts of the electrical modulus were calculated from the various values of [Formula: see text] and [Formula: see text]. It is shown that AC conductivity satisfies the relation [Formula: see text], where the power exponent [Formula: see text] depends on temperature and frequency. From Arrhenius equation, the activation energies [Formula: see text]and [Formula: see text] are also calculated which describes the complete conduction mechanism of dipaCl.

Cocrystallization of the commonly available organic amine, diisopropylamine, with a series of carboxylic acids gave a total of sixteen molecular salts with the compositions: diisopropylaminium 2-methyl-2-phenoxypropanate [(Hdpa)+ · (mpa−), mpa− = 2-methyl-2-phenoxypropanoate] (1), diisopropylaminium 2-methyl-2-(naphthalen-2-yloxy)-propionate [(Hdpa)+ · (npa−), npa− = 2-methyl-2-(naphthalen-2-yloxy)-propionate] (2), diisopropylaminium indole-3-acetate [(Hdpa)+ · (iaa−), iaa− = indole-3-acetate] (3), diisopropylaminium 4-chlorophenoxyacetate [(Hdpa)+ · (cpa−), cpa− = 4-chlorophenoxyacetate] (4), diisopropylaminium 2,4-dichlorophenoxyacetate [(Hdpa)+ · (dcpa−), dcpa− = 2,4-dichlorophenoxyacetate] (5), diisopropylaminium 4-hydroxybenzoate [(Hdpa)+ · (hba−), hba− = 4-hydroxybenzoate] (6), diisopropylaminium 4-aminobenzoate [(Hdpa)+ · (aba−), aba− = 4-aminobenzoate] (7), tetra(diisopropylaminium) tetra(1-hydroxy-2-naphthoate) trihydrate [(Hdpa)44+ · (2-hnpa)44− · 3H2O, 2-hnpa = 1-hydroxy-2-naphthoate] (8), diisopropylaminium 2-hydroxy-3-naphthoate [(Hdpa)+ · (3-hnpa-), 3-hnpa- = 2-hydroxy-3-naphthoate] (9), diisopropylaminium 5-bromosalicylate [(Hdpa)+ · (bsa−), bsa− = 5-bromosalicylate] (10), diisopropylaminium 3,5-dinitrobenzoate [(Hdpa)+ · (dna−), dna− = 3,5-dinitrobenzoate] (11), diisopropylaminium 3,5-dinitrosalicylate [(Hdpa)+ · (3,5-dns-), 3,5-dns- = 3,5-dinitrosalicylate] (12), tetra(diisopropylaminium) bis(m-phthalate) monohydrate [(Hdpa+)4 · (mpta2−)2 · H2O, mpta2− = m-phthalate] (13), bis(diisopropylaminium) dihydrogen 1,2,3,4-butane tetracarboxylate [(Hdpa+)2 · (H2Bta2−), H2Bta2− = dihydrogen 1,2,3,4-butane tetracarboxylate] (14), bis(diisopropylaminium) mucate [(Hdpa+)2 · (muc2−), muc2− = mucate] (15), and diisopropylaminium hydrogen 1,2-phenylenediacetate [(Hdpa) · (Hpda−), Hpda− = hydrogen 1,2-phenylenediacetate] (16). The sixteen salts have been characterised by XRD technique, IR, and elemental analysis, and the melting points of all the salts were also reported. And their structural and supramolecular aspects are fully analyzed. The result reveals that among the sixteen investigated crystals the NH groups in the diisopropylamine are protonated when the carboxylic acids are deprotonated, and the crystal packing is interpreted in terms of the strong charge-assisted N H⋯O hydrogen bond formation between the ammonium and the deprotonated COOH groups. Except the N H⋯O hydrogen bond, the O H⋯O hydrogen bonds (charge assisted or neutral) were also found at the salts 6, 8, 9, 10, 12, 13, 14, 15, and 16. Further analysis of the crystal packing of the salts indicated that a different family of additional CH O/CH2 O/CH3 O, CH-π/CH3-π, CH3-Cπ, N-π, and π-π associations contribute to the stabilization and expansion of the total structures. For the coexistence of the various weak interactions these structures adopted homo or hetero supramolecular synthons or both.

One of the main obstacles that hamper the application of zeolites is the high consumption of expensive structure-directing agent. Herein, we reported the mechanochemisty-mediated solventless synthesis of AlPO4-11 aluminophosphate molecular sieve with low dosage of diisopropylamine (DIPA) as the structure-directing agent. The influences of DIPA/Al2O3 ratio, fluoride ions, seed crystals and high-energy mechanochemical pretreatment on the synthesis of AEL-type zeolite were investigated in detail. Both DIPA and fluoride ions are indispensable for the successful synthesis of AEL phase. The resultant AEL molecular sieves were characterized by XRD, SEM, TG-DTA, CHN elements analysis, and N2 physisorption. The results indicate that the introduction of seed crystals cannot improve the phase purity and crystallinity of the resulting products. On the other hand, high-energy mechanochemical pretreatment not only can affect the morphology of AEL zeolite, but more importantly, can also reduce the consumption of structure-directing agent.

This paper presents the experimental measurements of densities, ρ , viscosities, η and speeds of sound, u of (Diisopropylamine (DIIPA) + 1-Hexanol, + 1-Octanol, + 1-Decanol) over the entire composition range at (293.15 to 313.15) K and atmospheric pressure. We examined the influence of temperature and alcohol chain length upon the various studied properties. Negative values of excess molar volume V m E and excess molar isentropic compressibilities, K S , m E indicates the presence strong intermolecular interactions. The results of deviations in speeds of sound, u D , viscosity deviations, Δ η and Gibbs excess free energy of activation of viscous flow, Δ G ⁎ E also supports the conclusion drawn from V m E and K S , m E . The outcomes of V m E have been correlated to Prigogine –Flory –Patterson theory (PFP).

Manganese-rich MnSAPO-34 molecular sieves were prepared by one-pot synthesis method for NO x abatement using the ammonia-selective catalytic reduction (NH3-SCR) technology and characterized using ICP, BET, XRD, FE-SEM, H2-TPR, NH3-TPD, XPS, and DR UV-Vis analyses. The experimental results indicate that the Mn content and chemical state, as well as the surface acidity, of the MnSAPO-34 molecular sieves significantly enhance their DeNO x efficiency at low temperatures (ca. 200–300 °C). The manganese-rich MnSAPO-34 was synthesized using a combination of triethylamine and diisopropylamine as the structural directing agents and high Mn loading (n(MnO)/n(P2O5) = 0.4). The resulting catalyst exhibits the highest activity among all of the samples with a NO x conversion value of nearly 95% and a N2 selectivity that is higher than 90% at 220–400 °C. In addition, this catalyst presents higher NO x conversion than the conventional V2O5-WO3/TiO2 catalysts and other SAPO-based catalysts below 300 °C. Furthermore, the analytical results indicate that the manganese species in the catalyst are mainly in the form of a framework Mn(IV), which could play a significant role in the NH3-SCR process as the specific active species. The results suggest that controlling the types and content of the organic amine templates and variations in the surface acidity of the catalysts may significantly enhance the SCR activity at lower temperatures.