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Four new diacid amides of dicholesteryl l-phenylalaninate were designed and prepared. The compounds with spacers containing three, four, five, or six carbon atoms are denoted as 1–4, respectively. Gelation tests showed that the four compounds are versatile organogelators, and a subtle change in the length of the spacer can produce a dramatic change in the gelation behaviors of the compounds, as well as the micro-structures of the gel networks as revealed by SEM and XRD measurements. Within the 77 gel systems studied, at least seven of them, including 2/kerosene, 2/toluene, 2/xylene, 3/kerosene, 3/1-pentanol, 3/1-hexanol and 3/1-heptanol, gel spontaneously at room temperature. Furthermore, 2and 3can be used for the selective gelation of xylene or kerosene from their mixtures with water. Importantly, heating and cooling cycle or addition of a co-solvent is not necessary for the selective gelation. Furthermore, the gels of 2/xylene are mechanically strong enough for separation, and thereby it is believed that 2is a strong candidate for the practical separation of xylene from its mixture with water. FT-IR and temperature-dependent 1H NMR measurements demonstrated that inter-molecular hydrogen bonding plays an important role for the formation and maintenance of the gel networks. [ABSTRACT FROM AUTHOR]

Dimethyl sulfoxide is a widely used solvent in organic synthesis and in the pharmaceutical industry because of its low cost, stability, and low toxicity. Multicomponent reactions are an advanced approach that has become an efficient, economical, and eco-friendly substitute for the conventional sequential multi-step synthesis of various biologically active compounds. This approach was adopted for the synthesis of previously unknown 2-(2,4-diamino-3-cyano-5H-chromeno[2,3-b]pyridin-5-yl)malonic acids via transformation of salicylaldehydes, malononitrile dimer, and malonic acid. It was shown that the use of DMSO at room temperature makes it possible to synthesize previously unavailable compounds. The investigation of the reaction mechanism using 1H-NMR monitoring made it possible to confirm the proposed mechanism of the transformation. The structure of synthesized 5H-chromeno[2,3-b]pyridines was confirmed by 2D-NMR spectroscopy. [ABSTRACT FROM AUTHOR]

Abstract: A series of novel fluorinated poly(aryl ether)s containing phthalazinone moieties (FPPEs) have been prepared by a modified synthetic procedure for optical waveguide applications. The obtained random copolymers exhibited excellent solubility in polar organic solvents, high glass transition temperatures (T gs: 185–269°C), good thermal stabilities (the temperatures of 1% weight loss: 487–510°C) and good optical properties. By adjusting the feed ratio of the reactants, the refractive indices of TE and TM modes (at 1550nm) could be well controlled in the range of 1.575–1.498 and 1.552–1.484, respectively. The optical losses of the FPPEs exhibited relatively low values (less than 0.27dB/cm at 1310nm). Additionally, the thermo-optic coefficient (dn/dT) values of the FPPEs at 1310nm and 1550nm (TE mode) ranged from −0.97×10−4 °C to −1.33×10−4 °C and from −0.96×10−4 °C to −1.29×10−4 °C, respectively. [Copyright &y& Elsevier]

Biodiesel synthesis by alcoholysis of three vegetable oils (soybean, sunflower and rice bran) catalyzed by three commercial lipases (Novozym 435, Lipozyme TL-IM and Lipozyme RM-IM), and the optimization of the enzymes stability over repeated batches is described. The effects of the molar ratio of alcohol to oil and the reaction temperature with methanol, ethanol, propanol and butanol were also studied. All three enzymes displayed similar reaction kinetics with all three oils and no significant differences were observed. However, each lipase displayed the highest alcoholysis activity with a different alcohol. Novozym 435 presented higher activity in methanolysis, at a 5:1 methanol:oil molar ratio; Lipozyme TL-IM presented higher activity in ethanolysis, at a 7:1 ethanol:oil molar ratio; and Lipozyme RM-IM presented higher activity in butanolysis, at a 9:1 butanol:oil molar ratio. The optimal temperature was in the range of 30-35 °C for all lipases. The assessment of enzyme stability over repeated batches was carried out by washing the immobilized enzymes with different solvents (n-hexane, water, ethanol, or propanol) after each batch. When washing with n-hexane, approximately 90% of the enzyme activity remained after seven synthesis cycles. [ABSTRACT FROM AUTHOR]

Herein we report a study involving the homogeneous catalytic reduction of unsaturated substrates in aqueous solutions or water-organic solvent mixtures. The reduction of olefins has been carried out in the presence of catalytic amounts of [Fe(CN)5NH3]3- and excess of NH2OH, which under mild reaction conditions can be used to reduce carbon-carbon unsaturations without affecting carbonyl functionalities and aromatic rings. To explore the scope of the catalytic reduction, a wide variety of representative unsaturated substrates have been examined. The steric effects of the substituents on the carbon-carbon multiple bond as well as the regioselectivity and stereoselectivity of the catalyst have been studied. The deuterium kinetic isotope effect on the catalytic reduction of double bonds in olefins has been analyzed, and no significant kinetic isotope effect was found. Among the great advantages of this novel procedure for catalytic reduction are that hydrogen and high pressures are not needed, the catalyst is inexpensive and easily prepared, and water as well as water-organic solvent mixtures can be used as reaction media. [ABSTRACT FROM AUTHOR]

Abstract: The synthesis of novel, symmetrical, hexadecasubstituted phthalocyaninatozinc(II) bearing eight, fluorinated phenoxy groups in peripheral positions and eight, non-peripheral hexyloxy groups as well as their related unsymmetrical derivatives is described. The compounds were characterized by 1H NMR, GC–MS, UV–vis and IR. The synthesized ZnPc complexes possess excellent solubility in various organic solvents such as CH2Cl2, THF, acetone and ethyl acetate and do not readily aggregate in solution. The new complexes show interesting luminescence properties in different organic solvents. [Copyright &y& Elsevier]

Sialylation reactions using a new sialyl donor, diethyl 5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-2-O-β-D-glycero-D-galacto-2-nonulopyranosylonarflide phosphite (Neu5Ac-1-amide-2-phosphite) derivatives, and the synthesis of the sialyl-TN-MUC4 glycopeptide are described. The sialylation was performed in CH2Cl2 solvent toward the 6-hydroxyl group of several monosugar acceptors and generated α-sialoside in good yield under low temperature and TMSOTf activation system. Amide derivatives of sialoside were easily converted into naturally occurring sialoside after hydrolysis of the amide group. Sialyl-β(2,6)-GalN3 was also prepared by this new sialylation protocol, and then this sialoside was further converted into a Fmoc-protected sialyl-TN serine derivative for solid-phase glycopeptides synthesis. The solid-phase glycopeptide synthesis using this sialyl-TN serine derivative in which the sugar hydroxyl group was free afforded the target sialyl-TN-MUC4 glycopeptide. [ABSTRACT FROM AUTHOR]

The preparation of N-methylpyrazoles is usually accomplished through reaction of a suitable 1,3-diketone with methylhydrazine in ethanol as the solvent. This strategy, however, leads to the formation of regioisomeric mixtures of N-methylpyrazoles, which sometimes are difficult to separate. We have determined that the use of fluorinated alcohols such as 2,2,2-trifluoroethanol (TFE) and 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) as solvents dramatically increases the regioselectivity in the pyrazole formation, and we have used this modification in a straightforward synthesis of fluorinated analogs of Tebufenpyrad with acaricide activity. [ABSTRACT FROM AUTHOR]

Paal-Knorr condensation of 2,5-hexadione with primary amines in the presence of a catalytic amount of sulfamic acid under solvent-free conditions has been accomplished with an excellent yield. This is a very easy, rapid, and high-yielding reaction for the synthesis N-substituted pyrrole derivatives. [ABSTRACT FROM AUTHOR]

Alum [KAl(SO4)2?12H2O] was found to be an efficient, non-toxic, cheap, and environmentally benign catalyst for the synthesis of 1,5-benzodiazepines, in good to excellent yields, from the condensation of 1 mole of o-phenylenediamine with 2 moles of ketone under solvent-free conditions. [ABSTRACT FROM AUTHOR]

Ionic liquids are liquids composed completely of ions. In the past two decades, ionic liquids have been widely used as “green solvents” replacing traditional organic solvents for organic synthesis and catalysis. In addition, ionic liquids are playing an increasingly important role in separation science. In this Account, the application of ionic liquids in all areas of separation science including extractions, gas chromatography, and supported liquid membrane processes are highlighted. [ABSTRACT FROM AUTHOR]

Three urea-based aromatics 1-3, each with distinct steric and electronic characteristics, have been synthesized and their ability to undergo hierarchical assembly and gel organic solvents investigated. We have found that compound 1 promotes the sol-gel phase transition in primary alcohols (from CH3OH to C10H21OH; CGC < 15 mg/mL), while 2 and 3 do not. IR spectroscopy, X-ray powder diffraction (XRPD), and transmission electron microscopy (TEM) measurements show that 1 organizes into "cylinders" in primary alcohols, using three-centered hydrogen bonds and π-π aromatic interactions. The cylinders further organize into pairs through interdigitation of the methyl groups of the adjacent aromatic rings. Importantly, the lateral packing of the cylinders is enhanced as the bulk solvent polarity increases providing a mechanism for controlling the material's morphology via the solvophobic effect. Molecular mechanics (Amber) and semiempirical (AM1) calculations suggested similar conformational behavior but distinct electronic properties of 1-3. Thus, π-deficient 2 without the methyl groups and π-rich 3 without aromatic nitrogen fail to promote the sol-gel phase transition in alcohols due to their inability to undergo effective hierarchical assembly, which is necessary for the formation of a 3D fibrillar network. In addition, we have found that the ultrasonication of a supersaturated solution of 1 is necessary for the gelation. Presumably, a fast exchange of the aggregates of 1 is assisted with sonic waves to allow for the effective and "error free" assembly wherein an entangled net of fibers capable of encapsulating solvent molecules is formed. [ABSTRACT FROM AUTHOR]

Conformationally preorganized C3-symmetric polypyridine hosts were designed to recognize monosaccharides in organic solvent through complementary intermolecular hydrogen bonds. Hydrogen bonding acceptor sites are introduced to the host in a systematic way to evaluate the effect of a H-bond number for carbohydrate recognition. The degree of affinity was adjustable by the number of hydrogen bonding acceptors in the peripheral pyridine unit. The anomeric and diastereomeric selectivities were observed to be moderate to high. Molecular modeling studies and 1H NMR titration data reveal that these conformationally well-defined receptors bind to the carbohydrates through multiple intermolecular hydrogen bonds. [ABSTRACT FROM AUTHOR]

The reaction of 1-formyldipyrromethane (100 mM) in toluene at 115 °C containing DBU (10 mol equiv) and MgBr2 (3 mol equiv) in the presence of air affords the magnesium chelate Mg(II) porphine in 30-40% yield. The advantages of the new method include simplicity, high concentration, chromatography-free purification, gram-scale synthesis, and avoidance of the poorly soluble free base porphine. Mg(II) porphine exhibits good solubility in common organic solvents and is a valuable core scaffold for derivatization. [ABSTRACT FROM AUTHOR]

Abstract: Over the last few years, there has been a dramatic increase in the number of publications in the field of lipase-catalyzed reactions performed in common organic solvents, ionic liquids or even non-conventional solvents. A fairly large percentage of these publications have emerged from organic chemists who have recognized the potential of biocatalysis as a viable and popular technique in organic synthesis. Considerable research has shown that reactions catalyzed by enzymes are more selective and efficiently performed than many of their analogues in the organic chemistry laboratory. This review article focuses on some of the recent developments in the rapidly growing field of lipase-catalyzed asymmetric access to enantiomerically pure/enriched compounds. The literature search is dated back to the last five years and covers some comprehensive examples. [Copyright &y& Elsevier]

Perfluoroisopropyl carbanions generated in situ by treatment of perfluoropropene (HFP) with solid KF in the appropriate solvents add to N-alkylpyridinium, quinolinium, and other azinium salts to give reasonably stable N-alkyldihydroazines containing a perfluoroisopropyl group. In most cases, addition proceeds in position 2 of the heterocyclic ring. Stability of these dihydroazines depends on the nature of the N-alkyl group and other substituents present in the azine ring. The least stable of them were converted into their stable C-trifluoroacetyl derivatives in reaction with trifluoroacetic anhydride. Treatment of N-benzyl- or N-p-methoxybenzyl-2-perfluoroisopropyl dihydroazines with oxidizing agents such as DDQ or cerium(IV) ainmonium nitrate results in cleavage of the benzylic C—N bond followed by oxidation of the ring, giving pyridines or quinolines with a perfluoroisopropyl group in the aromatic ring. On the basis of these findings, a new protocol for introduction of perfluoroalkyl substituents into azine rings was elaborated via oxidative nucleophilic substitution of hydrogen. It involves three chemical steps: (i) alkylation of azine with p-MeOC6H4CH2Br, (ii) reaction of the resulting salt with fluorinated carbanions generated in situ from I-IFP and KF, and (iii) N-deprotection and aromatization of the isolated dihydroazine on treatment with CAN. The first two reactions, (i) and (ii), can be performed as a one-pot operation. [ABSTRACT FROM AUTHOR]

Abstract: A task-specific basic ionic liquid, [Bmim]OH, has been introduced as a catalyst for the aza-Michael addition of aromatic amines and N-heterocycles to cyclic or acyclic ketones under neat conditions. The catalyst can be recycled for subsequent reactions without any appreciable loss of efficiency. [Copyright &y& Elsevier]

Glycosylation of 6-(substituted-imidazol-1-yl)purine sodium salts with 2-deoxy-3,5-di-O-(p-toluoyl)-α-D-erythro-pentofuranosyl chloride proceeds with regiospecific formation of the N9 isomers. Base substrates with lipophilic substituents on the C6-linked imidazole moiety are more soluble in organic solvents, and the solubility is further increased with binary solvent mixtures. Selective solvation also diminishes the extent of anomerization of the chlorosugar. Stirred reaction mixtures of the modified-purine sodium salts generated in a polar solvent and cooled solutions of the protected 2-deoxysugar chloride in a nonpolar solvent give 2′-deoxynucleoside derivatives with N9 regiochemistry and enhanced β/α configuration ratios. Application of the binary-solvent methodology with 2-chloro-6-(substituted-imidazol-1-yl)purine salts in cold acetonitrile and the chlorosugar in cold dichloromethane gives essentially quantitative yields of the N9 isomers of β-anomeric 2′-deoxynucleoside intermediates. Direct ammonolysis (NH3/MeOH) of such intermediates or benzylation of the imidazole ring followed by milder ammonolysis of the imidazolium salt gives high yields of the clinical anticancer drug cladribine (2-chloro-2′-deoxyadenosine). [ABSTRACT FROM AUTHOR]

Abstract: Pullulan acetate (AcPL) with various degree of substitution (DS: 1.0–3.0) was synthesized by the reaction of pullulan with acetyl chloride in the presence of pyridine. The product was characterized by gel permeation chromatography (GPC), infra-red (IR) and 1H NMR spectroscopy. The weight average molecular weights of the products did not decrease less than 190,000 (GPC) in the acetylation reaction. Thermogravimetric analysis (TGA) revealed that AcPL has a higher decomposition temperature (306–363°C) than unmodified pullulan (295°C). Differential scanning calorimetry analysis (DSC) revealed that all the AcPLs exhibit a clear T g, which decreased with increasing DS value in the range of DS 1.0–2.4. The AcPL with DS 2.4 showed the lowest T g (153°C), and the AcPL with DS 3.0 had a slightly higher T g (163°C). Tensile modulus of AcPL films was comparable to that of a popular cellulose acetate film. The biodegration rate of AcPL decreased with increasing degree of acetylation. The AcPL with DS 3.0 was found to form a semi-clear gel in organic solvents such as dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), and 1,4-dioxane. [Copyright &y& Elsevier]

Abstract: The enzymatic resolution of (RS)-methyl mandelate with n-butylamine using lipases in organic solvents (n-hexane, tert-butanol, and chloroform) and ionic liquids [BMIm][BF4] and [BMIm][PF6] is reported. The amide configuration is dependent on the organic solvent. When using mixtures of chloroform or tert-butanol/ionic liquids (10:1 v/v) with CAL-B as the catalyst, the amides were obtained in high enantiomeric excess (eep >99% and E >200). [Copyright &y& Elsevier]

Abstract: The synthesis and chemical polymerization of a thiophene disubstituted with an alkylic and an ω-bromine functionalized oligomethylenic chain is described. The obtained polymer, namely the poly[3-hexyl-4-(6-bromohexyl)thiophene], is completely soluble in common organic solvents and its structural, thermal and chemical–physical properties are compared with those of a ‘conventional’ bromohexyl 3-substituted polythiophene. The new polymer may be considered as a key-intermediate for the synthesis of multifunctional soluble polythiophenes since its self-plastifying feature may permit the insertion on the polymeric side-chains, by simple post-polymerization functionalization reactions, of sterically demanding or strongly interacting functional groups, without final solubility being compromised. [Copyright &y& Elsevier]

1-Acyldipyrromethanes are important precursors in rational syntheses of diverse porphyrinic compounds. 1-Acyldipyrromethanes are difficult to purify, typically streaking upon chromatography and giving amorphous powders upon attempted crystallization. A solution to this problem has been achieved by reacting the 1-acyldipyrromethane with a dialkylboron triflate (e.g., Bu2B-OTf or 9-BBNOTf) to give the corresponding B,B-dialkyl-B-(1-acyldipyrromethane)boron(III) complex. The reaction is selective for a 1-acyldipyrromethane in the presence of a dipyrromethane. The 1-acyldipyrromethane-boron complexes are stable to routine handling, are soluble in common organic solvents, are hydrophobic, crystallize readily, and chromatograph without streaking. The 1-acyldipyrromethane can be liberated in high yield from the boron complex upon treatment with 1-pentanol. Alternatively, the 1-acyldipyrromethane-boron complex can be used in the formation of a transA2B2-porphyrin. In summary, the boron-complexation strategy has broad scope and greatly facilitates the isolation of 1-acyldipyrromethanes. [ABSTRACT FROM AUTHOR]

Optically active aliphatic ω-hydroxycyanohydrins are valued materials in organic synthesis. We describe herein the effect of the different reaction parameters as organic solvent, temperature, concentration of enzyme or concentration of buffer in the (R)-oxynitrilase-catalyzed synthesis of optically enriched aliphatic ω-hydroxycyanohydrins from 4-hydroxybutanal and 5-hydroxypentanal. [Copyright &y& Elsevier]

A novel monomer, (trans)-7-[4-N,N-(di-β-hydroxyethyl) amino-benzene]-ethenyl-3,5- dinitrothiophene (HBDT), and the corresponding prepolymer, polyurethane were synthesized and characterized. The details of synthesis of the monomer and its further polymerization were presented. The prepolymer and polyurethane exhibited good thermal stability and good solubility in common organic solvents. The d33 coefficient of the poled films was determined to be 40.3 pm/V. [ABSTRACT FROM AUTHOR]

Deep Eutectic Systems (DESs) are obtained by combining Hydrogen Bond Acceptors (HBAs) and Hydrogen Bond Donors (HBDs) in specific molar ratios. Since their first appearance in the literature in 2003, they have shown a wide range of applications, ranging from the selective extraction of biomass or metals to medicine, as well as from pollution control systems to catalytic active solvents and co-solvents. The very peculiar physical properties of DESs, such as the elevated density and viscosity, reduced conductivity, improved solvent ability and a peculiar optical behavior, can be exploited for engineering modular systems which cannot be obtained with other non-eutectic mixtures. In the present review, selected DESs research fields, as their use in materials synthesis, as solvents for volatile organic compounds, as ingredients in pharmaceutical formulations and as active solvents and cosolvents in organic synthesis, are reported and discussed in terms of application and future perspectives. [ABSTRACT FROM AUTHOR]

Thus far, emulsion-templated macroporous hydrogels have mostly been produced as monolithic blocks corresponding to the dimensions of the polymerization vessel, while the number of examples of other shapes and dimensions is as yet fairly small. In this article, we report on the double-emulsion-templated synthesis of spherical, cross-linked polyelectrolyte-based hydrogel beads through the sedimentation polymerization of oil-in-water-in-oil (O/W/O) high internal phase emulsions (HIPEs). When a mixture of 2-acrylamido-2-methyl-1-propanesulfonic acid or (3-acrylamidopropyl)-trimethylammonium chloride (AMPS or AMPTMA, ionic monomers) and acrylamide (AAM, a nonionic monomer) was used, the sedimentation polymerization of O/W/O HIPEs resulted in spherical polymerized high internal phase emulsions (polyHIPE) copolymer beads with a throughout open macroporous morphology. A combination of three-dimensionally-interconnected macroporous morphology and small spherical size remarkably improves the swelling and water absorption properties of the beads as dry beads swell to near-equilibrium size within seconds as opposed to hours in the case of monolithic blocks. PolyHIPE beads have a hygroscopic character due to their inherent charges within the macroporous framework. Therefore, the throughout porous morphology and charged functionality of the polyelectrolyte polyHIPE beads allow reversible and rapid water absorption from the tested organic solvents with a water removal efficiency of up to 95%. This work opens a new path to polyHIPE hydrogel engineering, with extremely fast water-absorption capability, which may have promising applications in various fields such as agriculture, horticulture, hygiene products, and daily chemicals. Image 1 • Double-emulsion-templated synthesis of polyelectrolyte-polyHIPE beads is reported. • Macroporous beads showed an impressively fast swelling rate. • The equilibrium water absorption can be reached in only 15 s. • The hygroscopic character has proven to be advantageous in organic solvents drying. [ABSTRACT FROM AUTHOR]

Abstract: Multi-component synthesis of 2-amino-3,5-dicarbonitrile-6-thio-pyridines has been developed by using the reaction of aldehydes, malononitrile, and thiophenols in the presence of a Zn(II) or a Cd(II) metal–organic framework (MOF) as the heterogeneous catalyst. This protocol tolerates different functional groups on the substrates and does not require the use of any organic solvent. Moreover, the Zn(II) and Cd(II) MOF catalysts can be recovered and reused for a number of runs without loss of activity. [Copyright &y& Elsevier]

Abstract: 2-Amino-4-arylthiazoles were prepared in a one-pot solvent-free procedure by reaction of p-substituted acetophenones with thiourea and iodine under microwave irradiation. [Copyright &y& Elsevier]

Aldehydes or ketones react readily in one-pot with isatoic anhydride and ammonium salts in the presence of tris(hydrogensulfato)boron to produce the corresponding 2,3-dihydroquinazolin-4(1H)-ones in high yields under solventfree conditions. The use of tris(hydrogensulfato)boron makes this process quite simple, more convenient and environmentally friendly. 2,3-Dihydroquinazolin-4(1H)-one derivatives have interesting biological and pharmacological activities. [ABSTRACT FROM AUTHOR]

Abstract: Nitrocylcohexadienones have been applied as nitration reagents for mild, mono-nitrating reactions. The original synthesis of 2,3,5,6-tetrabromo-4-methyl-4-nitrocylcohexa-2,5-dien-1-one appeared to be difficult to pursue due to both the solvent system and reaction conditions. Therefore, we applied a modified solvent system and optimized the reaction conditions to prepare the dienone at 0°C, to eventually overcome the difficulties. [Copyright &y& Elsevier]

Abstract: In this Letter we present the synthesis of hitherto unreported 1-aryl-2-alkyl-1,4,5,6,7,8-hexahydro-1,3-diazocines 1. Cyclic amidines 1 were synthesized by PPSE promoted ring closure of N-acyl-N′-arylpentamethylenediamines 2. The cyclodehydration reaction was performed under microwave irradiation in solvent-free conditions. Precursors 2 were prepared by selective functionalization of N-arylcadaverines 3. [Copyright &y& Elsevier]

Abstract: An efficient and general method has been described for the synthesis of 3-hydroxy-3-(nitromethyl)indolin-2-one by the reaction of isatins with nitromethane/nitroethane in the presence of DABCO. The reaction is catalytic, very rapid, yields are very high and avoids the use of solvents for reaction. The protocol is applicable for substituted isatins as well as substituted nitroalkanes. [Copyright &y& Elsevier]

Abstract: Baker’s yeast catalyzed one-pot three-component cyclocondensation of aryl aldehydes, malononitrile, and β-dicarbonyls in organic medium has been carried out to obtain polyfunctionalized 4H-pyrans. The reaction has been carried out at room temperature in organic solvent, dimethylacetamide and the products obtained in good to moderate yields with simple work up procedure. [Copyright &y& Elsevier]

Abstract: A novel task-specific ionic liquid, 1-butyl-3-methylimidazolium p-toluenesulfinate, [bmim][p-TolSO2] has been synthesized and used as a nucleophile for the reaction with alkyl bromides and phenacyl bromides to prepare sulfones and β-ketosulfones in excellent yields (80–93%) in [bmim][BF4] ionic liquid. The isolated yields of sulfones and β-ketosulfones were higher in [bmim][BF4] than other organic solvents at room temperature. [Copyright &y& Elsevier]

Abstract: Convenient simple and suitable methods for the synthesis of carbamates, N,N′-unsymmetrically disubstituted ureas, and S-alkyl thiocarbamates derived from CH3OC(O)SNCO in one-step are provided. Reactions are operationally simple and have high selectivity toward nitrogen, oxygen, and sulfur nucleophiles. The absence of solvents coupled with high yields and short reaction times make these procedures very attractive for synthesis. [Copyright &y& Elsevier]

Abstract: The synthesis of 2,6-bis-hydrazonopyridines from 2,6-bis-hydrazinopyridine and the conversion of these bis-hydrazones into 2,6-bis-indazol-1-ylpyridines were studied. The conversion of bis-haloarylhydrazones to bis-indazoles was systematically optimized using iron and copper mediated reactions and various bases and ligands. By varying solvent, base, transition metal, and ligand, a novel regiospecific route to the 2,6-bis-indazol-1-ylpyridine class of ligands was developed. [Copyright &y& Elsevier]

Abstract: A simple and efficient trans-acetoacylation method for the synthesis of β-keto ester derivatives has been described using ytterbium(III) triflate as a new catalyst under solvent-free condition. This method was found to be efficient and convenient for the synthesis of a wide variety of β-keto ester derivatives. [Copyright &y& Elsevier]

Abstract: An efficient one-pot method has been developed for the synthesis of α-oxycarbanilinophosphonates via a one-pot reaction of an aldehyde with diethyl phosphite in the presence of magnesium oxide followed by reaction with an isocyanate under solvent-free conditions using ultrasonic irradiation. This method is simple, rapid and good yielding. [Copyright &y& Elsevier]

A high-throughput synthesis of crystalline silicon nanowires is reported using trisilane as a reactant with colloidal gold nanocrystals in a hot organic solvent. Nearly 80 mg of nanowire product is obtained in a 1 min reaction from a 10 mL reactor volume. Dodecylamine surface passivation is also demonstrated. [ABSTRACT FROM AUTHOR]

Special asymmetric crystallization of porous framework materials from achiral precursors under urothermal conditions is successfully achieved by using an enantiopure liquid as a co-solvent and chirality induction agent, which provides a new strategy for the synthesis of homochiral porous materials containing only achiral building blocks. [ABSTRACT FROM AUTHOR]

Abstract: The solvent-free reaction of oligoethylene glycol diglycidyl ethers with dimercaptoethane in the presence of benzyltrimethylammonium hydroxide (Triton B) gave, via regiospecific epoxide opening reactions, dihydroxy dithiacrown ethers in excellent yields and in short reaction times. [ABSTRACT FROM AUTHOR]

A simple triethoxysilane appended bis(urea) low molecular weight gelator (LMWG) affords strong gels in organic solvents that are susceptible to fine tuning by anion binding, while the gel structure can be rigidified into a porous hybrid polymer material by hydrolysis of the triethoxysilane end groups. [ABSTRACT FROM AUTHOR]

In order to assemble supramolecular capsules, there is a need for reliable and effective synthetic methods for decorating cavitand-based host structures with appropriate functional groups. The synthesis of four different cavitands of significantly different depth and interior volume functionalized with four aldoxime groups capable of forming homomeric or heteromeric capsules through hydrogen bonding is reported. The final step in each synthesis, the aldehyde to oxime transformation, has been achieved in excellent yields through ‘solvent assisted grinding’. [ABSTRACT FROM AUTHOR]

In this study, we developed an efficient and selective iron-based catalyst system for the synthesis of ketones from secondary alcohols and carboxylic acids from primary alcohol. In situgenerated iron catalyst of thymine-1-acetate (THA) and FeCl3under solvent-free condition exhibits high activity. As an example, 1-octanol and 2-octanol were oxidized to 1-octanoic acid and 2-octanone with 89% and 98% yields respectively. [ABSTRACT FROM AUTHOR]

We present a proof-of-principle study of an environmentally-friendly approach to laboratory research, in which the synthesis and structural characterisation of metal–organic complexes and frameworks are achieved without using bulk solvents; our study addresses the use of heteroditopic ligands for manipulating the dimensionality of metal–organic materials and describes how kinetic obstacles in such mechanosynthesis can be overcome. [ABSTRACT FROM AUTHOR]

meso-Alkylidene (m-benzi)pentaphyrin containing exocyclic CC double bonds at two meso-positions is synthesized and fully characterized for the first time. The single crystal X-ray crystallographic analysis shows a concave conformation with two pyrrole rings inverted. The first protonation occurs exclusively at core nitrogen. The synthesized compound displays concentration dependent chromogenic responses for fluoride anion in organic solvent. [ABSTRACT FROM AUTHOR]

A general approach to transfer water-soluble nanoparticles with different shapes, sizes, and surface charges into organic solvents, retaining their surface charge properties was developed, and its application in fabrication of hybrid Janus particles with opposite charges in solution was also demonstrated. [ABSTRACT FROM AUTHOR]

A metal complex with a micelle-like, core–shell structure adopts higher nuclearity in water than in organic solvents, thereby imitating also the growth of a micelle, but through covalent rather than non-covalent aggregation. [ABSTRACT FROM AUTHOR]