“On-water” one-pot four-component synthesis of novel 1H-furo[2,3-c]pyrazole-4-amine derivatives

Research on Chemical Intermediates - A catalyst-free, simple and green protocol has been accomplished for the synthesis of novel 1H-furo[2,3-c]pyrazole-4-amines in a one-pot four-component domino...     

Surfactant-assisted synthesis of polyaniline nanofibres without shaking and stirring: effect of conditions on morphology and conductivity

Polyaniline (PANI) nanofibres were synthesised by the chemical oxidative polymerisation method using ammonium peroxydisulphate (APS) as an oxidant/initiator. In this work, a surfactant-assisted method without shaking and stirring was used for the synthesis of PANI nanofibres. The effect was investigated of various parameters such as monomer/oxidant ratio, polymerisation temperature, and the presence of surfactant (Triton X-100 as a non-ionic surfactant) on the morphology and electrical conductivity of nanofibres. The morphology of PANI nanofibres was characterised by scanning electron microscopy and transmission electron microscopy. The results demonstrate that the morphology of PANI nanofibres was significantly influenced by the aniline/APS mole ratio, polymerisation temperature and presence of the surfactant during synthesis. The results showed that more regular and consistent nanofibres were obtained using a monomer/oxidant ratio of 4 at ambient temperature of polymerisation. PANI nanofibres with diameters in the range of 10?C100 nm and length up to several ??m were obtained. PANI nanofibres were also characterised using FTIR and UV-VIS absorption spectroscopy. The electrochemical behaviour of PANI nanofibres was studied by cyclic voltammetry. It was found that the electrical conductivity of PANI nanofibres increased with the increasing monomer/oxidant ratio and decreasing polymerisation temperature, respectively.     

Efficient synthesis of α‐aminophosphonates via one‐pot reactions of aldehydes,amines, and phosphates in ionic liquid

Ionic liquids such as 1,3‐dialkylimidazolium bromides make excellent solvents for synthesis of α‐aminophosphonates from aldehydes, amines, and phosphites. The ionic liquids are successfully regenerated and reused. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 22:625–629, 2011; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20724     

A one-pot synthesis of functionalized ethyl 1,3-thiazole-5-carboxylates from thioamides or thioureas and 2-chloro-1,3-dicarbonyl compounds in an ionic liquid

Abstract  

A simple one-pot synthesis of functionalized ethyl 1,3-thiazole-5-carboxylates from the reaction of 2-chloro-1,3-dicarbonyl compounds with thioureas or thioamides in the presence of 1-butyl-3-methylimidazolium trifluoromethanesulfonate is described.     

A one-pot synthesis of alkyl acylcarbamodithioates from acid chlorides, thiols, and ammonium thiocyanate

Abstract  

An efficient synthesis of alkyl acylcarbamodithioates by reaction of acid chlorides with ammonium thiocyanate in the presence of thiols is described. The unusually large values of ⁵ J _FH = 12–15 Hz, observed for alkyl (2-fluorobenzoyl)carbamodithioates provide information about Ar–C–N–H torsion in these compounds.     

A new empirical rate equation for adsorption kinetics at solid/solution interface

It has been shown that most of the previously reported empirical rate equations for kinetics of adsorption at the solid/solution interface show high relative errors at the initial times of adsorption. In the present work we made a modification onto pseudo-first-order and pseudo-second-order models and presented a new empirical rate equation, called the modified pseudo-n-order (MPnO) model. The results of fitting to the experimental data show that the MPnO model has low relative errors in the whole range of adsorption time.     

1-(1-Alkylsulfonic)-3-methylimidazolium chloride as a reusable Brønsted acid catalyst for the regioselective azidolysis of epoxides under solvent-free conditions

In this study, 1-(1-alkylsulfonic)-3-methylimidazolium chloride as a new, green, and reusable Brønsted acid catalyst was prepared. In this protocol, we used for the regioselective ring-opening reactions of various epoxiodes with sodium azide to afford the corresponding β-azido alcohols in excellent yields and short reaction time under mild and neutral reaction conditions. This method offers several advantages including excellent regioselectivity, clean reactions, simple work-up procedure, a recyclable catalyst, and use of an eco-friendly catalyst.     

A synthesis of diethyl alkylsulfanylmethylmalonates catalyzed by KOH in an ionic liquid

Abstract  

1-Ethyl-3-methylimidazolium bromide was used as a green recyclable alternative to volatile organic solvents for KOH catalyzed three-component synthesis of diethyl alkylsulfanylmethylmalonates from aldehydes, diethyl malonate, and alkylthiols.