In this work a novel heterojunction catalyst have been synthesized and employed as a highly efficient catalyst for one-pot synthesis of substituted imidazoles. Analytical methods including Fourier transform infrared (FT-IR), diffuse reflectance spectroscopy (DRS), X-ray diffraction (XRD), Energy- dispersive X-ray spectroscopy (EDX), Scanning electron microscopy (SEM) and Vibrating Sample Magnom...

Studies with C-2-labelled glycine and alanine in model systems containing 2,3-butanedione, glyceraldehyde or glyoxal have indicated that imidazoles and oxazoles can be formed from a-dicarbonyl compounds through Strecker reaction and subsequent formation of a-amino carbonyl reactive intermediates. These intermediates can react with any aldehyde in the reaction mixture to form an imine which in t...

Substituted imidazoles and oxazoles were respectively hydrogenated into the corresponding chiral imidazolines and oxazolines (up to 99% ee). The highly enantioselective hydrogenation was achieved by using the chiral ruthenium catalyst, which is generated from Ru(η(3)-methallyl)(2)(cod) and a trans-chelating chiral bisphosphine ligand, PhTRAP. This is the first successful catalytic asymmetric re...

Mesoionic 4-trifluoroacetyl-1,3-oxazolium-5-olates (1), obtained from the reaction of N-acyl-N-alkylglycines (2) with trifluoroacetic anhydride, react with amidines to give 5-trifluoroacetylimidazoles (3) in moderate yield. The novel ring transformations of 1 into 3 occur via an initial attack of amidines on the C-2 position of the ring.

The kinetics of the reactions of some imidazoles, benzimidazoles and benzotriazoles with benzhydrylium ions (diarylcarbenium ions) have been studied photometrically in DMSO, acetonitrile, and aqueous solution at 20 degrees C. The resulting second-order rate constants have been used to determine the nucleophile-specific parameters N and s of these azoles according to the linear-free-energy relat...

The trisubstituted enolate- and C-C bond-forming capacities of engineered carboxymethylproline synthases CMPSs are coupled with the malonyl-CoA synthetase MatB to enable stereoselective preparation of 5- and 6-membered N-heterocycles functionalised with alkyl-substituted carboxymethyl side chains, starting from achiral alkyl-substituted malonic acids and L-amino acid semialdehydes. The results ...