Microwave Assisted Synthesis of 5-Aryl-Thiophene-2-Carboxylates

Abstract

A simple and rapid method for the synthesis of 5-Aryl-thiophene-2-carboxylates 3 has been developed by the condensation of ß-chlorovinyl aldehydes 1 with mercaptoacetic acid esters 2 under microwave irradiation conditions. Abstract 1 2 3 SCHEME-1

A simple synthesis of functionalized 2-amino-3-cyano-4-chromones by application of the N-hydroxybenzotriazole methodology

“…1, 18 3-Cyanochromones have been synthesized in a mild and facile method from oximes derived from 3-formyl chromones using dimethyl formamide/ thionyl chloride complex. 19 As for aminochromones, useful for the prevention of allergic and asthmatic reactions in mammals, as indicated by tests in rats, they have been synthesized either by rearrangement of isoxazoles 20 or from chlorinated salicylic acids and malononitrile in aqueous NaOH or NaH. 21 During the last few years we have been involved in the one-step synthesis of heterocycles 22a, 22b employing N-hydroxybenzotriazole esters of α-amino or α-hydroxy acids as acylating agents of active methylene compounds to produce a wide variety of γ-amino 22c or γ-hydroxy butenoates, 22d which can be converted to five-membered heterocycles with biological interest.…”