Ultrasonic Assisted Synthesis of Chromenes Catalyzed by Sodium Carbonate in Aqueous Media

Abstract

A simple, efficient, and environmentally benign procedure for the synthesis of 2-amino-4H-chromene ring has been achieved by the three-component reaction of an aromatic aldehyde, malononitrile and diverse enolizable C-H activated compound under ultrasound irradiation using sodium carbonate as a catalyst in aqueous media. Sodium carbonate as a natural salt, being available as an inexpensive catalyst combined with ultrasound method promoted this protocol in comparison to other methods and catalysts.

Multifarious Stage Synthesis of Uniquely Substituted Chromeno Derivatives of Carboxy and Amino Pyrimidine

“…Active hydrogen compounds like diethyl malonate, Meldrum's acid, ethyl acetoacetate, malonic acid, cyanoacetic acid, malononitrile etc. [22][23][24] .Michael addition is suitable for the superior class of multiple additions. It is a convenient method for C-C bond formation.…”