Rational design and expeditious synthesis of aromatic cyanodienone derivatives assisted by cyanide-halide exchange

Abstract

1-n-Butyl-3-methylimidazolium cyanide ([bmim]CN), in the presence of [bmim]Br has been prepared and used for the first time as the medium as well as reagent for the synthesis of aromatic cyanodienones from the corresponding triarylpyrylium perchlorates by cyanide-halide exchange. The [bmim]CN having a reactive anion, is an accelerated reaction technique without external solvent and renders the whole synthesis into a truly eco-friendly protocol. The products can be isolated without aqueous work-up in high purity and excellent yield.