Investigation of the reactivity of (1H-benzo[d]imidazol-2-yl)acetonitrile and (benzo[d]thiazol-2-yl)acetonitrile as precursors for novel bis(benzo[4,5]imidazo[1,2-a]pyridines) and bis(benzo[4,5]thiazolo[3,2-a]pyridines)

Abstract

A synthesis of novel bis(benzo[4,5]imidazo[1,2-a]pyridines) via the reaction of the appropriate bis(aldehyde) with 2-(1H-benzo[d]imidazol-2-yl)acetonitrile and malononitrile in ethanol at reflux in the presence of piperidine was reported. On the other hand, attempted synthesis of bis(benzo[4,5]thiazolo[3,2-a]pyridines) by a three-component reaction of the appropriate bis-aldehyde with malononitrile and (benzo[d]thiazol-2-yl)acetonitrile under similar reaction conditions was unsuccessful. The reactions gave instead the corresponding novel bis(benzo[d]thiazol-2-yl)acrylonitriles.

Graphical Abstract

Keywords:

• Bis(benzo[4,5]imidazo[1,2-a]pyridines)
• bis(benzo[4,5]thiazolo[3,2-a]pyridines)
• bis-heterocycles
• multicomponent reactions