A new and convenient one-pot solid supported synthesis of 2,4,6-triarylpyridines

A new, convenient, efficient and cost-effective one-pot solid supported synthesis of 2,4,6-triarylpyridines from benzylideneacetophenones and urea, thiourea or their derivatives, using Bi(III) nitrate-Al2O3 is described. The reaction seems to proceed via β-oxygenation of Bi(III)-enolized benzylideneacetophenone followed by Michael addition, heteroannulation with simultaneous retro aldol disproportionation and subsequent catalytic oxidation and dehydration.