Metal-free [3 + 2 + 1] annulation of allylic alcohols, ketones, and ammonium acetate: radical-involving synthesis of 2,3-diarylpyridine derivatives.

A three-component [3 + 2 + 1] annulation strategy for the synthesis of biologically and pharmaceutically active 2,3-diarylpyridine derivatives by using a series of allylic alcohols, ketones, and ammonium acetate as substrates has been developed. The method proceeds efficiently under metal-free conditions, and the desired heterocycles could be obtained in a site-specific selectivity manner with good functional group tolerance.