Imidazo[1,2-a]pyridine derivatives synthesis from lignin β-O-4 segments via a one-pot multicomponent reaction.

The catalytic conversion of lignin into N-containing chemicals is of great significance for the realization of value-added biorefinery concept. In this article, a one-pot strategy was designed for the transformation of lignin β-O-4 model compounds to imidazo[1,2-a]pyridines in yields up to 95% using 2-aminopyridine as a nitrogen source. This transformation involves highly coupled cleavage of C-O bonds, spC-H bond oxidative activation, and intramolecular dehydrative coupling reaction to construction of N-heterobicyclic ring.