DMAP-promoted in situ activation of bromoacetic acid as a 2-carbon synthon for facile synthesis of pyridines and fused pyridin-2-ones

Abstract A general and simple synthesis of 2,4,6-trisubstituted pyridines and fused pyridine-2-ones from bromoacetic acid is developed via a DMAP-promoted in situ activation strategy. In this protocol, readily accessible bromoacetic acid has been effectively employed as a 2C synthon to undergo formal [2+4] cycloadditions with diverse acyclic and cyclic 1-azadienes. Low costs of the reagents and materials, mild reaction conditions and broad functional-group tolerance make this protocol applicable for practical and scalable synthesis.