A method for the synthesis of pyridines from aldehydes, alkynes and NH4OAc involving Rh-catalyzed hydroacylation and N-annulation

A new method for regiocontrolled pyridine synthesis has been developed involving sequential Rh(I)-catalyzed chelation-assisted hydroacylation of alkynes with aldehydes followed by Rh(III)-promoted N-annulation of the resulting α,β-enones with another alkyne and NH(3).