Diastereoselective C-H carbonylative annulation of aliphatic amines: a rapid route to functionalized γ-lactams.

A palladium(ii)-catalysed C(sp)-H carbonylation of free(NH) secondary aliphatic amines to 2-pyrrolidinones is described. A correlation between the nature of the carboxylate ligand and the diastereoselectivity and yield of the process was observed. As such, under these optimal conditions a range of aliphatic amines were converted to the corresponding trans-4,5-disubstituted 2-pyrrolidines with good d.r. and yield.