Synthesis of polycyclic lactams via intramolecular dipolar cycloadditions of stabilized azomethine ylides

Article abstract of DOI:10.1016/S0040-4039(01)93412-4

A stereoselective two step sequence for the construction of fused pyrrolidone ring systems has been developed which features the intramolecular [3 + 2] dipolar cycloaddition of unsaturated azomethine ylides. The ylides are produced upon reaction of aminomethylphosphonates with α,ω-olefinic aldehydes, followed by oxidative removal of the phosphonate ester group using a newly developed method.