Introduction of alkyl groups at the α-positions of pyrrolidines and piperidines: Synthesis of (±)-coniine

Article abstract of DOI:10.3987/COM-88-4567

The conversion of lactams to α-alkylated cyclic amines is described. Reactions of α-ethoxyurethanes with trimethylsilyl cyanide in the presence of Lewis acid afford the corresponding α-cyanourethanes, which, via carbanion, are alkylated to α-alkyl-α-cyanourethanes in moderate to high yields. Syntheses of (±)-coniine and trans-quinolizidine are carried out as model experiments for dealkoxycarbonylation and decyanation of 2-alkyl-1-alkoxycarbonyl-2-cyanopiperidines.