A simple, one-flask transformation of ketones to N-methyl lactams

Article abstract of DOI:10.1016/S0040-4039(00)74345-0

A one-flask conversion of cyclic ketones to N-methyl lactams is described. Reaction of the ketone with triethylorthoformate generates an acetal which is reacted in situ with N-(((p-nitrobenzene)sulfonyl)oxy methylamine 2a(CH₃NH-OSO₂C₆H₄NO₂). Dealkylation of the resulting O-ethyl imidate with sodium iodide gives the lactam. A variety of lactams, including macrocyclic lactams, are produced simply and in good yields.