Pinner Reaction (Amidine and Ortho Ester Synthesis)

A. Pinner, F. Klein, Ber. 10, 1889 (1877); 11, 4, 1475 (1878); 16, 352, 1643 (1883).

Formation of imino esters (alkyl imidates) by addition of dry hydrogen chloride to a mixture of a nitrile and an alcohol. Treatment of alkyl imidates with ammonia or primary or secondary amines affords amidines, while treatment with alcohols yields ortho-esters:

Reviews: R. Roger, D. Neilson, Chem. Rev. 61, 179 (1961); E. N. Zil'berman, Russ. Chem. Rev. 31, 615 (1962); P. L. Compagnon, M. Moeque, Ann. Chim. (Paris) 5, 23 (1970); B. Decroix et al., J. Chem. Res. 1978, 134.