Heterocycles in organic synthesis. Part 6. Nucleophilic displacements of primary amino-groups via 2,4,6-triphenylpyridinium salts

Abstract

Benzylamine and 2-, 3-, and 4-pyridylmethylamine are readily converted into the corresponding 1-substituted 2,4,6-triphenylpyridinium cations, from which 2,4,6-triphenylpyridine is displaced in high yield by a variety of nucleophiles. This synthetic method avoids the use of unstable and obnoxious pyridylmethyl halides and shows steric selectivity of significance in the conversion of secondary into tertiary amines by alkylation.