Structure-dependent tautomerization induced catalyst-free autocatalyzed N-alkylation of heteroaryl amines with alcohols

Catalyst-free autocatalyzed dehydrative N-alkylation reactions of 2-aminobenzothiazoles, 2-aminopyrimidines, and 2-aminopyrazine with primary and secondary alcohols have been achieved for efficient, practical, and green synthesis of the versatile heteroaryl amine derivatives. These reactions were interestingly induced by structure-dependent tautomeric equilibria of the heteroaryl amines via MPV–O transfer hydrogenation of the imino tautomers by alcohols to give aldehydes as the key initiating step.