Reaction of N-substituted cyclic amines with 2,4-dichloroquinazoline, 2,4-dichloropyrimidine, and its 5-methyl derivative

Abstract

The reaction of N-substituted cyclic amines with 2,4-dichloroquinazoline 2 and 2,4-dichloro-5-methyl-pyrimidine 3b afforded 2-amino-4-chloroquinazolines and 2-amino-4-chloro-5-methylpyrimidines, respectively. However, the reaction of these amines with 2,4-dichloropyrimidine 3a afforded not only 2-amino-4-chloropyrimidines but also the isomeric 4-amino-2-chloropyrimidines. The regio-selectivity of these reactions was considered to be determined by the steric nature of the substrates 2, 3a, and 3b.