Substrate- and reagent-dependent selective annulation of amidines and 2-tert-amino benzaldehydes

Abstract

Herein, we present an efficient and substrate/reagent-dependent annulation of amidines with 2-tert-amino benzaldehydes. When N-alkyl benzimidamides are employed, amidines undergo self-annulation to generate a hydrotriazine skeleton. In contrast, N-aryl benzimidamides yield quinazolines/hydroquinazolines under similar conditions. Additionally, the coupling of 2-tert-amino benzaldehydes with amidines under basic conditions yields 1,3,5-triazine derivatives.