Catalyst-Free One-Pot Multi-Component Synthesis of 2-Substituted Quinazolin-4-carboxamides from 2-Aminophenyl-2-oxoacetamides, Aldehydes, and Ammonium Acetate

Herein, we report a simple and straightforward catalyst-free one-pot multi-component synthesis of quinazolin-4-carboxamides using 2-(2-aminophenyl)-N,N-dialkyl-2-oxoacetamide, aldehydes and ammonium acetate. As compared to the conventional approached for quinazolin-4-carboxamides synthesis, this transformation demonstrates very good reactivity by tolerating a large number of functional groups, and proceeds with good to moderate yields under mild conditions. Notably, the synthesized 6-bromoquinazolin-4-carboxamide was subjected to Suzuki-Miyaura cross-coupling and Buchwald-Hartwig C−N bond forming reactions providing a straightforward method to obtain structurally diverse and valuable quinazoline scaffolds. Furthermore, the reaction could be easily scaled up to gram scale.