ADVANCES IN THE SYNTHESIS OF QUINAZOLINONES VIA THE CONDENSATION OF 2-AMINOBENZAMIDE AND ALDEHYDES: A JOURNEY FROM CLASSICAL TO SUSTAINABLE PROTOCOLS

The condensation of 2-Aminobenzamide with aldehydes represents a cornerstone strategy for constructing Quinazolin-4(3H)-one and 2,3-Dihydroquinazolin-4(1H)-one scaffolds, privileged structures in medicinal chemistry due to their diverse pharmacological profiles. This review chronicles the significant evolution of this transformation, tracing its progression from early classical methods reliant on strong acids and high temperatures to contemporary green and sustainable synthetic paradigms. We highlight key advancements including the adoption of Lewis acid catalysts, microwave irradiation, and innovative oxidative systems. A particular focus is placed on modern breakthroughs such as metal-free organocatalysis, solvent-free mechanochemical approaches, and the application of nanocatalysts and reusable heterogeneous systems. These developments have collectively enhanced the environmental compatibility, efficiency, and stereoselectivity of this reaction, solidifying its status as a versatile and indispensable tool in synthetic and medicinal chemistry.