ABSTRACT A new and efficient B(C6F5)3 catalyzed domino strategy has been developed for the synthesis of 2-substituted quinazolinones. The reaction utilizes 2-aminobenzamide and aldehydes for a one-pot protocol. A wide range of substrate scope, functional group tolerance, and operational simplicity with excellent yield are synthetically useful features. GRAPHICAL ABSTRACT ARTICLE HISTORY Received 5 August 2019 KEYWORDS Aldehyde; 2-aminobenzamide; quinazolinone; tris(pentafluorophenyl) borane

The behavior of 2-ethoxy-4-chloroquinazoline 2 towards various nitrogen nucleophiles, namely: thiosemicarbazide, sodium azide, glucosamine, ethanol, and hydrazine hydrate has been discussed. Also, the behavior of 4-(2-ethoxyquinazolin-4-yl)thiosemicarba- zide towards one-carbon, for example, ethyl chloroformate, and two-carbon donors, for example, ethyl chloroacetate and diethyl oxalate has been investigated. On the other hand, new 5-ethoxy-2-substituted[1,2,4]-triazolo-[1,5-c]quinazoline derivatives have been obtained by ring closure accompanied with Dimroth rearrangement through the interaction of compound 2 with hydrazides of acetic, benzoic, crotonic, cinnamic, 2-furoic, and phthalimidoacetic acids. Structures of the novel products were confirmed by elemental, IR, MS, and 1H-NMR spectral analyses.