The catalytic system formed in situ from the reaction of Ru–H complex [(C6H6)(PCy3)(CO)RuH]+BF4- (1) with 2,3,4,5-tetrachloro-1,2-benzoquinone (L1) was found to mediate a highly effective catalytic system for promoting the deaminative coupling reaction of 2-hydroxyarylketones with simple amines to form 3-substituted flavanone products. Both aliphatic and benzylic amines were found to be suitable substrate to react with 2’-hydroxyaryl ketones to form the flavanone products. The analogous deaminative coupling reaction of 2-aminobenzamides with branched amines directly led to the formation of quinazolinone products. The Hammett plot obtained from the reaction of para-substituted 2’-hydroxy-5’-X-acetophenones (X = OMe, Me, H, F, Cl) with n-hexylamine showed a strong promotional effect by the ketone substrate with electron-releasing groups (ρ = -0.9 ± 0.2). The most significant carbon isotope effect was observed on the α-carbon next to the phenolic oxygen C(3) = 1.017(5). The reaction of a preformed ketimine with n-hexylamine under the standard conditions in presence of water cleanly formed the flavanone product. Both substrate scope and mechanism of the catalytic deaminative coupling reaction will be presented.

Scope and mechanism of ruthenium catalyzed deaminative coupling of 2-hydroxyarylketones and 2-aminobenzamides with amines for the synthesis of flavanone and quinazolinone derivatives

Fall 2022 abstracts, posters, and presentations will launch in mid-September.

ACS Fall 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.