title: Phosphine-Initiated General-Base-Catalyzed Quinolone Synthesis.
abstract: Phosphinocatalysis provides a new approach toward 3-substituted-4-quinolones. A simple procedure, which uses Ph3P as an inexpensive catalyst andS-phenyl 2-(N-tosylamido)benzothioates and activated alkynes as starting materials, provides direct access to several 3-aroyl-4-quinolones and methyl 4-quinolone-3-carboxylate esters. The reaction presumably occurs through general base catalysis, with the initial addition of Ph3P to the activated alkyne generating the phosphonium enoate zwitterion, which acts as the strong base that initiates the reaction.
authors.affiliation: Department of Chemistry and Biochemistry, University of California, Los Angeles, 607 Charles E. Young Dr. East, Los Angeles, California 90095-1569 (USA).
authors.forename: San
authors.initials: S
authors.lastname: Khong
authors.affiliation: Department of Chemistry and Biochemistry, University of California, Los Angeles, 607 Charles E. Young Dr. East, Los Angeles, California 90095-1569 (USA).
authors.forename: Ohyun
authors.initials: O
authors.lastname: Kwon
keywords: 4-quinolone; acyl substitution; michael addition; phosphine catalysis; quinoline