The Chemistry of 2'-Amino Analogues of 2'-Hydroxychalcone and Its Derivatives

Article abstract of DOI:10.1021/jo00293a017

The cyclization of 2'-aminochalcone (2a) and its side-chain additives has been studied for the development of syntheses of 2-aryl-4-quinolones. 2a and its 2'-acetamido 2b and 2'-benzenesulfonamido 2c derivatives underwent acid- or base-catalyzed cyclization to 1,2,3,4-tetrahydro-4-quinolones.The α,β-dibromides of 2b and 2c cyclized to cis-3-bromo-4-quinolones as did the corresponding α-bromochalcones and the α-bromo-β-methoxy additive of 2c. 2'-Acetamido-α-bromochalcone was cyclized by acid to 1,4-dihydro-2-phenyl-4-quinolone. 2'-Aminochalcone formed a stableepoxide which, with acid, gave cis-3-hydroxy-1,2,3,4-tetrahydro-3-phenyl-4-quinolone. 2'-Aminochalcones 2a-c and their additives, such as dibromide and epoxide, are useful, readily available precursors of various 2-aryl-4-quinolones.