An alternative method for the direct arylvinylation of (quinolin-8-yl)methanone with substituted N′-benzylidene-4-methylbenzenesulfonohydrazide is described. The desired 3-aryl-1-(quinolin-8-yl)prop-2-en-1-one products are obtained in high yields through the catalytic reaction of (quinolin-8-yl)methanone and N′-arylidene-4-methylbenzenesulfonohydrazide (2 equiv) with [Rh(PPh3)3Cl] (10 mol%), Ag2O (0.5 equiv), and Cs2CO3 (2 equiv) at 130 °C for 48 hours. Two plausible mechanisms involving C–H activation and migratory insertion of the carbene into the rhodium–carbon bond were proposed to explain the formation of the product.
Key words
quinolinone - rhodium complex - hydrazones - C–C coupling - double-bond formation