Palladium-catalyzed coupling of tetraphenylbismuth(V) derivatives with methyl acrylate
摘要:
Tetraphenylbismuth(V) derivatives of the general formula Ph4BiX [X = OSO2C6H4Me-4, OC6H2(NO2)(3)-2,4,6, OC6H2(NO2-4)(Br-2-2,6), OSO2C6H3(OH)(COOH)] react with methyl acrylate in the presence of palladium dichloride (1:3:0.04 molar ratio) in acetonitrile at 20 degrees C to form the cross-coupling I products, methyl cinnamate (0.17-0.54 mol mol(-1) starting bismuth compound) and methylhydrocinnamate (0.10-0.73 mol mol(-1)), diphenyl (0.06-0.80 mol mol(-1)), and benzene (0.02-0.36 mol mol(-1)). The highest C-phenylating activity is shown by Ph4BiOSO2C6H4Me-4. The mechanisms with the palladium-catalyzed cross-coupling reactions are suggested.