Palladium-catalyzed alkenyl C-H bond sulfonylation reaction using organosulfonyl chlorides

A Pd-catalyzed alkenyl C-H bond direct sulfonylation of vinyl pyridine and enamides was developed. Various arylsulfonyl chlorides were tested in this reaction and the desired products were obtained in good yields. Moreover, the alkyl sulfonyl chloride could also be used though the yield was lower. A possible Pd(II)/Pd(IV) catalytic pathway involved in this coupling reaction was proposed.