Cascade arylalkylation of activated alkenes: synthesis of chloro- and cyano-containing oxindoles.

The general method for the oxidative cyclization of arylacrylamides with dichloromethane or acetonitrile has been developed. The reactions described provide novel access to chloro- and cyano-containing oxindoles in good to moderate yields that allow the direct formation of a C-C bond and the construction of an oxindole ring in one reaction. The use of a cheap and easily prepared Mn(OAc)3 represents an added advantage of this method.