Palladium-Catalyzed Carbo-Heterofunctionalization of Alkenes for the Synthesis of Oxindoles and Spirooxindoles
摘要:
A palladium-catalyzed oxidative carbo-heterofunctionalization of aniline derivatives involving concomitant direct C H functionalization and C X bond formation was developed By simply changing the reaction conditions (solvent and catalyst), either 3,3'-disubstituted oxindole or spirooxindole was accessible from the same starting material.
Cyclisative carbo-iodination of N-alkyl-N-arylacrylamide derivatives (3) in the presence of PhI(OAc)(2)/I-2 afforded functionalized 3-(iodomethyl)-3-substituted-indolin-2-ones (4) in good to excellent yields. With a suitably functionalized linear amide, spirooxindole 8 was prepared in a one-pot fashion via a sequence of iodo-arylation followed by an in situ base-promoted intramolecular S(N)2 reaction.