A highly efficient catalytic asymmetric Diels-Alderreaction between 3-vinylindoles and methyleneindolinones has been achieved using chiral N,N'-dioxide-Ni(II) complexes as the catalysts. A wide variety of substrates were readily tolerated, generating exclusively the corresponding exo-carbazolespirooxindole derivatives in excellent yields with high enantiomeric excesses (up to 98% yield, >99 : 1 d
An efficient Diels–Alderreaction of 3-hydroxy-2-pyrone with a wide range of methyleneindolinones has been developed by employing 4-dimethylaminopyridine as a catalyst under mild reaction conditions. This process provides a promising method for the construction of structurally diverse spirocyclic oxindoles containing bicyclic lactone motif with moderate diastereoselectivities and good to excellent