Access to highly enantioselective and diastereoselective spirooxindole dihydrofuran fused pyrazolones from MBH-carbonates and pyrazole 4,5-diones.

A highly regioselective [3+2] annulation of Morita-Baylis-Hillman (MBH) carbonates of isatin with aurone/thioaurone is developed. Spiroheterocycles such as spirooxindole cyclopentadiene and spirooxindole fused hydroxy cyclopentene derivatives are constructed in one...

A DMAP catalyzed highly diastereoselective [3 + 2] cycloaddition of pyrazolone derived Morita-Baylis-Hillman (MBH) carbonate and 3-methyleneoxindole has been developed. A variety of structurally diverse and complex spiropyrazolone fused oxindoles bearing three contiguous chiral centers have been synthesized in very high yields (up to 98%) with excellent diastereoselectivity (up to 99:1). Moreover, the synthetic potential of this protocol has been demonstrated by performing Suzuki coupling reaction.