title: Chiral spirooxindole-butenolide synthesis through asymmetric N-heterocyclic carbene-catalyzed formal (3 + 2) annulation of 3-bromoenals and isatins.
abstract: By using an N-heterocyclic carbene catalyst bearing a hydroxyl moiety, the asymmetric formal (3 + 2) cyclization of aryl 3-bromoenals and isatins was achieved to produce a series of chiral spirooxindole-butenolides including an alkenyl-substituted compound, which underwent benzannulations with benzynes to form intriguing spirocyclic scaffolds.
authors.affiliation: Department of Chemistry, Zhejiang University , 20 Yugu Road, Hangzhou 310027, China.
authors.forename: Chenguang
authors.initials: C
authors.lastname: Zheng
authors.forename: Weijun
authors.initials: W
authors.lastname: Yao
authors.forename: Yucheng
authors.initials: Y
authors.lastname: Zhang
authors.forename: Cheng
authors.initials: C
authors.lastname: Ma