title: Substrate-controlled switchable asymmetric annulations to access polyheterocyclic skeletons.
abstract: An unexpected domino process from Morita-Baylis-Hillman carbonates of isatins and acrylate and α-cyano-α,β-unsaturated ketones to deliver highly enantioenriched tetrahydrofuro[2',3':4,5]pyrano[2,3-b]indoles catalysed by cinchona-derived tertiary amines, involving α-regioselective cyclopropanation, ring-opening, and ring-closure cascade reactions, was disclosed. In contrast, spirooxindoles incorporating a cyclopentene motif were produced through [3+2] annulations by employing Morita-Baylis-Hillman carbonates from isatins and acrylonitrile under similar catalytic conditions. Density functional theory calculations were conducted to elucidate the novel domino process and the switchable annulation reactions.
authors.affiliation: Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education, West China School of Pharmacy, Sichuan University, Chengdu 610041, China. ycchen@scu.edu.cn.
authors.forename: Kai-Kai
authors.initials: KK
authors.lastname: Wang
authors.forename: Pan
authors.initials: P
authors.lastname: Wang
authors.forename: Qin
authors.initials: Q
authors.lastname: Ouyang
authors.forename: Wei
authors.initials: W
authors.lastname: Du
authors.forename: Ying-Chun
authors.initials: YC
authors.lastname: Chen