title: An asymmetric assembly of spirooxindole dihydropyranones through a direct enantioselective organocatalytic vinylogous aldol-cyclization cascade reaction of 3-alkylidene oxindoles with isatins.
abstract: A highly enantioselective organocatalytic vinylogous aldol-cyclization cascade reaction of 3-alkylidene oxindoles to isatins has been achieved by using bifunctional organocatalysts. The unexpected intramolecular lactonization which follows the initial aldol reaction, leading to the cleavage of the oxindole ring and generation of enantioenriched spirooxindole dihydropyranones in good to excellent yields with high enantioselectivities.
authors.affiliation: Department of Chemistry, Chung Yuan Christian University, Taoyuan City, Taiwan 32023. jlhan@cycu.edu.tw.
authors.forename: Jeng-Liang
authors.initials: JL
authors.lastname: Han
authors.affiliation: Department of Chemistry, Chung Yuan Christian University, Taoyuan City, Taiwan 32023. jlhan@cycu.edu.tw.
authors.forename: Chia-Hao
authors.initials: CH
authors.lastname: Chang
mesh_terms: D000447:Aldehydes / Q000737:chemistry*; D002384:Catalysis; D003500:Cyclization; D007211:Indoles / Q000737:chemistry*; D011714:Pyrans / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000447:Aldehydes; D007211:Indoles; D011714:Pyrans; C116609:3-hydroxybutanal