title: Highly asymmetric bromocyclization of tryptophol: unexpected accelerating effect of DABCO-derived bromine complex.
abstract: Highly asymmetric bromocyclization of tryptophol by using chiral anionic phase-transfer catalyst and DABCO-derived brominating reagent is described. Optimization of the reaction conditions revealed that the reaction rate was accelerated together with improvement of enantioselectivity by addition of catalytic DABCO-derived brominating reagent. From tryptophol, 3-bromofuroindoline could be directly obtained in excellent enantioselectivities by employing this novel methodology.
authors.affiliation: State Key Laboratory of Natural Medicines, Center of Drug Discovery, China Pharmaceutical University , 24 Tongjiaxiang, Nanjing 210009, China.
authors.forename: Huan
authors.initials: H
authors.lastname: Liu
authors.forename: Guangde
authors.initials: G
authors.lastname: Jiang
authors.forename: Xixian
authors.initials: X
authors.lastname: Pan
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Wan
authors.forename: Yisheng
authors.initials: Y
authors.lastname: Lai
authors.forename: Dawei
authors.initials: D
authors.lastname: Ma
authors.forename: Weiqing
authors.initials: W
authors.lastname: Xie
mesh_terms: D002384:Catalysis; D002625:Chemistry, Organic / Q000379:methods; D003500:Cyclization; D006842:Hydrocarbons, Brominated / Q000138:chemical synthesis* / Q000737:chemistry; D006847:Hydrocarbons, Iodinated; D007211:Indoles / Q000737:chemistry*; D015394:Molecular Structure; D010879:Piperazines / Q000737:chemistry*; D013237:Stereoisomerism; D000438:Alcohols
chemical_list: D006842:Hydrocarbons, Brominated; D006847:Hydrocarbons, Iodinated; D007211:Indoles; D010879:Piperazines; C000588838:3-bromofuroindoline; C005949:tryptophol; D000438:Alcohols; C007306:triethylenediamine