Enantioselective Michael Addition of 1,3-Diketones to Arenesulfonylalkylindoles: A Flexible Gateway to Optically Active 3-sec-Alkyl-Substituted Indoles Containing a Pyrazole Skeleton
4-positions, without decrease of the enantioselectivity. EnantioselectiveMichaeladdition of 1,3-diketones to alkylideneindolenines generated in situfrom arenesulfonylalkylindoles is described, and a series of optically active C3-alkyl-substituted indole derivatives has been obtained. The resulting adducts can be readily converted into 3-sec-alkyl-substituted indoles containing a pyrazole skeleton, with
Solvent-Free Non-Covalent Organocatalysis: Enantioselective Addition of Nitroalkanes to Alkylideneindolenines as a Flexible Gateway to Optically Active Tryptamine Derivatives
A catalytic asymmetric addition of nitroalkanes to alkylideneindolenines, generated in situ from arylsulfonylindoles, is presented. Despite the weakness of the non‐covalent H‐bond interactions between catalyst and substrates, the performance of the bifunctional organocatalyst used was found to be essentially unaffected by the polarity of the reaction medium. Nitroalkanes, mostly used in nearly stoichiometric
Catalytic asymmetric coupling of vinylogous species <i>via</i> deconjugated butenolide addition to vinylogous imines <i>in situ</i> generated from arylsulfonyl indoles
An efficient catalytic asymmetric coupling of vinylogous species is developed via deconjugated butenolide addition to vinylogousimines in situgeneratedfromarylsulfonylindoles. With quinine-derived bifunctional squaramide as the catalyst, a series of structurally diverse enantioenriched sec-alkyl-3-substituted indoles containing valuable γ,γ-disubstituted butenolide moieties and adjacent quaternary-tertiary
An efficient organocatalyzed enantioselective hydrophosphinylation of indole-derived vinylogous imines generated in situ from sulfonyl indoles has been developed. Using quinine-derived bifunctional thiourea as the catalyst, a wide range of structurally diverse chiral 3-(1-diphenylphosphoryl-arylmethyl)indoles were obtained with good to excellent results (up to 99% yield and 99% ee). This method represents
A highly enantioselective thiolation of sulfonyl indoles to access 3-sec-sulfur-substituted indoles in water
作者:Ping Chen、Sheng-mei Lu、Wengang Guo、Yan Liu、Can Li
DOI:10.1039/c5cc07721d
日期:——
Highlyenantioselective organocatalytic Michaeladdition of thiol to vinylogousimineintermediatesgenerated in situfrom sulfonylindoles in aqueous medium is presented.