An organocatalytic asymmetric trifluoromethylthiolation reaction via in situ generation of active electrophilic trifluoromethylthio species involving trichloroisocyanuric acid and AgSCF3 as a practical and easily handled electrophilic SCF3 source for CSP(3)-SCF3 bond formation was developed. Reactions with this one-pot version strategy occurred in good yields and excellent stereoselectivities to access enantiopure oxindoles bearing a SCF3-substituted quaternary chiral center. The straightforward process described here makes use of simple starting materials and proceeds under mild conditions, which will be useful in medicinal chemistry and diversity-oriented syntheses.

An organocatalytic asymmetric vinylogous Michael addition of dicyanoolefins to vinylogous imine intermediates generated in situ from arenesulfonylalkylindoles has been developed. This protocol provides an easy and convenient approach to C-3 alkyl-substituted indole derivatives with high yields (up to 93%), diastereomeric ratios (up to 99:1 dr) and enantioselectivities (up to 99% ee). The resulting adducts can be also readily converted to pyrazolo derivatives or a-alkylation products of ketones without any decrease of the diastereoselectivities and enantioselectivities.

Enantioselective Michael addition of oxazolones to in situ generated vinylogous imine intermediates is reported. A series of optically active 3-alkylindole derivatives with adjacent quaternary and tertiary stereocenters was obtained. The[a] Chemical Synthesis and Pollution 456 resulting adducts can readily be converted into syn-configured α,β-disubstituted tryptophan derivatives without compromising the stereoselectivities.

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Organocatalytic Asymmetric Michael Addition of Oxazolones to Arylsulfonyl Indoles: Facile Access to syn-Configured α,β-Disubstituted Tryptophan Derivatives. -For the first time the highly stereoselective title Michael addition reaction is presented. The resulting adducts [e.g.(III)] with quaternary and tertiary stereocenters can be readily converted into syn-configured α,β-disubstituted tryptophan derivatives [cf. (IV)] without a decrease in dia-and enantioselectivities. -(CAI, C.-W.; ZHU, X.-L.; WU, S.; ZUO, Z.-L.; YU, L.-L.; QIN, D.-B.; LIU, Q.-Z.; JING*, L.-H.; Eur. J. Org. Chem. 2013, 3, 456-459, http://dx.