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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 resulting adducts can readily be converted into syn-configured α,β-disubstituted tryptophan derivatives without compromising the stereoselectivities. [ABSTRACT FROM AUTHOR]

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 α-alkylation products of ketones without any decrease of the diastereoselectivities and enantioselectivities. [ABSTRACT FROM AUTHOR]

In the title compound, C12H8N2O4Se, the Se atom is situated on a twofold rotational axis, so the asymmetric unit contains one half-mol-ecule. In the mol-ecule, the C-Se-C angle is 99.48 (13)°, the two benzene rings are inclined to each other at an angle of 63.8 (1)° and the nitro group is twisted by 15.9 (1)° from the attached benzene ring. In the crystal, mol-ecules are held together through weak C-H⋯O inter-actions, forming a three-dimensional network.