title: Iron-catalyzed imidative kinetic resolution of racemic sulfoxides.
abstract: Kinetic resolution of racemic sulfoxides requires either custom substrates or shows moderate enantioselectivity, leading to achiral coproducts (such as sulfones) as an intrinsic part of the process. A new strategy is demonstrated that allows the resolution of racemic sulfoxides through catalytic asymmetric nitrene-transfer reactions. This approach gives rise to both optically active sulfoxides and highly enantioenriched sulfoximines. By using a chiral iron catalyst and a readily available iodinane reagent, high selectivity factors have been achieved under very practical reaction conditions. With respect to the substrate scope, it is noteworthy that this unprecedented imidative kinetic resolution of racemic sulfoxides provides access to both aryl-alkyl and dialkyl sulfoximines in highly enantioenriched forms.
authors.affiliation: Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52056 Aachen (Germany), Fax: (+49) 241-8092391 http://bolm.oc.rwth-aachen.de; Current address: School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275 (P.R. China).
authors.forename: Jun
authors.initials: J
authors.lastname: Wang
authors.forename: Marcus
authors.initials: M
authors.lastname: Frings
authors.forename: Carsten
authors.initials: C
authors.lastname: Bolm
keywords: iron catalysis; kinetic resolution; nitrene transfer; sulfoxides; sulfoximines