title: Rhodium-catalyzed stereoselective amination of thioethers with N-mesyloxycarbamates: DMAP and bis(DMAP)CH(2)Cl(2) as key additives.
abstract: A stereoselective Rh-catalyzed intermolecular amination of thioethers using a readily available chiral N-mesyloxycarbamate to produce sulfilimines in excellent yields and diastereomeric ratio is described. A catalytic mixture of 4-dimethylaminopyridine (DMAP) and bis(DMAP)CH2 Cl2 proved pivotal in achieving high selectivity. The X-ray crystal structure of the (DMAP)2 ⋅[Rh2 {(S)-nttl}4 ] complex was obtained and mechanistic studies suggested a Rh(II) -Rh(III) complex as the catalytically active species.
authors.affiliation: Département de Chimie, Center for Green Chemistry and Catalysis, Université de Montréal, C.P. 6128, Succ. Centre-ville, Montréal, Québec, H3C 3J7 Canada. helene.lebel@umontreal.ca.
authors.forename: Hélène
authors.initials: H
authors.lastname: Lebel
authors.forename: Henri
authors.initials: H
authors.lastname: Piras
authors.forename: Johan
authors.initials: J
authors.lastname: Bartholoméüs
keywords: asymmetric catalysis; chiral sulfilimines; metal nitrenes; rhodium; sulfoximines