title: Asymmetric synthesis of new chiral N-sulfinyl 2,2-disubstituted aziridines by Grignard additions across alpha-chloro N-sulfinyl ketimines.
abstract: Reaction of chiral alpha-chloro N-tert-butanesulfinyl ketimines with Grignard reagents afforded new chiral N-sulfinyl 2,2-disubstituted aziridines in good to excellent diastereomeric ratio (dr up to 98 : 2). The 1,2,2-trisubstituted aziridines were isolated in high overall yield (51-85%) and with excellent enantiomeric excess (>98% ee). The stereoselectivity obtained in the Grignard addition is rationalized by the coordinating ability of the alpha-chloro atom resulting in the opposite stereochemical outcome as observed for nonfunctionalized N-sulfinyl ketimines.
authors.affiliation: Department of Organic Chemistry, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium.
authors.forename: Filip
authors.initials: F
authors.lastname: Colpaert
authors.forename: Sven
authors.initials: S
authors.lastname: Mangelinckx
authors.forename: Erika
authors.initials: E
authors.lastname: Leemans
authors.forename: Bram
authors.initials: B
authors.lastname: Denolf
authors.forename: Norbert
authors.initials: N
authors.lastname: De Kimpe
mesh_terms: D001388:Aziridines / Q000138:chemical synthesis* / Q000737:chemistry*; D002713:Chlorine / Q000737:chemistry*; D007097:Imines / Q000737:chemistry*; D009570:Nitriles / Q000737:chemistry*; D009584:Nitrogen / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D001388:Aziridines; D007097:Imines; D009570:Nitriles; C542835:ketimine; D002713:Chlorine; C033132:aziridine; D009584:Nitrogen