Use of alpha-chlorinated N-(tert-butanesulfinyl)imines in the synthesis of chiral aziridines.
[reaction: see text] Reaction of chiral alpha-chloro tert-butanesulfinyl aldimines with Grignard reagents efficiently afforded beta-chloro N-sulfinamides in high diastereomeric excess. The latter compounds were cyclized toward the corresponding chiral aziridines in a high-yielding one-pot reaction or after separate treatment with base. The diastereoselectivity obtained in the newly synthesized beta-chloro sulfinamides is explained via the coordinating ability of the alpha-chloro atom with magnesium resulting in the opposite stereochemical outcome as generally observed for nonfunctionalized N-sulfinyl imines.
Denolf
Bram
B
Department of Organic Chemistry, Faculty of Bioscience Engineering, Ghent University, Belgium.
Mangelinckx
Sven
S
Törnroos
Karl W
KW
De Kimpe
Norbert
N