title: Enantioselective radical alkynylation of C(sp(3) )-H bonds using sulfoximine as a traceless chiral auxiliary.
abstract: Enantioselective alkynylation of C(sp(3) )H bonds adjacent to a nitrogen atom has been achieved using only chiral p-tolyl tert-butyldimethylsilylethynyl sulfoximine and benzophenone under photo-irradiation conditions. A two-carbon alkyne unit was chemo- and enantioselectively transferred at the nitrogen-substituted methylene to produce the optically active propargylic amines of various structures. Remarkably, the NH-unprotected sulfoximine group efficiently transmits its stereochemical information to the product and functions as a traceless chiral auxiliary.
authors.affiliation: Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan).
authors.forename: Masanori
authors.initials: M
authors.lastname: Nagatomo
authors.forename: Shun
authors.initials: S
authors.lastname: Yoshioka
authors.forename: Masayuki
authors.initials: M
authors.lastname: Inoue
keywords: alkynes; amines; enantioselectiveity; photochemistry; radical reactions