title: Hypervalent Iodine(V)-Induced Asymmetric Oxidation of Sulfides to Sulfoxides Mediated by Reversed Micelles: Novel Nonmetallic Catalytic System.
abstract: Although several types of chiral hypervalent iodine reagents have been used for asymmetric induction, all of them have needed more than a stoichiometric amount of chiral reagents and have shown low enantioselectivities. The described new catalytic asymmetric oxidation using a hypervalent iodine(V) reagent, iodoxybenzene (PhIO(2)), in a cationic reversed micellar system provides the first example of a catalytic asymmetric oxidation of sulfides to sulfoxides in high chemical yield with moderate to good enantioselectivity without the use of any transition-metal catalysts. The solubilization and activation of PhIO(2) by adding catalytic amounts of both cetyltrimethylammonium bromide (CTAB) and a chiral tartaric acid derivative were found to be indispensable for the enhancement of chemical and optical yields.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamada-oka, Suita, Osaka 565-0871, Japan.
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Tohma
authors.forename: Shinobu
authors.initials: S
authors.lastname: Takizawa
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Watanabe
authors.forename: Yuko
authors.initials: Y
authors.lastname: Fukuoka
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Maegawa
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Kita