The asymmetric oxidation of sulfides catalyzed by chiral oxazoline-Ti(IV) complexes

A series of new chiral oxazoline-Ti (O Tr-i)(4) complexes were synthesized, which were firstly and successfully applied to the catalytic asymmetric ox idation of sulfides and resulted in chiral sulfoxides. The reactivity and e nantioselectivity were strongly influenced by the structure of the oxazolin es. When (4S, 5S)-4,5-dihydro-4,5-diphenyl-2-(2 ' -hydroxy-3 ' -tert-butylp henyl) oxazoline was used as the figand, 2. 0 mol of TBHP was used in the o xidation of methyl phenyl sulfide, the sulfoxide was obtained in 96% e. e.. The influence of solvent, amount of catalyst, counterion and other conditi ons on the reaction was also investigated.