手性噁唑啉-Ti((Ⅳ)配合物催化硫醚的不对称氧化反应研究

The Asymmetric Oxidation of Sulfides Catalyzed by Chiral Oxazoline-Ti(Ⅳ) Complexes

设计合成了系列唑啉 -Ti( Oi Pr) 4配合物催化剂 ,首次成功地用这类催化剂催化一系列硫醚的不对称氧化 ,获得了 e.e.值为 70 %～ 96%的亚砜 ;考察了溶剂、催化剂用量。

A series of new chiral oxazoline Ti(O i Pr) 4 complexes were synthesized, which were firstly and successfully applied to the catalytic asymmetric oxidation of sulfides and resulted in chiral sulfoxides. The reactivity and enantioselectivity were strongly influenced by the structure of the oxazolines. When (4 S,5S ) 4,5 dihydro 4,5 diphenyl 2 (2 hydroxy 3 tert butylphenyl) oxazoline was used as the ligand, 2.0 mol of TBHP was used in the oxidation of methyl phenyl sulfide, the sulfoxide was obtained in 96% e.e. . The influence of solvent, amount of catalyst, counterion and other conditions on the reaction was also investigated.