Asymmetric Aerobic Oxidation of alpha-Hydroxy Acid Derivatives Catalyzed by Reusable, Polystyrene-Supported Chiral N-Salicylidene Oxidovanadium tert-Leucinates

作者：Salunke Santosh B; Babu N Seshu; Chen Chien Tien^*

来源：Advanced Synthesis & Catalysis, 2011, 353(8): 1234-1240.

DOI：10.1002/adsc.201100062

• click chemistry
• direct immobilization
• enantioselective aerobic oxidation
• recyclable catalysts
• vanadyl compounds

The direct immobilization of two different C-5-propargyl ether-modified, chiral N-salicylidene vanadyl(V) tert-leucinates onto 4-azidomethyl-substituted polystyrene by click chemistry was examined. Among the eight different solvents investigated, the resulting polystyrene-supported catalysts promote the asymmetric, aerobic oxidation of a-hydroxy (thio) esters and amides with enantioselectivities of up to 99% ee (selectivity factor up to 41) in chloroform. These polystyrene-supported catalysts can be readily recovered by filtration and reused for at least four consecutive runs without discernible loss of reactivity and enantioselectivity.

• 出版日期2011-5
• 单位清华大学