Enantioselective Aerobic Oxidation of 伪-Hydroxy-Ketones Catalyzed by Oxidovanadium(V) Methoxides Bearing Chiral, N-Salicylidene-tert-butylglycinates

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• 作者：Chien-Tien Chen ; Jun-Qi Kao ; Santosh B. Salunke ; Ya-Hui Lin
• 刊名：Organic Letters
• 出版年：2011
• 出版时间：January 7, 2011
• 年：2011
• 卷：13
• 期：1
• 页码：26-29
• 全文大小：201K
• 年卷期：v.13,no.1(January 7, 2011)
• ISSN：1523-7052

文摘

Chiral oxidovanadium(V) methoxides prepared from 3,5-disubstituted-N-salicylidene-l-tert-butylglycines and vanadyl sulfate in air-saturated MeOH serve as highly enantioselective catalysts for asymmetric aerobic oxidations and kinetic resolution of alkyl, aryl, and heteroaryl 伪-hydroxy-ketones with differed 伪-substituents at ambient temperature in toluene or TBME (tert-butyl methyl ether). The best scenarios involve the use of complexes which bear the tridendate templates derived from 3,5-diphenyl- or 3-o-biphenyl-5-nitro-salicyaldehyde. The kinetic resolution selectivities of the aerobic oxidation process are in the range of 12 to >1000 based on the selectivity factors (k_rel).