A Redox-Reconfigurable, Ambidextrous Asymmetric Catalyst

作者：Mortezaei Shahab; Catarineu Noelle R; Canary James W^*

来源：Journal of the American Chemical Society, 2012, 134(19): 8054-8057.

DOI：10.1021/ja302283s

A redox-reconfigurable catalyst derived from L-methionine and incorporating catalytic urea groups has been synthesized. This copper complex catalyzes the enantioselective addition of diethyl malonate to trans-beta-nitrostyrene. Either enantiomer of the product can be predetermined by selection of the oxidation state of the copper ion. Enantiomeric excesses of up to 72% (S) and 70% (R) were obtained in acetonitrile. The ability of the catalyst to invert enantiomeric preference was reproduced with several different solvents and bases. Facile interconversion between the Cu2+ and Cu+ redox states allowed easy access to both active helical forms of the complex and, therefore, dial-in enantioselectivity.

• 出版日期2012-5-16