Enantioselective Baeyer-Villiger oxidation: desymmetrization of meso cyclic ketones and kinetic resolution of racemic 2-arylcyclohexanones.
نویسندگان
چکیده
Catalytic enantioselective Baeyer-Villiger (BV) oxidations of racemic and meso cyclic ketones were achieved in the presence of chiral N,N'-dioxide-Sc(III) complex catalysts. The BV oxidations of prochiral cyclohexanones and cyclobutanones afforded series of optically active ε- and γ-lactones, respectively, in up to 99% yield and 95% ee. Meanwhile, the kinetic resolution of racemic 2-arylcyclohexanones was also realized via an abnormal BV oxidation. Enantioenriched 3-aryloxepan-2-ones, whose formation is counter to the migratory aptitude, were obtained preferentially. Both the lactones and the unreacted ketones were obtained with high ee values.
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ورودعنوان ژورنال:
- Journal of the American Chemical Society
دوره 134 41 شماره
صفحات -
تاریخ انتشار 2012