Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, P. R. China.
J Am Chem Soc. 2012 Oct 17;134(41):17023-6. doi: 10.1021/ja309262f. Epub 2012 Oct 3.
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.
在手性 N,N'-二氧化物-钪(III)配合物催化剂的存在下，实现了外消旋和内消旋环状酮的催化对映选择性 Baeyer-Villiger（BV）氧化。前手性环己酮和环丁酮的 BV 氧化分别以高达 99%的收率和 95%的对映体过量值得到了一系列光学活性的ε-和γ-内酯。同时，通过异常的 BV 氧化也实现了外消旋 2-芳基环己酮的动力学拆分。优先得到了形成与迁移能力相反的非对映富集的 3-芳基环氧庚-2-酮。所得内酯和未反应的酮均具有高的对映体过量值。
