Lu Guangfu, Xiao Liangrui, Que Qitao, Leng Tao, Li Jiuling, Guo Yafei, Fan Baomin
Yunnan Key Laboratory of Chiral Functional Substance Research and Application, Yunnan Minzu University, 2929 Yuehua Road, Kunming 650500, China.
J Org Chem. 2024 Jun 7;89(11):7573-7578. doi: 10.1021/acs.joc.4c00219. Epub 2024 May 23.
The catalytic asymmetric conjugate addition of phosphorus nucleophiles to unsaturated compounds, catalyzed by metallic or nonmetallic catalysts, has been extensively developed. However, the enantioselective transformations involving α,β-unsaturated carboxylic esters for constructing chiral c-p bonds have been rarely reported, particularly in metal-free processes. In this study, we present a novel metal-free methodology for enantioselective 1,4-addition of diarylphosphine oxides to α,β-unsaturated carboxylic esters using classical chiral oxazaborolidine catalysts. Remarkably high yields and enantioselectivities were obtained for most of the products. Furthermore, these valuable chiral phosphorus esters serve as crucial intermediates that can be transformed into various derivatives including amides, acids, and alcohols in a single step.
由金属或非金属催化剂催化的磷亲核试剂对不饱和化合物的催化不对称共轭加成反应已得到广泛发展。然而，涉及α,β-不饱和羧酸酯构建手性碳-磷键的对映选择性转化却鲜有报道，尤其是在无金属过程中。在本研究中，我们报道了一种使用经典手性恶唑硼烷催化剂，实现二芳基氧化膦对α,β-不饱和羧酸酯进行对映选择性1,4-加成的新型无金属方法。大多数产物都获得了极高的产率和对映选择性。此外，这些有价值的手性磷酯作为关键中间体，可以一步转化为包括酰胺、酸和醇在内的各种衍生物。
