<i>C</i>
<sub>3</sub>
‐Symmetric Trisimidazoline‐Catalyzed Enantioselective Bromolactonization of Internal Alkenoic Acids
作者:Kenichi Murai、Akira Nakamura、Tomoyo Matsushita、Masato Shimura、Hiromichi Fujioka
DOI:10.1002/chem.201200647
日期:2012.7.2
A method for conducting enantioselective bromolactonization reactions of trisubstituted alkenoic acids, using the C3‐symmetric trisimidazoline 1 and 1,3‐dibromo‐5,5‐dimethyl hydantoin as a bromine source, has been developed. The process generates chiral δ‐lactones that contain a quaternary carbon. The results of studies probing geometrically different olefins show that (Z)‐olefins rather than (E)‐olefins
已开发出一种使用C 3对称的三咪唑啉1和1,3-二溴-5,5-二甲基乙内酰脲作为溴源进行三取代链烯酸的对映选择性溴化反应的方法。该过程会生成含有季碳的手性δ-内酯。研究几何上不同的烯烃的研究结果表明,(Z)-烯烃而不是(E)-烯烃是该工艺的理想底物。该方法不仅适用于无环烯烃反应物,还可以用于将环状三取代烯烃转化为手性螺环内酯。最后,通过将其应用于抗真菌海洋天然产物tanikolide的简明合成中,证明了该新工艺的合成效用。