Department of Chemistry, Sichuan University, Chengdu, China 610064.
J Org Chem. 2012 Jul 20;77(14):6215-22. doi: 10.1021/jo3009403. Epub 2012 Jul 5.
A class of alkenyl propargyl acetates, RCH(OAc)C≡CC(CH(3))═CH(2) (5), are found to undergo [4 + 1] cycloaddition with CO (1 atm) in the presence of RhCl(CO)(2) in refluxing 1,2-dichloroethane to give cyclopentenones (6) in good yields. It has been demonstrated that, when the R group of 5 is a phenyl group bearing o-electron-withdrawing substituents, up to 10:1 diastereoselectivity and 96% yield can be achieved for the [4 + 1] cycloaddition. This process provides a convenient method to construct highly functionalized cyclopentenones that are useful in organic synthesis.
一类烯基炔基乙酸酯，RCH(OAc)C≡CC(CH(3))═CH(2)（5），在[RhCl(CO)(2)]（2）存在下，在回流的 1,2-二氯乙烷中与 CO（1 大气压）发生[4+1]环加成反应，以良好的收率得到环戊烯酮（6）。已经证明，当 5 的 R 基团为带有吸电子取代基的苯基时，[4+1]环加成反应可以达到高达 10:1 的非对映选择性和 96%的产率。该过程提供了一种方便的方法来构建在有机合成中有用的高度官能化的环戊烯酮。
