Synthesis of bicyclic γ-butyrolactone derivatives by rhodium catalyzed intramolecular C–H insertion of α-dizao α-phosphoryl cycloalkyl esters
作者:Jr-Yun Shie、Jia-Liang Zhu
DOI:10.1016/j.tet.2016.02.008
日期:2016.3
products can be further elaborated into α,α-dialkyl γ-butyrolactones via a two-step alkylation/reductive alkylation sequence with the controlled installation of two alkyl groups to the lactones. In addition, application of Horner–Wadsworth–Emmons (HWE) olefination reaction to the insertion products allows an access to bicyclic α-alkylidene-γ-butyrolactone ring systems that occur ubiquitously in biologically
在Rh 2(OAc)4的催化下,几种容易制备的环烷基α-重氮α-磷酸酯经过分子内C–H插入反应,以不同的收率(10%–80%)和dr比率(69:14: 17至> 99:1)。实验结果表明,前体的反应性和环化的非对映选择性都受环烷基部分的环大小的影响。而且,大多数得到的产物可以通过两步烷基化/还原烷基化序列在受控地将两个烷基安装到内酯上而进一步加工成α,α-二烷基γ-丁内酯。此外,