Institute of Petrochemistry and Catalysis, Russian Academy of Sciences, Ufa, Russian Federation.
Steroids. 2013 Feb;78(2):241-6. doi: 10.1016/j.steroids.2012.11.012. Epub 2012 Dec 5.
Cycloalumination of 3'-methylene-(5α)-spirocholestane-3,1'-cyclobutane with triethylaluminum catalyzed by Cp(2)ZrCl(2) was accomplished for the first time to give (5α)-spirocholestane-3,1'-(6'-ethyl-6'-aluminaspiro [3.4] octane) in 89%. The latter, without isolation, was converted into spirotetrahydroselenophene or spirotetrahydrofuran.
首次使用 Cp(2)ZrCl(2) 催化三乙基铝环丙化 3'-亚甲基-(5α)-螺[5.5]十一烷-3,1'-环丁烷,得到(5α)-螺[5.5]十一烷-3,1'-(6'-乙基-6'-铝螺[3.4]辛烷),产率为 89%。后者无需分离,即可转化为螺[四氢]硒吩或螺[四氢]呋喃。