Functionalisation of tetraalkylsilanes derived from CH activation; towards annulations of diterpenoids
作者:Paul W.R Harris、Clifton E.F Rickard、Paul D Woodgate
DOI:10.1016/s0022-328x(00)00059-0
日期:2000.4
Vinyl trialkylsilanes are efficient substrates for use in the ortho alkylation of aromatic ketones catalysed by zerovalent ruthenium complexes, giving, e.g. (2-trimethylsilylethyl)acetophenones. Methods for the selective desilylation–functionalisation of such tetraalkylsilanes are investigated. Some diterpenoid tetraalkylsilanes derived from the ruthenium-catalysed insertion of vinyltrimethylsilane
乙烯基三烷基硅烷是用于零价钌络合物催化的芳族酮的正烷基化的有效底物,可得到(2-三甲基甲硅烷基乙基)苯乙酮。研究了这种四烷基硅烷的选择性去甲硅烷基化-官能化的方法。某些钌衍生的乙烯基三甲基硅烷插入物衍生的二萜类四烷基硅烷已通过将ArCH 2 CH 2 SiMe 3片段与NaBrO 3 -Na 2 S 2 O 5(最佳)进行苄基溴化作用而官能化,从而生成1,2-二溴乙基衍生物。进一步的转化最终导致ArCH 2的整体转化CH 2 SiMe 3转化为ArCOCH 3。尝试的1,4-二酮的羟醛偶联引起了骨骼的重组。在氯化铝和水的作用下,四烷基硅烷被转化为硅烷醇(ArCH 2 CH 2 SiMe 2 OH),但是这种硅烷醇进一步氧化为伯醇(ArCH 2 CH 2 OH)是不成功的。