A diastereoselective synthesis 1-trimethylsilyl-(E)-1,3-alkenynes and a simple synthesis of alkyl trimethylsilylethynyl ketones via organoboranes
作者:Narayan G. Bhat、Patricia Wawroski、Gonzalo Perez-Garcia、Mayra Elizondo
DOI:10.1016/j.tetlet.2005.05.134
日期:2005.8
A convenient, novel diastereoselective synthesis of 1-trimethylsilyl-(E)-1,3-alkenynes and a convenient synthesis of alkyl trimethylsilylethynyl ketones based on Z-1-bromo-1-alkenylboronate esters are developed. α-Bromo-(Z)-1-alkenylboronate esters readily available using literature procedures smoothly undergo a reaction with trimethylsilylethynyllithium (derived from the deprotonation of trimethylsilylethyne
开发了一种方便,新颖的非对映选择性合成1-三甲基甲硅烷基-(E)-1,3-炔烃和基于Z -1-溴-1-烯基硼酸酯的烷基三甲基甲硅烷基乙炔基酮的便利合成方法。使用文献方法容易获得的α-溴-((Z)-1-链烯基硼酸酯)在四氢呋喃中与三甲基甲硅烷基乙炔基锂(源自三甲基甲硅烷基乙炔与正丁基锂的去质子化)平稳反应,以提供相应的``酸酯''配合物。这些'ate'配合物经历分子内亲核取代反应以提供相应的(E含三甲基甲硅烷基乙炔基部分的)-1-链烯基硼酸酯,经乙酸质子分解后可提供相应的1-三甲基甲硅烷基-(E)-1,3-炔烃,收率好(70-82%),立体化学纯度高(> 98%) 。这些中间体用过氧化氢和乙酸钠氧化后,可提供相应的烷基三甲基甲硅烷基乙炔基酮,收率良好(66-78%)。