One-Step Synthesis of Triethynylvinylmethanes and Tetraethynylmethanes by GaCl<sub>3</sub>-Promoted Diethynylation of 1,4-Enynes and 1,4-Diynes
作者:Ryo Amemiya、Katsunori Suwa、Junji Toriyama、Yoshio Nishimura、Masahiko Yamaguchi
DOI:10.1021/ja051416l
日期:2005.6.1
allylsilanes with the chloroacetylene also gave diethynylvinylmethanes, in which 1,4-enynes were formed in situ by the addition-elimination of allylgallium formed from allylsilane and GaCl3. Tetraethynylmethanes were obtained by reacting 1,4-diynes with the chloroacetylene at 150 degrees C. The structure and amount of silanol can be used to control the reactivity of GaCl3.
在 GaCl3 存在下,在 130 摄氏度下用氯三乙基甲硅烷基乙炔处理 1,4-烯炔,通过烯丙基亚甲基部分的二乙炔化作用得到三乙炔基乙烯基甲烷。2,6-二(叔丁基)-4-甲基吡啶和叔丁基二苯基硅烷醇的加入通过减少底物和产物的分解显着提高了产物的产率。该反应应包括烯炔和 GaCl3 最初形成烯丙基镓,其中 GaCl3 活化烃 CH 以生成亲核有机镓中间体。用氯乙炔进行碳金属化,然后进行 β-消除,然后得到乙炔化产物。三乙炔基乙烯基甲烷是通过在烯炔的 3 位重复区域选择性乙炔化获得的。烯丙基硅烷与氯乙炔的反应也产生二乙炔基乙烯基甲烷,其中通过由烯丙基硅烷和 GaCl3 形成的烯丙基镓的加成消除原位形成 1,4-烯炔。四乙炔甲烷是通过 1,4-二炔与氯乙炔在 150 摄氏度下反应获得的。硅烷醇的结构和数量可用于控制 GaCl3 的反应性。