Control of Selectivity through Synergy between Catalysts, Silanes, and Reaction Conditions in Cobalt-Catalyzed Hydrosilylation of Dienes and Terminal Alkenes
作者:Balaram Raya、Stanley Jing、Vagulejan Balasanthiran、T. V. RajanBabu
DOI:10.1021/acscatal.6b03373
日期:2017.4.7
with 2 equiv of NaEt3BH at −78 °C in toluene to generate a catalyst that effects highly selective anti-Markovnikov hydrosilylation of the terminal double bond in 1,3- and 1,4-dienes. Primary and secondary silanes such as PhSiH3, Ph2SiH2, and PhSi(Me)H2 react with a broad spectrum of terminal dienes without affecting the configuration of the other double bond. When dienes conjugated to an aromatic ring
易获得的(i- Pr PDI)CoCl 2 [ i- Pr PDI = 2,6-双(2,6-二异丙基苯基亚氨基乙基)吡啶]在-78°C下与2当量的NaEt 3 BH在甲苯中反应生成催化剂,该催化剂在1,3-和1,4-二烯中的末端双键的高选择性抗Markovnikov氢化硅烷化作用。伯硅烷和仲硅烷,例如PhSiH 3,Ph 2 SiH 2和PhSi(Me)H 2与多种末端二烯发生反应,而不会影响另一个双键的构型。当涉及与芳族环共轭的二烯时,既形成马尔可夫尼可夫产物又形成反马尔可夫尼可夫产物。该反应可耐受各种官能团,例如芳基溴化物,芳基碘化物,受保护的醇,甚至甲硅烷基烯醇醚。1-烯烃在相似条件下的反应干净地导致了马尔可夫尼可夫和抗马尔可夫尼可夫氢化硅烷化产物的混合物,其中产物的比例随着亚氨基芳基中2,6-取代基的尺寸变大而越来越有利于后者。配合物(i- Pr PDI)CoCl 2仅提供用于各种