过渡金属催化的 1,6-二炔环化/氢化硅烷化是制备五元环稠合甲硅烷基二烯的有用方法,五元环稠合甲硅烷基二烯是有机合成中有用的试剂。只有少数促进这种转化的贵金属催化剂是已知的,而影响该反应的非贵金属催化剂仍然难以捉摸。在此,我们报道低配位Co(0)-N-杂环卡宾配合物可以催化1,6-二炔与叔氢和仲氢硅烷的环化/氢化硅烷化,提供五元环稠合( Z )-1-甲硅烷基二烯具有良好的产率和优异的立体选择性。机理研究表明催化循环很可能以Co(0)物种的1,6-二炔氧化环化为关键步骤。该机制解释了钴催化环化/氢化硅烷化反应中的高立体选择性且不存在未环化的氢化硅烷化副产物,这与贵金属催化反应的氢化硅烷化-环化机理不同。
Cyclization/Hydrosilylation of Functionalized Diynes Catalyzed by a Cationic Platinum Phenanthroline Complex
作者:James W. Madine、Xiang Wang、Ross A. Widenhoefer
DOI:10.1021/ol006901u
日期:2001.2.1
[figure: see text] A 1:1 mixture of the platinum phenanthroline complex (phen)PtMe2 and B(C6F5)3 catalyzed the cyclization/hydrosilylation of functionalized 1,6- and 1,7-diynes to form silylated 1,2-dialkylidenecycloalkanes in good yield and with high Z-selectivity.
Cyclization/Hydrosilylation of Functionalized 1,6-Diynes Catalyzed by Cationic Platinum Complexes Containing Bidentate Nitrogen Ligands
作者:Xiang Wang、Harinath Chakrapani、James W. Madine、Michele A. Keyerleber、Ross A. Widenhoefer
DOI:10.1021/jo015986p
日期:2002.5.1
and HSiEt(3) to form 1,1-dicarbomethoxy-3-methylene-4-(triethylsilylmethylene)cyclopentane (3) in 82% isolated yield with 26:1 Z:E selectivity. Platinum-catalyzed diyne cyclization/hydrosilylation tolerated a range of functional groups including esters, sulfones, acetals, silyl ethers, amides, and hindered ketones. Diynes that possessed propargylic substitution underwent facile cyclization/hydrosilylation
Cobalt-Catalyzed Cyclization/Hydrosilylation Reaction of 1,6-Diynes Enabled by an Oxidative Cyclization–Hydrosilylation Mechanism
作者:Jiaxing Dong、Xuebing Leng、Dongyang Wang、Liang Deng
DOI:10.1021/acscatal.4c00473
日期:2024.3.15
preparation of five-membered ring-fused silyl dienes that are useful reagents in organic synthesis. Only a handful of noble metal catalysts facilitating this transformation are known, and nonprecious metal catalysts effecting the reaction have remained elusive. Herein, we report that low-coordinate Co(0)-N-heterocyclic carbene complexes can catalyze the cyclization/hydrosilylation of 1,6-diynes with tertiary
过渡金属催化的 1,6-二炔环化/氢化硅烷化是制备五元环稠合甲硅烷基二烯的有用方法,五元环稠合甲硅烷基二烯是有机合成中有用的试剂。只有少数促进这种转化的贵金属催化剂是已知的,而影响该反应的非贵金属催化剂仍然难以捉摸。在此,我们报道低配位Co(0)-N-杂环卡宾配合物可以催化1,6-二炔与叔氢和仲氢硅烷的环化/氢化硅烷化,提供五元环稠合( Z )-1-甲硅烷基二烯具有良好的产率和优异的立体选择性。机理研究表明催化循环很可能以Co(0)物种的1,6-二炔氧化环化为关键步骤。该机制解释了钴催化环化/氢化硅烷化反应中的高立体选择性且不存在未环化的氢化硅烷化副产物,这与贵金属催化反应的氢化硅烷化-环化机理不同。