Transition Metal-Catalyzed Addition Reaction to Alkynylmetals with Migration of Metal Moieties

过渡金属催化的炔基金属加成反应以及金属部分的迁移

• 批准号: 17550100
• 负责人: SHIRAKAWA Eiji
• 金额: $ 2.3万
• 依托单位: Kyoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-17550100/
• 关键词: transition metal catalyst; alkynylmetal; addition reaction; ruthenium; alkyne; alkynylstannane

In the presence of a catalytic amount of a ruthenium complex coordinated with PBu_3, alkynylstannanes (R^1C≡CSnBu_3) were found to accept the addition of terminal alkynes (R^2C=CH) with 1, 2-shift of the stannyl group to give (E)-and (Z)-1-tributylstannylbut-1-en-3-ynes (Bu_3SnC(R^1)=CHC=CR^2). The addition reaction is applicable to various combination of substrates having an aromatic and/or aliphatic substituent, the stereochemical outcome depending largely on the character of these substituents. The reaction of aliphatic terminal alkynes proceeds in perfect stereoselectivities, where substituent R^1 on alkynylstannanes determines the configuration : E for R^1 = alkyl and Z for R^1 = aryl. In contrast, the reaction of arylacetylenes gave a mixture of stereoisomers irrespective of the character of substituent R^1 on the alkynylstannane. Ruthenium-β-stannylvinylidene complexes generated from a ruthenium complex and an alkynylstannane with migration of the stannyl group is likely to be involved in the reaction as key intermediates, which accept addition of a C-H bond of terminal alkynes to give the corresponding stannylenynes. DFT calculation clearly shows that the 1, 2-shift of the stannyl group on formation of ruthenium-β-stannylvinylidene complexes is more facile than the corresponding 1, 2-hydrogen shift of the coordinating terminal alkynes. The effect of substituents on the stereoselectivity also is discussed based on the calculation.

在催化量的PBu_3配位的钌配合物存在下，炔基锡烷（R^1C = CSnBu_3）与端炔（R^2C=CH）发生加成反应，锡基发生1，2-位移，生成（E）-和（Z）-1-三丁基锡基丁-1-烯-3-炔（Bu_3SnC（R^1）=CHC=CR^2）.加成反应适用于具有芳族和/或脂族取代基的底物的各种组合，立体化学结果在很大程度上取决于这些取代基的性质。脂肪族末端炔的反应以完美的立体选择性进行，其中炔基锡烷上的取代基R^1决定了构型：R^1的E =烷基，R^1的Z =芳基。与此相反，芳基乙炔的反应得到了立体异构体的混合物，而与炔基锡烷上取代基R^1的性质无关。由钌配合物和炔基锡烷通过锡烷基的迁移生成的钌-β-锡烷基亚乙烯基配合物可能作为关键中间体参与反应，其接受末端炔的C-H键加成以得到相应的锡烯炔。密度泛函理论计算表明，钌-β-锡烷基亚乙烯基配合物形成过程中锡基的1，2-位移比端炔的1，2-氢位移更容易发生.在计算的基础上讨论了取代基对立体选择性的影响。

项目成果

Ruthenium-Catalyzed Addition of Alkynes to Alkynylstannanes with Migration of the Stannyl Group

钌催化炔烃与炔基锡烷的加成以及锡烷基团的迁移

• 发表时间: 2006
• 期刊: Bulletin of Chemical Society Japan 79・12
• 作者: 竹内敬一;武田琢磨;藤本哲也;山本巖;白川英二
• 通讯作者: 白川英二