Reversible Insertion of Carbenes into Ruthenium鈥揝ilicon Bonds
详细信息 查看全文
- 作者：Mar铆a J. Bernal ; Olga Torres ; Marta Martı ; ́ ; n ; Eduardo Sola
- 刊名：Journal of the American Chemical Society
- 出版年：2013
- 出版时间：December 18, 2013
- 年：2013
- 卷：135
- 期：50
- 页码：19008-19015
- 全文大小：424K
- 年卷期：v.135,no.50(December 18, 2013)
- ISSN：1520-5126
文摘
The five-coordinate carbene complexes [Ru{魏P,P,Si-Si(Me)(C6H4-2-PiPr2)2}Cl(鈺怌HR)] (2, R = Ph; 3, R = SiMe3), analogues of the Grubbs catalyst, were prepared from the dimer [Ru(渭-Cl){魏P,P,Si-Si(Me)(C6H4-2-PiPr2)2}]2 (1) and the corresponding diazoalkane N2CHR. The particular structural features that result from the presence of a strongly trans directing silyl group at the pincer ligand of these complexes are discussed on the basis of NMR information and the crystal structure of the vinylidene analogue [Ru{魏P,P,Si-Si(Me)(C6H4-2-PiPr2)2}Cl(鈺怌鈺怌HPh)] (4), which was also obtained from 1 and phenylacetylene. The reactions of 3 with reagents such as P(OMe)3, CO, NCMe, and K(acac) illustrate that the first response of these carbene complexes to an increase of the coordination number around ruthenium is the insertion of the carbene ligand into the Ru鈥揝i bond. These reactions also indicate that the insertion process is reversible and allows typical transformations of carbene ligands such as C鈥揌 functionalizations via carbene insertion (in the acac ligand) or the formation of ketene from CO. In addition, the reactions of 3 with terminal alkynes such as phenylacetylene or 3,3-dimethyl-1-butyne show that the inserted carbenes can also undergo reactions typical of metal-bound alkyls such as alkyne insertion and C鈥揌 reductive elimination.