Hydrogen Shift Reactions of Rhenium Hydrido Carbyne Complexes

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• 作者：Jiangxi Chen ; Chuan Shi ; Herman Ho-Yung Sung ; Ian Duncan Williams ; Zhenyang Lin ; Guochen Jia
• 刊名：Organometallics
• 出版年：2012
• 出版时间：March 12, 2012
• 年：2012
• 卷：31
• 期：5
• 页码：1817-1824
• 全文大小：490K
• 年卷期：v.31,no.5(March 12, 2012)
• ISSN：1520-6041

文摘

Rhenium hydrido carbyne complexes Re(鈮CH鈺怌(CMe₃)C鈮R)HCl(PMe₂Ph)₃ (R = H, n-pentyl) undergo 1,2-hydrogen shift reactions from the metal to the carbyne carbon atom to give complexes Re(HCCHC(CMe₃)CCR)HCl(PMe₂Ph)₃, which have two isomeric forms, namely, a metallabicyclo[3.1.0]hexatriene complex, in which the chloride is cis to the metal-bonded CH, and an alkyne鈥揷arbene complex, in which the chloride is trans to the metal-bonded CH. In contrast, a similar transformation does not occur for the analogous complex Re(鈮CH鈺怌(CMe₃)C鈮SiMe₃)HCl(PMe₂Ph)₃, which has a SiMe₃ group on the C鈮 moiety. A computational study suggests that the difference in the reactivity of the hydrido carbyne complexes is related to steric effects in the corresponding hydride-shift products. Formation of Re(HCCHC(CMe₃)CCSiMe₃)HCl(PMe₂Ph)₃ is not favored, mainly due to the steric interactions of the SiMe₃ group with CMe₃ and one of the phosphine ligands in the resulting metallabicyclo[3.1.0]hexatriene complex, and of the SiMe₃ group with the chloride ligand in the resulting alkyne鈥揷arbene complex.