Synthesis and some properties of 14 group element-containing alkylidene complexes of molybdenum and tungsten
- 作者：Leonid N. Bochkarev ; Yulia E. Begantsova ; Vladislav I. Shcherbakov ; Natalia E. Stolyarova ; Irina K. Grigorieva ; Irina P. Malysheva ; Galina V. Basova ; Andrey L. Bochkarev ; Yulia P. Barinova ; Georgii K.
- 关键词：Alkylidene complexes ; Molybdenum ; Tungsten ; Silicon ; Germanium ; Tin ; Synthesis ; Structure elucidation ; Olefin metathesis ; Catalytic activity
- 刊名：Journal of Organometallic Chemistry
- 出版年：2005
- 期刊代码：64_0022328x
- 类别：ch
- 出版时间：1 December 2005
- 卷：690
- 期：24-25
- 页码：5720-5727
- 文件大小：324 K
摘要
Alkylidene complex of molybdenum Ph3Si–CHMo(NAr)(OCMe2CF3)2 (1) has been prepared by the reaction of Ph3SiCHCH2 with known alkylidene compounds Alkyl-CHMo(NAr)(OCMe2CF3)2 (Alkyl = But, PhMe2C). According to X-ray diffraction studies the geometry of the Mo atom in (1) can be described as a distorted tetrahedron. Reactions of heteroelement-containing imido alkyl compounds of molybdenum and tungsten (ArN)2M(CH2EMe3)2 (; M = Mo. W; E = Si, Ge, Sn) with triflic acid were shown to yield a complex mixture of products among which carbene complexes have not been observed. The formation of carbene complexes of tungsten in low yields was observed by 1H NMR spectroscopy in the reactions of (ArN)2W(CH2EMe3)2 (E = Si, Ge, Sn) with hydrogen chloride in THF-d8. Catalytic properties of heteroelement-containing alkylidene complexes of molybdenum R3E–CHMo(NAr)(OCMe2CF3)2 (E = Si, Ge; R = Me, Ph) and also hydrocarbon analogs Alkyl-CHMo(NAr)(OCMe2CF3)2 (Alkyl = But, PhMe2C) in metathesis of 1-hexene were investigated. The catalytic activity of alkylidene complexes was shown to depend essentially on the nature of substituent bonded to carbene carbon atom.