Affiliation:
1. Yokohama National University, Graduate School of Engineering, Department of Materials Chemistry, Hodogaya-ku, Yokohama, Japan
2. Shanxi University, Department of Chemistry, Taiyuan, China
Abstract
The new trifluoroethoxo phosphine complexes [Cp2M(?1-dppe)(CF3CH2O)]+ and
[Cp2(CF3CH2O)M(?-dppe)MCp2(CF3CH2O)]2+ (M = Mo or W, Cp = ?-C5H5 and dppe =
Ph2PCH2CH2PPh2) have been prepared by reaction of cationic di-?-hydroxo
dinuclear complex of molybdenocene or tungstenocene [Cp2M(?-OH)2MCp2]2+ with
dppe. From the 1H and 31P NMR data, the configurations of the products could
be assigned. Furtheremore, X-ray crystallography was used to definitively
identify one of the product [Cp2(CF3CH2O)Mo(?-dppe)MoCp2(CF3CH2O)]2+, which
crystallizes in space group P21/c(#14) with a = 12.230(5) ?, b = 11.149(5)
?, c = 28.966(7) ?, ? = 101.07(3)?, V = 3876(2) ?3, and Z = 2. It was
ascertained that the amount of dppe added to the reaction mixture could
influence the product distribution. A mechanism involving initial
replacement of the hydroxo ligand by the alkoxo group followed by
nucleophilic attack of the phosphine is proposed on the basis of the
reaction profile.
Publisher
National Library of Serbia