Phenylimido Complexes of Tungsten and Rhenium

The chemistry of organoimido compounds is currently of interest in studies of transition-metal multiple bonds. As a result of the robust M NR function, it has been possible to prepare imido complexes of a diversity of metals. For synthetic work with earlier transition metal complexes in high valence states, organoimido compounds are less likely to polymerize than species containing the terminal oxo group. An added advantage is that any polymeric compounds formed are likely to be soluble in organic solvents. 

Studies of the chemistry of phenylimido rhenium complexes have normally employed Re(NPh)Cl3(PPh3)2 as the starting material because of its easy preparation from aniline and the readily available compound ReOClj(PPh3)2. Tungsten imido complexes cannot be prepared similarly. The lack of good preparative methods leading to suitable starting materials has limited studies with this metal. 

Detailed below are procedures for preparing phenylimido tetrachloro complexes of tungsten and iheniumfVI) that are useful materials for further syntheses.  

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