Synthesis and characterization of diorganohydrazido(2-) tungsten complexes.

Diorganohydrazido(2-) complexes of tungsten (L)Cl4W(NNR2) [R2=Me2, Ph2, -(CH2)5-; L=CH3CN, pyridine] were synthesized by reacting the corresponding 1,1-diorganohydrazine with WCl6, followed by reaction with acetonitrile or pyridine. Crystallographic structure determination of (CH3CN)Cl4W(NNMe2) and (CH3CN)Cl4W(NNPh2) allows a comparison of the structural features of the diorganohydrazido(2-) functionality with varying substituents. Mass spectrometry, thermogravimetric analysis, and preliminary chemical vapor deposition experiments were performed to determine the viability of these complexes as single-source precursors for deposition of WNx and WNxCy films.