NEW SYNTHESES OF TUNGSTEN (Ⅳ) HALIDES AND THEIR ADDUCTS WITH NITROGEN AND SULFUR DONOR LIGADS CHARACTERIZATION BY VIBRATIONAL SPECTROSCOPY AND STUDY OF MAGNETIC PROPERTIES

摘要

A method was developed for synthesis of tungsten(V) and tungsten(IV) chloride. Tungsten hexacarbonyl was used to reduce higher valent chlorides under mild conditions.nUtilizing the tungsten tetrachloride prepared by this method a series of tungsten(IV) complexes (WCl4L2) were pre¬pared. The ligands used were nitriles, pyridine, aliphatic sulfides, triphenylphosphine, and bipyridine.nThe complexes were characterized by use of room temperature and low temperature infrared spectra. The stereochemistry of the complexes was assigned by study of the tungsten-chloride stretching frequencies.nThe paramagnetic shifts in the nmr spectra were recorded for several complexes. The behavior of these shifts was found to be quite complicated and little interpretation of the data could be made.