New details concerning the reactions of nitric oxide with vanadium tetrachloride

The slow addition of NO to a CCl4 solution Of VCl4 reproducibly forms the known polymer [V(NO)(3)Cl-2](n) as a dark brown powder. Treatment of a CH2Cl2 suspension of [V(NO)(3)Cl-2], with excess THF generates mer-(THF)(3)V(NO)Cl-2 (1) which can be isolated as an orange crystalline material in 55% yield. The reaction of 1 with excess MeCN or 1 equiv of trimpsi (trimpsi = (BuSi)-Bu-t(CH2PMe2)(3)) provides yellow-orange (MeCN)(3)V(NO)Cl-2.MeCN (2.MeCN) and yellow (trimpsi)V(NO)Cl-2 (3), respectively. A black, crystalline complex formulated as [NO][VCl5] (4) is formed by the slow addition of NO to neat VCl4 or by the reaction of excess CINO with neat VCl4. Complex 4 is extremely air- and moisture-sensitive, and IR spectroscopy suggests that in solutions and in the gas phase it dissociates back into VCl4 and CINO. Reaction of 4 with excess [NEt3(CH2Ph)]Cl generates [NEt3(CH2Ph)](2)[VCl6].2CH(2)Cl(2) (5.2CH(2)Cl(2)), which can be isolated as deep-red crystals in 51% yield. All new complexes have been characterized by conventional spectroscopic methods, and the solid-state molecular structures of 1, 2.MeCN, and 5.2CH(2)Cl(2) have been established by single-crystal X-ray diffraction analyses.