Imido and oxo compounds of chromium-(V) and -(VI) and of molybdenum- and tungsten-(VI)

摘要: The interaction of 1,1,1,3,3,3-hexamethyldisilazane and CrO2Cl2 gives the amido complex CrO2[N(SiMe3)2] whereas MoO2Cl2 imido Mo(NSiMe3)2(OSiMe3)2 WO2Cl2(dme)(dme = 1,2-dimethoxyethane) a red oil that reacts with pyridine (py) to give WCl(NSiMe3)(OSiMe3)3(py). Interaction 4-methylpyridine (L) leads reduction chromium(V) species [CrO(NSiMe3)L]2(µ-OSiMe3)2. 2,2,6,6-tetramethyl-piperidine CrO2Cl(NC9H18) while SiMe2(NHBut)2 Cr(NBut)2Cl2(NH2But). crystal structures compounds [CrO(NSiMe3)(py)]2(µ-OSiMe3)2, WCl(NSiMe3)(OSiMe3)3(py) have been determined. In centrosymmetric dimeric Cr atom is five-co-ordinate geometry intermediate between trigonal bipyramidal square pyramidal. crystals contain two chemically equivalent tetrahedral molecules, WCl(NSiMe3)(OSiMe3)(py) octahedral ligand trans group.