Some Aspects Of The Organometallic Chemistry Of The Group Vi Transition Metals

Download or read book Some Aspects of the Organometallic Chemistry of the Group VI Transition Metals written by Ezra Eddy Isaacs and published by . This book was released on 1974 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The reaction of cycloheptatrienyltricarbonyl molybdenum cation with various main group V donor ligands (L) yielded, in general, mono-substituted complexes, [C[subscript 7]H[subscript 7]Mo(CO)[subscript 2]L][superscript +]. [superscript 31]P nmr studies on some related di-tertiary phosphine complexes provided a convenient and unequivocal determination of the stereochemistry. The reduction of the cationic cycloheptatrienyl complexes with sodium borohydride provided a suitable synthetic route to the group V derivatives of cyclo- heptatrienetricarbonylmolybdenum. The infrared, [superscript l]H and [superscript 13]C nmr, and mass spectral properties of these complexes were studied. Some main group IV ligands bonded to cycloheptatrienyldicarbonylmolybdenum were also prepared and studied by spectral means. A number of main group IV - group VI metal penta- carbonyl anionic derivatives have been prepared by the reaction of the chloropentacarbonyl anions with the organolithium compounds of the group IV elements. These compounds have the general formula, [R[subscript 3]M' -M(CO)[subscript 5]][superscript -] (where R = Me, Ph or halogen; M' = Si, Ge, Sn or Pb; M = Cr, Mo or W). Approximate carbonyl force constants were calculated from the infrared carbonyl stretching vibrations and these provided some insight into the nature of the metal-metal bonds. Transition metal nitrosyl derivatives have also been prepared by the reaction of some anionic complexes with nitrosonium hexafluorophosphate. These compounds have the general formula LM(CO)[subscript 4]NO (where L is a main group IV ligand or a halogen group and M is Mo or W). The carbonyl and nitrosyl force constants were calculated and are discussed in terms of the relative bonding properties of CO and NO ligands. Finally, the oxidation reaction of some dinuclear metal carbonyls with AgNO[subscript 2] led to the formation of metal carbonyls containing nitro ligands. Linkage isomerism involving nitro and nitrito species was encountered in solution. The [(CH[subscript 3]CN)[subscript 3]Re(CO)[subscript 3]] + cation was formed 2 - from the oxidation reaction of [Re[subscript 4](CO)[subscript 16]][superscript 2-] in acetonitrile.