The synthesis and reactivity of new niobium (V) polyhydrides

• Main Author: Olson, Wendy A.
• Format: Others
• Language: en
• Published: 1983
• Online Access: https://thesis.library.caltech.edu/5757/1/Olsen_w_1983.pdf; Olson, Wendy A. (1983) The synthesis and reactivity of new niobium (V) polyhydrides. Master's thesis, California Institute of Technology. doi:10.7907/e6p9-e788. https://resolver.caltech.edu/CaltechTHESIS:04292010-145411166 <https://resolver.caltech.edu/CaltechTHESIS:04292010-145411166>

The synthesis of new niobium polyhydrides by high pressure hydrogenation of Cp*NbMe_4 in the presence of trapping phosphines is reported. The complexes Cp*NbL_2H_4, L=PMe_3, PMe_2Ph, PMe_2Cy, and L_2=bis(dimethylphosphino)ethane, are described. They exchange D_2 into the hydride positions, and react hydridically with methanol and acetone to give alkoxide species. Reactions with CO give reduced metal carbonyl phosphine complexes. All these reactions (except the reaction with methanol) appear to proceed with loss of phosphine as the rate limiting step. Reactions of the hydride species with group VI carbonyls, and with ethylene, are presented. The novel reactivity of Cp*Nb(PMe_2Ph)_2H_4 with H_2 to give Cp*Nb(PMe_2Cy)_2H_4 is discussed.