RT info:eu-repo/semantics/article
T1 Mixed-dicyclopentadienyl niobium and tantalum complexes: synthesis and reactivity X-ray molecular structures of Ta(η-C5Me5)(η5-C5H4SiMe3)Cl2 and Ta(η5-C5Me5){η5-C5H3(SiMe3)2}H3
A1 Castro Correro, Aurora
A1 Gómez Rubio, Manuel
A1 Gómez Sal, Pilar
A1 Manzanero Castillo, Antonio
A1 Royo Gracia, Pascual
K1 Niobium
K1 Tantalum
K1 Group 5
K1 Oxo-chloro mixed species
K1 Hydrides
K1 Silyl
K1 Cyclopentadienyl
K1 Ciencia
K1 Química inorgánica
K1 Science
K1 Chemistry, inorganic
AB MCp* Cl,, (Cp* = $-C,Me,) reacts with LiCp (Cp = C,H,(SiMe,) (Cp’); C,H,(SiMe,), (Cp”)) and sodium amalgam, in I : I : 1molar ratio to give the paramagnetic dicyclopentadienyl niobium and tantalum(W) complexes, MCp * CpCI,, (M = Nb, Cp = Cp’ 1; Cp”2; M = Ta, Cp = Cp’ 3; Cp” 4). Reactions of 3 and 4 with l/2 equivalent of PCl, afford the diamagnetic trichlorocomplexesTaCp* CpCI,, (Cp = Cp’ 5; Cp” 6). while oxidation with dry 0, gives the diamagnetic dinuclear complexes [TaCp* CpCI,],( p-O>,(Cp = Cp’ 7; Cp” S), and with air are transformed into the corresponding oxoderivatives TaCp * CpCl(O), (Cp = Cp’ 9; Cp” 10).Treatment of compounds 3 and 4 with a slight excess of lithium aluminium hydride affords the trihydrido complexes TaCp” CpH,(Cp = Cp’ 11; Cp” 12). The trihydrido complex 12 reacts with two-electron donor ligands on heating to yield the hydrido tantalum(II1)compounds TaCp* Cp”H(L) (L = CO 13, C,H, 14, RNC 15). All the new complexes were characterized by usual IR and NMRspectroscopic methods. The crystal structures of 3 and 12 were determined by X-ray diffraction studies. Crystals of 3 are orthorhombic,space group P2,2,2,, with Z= 4 in a unit cell of dimensions a = 11.775(5) A, b = 12.821(l) A, c = 13.037(7) A. Crystals of 12 aretriclinic, space group Pi with Z = 2 in a unit cell of dimensions a = 7.384(4) A, b = 10.861(2) A, c = 16.731(3) A, LY = 75.94(2)“,p = 84.75(3)” and y = 72.57(4)‘. Both structures were solved from diffractometer data by a combination of direct and Fourier methodsand refined by full-matrix least squares fit on the basis of 4088 (3) and 4594 (12) observed reflections to R and R,. values of 0.040 and0.064 (3) and 0.022 and 0.033 (12) respectively.
PB Elsevier
SN 0022-328X
YR 1996
FD 1996
LK http://hdl.handle.net/10017/4549
UL http://hdl.handle.net/10017/4549
LA eng
NO We are grateful to DGICYT (Project PB-92-0178-C) for financial support of this research.
DS MINDS@UW
RD 23-abr-2024