Hydrido-complexes of rhenium-containing tertiary phosphines

Abstract

Hydrido-complexes of Rhenium-containing Tertiary Phosphines de 1969, page 1963, Title should read as: Hydrido-complexes of Rhenium which contain Tertiary Phosphines. The preparation, characterisation, and some properties of hydrido-rhenium complexes containing tertiary phosphines are described. The complexes [ReX,(PR,),] [X = halogen, X, = OCI, or O(OR')CI,: R = alkyl or aryl groups], with lithium aluminium hydride, give three classes of hydride complexes of the general formulae [ReH,-(PR3),], [{ReHZ(PR3),},]( X -= 7) and [ReH,(PR,),] according to the actual phosphine used and the experimental conditions. The interconversions of the three classes of hydride complexes, their reactions with some neutral ligands and with acids, and their hydrogen deuterium exchange reactions with alcohols, hydrogen, and benzene are described. 1.r.. u.v., and n.m.r. spectral data and dipole moment data are recorded. These hydridorhenium complexes differ in a number of ways from their formally similar analogues of the Group Vlll metals.

Mono‐ and Dinuclear Rhenium Polyhydride Complexes Bearing the Chelating Ligand 1,2‐Bis(dicyclohexylphosphanyloxy)ethane

“…In the 31 P{ 1 H} NMR spectrum, the broad signal at δ ϭ 144.7 ppm sharpens when the temperature is raised and between 273 and 293 K is progressively replaced by a new singlet at δ ϭ 151.3 ppm (Figure 3). This signal remains unaltered when the sample is maintained at 293 K for 24 h. Heating of a solution of the heptahydride 1 to reflux in toluene for 24 h [14] resulted in the precipitation of a yellow solid with analytical and spectroscopic data in accordance with the formulation [Re 2 H 8 (dcype) 2 ] (3). The 31 P{ 1 H} NMR spectrum of a solution of 3 in CD 2 Cl 2 exhibits a single singlet at δ ϭ 162.4 ppm showing the magnetic equivalence of the four P nuclei, while the 1 H NMR spectrum shows an eight-proton quintuplet at δ ϭ Ϫ7.37 ppm ( 2 J PH ϭ 9 Hz).…”

“…Its IR spectrum shows two medium bands at 1933 and 1956 cm Ϫ1 which are attributable to ν(ReϪH) vibrations. [14] At room temperature, the 1 H NMR spectrum of 1 in C 6 D 6 shows the hydride resonance as a seven-proton triplet at δ ϭ Ϫ6.55 ppm (J PH ϭ 17 Hz), while the 31 P{ 1 H} NMR spectrum displays a singlet at δ ϭ 157.0 ppm which becomes an octuplet when an off-resonance experiment is performed [J PH(residual) ϭ 15 Hz]. These results confirm the number of hydride ions coordinated to the rhenium atom and show the magnetic equivalence of the two phosphorus atoms in the bidentate ligand.…”

Preparation and characterization of chloro- and polyhydride complexes of rhenium: Variable-temperature NMR spectroscopy and protonation studies

“…Its IR spectrum shows two medium-strong bands at 1915 and 1971 cm À1 that are attributable to Re-H stretching vibrations [15]. Like the homologous complexes of 1,2-bis(diphenylphosphanyloxy)ethane [6] and 1,2-bis(dicyclohexylphosphanyloxy)ethane [7] (hereinafter L [6] and L [7] , respectively), compound 4 is converted into a dinuclear compound, [Re 2 H 8 L 2 ], when dissolved in CHCl 3 , CH 2 Cl 2 , benzene Table 1 Bond lengths (Å ) and angles (°) in 2 or toluene.…”

Low-temperature neutron diffraction study of [ReH5(PPh i Pr2)2(SiHPh2)2] and low-temperature X-ray diffraction study of [ReH5(PCyp3)2(SiH2Ph)2]

“…Thermal reactions of the [ReH7(PR3)2] complexes, in which H2 dissociates from the molecule, and the resulting transient species reacts with an appropriate substrate, are well established (Zeiher, DeWit & Caulton, 1984). We have found (Dix & Spencer, 1988) that under appropriate conditions, such reactions with silanes (Luo, Baudry, Boydell, Charpin, Neirlich, Ephritikhine & Crabtree, 1990) Chatt & Coffey (1969).…”