17764-59-9Relevant academic research and scientific papers
An investigation of 1:1 adducts of gallium trihalides with triarylphosphines by solid-state 69/71Ga and 31P NMR spectroscopy
Chen, Fu,Ma, Guibin,Bernard, Guy M.,Wasylishen, Roderick E.,Cavell, Ronald G.,McDonald, Robert,Ferguson, Michael J.
supporting information, p. 2826 - 2838 (2013/03/14)
Several 1:1 adducts of gallium trihalides with triarylphosphines, X 3Ga(PR3) (X=Cl, Br, and I; PR3=triarylphosphine ligand), were investigated by using solid-state 69/71Ga and 31P NMR spectroscopy at different magnetic-field strengths. The 69/71Ga nuclear quadrupolar coupling parameters, as well as the gallium and phosphorus magnetic shielding tensors, were determined. The magnitude of the 71Ga quadrupolar coupling constants (C Q(71Ga)) range from approximately 0.9 to 11.0 MHz. The spans of the gallium magnetic shielding tensors for these complexes, δ11-δ33, range from approximately 30 to 380 ppm; those determined for phosphorus range from 10 to 40 ppm. For any given phosphine ligand, the gallium nuclei are most shielded for X=I and least shielded for X=Cl, a trend previously observed for InIII-phosphine complexes. This experimental trend, attributed to spin-orbit effects of the halogen ligands, is reproduced by DFT calculations. The signs of C Q(69/71Ga) for some of the adducts were determined from the analysis of the 31P NMR spectra acquired with magic angle spinning (MAS). The 1J(69/71Ga,31P) and ΔJ(69/71Ga, 31P) values, as well as their signs, were also determined; values of 1J(71Ga,31P) range from approximately 380 to 1590 Hz. Values of 1J( 69/71Ga,31P) and ΔJ(69/71Ga, 31P) calculated by using DFT have comparable magnitudes and generally reproduce experimental trends. Both the Fermi-contact and spin-dipolar Fermi-contact mechanisms make important contributions to the 1J( 69/71Ga,31P) tensors. The 31P NMR spectra of several adducts in solution, obtained as a function of temperature, are contrasted with those obtained in the solid state. Finally, to complement the analysis of NMR spectra for these adducts, single-crystal X-ray diffraction data for Br3Ga[P(p-Anis)3] and I3Ga[P(p-Anis) 3] were obtained.
Gallium(III) halide complexes with phosphines, arsines and phosphine oxides - a comparative study
Cheng, Fei,Codgbrook, Hannah L.,Hector, Andrew L.,Levason, William,Reid, Gillian,Webster, Michael,Zhang, Wenjian
, p. 4147 - 4155 (2008/10/09)
The phosphine oxide complexes [GaX3(Me3PO)] and [(GaX3)2{μ-o-C6H4(CH2P(O)Ph2)2}] have been prepared and characterised by microanalysis, IR and multinuclear NMR (1H, 13C{1H}, 31P{1H} and 71Ga) spectroscopy. The structures of [GaCl3(Me3PO)], [(GaBr3)2{μ-o-C6H4(CH2P(O)Ph2)2}] and of the ionic product [GaI2(Me3PO)2][GaI4] have been determined and show that the Lewis acidity of the gallium halides towards phosphinoyl ligands diminishes as the halogen becomes heavier. The [GaX3(Ph3E)] (X = Cl, Br or I; E = P or As) and [(GaX3)2{μ-o-C6H4(CH2PPh2)2}] (X = Br or I) have been prepared and their structural and spectroscopic properties compared with those of the phosphinoyl complexes. The results, and competitive solution NMR studies, show that Ga(III) binds the hard R3PO in preference to the softer phosphine or arsine ligands. Hydrolysis of gallium(III) phosphines is shown to lead to [R3PH][GaX4], but in contrast to some other p-block halides, GaX3 do not promote air-oxidation of R3P to R3PO.
Spectroscopic and crystallographic studies of phosphino adducts of gallium(III) iodide
Brown, Martyn A.,Castro, Jesus A.,Tuck, Dennis G.
, p. 333 - 341 (2007/10/03)
The solid state structures of the compounds GaI3·PPh3 and Ga2I6·dppe (dppe = 1,2-bis(diphenylphosphino)ethane) have been determined. For the former, in which the GaI3P core has C3v symmetry, the structure is trigonal, with a = 14.961 (2) A, c = 16.509(3) A, V = 3199.5(4) A3, Z = 6, space group R3. In Ga2I6·dppe, the ligand bridges two GaI3P centres; the structure is monoclinic, a = 10.196(7) A, b = 15.363(1) A, c = 23.027(9) A, β = 98.735(4)°, V = 3565.1(3.2) A3, Z = 4, space group P21/n. The use of 31P NMR spectroscopy shows that GaI3·PPh3 is slightly dissociated in nonaqueous solution, and the effect of adding Ph3P or I- has been investigated. Similar studies with Ga2I6·dppe are also reported. In each system, four-coordination at gallium is dominant; an equally important factor is the dimerization of uncomplexed GaI3 to Ga2I6 in these solutions.
