ic700895r_si_003.cif (164.99 kB)
Preparation, Characterization, and Structural Systematics of Diphosphane and Diarsane Complexes of Gallium(III) Halides
dataset
posted on 2007-08-20, 00:00 authored by Fei Cheng, Andrew L. Hector, William Levason, Gillian Reid, Michael Webster, Wenjian ZhangThe diphosphane o-C6H4(PMe2)2 reacts with GaX3 (X = Cl, Br, or I) in a 1:1 molar ratio in dry toluene to give
trans-[GaX2{o-C6H4(PMe2)2}2][GaX4], the cations of which contain the first examples of six-coordinate gallium in a
phosphane complex. The use of a 1:2 ligand/GaCl3 ratio produced [GaCl2{o-C6H4(PMe2)2}][GaCl4], containing a
pseudotetrahedral cation, and similar pseudotetrahedral [GaX2{o-C6H4(PPh2)2}][GaX4] complexes are the only products
isolated with the bulkier o-C6H4(PPh2)2. On the other hand, Et2P(CH2)2PEt2, which has a flexible aliphatic backbone,
formed [(X3Ga)2{μ-Et2P(CH2)2PEt2}], in which the ligand bridges two pseudotetrahedral gallium centers. The diarsane,
o-C6H4(AsMe2)2, formed [GaX2{o-C6H4(AsMe2)2}][GaX4], also containing pseudotetrahedral cations, and in marked
contrast to the diphosphane analogue, no six-coordinate complexes form; a very rare example where these two
much studied ligands behave differently towards a common metal acceptor. The complexes [(I3Ga)2{μ-Ph2As(CH2)2AsPh2}] and [GaX3(AsMe3)] are also described. The X-ray structures of trans-[GaX2{o-C6H4(PMe2)2}2][GaX4]
(X = Cl, Br or I), [GaCl2{o-C6H4(PPh2)2}][GaCl4], [GaX2{o-C6H4(AsMe2)2}][GaX4] (X = Cl or I), [(I3Ga)2{μ-Ph2As(CH2)2AsPh2}], and [GaX3(AsMe3)] (X = Cl, Br or I) are reported, and the structural trends are discussed. The
solution behavior of the complexes has been explored using a combination of 31P{1H} and 71Ga NMR spectroscopy.
