Gallium iodide

For the preparation of subvalent gallium iodide, a simpler sonochemical synthesis based on papers of M. L. H. Green has been established (see IVB) Schnepf, A. Doriat, C. Mollhausen, E. Schnockel, H. Chem. Commun. 1997, 2111. 

Fel2[g] IRON DIIODIDE (GAS) 695 Gal3 GALLIUM IODIDE 738... 

The solid-state structure of bis(2,6-diphenylphenyl)gallium iodide, (2,6-Ph2C6H3)2GaI, displays the gallium atom in a somewhat distorted trigonal planar environment (C-Ga-C 134.3(3)°). The Ga-I bond distance of 2.550(1) A is unremarkable (Figure 4). 

Gallium iodide is prepared by Klemm and Tilk s method in the apparatus shown in Fig. 249. Metallic Ga is placed in the center section of the tube and the stoichiometric quantity of I2 in the right side flask. After evacuation and sealing at a, 13 is sublimed... 

Another example illustrating a different type of disorder is displayed in Figure 10.42. The reaction of the imininm salt [Me2N=CH2]Cl with gallium iodide, Gal , led to the dimeric [Mc2NCH2GaX2]2 (X = Cl, I) [37], The compound was crystallized, and some halogen positions were found to be occupied exclusively by... 

Fig. 10.7. High pressure mercury doped metal halide (lead-gallium-iodide additives) UV lamp, type HPM 17, Phillips [2346].

The chalcogenide bromides and chlorides may be prepared by the reaction of the halide with the respective chalcogenide in a sealed ampoule. A mixture of gallium metal and chalcogen may be used, instead of the chalcogenide. The chalcogenide iodides are S3mthesized directly from the elements. The exact preparative conditions are listed in Table XVIII 160,165). 

Ultrasonic treatment of a mixture of elemental gallium and iodine in toluene yields a light green insoluble product described as gallium(I) iodide [36], However, it now seems to be dear, as a result of several experimental observations, that a mixture of subiodides of gallium is actually formed. Nevertheless, the green powder behaves like Gal in many reactions and has also been employed for the synthesis of tetrahedral tetragallium dusters [Eq. (2)] [37, 38]. 

The effect of metal promoter species on the rate of carbonylation of [Ir(CO)2l3Me] was tested. Neutral ruthenium iodocarbonyl complexes such as [Ru(CO)3l2]2> [Ru(CO)4l2] or [Ru(CO)2l2]n were found to give substantial rate enhancements (by factors of 15-20 for a Ru Ir ratio of 1 13 at 93 °C, PhCl). Indium and gallium triiodides and zinc diiodide had comparable promotional effects. By contrast, addition of anionic ruthenium(II) species [Ru(CO)3I3] or [Ru(CO)2I4]2 did not lead to any appreciable promotion or inhibition. This behaviour indicates that the ability to accept an iodide ligand is a key property of the promoter. Indeed, it has been demonstrated that an iodide ligand can be transferred from [ Ir(C0)2l3Me] to neutral ruthenium or indium species [73,74],... 

Adolph Wurtz, 1817—1884. Professor of chemistry at the ficole de Medecine in Pans. Discoverer of methyl and ethyl amines and the synthesis of hydrocarbons from alkyl iodides and sodium. He studied the oxidation products of the glycols and the homologs of lactic acid The proof of the elementary nature of gallium was demonstrated in his laboratory by Lecoq de Boisbaudran. 

The formation of molecular complexes between aluminum trihalides and pyridine or alkylpyridines has been the subject of systematic studies.35,36 Calorimetric data yield bond dissociation energies D(X3Al—py) of 323, 308 and 264 kJ mol-1 for X = C1, Br and I, respectively, and this same order is found for alkylpyridine adducts, although the A1—N bond is weakened in the case of lutidine by the effects of steric hindrance. For gallium halides the values of D(X3M—py) are smaller 248, 237 and 195 kJ mol-1 for chloride, bromide and iodide adducts, respectively. 

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