Gallium bromide compounds

Triethylgallium monoetherate, Et3Ga-(Et20), the first reported organometaiiic compound of gallium, was isolated from reaction of ethylmagnesium bromide with gallium bromide in 1932 (equation 1). ... 

In contrast to the non-trivial routes for the syntheses of pure aluminum(I) or gallium(I) subhalides, indium(I) chloride or bromide can simply be prepared by melting mixtures of elemental indium and indium trihalides [39]. When these in-dium(I) halides were treated with bulky alkyllithium compounds, deep violet orga-noelement indium dusters (13-18) were obtained [Eq. (3)] [40, 41]. 

Gallium(III) bromide is a hygroscopic, white solid which sublimes readily and melts at 122.5° to a covalent, dimeric liquid. The solid is ionic and its electrical conductivity at the melting point is twenty-three times that of the liquid.5 The vapor pressure of the liquid at T°K is given by the equation log p(mm.) = 8.554 — 3129/T and the heat of dissociation of the dimer in the gas phase is 18.5 kcal./mol.3 At 125° the liquid has the following properties 5,6 density, 3.1076 dynamic viscosity, 2.780 c.p. surface tension, 34.8 dynes/cm. and specific conductivity, 7.2 X 10-7 ohm-1 cm.-1 Gallium(III) bromide readily hydrolyzes in water and forms addition compounds with ligands such as ammonia, pyridine, and phosphorus oxychloride. 

Allylgallium and propargylgallium compounds can be prepared by the direct reaction of the corresponding bromides or iodides with gallium metal.402,403Gallium enolates are also prepared from a-halo carbonyl compounds with gallium.404... 

Chemical shifts and coupling constants have been determined in for example cyclopropyl magnesium bromide and the compounds formed with gallium, silicon, mercury, tin and lead. A complete analysis of the metal satellite spectra of tetracyclop-ropyl lead and tin and dicyclopropyl mercury has been presented ... 

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