Gallium trihalides

Gallium tribromide, 72 356 Gallium trichloride, 72 356 Gallium trihalides, 72 356, 357-358 Gallium triiodide, 72 356 Gallopamil, 5 121-122 molecular formula and structure, 5 119t Galvanic corrosion, 7 804-806 as failure mechanism, 26 983 in industrial water treatment,... 

Accounts of gallium which include coordination chemistry are those of Greenwood,429 Sheka et a/.,430 and Wade and Banister.1 Early work on the adducts of gallium trihalides with Lewis bases was documented in 1963,4 and this area was thoroughly reviewed by Pidcock in 1972.431 Other aspects of gallium coordination chemistry were examined by Tuck.431 Stability constants have been tabulated for a number of Ga3+ complexes.7,8... 

Being powerful acceptors, the gallium trihalides react with donor molecules L to form the adducts GaX3-L, and in some instances GaX3-2L, with a coordinate bond from the group V or VI ligand, which are treated in earlier sections. 

Pyridine readily forms stable coordination compounds. Thus, boron, aluminum and gallium trihalides react at 0°C in an inert solvent to give 1 1 adducts (cf. 85). Steric factors are important, and a-substituents decrease the ease of reaction. This is illustrated by the heats of reaction of pyridine, 2-methylpyridine and 2,6-dimethylpyridine with boron trifluoride which are 101.3, 94.1 and 73.2 kJ mol-1, respectively. The marked decrease in exothermicity here should be contrasted with the small steric requirement of the proton as shown by the pA., values of substituted pyridines (see Section 3.2.1.3.4). 

Diorgano tellurium dihalides form complexes with iodine and interhalogen compounds organic compounds with N, P, O, S, and Se donor atoms boron, aluminum, and gallium trihalides antimony pentachloride and mercury(II) halides. 

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