Electron transfer, part 145 - Aqueous solutions of hypovalent gallium; reductions using gallium(I)

Solutions 0.2 mol dm(-3) in Ga-I, prepared by dissolving Ga2Cl4 in dry acet onitrile, are stable for more than seven days and may be diluted 300- to 10 00-fold with O-2-free water to give Ga-I preparations that may be handled b y conventional techniques; these Ga-I(aq) solutions readily reduce I-3(-), Br-2(aq), IrCl62-, Fe(bipy)(3)(3+) and aquacob(III)alamin (B-12a) but are i nert to Co(NH3)(5)Cl2+ and Co(NH3)(5)Br2+; reduction of HCrO4- in 2-ethyl-2 -hydroxybutanoate buffers yields the Cr-IV chelate of the buffering anion.