Co-ordination compounds of indium. Part XI. The stepwise one-electron reduction of some neutral indium(III) complexes

The complex InL3(L = 3-hydroxy-2-methyl-4-pyronato-anion) has been prepared, and its n.m.r., i.r. and Raman spectra compared with those of the parent ligand. Polarographic reduction of this complex, and of In(trop)3(trop = tropolonato-anion) takes place in successive one-electron steps, as in the case of complexes of indium with bidentate sulphur-donor ligands. One-electron polarographic reduction of In (acac)3(acac = acetylacetonato-anion) and In(oxine)3(oxine = quinolin-8-olato-anion) has also been observed, and may be a general property of complexes of indium(III) with bidentate chelating ligands.