Indium(III) halide-3,5-di-tert-butyl- o-benzosemiquinone systems

• Published in: Inorganica Chimica Acta Vol. 225; no. 1; pp. 207 - 213
• Main Authors: Annan, Theodore A., Brown, Martyn A., El-Hadad, Ahmed, McGarvey, Bruce R., Ozarowski, Andrzej, Tuck, Dennis G.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.10.1994
• Subjects: Benzosemiquinone complexes; Crystal structures; Electron transfer; Halide complexes; Indium complexes; Indium complexes; Electron transfer; Crystal structures; Halide complexes; Benzosemiquinone complexes
• ISSN: 0020-1693; 1873-3255
• DOI: 10.1016/0020-1693(94)04049-4

The reaction of InX 3 (X  Cl, Br, I) with 2 mol of Na +TBSQ · − (TBSQ · − =3,5-di- t-butyl- o-benzosemiquinonate anion) yields solutions of the diradicals InX(TBSQ) 2, whose EPR spectra have been recorded. Addition of pyridine or γ-picoline (L) to such solutions produces adducts of the 3,5-di- t-butylcatecholate-indium(III) halide, of the type In(TBC)XL n . The mechanism of these reactions, and of the related ligand replacement and disproportionation equilibria, is discussed in terms of internal one-electron transfer processes. The compound In(TBC)(pic) 2·DMF has been the subject of an X-ray crystallographic study. The substance forms monoclinic crystals, space group P2 1/ n with a=12.992(5), b=13.923(4), c=18.491(4) Å, β=98.82(2) o, Z=4, R=0.053 for 3244 unique reflections. The molecule is dimeric, with a central In 2O 2 ring, involving six-coordinate indium(III).