Copper(I), copper(II), and heterovalent copper(I,II) complexes with 1,10-phenanthroline and the closo-decaborate anion

The reactions proceeding in air between Cu-I/Cu-II and phen and influence of the closo-decaborate anion on the reaction path are studied. In the absence of [B10H10](2), a rapid redox reaction between CuCl and phen yields [Cu-2(II)(phen)(4)(mu-CO3)]Cl-2 (2). The [B10H10](2) anion produces a decelerating effect on the redox reaction. It stabilizes the +1 oxidation state of copper and coordinates two metal atoms by apical faces to form [Cu-2(I)(phen)(2)[B10H10]] (3). Heating of the reaction mixture results in [Cu-I(phen)(2)](2)[B10H10] (4) and [Cu-I(phen)(2)](2)[Cu-II(phen)(3)][B10H10](2) (5) indicating that a part of copper atoms is oxidized and the borohydride ligand is replaced by phen molecules in the inner sphere of the metal. Compounds [Cu-2(II)(phen)(4)(mu-CO3)][B10H10] (1) and [Cu(phen)(2)][B10H10] (6) are prepared starting from Cu-II-phen complexes. Compounds 1-6 are identified by IR spectroscopy, elemental analysis, and X-ray diffraction. (C) 2015 Elsevier B.V. All rights reserved.