Structural characterization of charge transfer complexes of the Nickel(IV) bis-(3,1,2-dicarbollyl) sandwich compound

摘要

The charge transfer complexes of commo-Ni(3,1,2,-C2B9H11)(2) (1) with naphthalene(1 . C10H8), pyrene(1 . C16H10) and N,N-dimethylaniline (1 . C6H5NMe2) were structurally characterized by X-ray diffraction studies. 1 . C10H8 crystallized in the orthorhombic space group Pnma with a = 9.825(7), b = 13.257(10) and c = 18.114(14) Angstrom, V = 2359 Angstrom(3) and Z = 4. Data were collected to a maximum 2 theta = 115 degrees, giving 1426 unique reflections. The final discrepancy index was R = 0.077, R-w = 0.090 for 919 independent reflections with I > 2 sigma(I). 1 . C16H10 was crystallized in the orthorhombic space group P2(1)2(1)2(1) with a = 6.967(1), b = 14.804(2) and c = 26.200(4) Angstrom, V = 2702 Angstrom(3) and Z = 4. Data were collected to a maximum of 2 theta = 50 degrees, giving 2751 unique refections. The final discrepancy index was R = 0.075, R-w = 0.094 for 1812 independent refections with I > 3 sigma(I). 1 . C6H5NMe2 crystallized in the orthorhombic space group Pn2(1)a (standard setting Pna2(1)) with a = 9.476(2), b = 13.160(2) and c = 18.389(4) Angstrom, V = 2304 Angstrom(3), and Z = 4. Data were collected to a maximum of 2 theta = 45 degrees, giving 1581 unique reflections. The final discrepancy index was R = 0.055, R-w = 0.070 for 1152 independent reflections with I = 3 sigma(I). Crystallographic data, in combination with molecular orbital calculations, demonstrate that in each case the nickelacarborane acceptor orients itself with respect to the donor molecule to maximize orbital overlap, thereby facilitating charge transfer. [References: 17]