A Polymer Chain Compound of [Rh2II(4-Me-pf)2(O2CCMe3)2(1,4-dib)]n (4-Me-pf- = N,N′-Di-p-tolylformamidinate Anion; 1,4-dib = 1,4-Diisocyanobenzene)

The title polymer compound with chlorobenzene as crystal solvents [Rh-2(II)(4-Me-pf)(2)(O2CCMe3)(2)(1,4-dib)](n)center dot n(chlorobenzene) (4-Me-pf(-) = N,N'-di-p-tolylformamidinate; 1,4-dib = 1,4-diisocyanobenzene) was isolated and the crystal structure was determined by the single-crystal X-ray diffraction method at 150 K. It crystallizes in the triclinc space group P (1) over bar with a = 10.6491(8)angstrom, b = 12.5796(11)angstrom, c = 19.3388(15)angstrom, alpha = 85.901(5)degrees, beta = 77.146(5)degrees, gamma = 85.792(5)degrees, V = 2514.9(4) angstrom(3), D-x = 1.446 g/cm(3), and Z = 2. The R-1 [I > 2 sigma(I)] and wR(2) (all data) values are 0.0555 and 0.1563, respectively, for all 8757 independent reflections. Two Rh-II atoms are bridged by two 4-Me-pf(-) and two pivalato ligands in the cis-(2:2) fashion. The axial sites of the dinuclear core are occupied by 1,4-dib ligands with distances of Rh-C-ax = 2.129(6) and 2.129(7)angstrom to form a chain structure with alternated arrangement of cis-[Rh-2(II)(4-Me-pf)(2)(O2CCMe3)(2)] and 1,4-dib. The Rh-Rh distance is 2.4845(6)angstrom, which is longer than the observed range for those of the lantern-type dirhodium(II) complexes with formamidinato and pivalato bridges and axially coordinating nitorgen atoms, reflecting the strong donor properies of the 1,4-dib carbon atoms. The diffuse reflectance spectra and adsorption properties for N-2 were also examined.