Crystal and Molecular Structure of Thiocarbonyl-ethoxo(tetraphenylporphyrinato)ruthenium(II), [Ru(TPP)(CS)(HOC2H5)]. A Case of Centrosymmetric–Noncentrosymmetric Ambiguity

Abstract

[Ru(TPP)(CS)(EtOH)] crystallizes in the triclinic system. Crystal data: C47H34N4ORuS, M r = 803.91, a = 10.607 (3), b = 11.308 (5), c = 17.699 (2) Å, \alpha = 77.53 (2), \beta = 73.17 (1), \gamma = 69.85 (3)°, V = 1891.6 (10) Å3, P\overline 1 (C^{1}_{i}, no. 2), Z = 2, F(000) = 824, D x = 1.410, D m = 1.39 Mg m−3 (by flotation in aqueous KI), \mu(Mo K\alpha) = 0.512 mm−1, R = 0.094, wR = 0.098, S = 2.28 for 4610 independent reflections with F o > 5\sigma(F o ). A second data set was collected using Cu K\alpha radiation. The structure was refined by standard least-squares and difference-Fourier methods in space groups P1 and P\overline 1 using both the Mo K\alpha and Cu K\alpha data sets. Both data sets favor space group P\overline 1, the Mo data giving a slightly better result than the Cu data. The two independent Ru atoms lie on the inversion centers ½,0,0 and ½,½,½ of space group P\overline 1. Consequently, the two independent molecules have crystallographically imposed \overline 1 symmetry, the CS and EtOH axial groups are disordered and the RuN4 portions of the molecules are planar. The deviations from planarity of the porphyrinato core are very small. The Ru—C—S groups are essentially linear with an average Ru—C—S bond angle of 174 (1)°. The mean Ru—C(CS) and Ru—O (Et) bond lengths are 1.92 (4) and 2.15 (3) Å, respectively.