The crystal and molecular structure of tricarbonyl(η-methoxytropylium)chromium tetrafluoroborate

Abstract

The structure of tricarbonyl(η-methoxytropylium)chromium tetrafluoroborate has been determined by single-crystal X-ray analysis. The salt crystallises in the triclinic space group P 1 with lattice constants a 740.3(2), b 956.7(3), c 1038.4(2) pm; α 89.10(2), β 73.32(2), γ 74.31(3)°; Z = 2. The final R index for 2914 observed reflections (F ≥ 4σ) is 0.045. The cation contains an approximately planar seven-membered ring symmetrically bonded to a Cr(CO) 3 group. The C(1)O(Me) distance (133.8 pm) is intermediate between usual single- and double-bond values.