CRYSTAL AND MOLECULAR STRUCTURE OF PHENYLTRIMETHYLENEMETHANEIRON TRICARBONYL

Phenyltrimethylenemethaneiron tricarbonyl, [(CH2)2C(CHC6H6)] Fe(CO)3, crystallizes in the centrosymmetric monoclinic space group P21/a (C2; no. 14) with a = 16.322 ± 0.012 Å, b = 6.632 ± 0.005 Å, c = 12.542 ± 0.008 Å, β = 117.18 ± 0.05°, and Z = 4. Observed and calculated densities are 1.33 ±0.05 and 1.289 g cm-8, respectively. A single-crystal X-ray diffraction study has been carried out. Data complete to sin θ = 0.42 (Mo Kα radiation) were collectedwith a 0.01°-incrementing Buerger automated diffractometer, andthe structure was solved by a combination of Patterson, Fourier, and least-squares refinement procedures. All atoms (including hydrogens) have been located, t e final discrepancy index being Rp = 7.85% for the 1459 independent, nonzero reflections. The crystal is composed of molecular units of [(CH2)2C-(CHC6H6)]Fe(CO)3, separated by normal van der Waals distances. The iron atom is located directly beneath the central atom of the trimethylenemethane residue and is bonded to the four carbon atoms of this system. The carbon atom skeleton of the trimethylenemethane moiety is significantly nonplanar, the central atom being displaced (away from the iron) by 0.315 Å relative to the plane defined by the three terminal carbon atoms. The trimethylenemethane ligand and the Fe(CO)3 group adopt a mutually staggered conformation. © 1969, American Chemical Society. All rights reserved.