The interaction of aromatic hydrocarbons with organometallic compounds of the main group elements. : IV. The preparation and structure of the novel selenide K[CH 3Se{Al(CH 3) 3} 3] · 2C 6H 6

Abstract

The crystal structure of K[CH 3Se {Al(CH 3) 3} 3] · 2C 6H 6 has been determined from single-crystal X-ray diffraction data collected by counter methods. The compound crystallizes in the triclinic space group P 1 with cell dimensions a = 17.165(7), b = 10.144(7), c = 10.156(7)Å, α = 119.26(5), β = 104.07(5), ψ = 80.51(5)°, and Dc = 1.12 gcm −3 for Z = 2. Least-squares refinement gave a final R value of 0.083 for 1967 independent observed reflections. One of the two benzene molecules in the asymmetric unit has been located by difference Fourier techniques. Because of either extreme disorder or high thermal motion, the aromatics make practically no contribution to the X-ray scattering. The selenium atom in the anion exhibits tetrahedral coordination. The Al-Se bond lengths average 2.578(5)Å, and the Se-C distance is 1.93(2)Å.