X-Ray Crystal Structures oftrans-(Chloromethyl)bis(2,4-pentanedionato)(aqua and methanol)chromium(III) Completes. Evidence for a Trans Influence Exerted in the Carbon-Bonded Chromium(III) Complexes

The crystal and molecular structures of alkylchromium(III) complexes, trans-[Cr(CH2Cl)(acac)2(H2O)]·EtOH and trans-[Cr(CH2Cl)(acac)2(MeOH)] (acac−=2,4-pentanedionate anion, EtOH=ethanol, MeOH=methanol), have been determined by X-ray structure analyses. Both crystals are triclinic and the space group P\bar1; Z=2 with a=9.935(2), b=10.606(2), c=9.399(2) A, α=90.39(2), β=92.44(2), γ=115.54(1)° for the aqua complex, and Z=4 with a=11.402(6), b=16.780(7), c=8.543(3) A, α=98.83(3), β=102.00(4), γ=83.03(4)° for the methanol complex. Each complex has trans configuration. The carbon-bonded CH2CI group elongates specifically the Cr–O bond trans to the Cr–C bond in the aqua complex (Cr–O(H2O)=2.134(6) A) and methanol complex (Cr–O(MeOH)=2.156(6), 2.136(6) A).