η6-Chromiumtricarbonyl complexes of stilbene and 4,4'-dimethoxystilbene: slipping off the ligands enables cis-trans isomerization

Article abstract of DOI:10.1016/0022-328X(93)83110-H

η⁶-Chromiumtricarbonyl complexes of stilbene and 4,4'-dimethoxystilbene (both in the cis form as ligands) were prepared.The complexes are stable as dry solids, but disintegrate during exposure at 25 deg C in argon, with liberation of the ligands.They are returned as a mixture of cis-trans isomers.The conversion of cis-trans types observed depends not on the spontaneous isomerization of a ligand in a complex, but on the interaction between the slipping ligand and chromium sesquioxide - the product of the transformation of the Cr(CO)3 fragment.