| Abstract
| - A comparison between experimental and theoretical data on regioselectivity concerningthe hydroformylation of several vinyl substrates (propene, 2-methylpropene, 1-hexene, 3,3-dimethylbutene, fluoroethene, 3,3,3-trifluoropropene, vinylmethylether, allylmethylether,styrene) with unmodified rhodium catalysts is reported. Various H−Rh(CO)3-olefin complexesare examined at the B3P86/3-21G or /6-31G* level (LANL2DZ for Rh) and compared to theadducts with modified catalysts, such as HRhPH3(CO)2. The computed geometries are insatisfactory agreement with the X-ray ones. The activation energies for the alkyl rhodiumintermediate formation, computed at either level along the pathways to branched or linearaldehydes, allow one to predict the regioselectivity ratios, since they are in very goodagreement with the experimental ones evaluated for the isomeric aldehydes.
- A comparison between experimental and theoretical data of regioselectivity concerning the hydroformylation of several vinyl substrates with unmodified rhodium catalysts is reported. Various H−Rh(CO)3-olefin complexes are examined at the B3P86/3-21G or /6-31G* level (LANL2DZ for Rh) and compared to the adducts with modified catalysts. The activation energies for the alkyl rhodium intermediate formation, computed along the pathways to branched or linear aldehydes, predict the regioselectivity ratios in very good agreement with the experimental ones evaluated for the isomeric aldehydes.
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