DFT Study of the Homogeneous Hydroformylation of Propene Promoted by a Heterobimetallic Pt–Sn Catalyst

• Published in: Organometallics 2011-08, Vol.30 (16), p.4257-4268
• Main Authors: Dias, Roberta P, Rocha, Willian R
• Format: Article
• Language: English
• ISSN: 0276-7333; 1520-6041
• DOI: 10.1021/om1012067

Full quantum mechanical calculations at the DFT level were carried out to study the full catalytic cycle for the hydroformylation of propene, catalyzed by the heterobimetallic catalyst trans-[HPt(PPh3)2(SnCl3)] with real triphenylphosphine ligands. All intermediates and transition states along the elementary steps of the entire catalytic cycle were located and the energies involved in the catalytic cycle calculated using the BP86 functional. The solvent effects along the entire catalytic cycle were evaluated using the polarizable continuum model. The regioselectivity of the hydroformylation is set at the olefin insertion step, with the aldehyde reductive elimination being the rate-determining step of the entire cycle, with an activation free energy of 18.1 kcal mol–1, in line with the experimental findings. The trans effect of the SnCl3 ligand seems to be pronounced only in the first step of the catalytic cycle, facilitating the insertion of the olefin into the Pt–H bond trans to it. The BP86 calculations predict a diasteroselectivity ratio of 95:5 in favor of the linear aldehyde product, which it is in excellent agreement with the experimental value.