Author, as appears in the article.: Plessow, Philipp N.; Carbo, Jorge J.; Schaefer, Ansgar; Hofmann, Peter;
Department: Química Física i Inorgànica
URV's Author/s: Carbó Martin, Jorge Juan
Keywords: Zeta-valence quality Transition-state method Substituted cyclopropanes Regular 2-component hamiltonians Reductive elimination-reactions Palladium(ii) complexes Hydrogen-bonds Electronic-structure Copper-catalyzed cyclopropanation C-h bonds
Abstract: Platinum(0) complexes with the chelate ligand bis(di-tert-butylphosphino)methane, tBu2P-CH2-PtBu2 (dtbpm), generated in solution from appropriate precursors, are the only known transition metal species that selectively activate epoxides (oxiranes) by inserting the Pt fragment into their carbon¿carbon bond. The mechanism of this unprecedented reaction is studied theoretically using the random phase approximation. We find that the reaction is kinetically controlled and is caused by the formation of a monocoordinate (dtbpm-κ1P)Pt(0) fragment rather than a (dtbpm-κ2P)Pt(0) chelate complex. Insertion into epoxide C¿C bonds occurs without energy barrier. Conceivable competing reactions, oxirane C¿O and C¿H activation, both proceed via formation of a σ-complex, followed by small but significant barriers for insertion steps. A reversible formation of the σ-complexes would perfectly explain the observed reactivity. For an irreversible formation, we find that intramolecular rearrangement of these σ-complexes toward C¿C activation products is faster than both C¿O and C¿H activation. In principle, the same reactivity should be expected for other monocoordinated platinum(0) phosphine complexes. However, only the specific properties of dtbpm cause the subsequent, rapid, and irreversible closing of the chelate ligand yielding stable, square-planar Pt(II) C¿C activation products.
Thematic Areas: Química Physical and theoretical chemistry Organic chemistry Materiais Inorganic chemistry Engenharias ii Ciências biológicas ii Ciências agrárias i Chemistry, organic Chemistry, inorganic & nuclear Astronomia / física
licence for use: https://creativecommons.org/licenses/by/3.0/es/
Author's mail: j.carbo@urv.cat
Author identifier: 0000-0002-3945-6721
Record's date: 2024-09-07
Papper version: info:eu-repo/semantics/publishedVersion
Licence document URL: https://repositori.urv.cat/ca/proteccio-de-dades/
Papper original source: Organometallics. 34 (15): 3764-3773
APA: Plessow, Philipp N.; Carbo, Jorge J.; Schaefer, Ansgar; Hofmann, Peter; (2015). Selective Carbon–Carbon Bond Activation of Oxirane by a Bisphosphine Pt(0) Complex—A Theoretical Study. Organometallics, 34(15), 3764-3773. DOI: 10.1021/acs.organomet.5b00435
Entity: Universitat Rovira i Virgili
Journal publication year: 2015
Publication Type: Journal Publications
Repositori URV