The mechanism of 1,2-addition of disilene and silene. 1. Water and alcohol addition

T. Veszprémi, M. Takahashi, B. Hajgató, M. Kira

Research output: Contribution to journalArticle

45 Citations (Scopus)

Abstract

The mechanism of 1,2-addition reactions of water, methanol, and trifluoromethanol to Si=Si, Si=C, and C=C bonds has been investigated by ab initio quantum chemical methods. Geometries and relative energies of the stationary points and all the transition states were determined using the MP2/6-311++G(d,p), B3LYP/6-311++G(d,p), and CBS-Q levels of theory. The investigated reactions can be characterized by two main thermodynamical profiles. The type in which the reagent molecule attacks a carbon atom is moderately exothermic, with a high activation barrier. The second type, in which water or alcohol attacks a silicon, is strongly exothermic, with a small activation energy. At the early stage of all the reactions, a weakly bonded initial complex is found which determines the further mechanism of the reaction. On the basis of the HOMO, LUMO, and Laplacian of electron distribution of disilene and silene, several mechanisms have been assumed, depending on the substrate (disilene, substituted disilene, silene, or ethene) and the reagent (water, methanol, or trifluoromethanol). The reaction diagrams and proposed mechanisms explain the experimentally found regioselectivity and diastereoselectivity well.

Original languageEnglish
Pages (from-to)6629-6638
Number of pages10
JournalJournal of the American Chemical Society
Volume123
Issue number27
DOIs
Publication statusPublished - 2001

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Silene
Alcohols
Methanol
Water
Regioselectivity
Addition reactions
Silicon
Carbon
Activation energy
Chemical activation
Electrons
Atoms
Molecules
Geometry
Substrates
trifluoromethanol

ASJC Scopus subject areas

  • Chemistry(all)

Cite this

The mechanism of 1,2-addition of disilene and silene. 1. Water and alcohol addition. / Veszprémi, T.; Takahashi, M.; Hajgató, B.; Kira, M.

In: Journal of the American Chemical Society, Vol. 123, No. 27, 2001, p. 6629-6638.

Research output: Contribution to journalArticle

Veszprémi, T. ; Takahashi, M. ; Hajgató, B. ; Kira, M. / The mechanism of 1,2-addition of disilene and silene. 1. Water and alcohol addition. In: Journal of the American Chemical Society. 2001 ; Vol. 123, No. 27. pp. 6629-6638.
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