Journal of the Chemical Society Faraday Transactions · 1990 · 51 citations · 25 references
Natural SciencesChemistryPhysicsChemical KineticsOrganic ChemistryPhysical ChemistryChemical Kinetics ModelingChemical Reaction KineticsGas-phase Reaction KineticsKinetic ModelingReaction Mechanism ModelingReaction MechanismsGas-phase ReactionsPhotolysisPressure Dependence Of Reaction RatesPressure-dependent ReactionsRate ConstantsReaction Rate CoefficientsReaction Rate ConstantsRrkm Theory
Absolute rate constants for reactions of silylene have been determined by time-resolved measurements of its decay at room temperature, following formation by pulsed-laser photolysis of phenylsilane in the presence of various added silanes. For SiH4 and Si2H6 the rate coefficients are pressure dependent and the former reaction is successfully modelled using RRKM theory. High-pressure (or pressure-independent) rate constants (in 10–10 cm3 molecule–1 s–1) are: SiH4, ca. 4.0; Si2H6, ca. 6.5; MeSiH3, 3.66 ± 0.22; Me2SiH2, 3.31 ± 0.26; and Me3SiH, 2.47 ± 0.14. These results are compared with other determinations and the rate constants for the analogous reactions of SiMe2. A model for the insertion reaction is proposed in which the nucleophilic stage of the process plays an important role.
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