Tris(trimethylsilyl)silane (TTMSS)-derived radical reactivity toward alkenes: a combined quantum mechanical and laser flash photolysis study
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Updated: Jul 13, 2026

Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization
Published on: November 29, 2018
Jacques Lalevée1, Xavier Allonas, Jean Pierre Fouassier
1Department of Photochemistry, Ecole Nationale Supérieure de Chimie de Mulhouse, 3 rue Alfred Werner, 68093 Mulhouse Cedex, France. j.lalevee@uha.fr
Abstract:
The reactivity of the tris(trimethylsilyl)silane (TTMSS)-derived radical is studied through an approach combining laser flash photolysis and quantum mechanical calculations. The results obtained for TTMSS are compared both to a classical silyl radical derived from triethylsilane and to a previously studied carbon-centered structure. Different worthwhile results are obtained: (i) the addition and hydrogen abstraction rate constants are directly measured, (ii) the high reactivity and the low selectivity of TTMSS toward the addition to alkenes are perfectly explained by antagonist polar and enthalpy effects, (iii) efficient hydrogen abstraction reactions from antioxidants such as vitamin E are observed, and (iv) TTMSS is seen to also act as an efficient initiator for the polymerization of an acrylate monomer.
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