Nucleophile-Assisted Cleavage of Benzyltrialkylsilane Cation

20 ns) unless trace amounts of water, which acts as an efficient nucleophile, are .... diffusional separation, ksep, competes efficiently with return ...
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J. Am. Chem. Soc. 1997, 119, 1876-1883

Nucleophile-Assisted Cleavage of Benzyltrialkylsilane Cation Radicals Kevin P. Dockery,† Joseph P. Dinnocenzo,*,† Samir Farid,*,‡ Joshua L. Goodman,*,† Ian R. Gould,*,‡ and William P. Todd*,§ Contribution from the Center for Photoinduced Charge Transfer, UniVersity of Rochester, Rochester, New York 14627-0219, Department of Chemistry, UniVersity of Rochester, Rochester, New York 14627-0216, Research Laboratories, Eastman Kodak Company, Rochester, New York 14650-2109, and Department of Chemistry, State UniVersity of New York at Brockport, Brockport, New York 14480 ReceiVed September 11, 1996X

Abstract: The cation radicals of benzyltrialkylsilanes have been generated using photoinduced electron transfer and characterized using transient absorption spectroscopy. Absolute rate constants for nucleophile-assisted C-Si bond cleavage have been determined, for different nucleophiles in different solvents and with different substituents on the phenyl ring. The short lifetime (