Direct femtosecond observation of the transient intermediate in the α-cleavage reaction of (CH3)2CO to 2CH3+CO: Resolving the issue of concertedness
- 1 July 1995
- journal article
- research article
- Published by AIP Publishing in The Journal of Chemical Physics
- Vol. 103 (1) , 477-480
- https://doi.org/10.1063/1.469614
Abstract
When a reaction involving two equivalent bonds has sufficient energy to break both of them, it can proceed by either a concerted or a stepwise mechanism. For Norrish type‐I and other reactions, this issue has been controversial since direct time resolution of the individual C–C cleavage events was not possible. Here, for the elementary α‐cleavage of acetone, we report on the femtosecond resolution of the intermediates using mass spectrometry. The results show the nonconcertedness of the reaction, provide the times for the primary and secondary C–C breakage, and indicate the role of electronic structure (σ*, antibonding impulse) and the vibrational motions involved.Keywords
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