Trapped Electrons in Alcohols

Salient Features of B.S.R. Spectra of Trapped Electrons in Alcohols at 77 °K 

The mechanism that is most compatible with the experimental observations is a single-stage process which can be represented formally as 

This reaction proceeds by a concerted mecbanism in wbicb tbe electron becomes localized on tbe oxygen atom of tbe hydroxyl group simultaneously with the combination of tbe hydrogen atom of that group with an a-hydrogen atom of a neighbouring molecule. 

The observed activation energy is close to those found for lattice rearrangements similar to that required for this concerted process, (Denney and Cole, 1955 Glasstone et al., 1941 McColl et al., 1959). The low pre-exponential factors are in accord with the low probability of forming the appropriate structure necessary for the reaction to occur. 

The subsequent decay of the a-hydroxyalkyl radicals by a mutual termination reaction should yield a glycol, by combination, and an aldehyde, by disproportionation. Thus, there is an interesting difference between the reaction of individual alkali metal atoms with solid alcohols at low temperatures and the corresponding reaction between alkali metals and liquid alcohols at room temperature when the major products are molecular hydrogen and alkoxide ions. 

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