-x + a
- *-xa+xa +
a
J . Am. Chem. SOC.,Vol. 114, No. 7 , 1992 2337
Reaction between Anions and Halogenated Methanes
per mole or more. An exception to this general trend was noted, however, in the RET reactions of perfluorinated compounds, including SF6 and C7FI4,where low reaction efficiencies were observed even for reaction systems of moderate exothermicity, up to 20 kcal m01-I.~ Considering the fundamental importance of electron-transfer processes, it its noteworthy that little attention has been given, to date, to the nature of electron-transfer reactions between molecular anions of the type A-, which are formed by the REC mechanism (reaction l), and neutral compounds of the type RX, which react with thermalized electrons by the DEC mechanism (reaction 2). It is therefore unknown which, if any, of the following mechanisms might be operative in such reactions. A-
+
-
RX
A-
A
+ RX-•
+ RX
-*
