Abstract
The general reactivity of several distonic radical cations (1a-11a) has been studied in solution. Hydrogen abstraction, bimolecular alkene addition and cyclization reactions of these radicals have been studied. Absolute rate constants for cyclization of the systems 6a and 7a have been measured by LFP and the rate of H-atom transfer from n-Bu3SnH has been measured by a competition study of 6a. To explore the reactive nature of these radicals Hammett and computational studies were performed. A series of p-substituted radicals 8a to 11a was involved in a competition experiment and the value for the rate constants of the cyclization process for each system was obtained. On the other hand, we present here a possible explanation of the unexpected reactivity of the systems 1a and 2a to undergo bimolecular addition to olefins, based on gas phase studies of cation p- interaction.
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References
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