Conformational Effects in Free-Radical Hydrogen Abstraction from Medium-Ring Cycloalkanes
The case of free-radical hydrogen abstraction from cycloalkanes containing from 5 to 12 carbon atoms is compared with the reactivity of open-chain methylene groups. Activation energies for abstraction from open-chain positions are generally larger than those for all the cycloalkanes studied except cyclohexane. The results are discussed in terms of the release or aggravation of conformational strain upon forming the sp² radical center and, for the C(5)-C(12) compounds, of the inaccessibility of the C-H bonds toward attack. A recent proposal that the relative ease of forming primary, secondary, and tertiary free radicals is predominately steric in origin is discussed.
Chemistry and Geology
Journal of Organic Chemistry
Bunce, N.J. , & Hadley, M. (1974). Conformational effects in free-radical hydrogen abstraction from medium-ring cycloalkanes. Journal of Organic Chemistry, 39(15), 2271-2276. https://doi.org/10.1021/jo00929a032
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Copyright © 1974 American Chemical Society.