A Caltech Library Service

Evidence for hydrogen abstraction by classical radicals in the norbornenyl-nortricyclyl system

Halgren, Thomas A. and Firkins, John L. and Fujimoto, T. A. and Suzukawa, H. H. and Roberts, John D. (1971) Evidence for hydrogen abstraction by classical radicals in the norbornenyl-nortricyclyl system. Proceedings of the National Academy of Sciences of the United States of America, 68 (12). pp. 3216-3218. ISSN 0027-8424. doi:10.1073/pnas.68.12.3216.

See Usage Policy.


Use this Persistent URL to link to this item:


Studies of product compositions and deuterium-label rearrangements at various concentrations of tri-n-butyltin hydride in the reductions of exo- and endo-5-bromonorbornene and 2-bromonortricyclene to mixtures of norbornene and nortricyclene lead to three main conclusions: (i) at least two radical intermediates contribute to product formation; (ii) each intermediate yields predominantly (80% or more) one product; and (iii) nortricyclene is predominantly derived from a symmetrical intermediate. This constitutes strong evidence for hydrogen abstraction by classical (i.e., single-product) norbornenyl and nortricyclyl radicals. It is argued that the norbornenyl-nortricyclyl system is exceptionally well suited for the generation of a nonclassical (dual-product) radical; hence, the existence of a nonclassical radical in any other system is rather unlikely.

Item Type:Article
Related URLs:
URLURL TypeDescription
Additional Information:© 1971 by the National Academy of Sciences. Contributed by John D. Roberts, September 24, 1971. This work was supported by the National Science Foundation. Contribution no. 4336 from the Gates and Crellin Laboratories of Chemistry.
Subject Keywords:free radical rearrangement; symmetrical intermediates; mechanism
Issue or Number:12
Record Number:CaltechAUTHORS:HALpnas71
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:7734
Deposited By: Tony Diaz
Deposited On:31 Jul 2007
Last Modified:08 Nov 2021 20:45

Repository Staff Only: item control page