Typically, the amine oxide is prepared from the corresponding
amine with a
peroxy acid or comparable
oxidant. The actual elimination requires just heat.
The reaction proceeds through the
Ei pathway, with an intramolecular, cyclic 5-membered
transition state.[1] Consequently, the elimination product is always
syn and rarely occurs with
6-membered rings. (
Rings with 5 or 7 or more members undergo the reaction just fine.)[6][7][8]
The reverse or retro-Cope elimination has been reported, in which an N,N-disubstituted hydroxylamine reacts with an alkene to form a tertiary N-oxide.[9][10] The reaction is a form of
hydroamination and can be extended to the use of unsubstituted hydroxylamine, in which case
oximes are produced.[11]
^Peter C. Astles; Simon V. Mortlock; Eric J. Thomas (1991). "The Cope Elimination, Sulfoxide Elimination and Related Thermal Reactions". Comprehensive Organic Synthesis. Vol. 6. pp. 1011–1039.
doi:
10.1016/B978-0-08-052349-1.00178-5.
ISBN978-0-08-052349-1.
^Amine Oxides. VIII. Medium-sized Cyclic Olefins from Amine Oxides and Quaternary Ammonium Hydroxides Arthur C. Cope, Engelbert Ciganek, Charles F. Howell, Edward E. Schweizer
J. Am. Chem. Soc., 1960, 82 (17), pp 4663–4669
doi:
10.1021/ja01502a053
^Amine Oxides. VII. The Thermal Decomposition of the N-Oxides of N-Methylazacycloalkanes Arthur C. Cope, Norman A. LeBel;
J. Am. Chem. Soc.; 1960; 82(17); 4656-4662.
doi:
10.1021/ja01502a052
^Ciganek, Engelbert; Read, John M.; Calabrese, Joseph C. (September 1995). "Reverse Cope elimination reactions. 1. Mechanism and scope". The Journal of Organic Chemistry. 60 (18): 5795–5802.
doi:
10.1021/jo00123a013.
^Ciganek, Engelbert (September 1995). "Reverse Cope elimination reactions. 2. Application to synthesis". The Journal of Organic Chemistry. 60 (18): 5803–5807.
doi:
10.1021/jo00123a014.
^Beauchemin, André M.; Moran, Joseph; Lebrun, Marie-Eve; Séguin, Catherine; Dimitrijevic, Elena; Zhang, Lili; Gorelsky, Serge I. (8 February 2008). "Intermolecular Cope-Type Hydroamination of Alkenes and Alkynes". Angewandte Chemie. 120 (8): 1432–1435.
Bibcode:
2008AngCh.120.1432B.
doi:
10.1002/ange.200703495.