Amine oxide pyrolysis Cope Reaction

A. C. Cope and E. R. Trumbull, "Olefins from Amines. The Flofmann Elimination Reaction and Amine Oxide Pyrolysis," Organic Reactions 11, 317 (1960). 

Pyrolysis of Amine Oxides The Cope Elimination Reaction ... 

Cope, A. C., Trumbull, E. R. Olefins from amines the Hofmann elimination reaction and amine oxide pyrolysis. Org. React. 1960,11, 317-493. 

Pyrolysis of tertiary amine oxides (the Cope elimination reaction) also offers relatively mild reaction conditions (100-200 °C). Oxidation of the tertiary amine... 

Cope, A.C., Trumbull, E.R. (1975) Olefins from Amines The Hofmann Elimination Reaction and Amine Oxide Pyrolysis in Organic Reactions, RE Krieger Publ. Co., New York. 

However, when the temperature is increased to 120°C, the principal reaction is the elimination to olefin. The thermal decomposition of dimethyl dodecyl amine oxide at 125°C in a sealed system, as opposed to a vacuum used by Cope and others, produces 2-methyl-5-decyhsoxa2ohdine, dimethyl dodecyl amine, and olefin (23). The amine oxide oxidi2es XW-diaLkylhydroxylainine to the nitrone during the pyrolysis and is reduced to a tertiary amine in the process. 

Amines oxides. Procedures for the preparation of an aliphatic amine (4), its conversion to the amine oxide (5), and pyrolysis of this to methylenecyclohexane (6, Cope reaction) are shown in the formulation. A homogeneous solution of 0.35... 

Cope elimination reaction. Formation of an olefin and a hydroxylamine by pyrolysis of an amine oxide. 

This conclusion was supported by the observation that pyrolysis of 3-butenol has a AS of —8.8 eu, which is similar to the activation entropy values reported for pyrolysis of ethyl formate and for 3-butenoic acid, and the activation energies for all three pyrolyses are also similar (about 40 kcal/mol). Another well-known concerted syn elimination is the Cope elimination, which involves the thermal elimination of an alkene from an amine oxide (Figure 10.53). Unlike the reactions discussed above, all of which have... 

The pyrolysis of amine oxides is called Cope elimination and typically takes place at 120 °C (Scheme 6.21). The reaction is a syn periplanar elimination in which six electrons move in a five-membered ring according to a concerted, thermally induced mechanism to yield an alkene and a hydroxylamine. 

Pyrolysis of the oxide of tertiary amine 1 yields olefin 2 and hydroxylamine 3. This olefination method is known as the Cope elimination reaction.1-3... 

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