Collect. Czech. Chem. Commun. 1980, 45, 1940-1949

Reactivity of cycloalkenes in the radical addition reaction with ethyl cyanoacetate

Milan Hájek and Jaroslav Málek

Institute of Chemical Process Fundamentals, Czechoslovak Academy of Sciences, 165 02 Prague 6- Suchdol


The effect of ring size on the reactivity of C5 to C12 cycloalkenes in the copper(II) oxide catalysed and dibenzoyl peroxide initiated addition reaction with ethyl cyanoacetate was determined at 90°C using the method of competition reactions. cis-Cyclooctene exhibited the highest and cyclohexene as well as cis-cyclodecene the lowest reactivity. Relative reactivities of C5, C6 cis-C7 and cis-C8 cycloalkenes could be correlated with the Allinger's strain energies. In the copper(II) oxide catalysed reaction, the relative reactivities of cycloalkenes were surprisingly higher than in the dibenzoyl peroxide initiated reaction; this result is indicative of certain differences in the mechanism of the initiation and propagation steps in both systems. The radical addition of ethyl cyanoacetate to cycloalkenes represent a novel and convenient route to alkyl α-cyanocycloalkaneacetates.