Collection of Czechoslovak Chemical Communications - digital archive 

Abstract

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.