Temperature Dependence of the Radical Addition to Alkenes

Abstract

In addition reactions of primary n‐hexyl, secondary cyclohexyl and tertiary butyl radicals to the alkene pair fumarodinitrile/methyl α‐chloroacrylate, the selectivities and the differences of the selectivities decrease with increasing temperature. An isoselective relationship is found with an isoselective temperature of about 280°C. Below this temperature, the frontier molecular orbital theory can be applied to explain the substituent effects on the selectivities. The previously observed breakdown of the reactivity‐selectivity principle for radical addition reactions to alkenes is, therefore, not a temperature effect.