REACTIONS OF ALLYL RADICALS WITH OLEFINS

Abstract
A study has been made of the mechanisms of the reactions of allyl radicals, produced thermally from diallyl, with various hydrocarbons in the temperature range 460–506 °C. The allyl radical is capable of abstracting hydrogen from certain hydrocarbons and of adding to olefinic double bonds at these temperatures. The rates of formation of the principal products in the reactions between allyl and 1-butene, propylene, and ethylene are linearly related to the square root of the diallyl concentration. Mechanisms are proposed to account for the reaction products formed. In addition to reacting readily with olefins the allyl radical is observed to sensitize the decomposition of n-butane at 506 °C. The implications of the present results with respect to inhibition in pyrolysis of hydrocarbons are discussed briefly.