Resonance Stabilization of Free Radicals

This propagation reaction is facilitated by increasing resonance stabilization of the newly formed free radical. The resonance stabilization of free radicals of the type CH2CHR increases with increasing conjugation between the substituent R and the unpaired electron. In agreement with this, it has been found that the resonance stabilization of free radicals from substituted olefins, CH2=CHR, decreases in the order of the substituents, R,... 

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