 This reaction type was discovered in 1970 by Bunnett and Kim and the abbreviation SRN1 stands for substitution radical-nucleophilic unimolecular as it shares properties with an aliphatic SN1 reaction.An example of this reaction type is the Sandmeyer reaction.In this radical substitution the aryl halide 1 accepts an electron from a radical initiator forming a radical anion 2.