Hydrogen abstraction from 2- and 3-methylthiophens investigated by spin trapping

Abstract

The homolytic reactivity of 2- and 3-methylthiophens towards hydrogen abstraction from the side-chain by t-butoxyl radicals has been investigated by determining the relative amount either of the coupling products of 2- and 3-thenyl radicals or of the nitroxides obtained by trapping with Bu^tNO. The conditions for the latter experiment have been explored and are discussed. Both methods showed that 2-methylthiophen is 2·2 time more reactive than the 3-isomer.