Reactions of Tricyclo[4.1.0.02,7]heptane and 1-Methyltricyclo[4.1.0.02,7]heptane with 2-Bromoethanesulfonyl Bromide

2-Bromoethanesulfonyl bromide reacts with tricyclo[4.1.0.0(2,7)]heptane and 1-methyltricyclo[4.1.0.0(2,7)]heptane according to a radical mechanism to give products of bothantiandsynaddition across the C-1-C(7)central bicyclobutane bond having a norpinane (bicyclo[3.1.1]heptane) structure. Treatment of the adducts with triethylamine leads to the formation of vinyl sulfones as a result of 1,2-dehydrobromination, and their reaction with sodium methoxide involves 1,2- and 1,3-dehydrobromination and nucleophilic addition, depending on the substrate structure and reactant ratio.