7-Azabicyclo[2.2.1]heptadienes in electrophilic chalcogenation reactions

Reactions of electrophilic chalcogenation (sulfenylation and selenenylation) of 7-azabicyclo[2.2.1]heptadiene derivatives with electron-withdrawing substituents at the nitrogen atom and the double bond were found to proceed trans-stereospecifically with the formation of 1,2-addition products, resulting from the exo-attack by the electrophile. In the case of 2-tosyl-7-azanorbornadiene, the reaction is regiospecific: the electrophilic species exclusively adds to the carbon atom at position 6. A comparative analysis of the behavior of dimethyl bicyclo-[2.2.1]heptadiene-2,3-dicarboxylate and its 7-aza analogs in the AdE reactions was carried out.