Electrophilic phenylsulfenylation of syn-7-tert-butoxy-2-phenylsulfonyl- bicyclo[2.2.1] hepta-2,5-diene with phenylsulfenyl chloride yielded a mixture of three simple adducts, two of which were derived by the endo face attack of the phenylsulfenyl cation. In the analogous reaction with the anti derivative, only one adduct with the exo phenylsulfanyl group at the nearer carbon was obtained. This product was derived by the attack of the phenylsulfenyl cation from the exo face followed by the endo attack of a chloride anion at the carbon opposite to the phenylsulfonyl group. The similar reaction of 7-tert-butoxybicyclo[2.2.1]hepta-2,5-diene itself underwent no Wager-Meerwein-type rearrangement or transannular reaction, and simple adducts were formed in good combined yield. The combined yield of the products reacted at the syn double bond was ca. 80%.