In recent years several interesting reports haw appeared in the literature describing new reactions and applications of dimethyl sulfoxide. Among these was a paper by Searles and Hays5 in which they describe the formation of simple sulfoxides by heating the corresponding sulfide in dimethyl sulfoxide. When 5-hydroxy-2, 3, 4, 5-tetrahydrobenzo- [blthiepin (I) was treated under these conditions, instead of a sulfoxide 2, 3-dihydrobenzo [ ...