Abstract
Thermal fragmentation of O-Aryl-N,N-diphenylhydroxylamines I and II were investigated. Neat heating in an atmospheric nitrogen afforded arenes, biaryl, diaryl sulfide, diphenylamine, diaryl sulfone, phenols, arenesulfonic acid, carbazole, and thianthrene. In the presence of isoquinoline as a radical trap, I gave 1-phenylisoquinoline as well as the previous products. Analogous results were obtained on heating of I in boiling tetraline, which lead to the formation of 1-hydroxytetraline, α -tetralone, and 1,1′-bitetralyl as the major products. A free-radical mechanism has been postulated to take place through the initial homolysis of N─O and S─O bonds to account for the identified products.