New Reactions of Furoxans: Formation of Alkynes and Cyclobutaphenanthrenes.

Abstract Diarylfuroxans were found to give diaryacetylenes upon irradiation at 254 nm. Cyclobutaphenanthrenes were also obtained when reaction was carried out in the presence of alkenes. The acetylenic derivative is supposed to arise by loss of (NO) 2 from a diazete-N,N-dioxide. Unimolecular and collision activated dissociation studies by tandem mass spectrometry also support the loss of (NO) 2 from diarylfuroxans molecular ions.