Aryloxy Radicals from Diaryloxydiazirines:  α-Cleavage of Diaryloxycarbenes or Excited Diazirines?

Abstract

The synthesis of diaryloxydiazirines, precursors to diaryloxycarbenes, is described. Thermolyses of the diazirines afford anticipated carbene products, but photolyses afford both carbenes and aryloxy radicals by alpha-scission. UV spectra of the carbenes and radicals are observed. [reaction: see text]

Arylmethyl Radicals from Arylmethoxybromodiazirines

“…The formation of radical products ArCH 3 (Table ) requires photolysis of the diazirines, and we suggest that the diazirines' excited states ( 4* ) are the key intermediates. Recently, we reported that photolyses of diaryloxydiazirines 9 produced aryloxy radicals 10 via α-scission of the diazirines' excited states 9* ; thermolyses of 9 , however, gave only products expected from diaryloxycarbenes 11 (dimers, O−H insertion products) . We suggest that a related scenario accounts for the present findings; cf.…”

Chlorofluorocarbene: First UV Observation of a Dihalocarbene in Solution

“…N -Methanesulfonyloxy- O -phenylisourea ( 7 ) was oxidized to phenoxychlorodiazirine ( 8 ) by NaOCl in methanol. The diazirine, purified by flash chromatography, was obtained in 84% yield .…”

Syntheses and characterization of bis(trifluoromethyl)phosphino naphthalenes and acenaphthenes

“…1 H and 13 C NMR of 16 were in very good agreement with literature values. 23 16 was further characterized by ES MS, including exact mass determination. Although 16 has been reported in the literature earlier, 23 the single crystal X-ray structure has not been reported previously and is therefore attached as supplementary material.…”