The effect of the phenyl substituent on the nitrogen inversion barrier in a 2-phenyloxaziridine

The photochemistry of the N-oxide function

“…26 Likewise, oxygen migration from one nitrogen atom to another nitrogen atom in aromatic azoxy derivatives has been observed and rationalized as occurring via reversible cyclization to an oxadiaziridine. 28 Correspondingly, photochemical racemization of the chiral oxaziridine 14 takes place through a photochemical equilibrium with the nitrone 15…”

A computational investigation on the photochemistry of the popular spin‐trap agent N‐tert‐butyl‐α‐phenylnitrone (PBN) and thermal isomerization pathways of its photoproduct oxaziridine

“…Photo-irradiation studies on the open chain N-alkyl-α-phenylnitrones were first extensively studied by Emmons 16 which was followed by the work of Splitter [17][18][19] and Boyd groups. [20][21][22][23][24][25][26] These include the above-mentioned PBN system along with its derivatives.…”

“…Photo-isomerization studies on α,Ndiphenylnitrone was first reported by Shinzawa and Tanaka. 27 Some other significant studies on similar nitrones or their photoproducts include the determination of inversion barrier of the chiral nitrogen, epimerization/racemization 19,25,26,28,29 of oxaziridines and oxaziridine to nitrone reverse conversion 24,[30][31][32][33][34] reaction. A comparative data on the nitrogen inversion for different types of substituted oxaziridines can be found in the review article by Yoon et al 35 In the last decade, photo-rearrangement studies on some analogous alkyl-aryl nitrones have been reported by Zhang et al 36 and Chaudhuri et al 37 However, the exact reaction paths involved in these reactions were not clearly understood and predictions were made to explain the observations in some of these studies.…”