A photochemical rearrangement of nitro-olefins

Investigation of photoreaction for 2-nitrobenzofuran and its 3-methyl derivative

“…2-Nitrobenzofuran 1a selectively underwent nitro-nitrite rearrangement identical to that of the photoreactions of 2-nitrofuran derivatives [19][20] or nitro-olefins [21][22][23]. Moreover, dimeric photoproducts 2f and 2g were generated in the photoreaction of 3-methyl-2-nitrobenzofuran 2a.…”

“…Moreover, irradiation of 3-methyl-2-nitrofuran caused rearrangement occurred at 5-position which produced 5-hydroxyimino-3-metylfuran-2 (5H)-one [20]. These photorearrangements are similar to those of nitro-olefins [21][22][23]. In this study, irradiation experiments of 2-nitrobenzofuran derivatives were conducted to investigate the photochemistry of nitro-substituted aromatic heterocycles.…”

“…While photosubstitution and photoredox reactions were well investigated [1][2][3][4][5][6][7][8][9][10][11][12], photodissociation and nitro-nitrite rearrangement reactions have not been completely elucidated [11][12][13][14][15][16][17][18][19][20][21][22][23][24]. This is due to the fact that nitronitrite rearrangements and photodissociation reactions have low reaction efficiencies, which makes it difficult to observe any of the short-lived reaction intermediates.…”

Simultaneous determination of β-methyl-β-nitrostyrolene and its related substances by PS-DVB chromatographic column and structural analysis of its photo-isomerization product

“…For the purposes of discussion, we started our analysis with MNS whose NMR signals could be assigned from the data reported in the literature. 19 Thus, in 1 H NMR of the mixture, the singlets at 2.44-2.46 and 8.01-8.1 ppm were attributed to the methyl H and double-bond H on MNS, while the singlets at 2.34-2.35 and 6.46-6.47 ppm were attributed to the methyl H and doublebond H on the photo-isomeride of MNS. The multiplet at 7.3-7.47 ppm was due to the aromatic group on MNS and its photo-isomeride.…”

“…But the boiling point of peak-3 was lower than MNS, therefore peak-3 was not the double-bond isomeride of MNS. The literature 18,19 showed that photo-isomerization of MNS was apt to generate nitrous acid ester, and the boiling point of nitrous acid ester was lower than nitro compounds. For example, the boiling point of ethyl nitrite was 17.2 C which was much lower than nitroethane whose boiling point was 114 C. By inference, the photo-isomeride of MNS was a-methyl-styrolene nitrite whose proposed structure is shown in Fig.…”