2-(4-Diethoxymethylphenyl)-6-(4-nitrophenyl)-4-phenyl-1,3-diazabicyclo[3.1.0]hex-3-ene

Abstract

The photochromic compound was obtained from 4-diethoxymethyl-benzaldehyde and trans-2-benzoyl-3-(4-nitrophenyl)aziridine via a three component reaction. The structure of this compound was characterized by elemental analysis, 1H-NMR, 13C-NMR and UV-Visible spectral data

2-(5-Chloro-3-methyl-1-phenyl-1H-pyrazol-4-yl)-6-(4-nitrophen­yl)-4-phenyl-1,3-diazabicyclo[3.1.0]hex-3-ene

“…Similar to the recently published synthesis [31,32], to a magnetically stirred solution of trans-2-benzoyl-3-(4-nitrophenyl)aziridine 1 (0.268 g, 1 mmol) and 5-chloro-3-methyl-1-phenyl-1H-pyrazole-4-carbaldehyde 3 (0.221 g, 1 mmol) in 7 mL of absolute ethanol was added NH 4 OAc (0.78 g, 10 mmol) at room temperature. The mixture was stirred for 48 h. The reaction mixture was filtered, washed with absolute ethanol, dried under reduced pressure, and the resulting solid was recovered, purified by silica gel column chromatography using ethyl acetate/hexane (1:5, v/v) as the eluent, and recrystallized from absolute ethanol (10 mL) to give the target compound 7a as pale beige colorless solid that changed to the deep orange (7b).…”

N-(4-(6-(4-nitrophenyl)-4-phenyl-1,3-diazabicyclo[3.1.0]hex-3-ene-2-yl)phenyl)acetamide

“…As expected, with increased irradiation time, intensity of the absorption band in the visible region is gradually increased, which states that the ring opening reaction occurs. These spectral changes showed that 4a exhibit photochromic behavior, similar to known triaryl-1,3-diazabicyclo[3.1.0]hex-3-enes [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24]. Also, an isosbestic point at 270 nm showed the presence of two species 4a and 4b.…”

“…The 1 H-NMR spectrum of purified product showed signals belonging to one of the isomers. Based on chemical shifts of the H-2, H-5, and H-6 protons and compared them with those obtained by previously reported in the literature [19][20][21][22][23][24] suggests that endo-isomer of 4 is formed. Also, 13 C-NMR spectrum is in good agreement with the title compound.…”

“…All the other aromatic protons were observed as multiplets in the region δ 7.56-7.51 ppm, integrating for six protons. It can be mentioned that this reaction led to exo-and endo-isomers with orientation of p-acetamidophenyl ring in C-2 position [6][7][8][9][10][11][12][13][14][15][16][19][20][21][22][23][24]. The 1 H-NMR spectrum of purified product showed signals belonging to one of the isomers.…”

“…to the colored azomethine ylide form (open ring) [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25]. The closed-ring and open-ring forms of bicyclic aziridines exhibited absorption spectra in solution state.…”