Semnan University Press Applied Chemistry Today 2981-2437 10 36 2015 09 23 Synthesis and Characterization of Azospiropyran Photochromic Dyes Based Para Nitro Aniline Synthesis and Characterization of Azospiropyran Photochromic Dyes Based Para Nitro Aniline 67 78 2808 10.22075/chem.2018.2637. FA Journal Article 2015 12 24 nitro-derived of azospiroptran has been synthesized by the reaction of  Fischer's base with 5-((4-nitrophenyl)diazenyl) 2-hydroxy  benzaldehyde. 5-((4-nitrophenyl)diazenyl) 2-hydroxy  benzaldehyde was obtained from the diazocoupling reaction of para nitro aniline with 2-hydroxy  benzaldehyde.With reduction NO2 group another-derived of azospiropyran was obtained. These compounds were characterized by IR and 1H,13C-NMR spectral studies. Investigating their photochromic properties   showed an increasing rate of coloration reaction in the present of substitution NH2. nitro-derived of azospiroptran has been synthesized by the reaction of  Fischer's base with 5-((4-nitrophenyl)diazenyl) 2-hydroxy  benzaldehyde. 5-((4-nitrophenyl)diazenyl) 2-hydroxy  benzaldehyde was obtained from the diazocoupling reaction of para nitro aniline with 2-hydroxy  benzaldehyde.With reduction NO2 group another-derived of azospiropyran was obtained. These compounds were characterized by IR and 1H,13C-NMR spectral studies. Investigating their photochromic properties   showed an increasing rate of coloration reaction in the present of substitution NH2. https://chemistry.semnan.ac.ir/article_2808_d0010a6f34908640a4a6da2389772a78.pdf