title: Synthesis, photoisomerization properties and thermal bleaching kinetics of pyrazolones containing 3-cyanobenzal.
abstract: Through the design of molecules and the modification of structures, ten novel pyrazolone derivatives containing 3-cyanobenzal have been synthesized. They are 1-phenyl-3-methyl-4-(3-cyanobenzal)-5-hydroxypyrazole thiosemicarbazone (1)/4-methyl-3-thiosemicarbazone (2)/4-ethyl-3-thiosemicarbazone (3)/4-phenyl-3-thiosemicarbazone (4)/4-phenylsemicarbazone (5) and 1,3-diphenyl-4-(3-cyanobenzal)-5-hydroxypyrazole thiosemicarbazone (6)/4-methyl-3-thiosemicarbazone (7)/4-ethyl-3-thiosemicarbazone (8)/4-phenyl-3-thiosemicarbazone (9)/4-phenylsemicarbazone (10), in which seven compounds (1, 2, 3, 6, 7, 8 and 10) have photoisomerization behaviors. Their structures, photoisomerization properties, and first-order kinetics were investigated. The results show that the compounds 2, 3, 7 and 8 exhibit irreversible photoisomerization behaviors, the other three compounds have reversible photoisomerization behaviors under 365nm light irradiation and heat. But only 1,3-diphenyl-4-(3-cyanobenzal)-5-hydroxypyrazole 4-phenylsemicarbazone (10) exhibits good photochromic properties and fatigue resistance. Moreover, effects of various temperatures on the thermal bleaching reaction for 10 and substituent groups on the photochromic phenomenon are discussed.
authors.affiliation: Key Laboratory of Material and Technology for Clean Energy, Ministry of Education, Institute of Applied Chemistry, Xinjiang University, Urumqi 830046, Xinjiang, China.
authors.forename: Caiming
authors.initials: C
authors.lastname: Deng
authors.affiliation: Key Laboratory of Material and Technology for Clean Energy, Ministry of Education, Institute of Applied Chemistry, Xinjiang University, Urumqi 830046, Xinjiang, China.
authors.forename: Samat
authors.initials: S
authors.lastname: Abdurehman
authors.affiliation: Key Laboratory of Material and Technology for Clean Energy, Ministry of Education, Institute of Applied Chemistry, Xinjiang University, Urumqi 830046, Xinjiang, China; State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012, China. Electronic address: liulang@xju.edu.cn.
authors.forename: Lang
authors.initials: L
authors.lastname: Liu
authors.affiliation: Key Laboratory of Material and Technology for Clean Energy, Ministry of Education, Institute of Applied Chemistry, Xinjiang University, Urumqi 830046, Xinjiang, China.
authors.forename: Dongling
authors.initials: D
authors.lastname: Wu
authors.affiliation: Key Laboratory of Material and Technology for Clean Energy, Ministry of Education, Institute of Applied Chemistry, Xinjiang University, Urumqi 830046, Xinjiang, China.
authors.forename: Dianzeng
authors.initials: D
authors.lastname: Jia
authors.affiliation: Key Laboratory of Material and Technology for Clean Energy, Ministry of Education, Institute of Applied Chemistry, Xinjiang University, Urumqi 830046, Xinjiang, China.
authors.forename: Rong
authors.initials: R
authors.lastname: Zhou
keywords: Photochromism; Photoisomerization; Pyrazolone; Thermal bleaching reactions