摘要
Three new photoisomeric compounds: 1,3-diphenyl-4-benzal-5-pyrazolone 4-methylthiosemicarbazone (DPBP-MTSC), 1,3-diphenyl-4-(4′-methylbenzal)-5-pyrazolone 4-methylthiosemicarbazone (DP4MBP- MTSC), and 1,3-diphenyl-4-(4′-bromobenzal)-5-pyrazolone 4-methylthiosemicarbazone (DP4BrBP-MTSC) were synthesized by direct condensation of pyrazolones and 4-methylthiosemicarbazone. Their struc- tures were confirmed using 1H NMR, IR, elemental analyses, and X-ray crystallographic analyses. The photoisomeric properties in the solid state were studied under UV light irradiation and the photo- isomerization phenomena were interpreted by the double proton-transfer mechanism. Moreover, the effects of different substituent groups at the 4-position of the benzal in the three compounds on the photoisomeric properties were discussed.
Three new photoisomeric compounds: 1,3-diphenyl-4-benzal-5-pyrazolone 4-methylthiosemicarbazone (DPBP-MTSC), 1,3-diphenyl-4-(4′-methylbenzal)-5-pyrazolone 4-methylthiosemicarbazone (DP4MBPMTSC), and 1,3-diphenyl-4-(4′-bromobenzal)-5-pyrazolone 4-methylthiosemicarbazone (DP4BrBP-MTSC) were synthesized by direct condensation of pyrazolones and 4-methylthiosemicarbazone. Their structures were confirmed using 1H NMR, IR, elemental analyses, and X-ray crystallographic analyses. The photoisomeric properties in the solid state were studied under UV light irradiation and the photoisomerization phenomena were interpreted by the double proton-transfer mechanism. Moreover, the effects of different substituent groups at the 4-position of the benzal in the three compounds on the photoisomeric properties were discussed
基金
Supported by the National Natural Science Foundation of China (Grant No. 20462007)
University Scientific Research Program of Education Bureau, Xinji-ang Uygur Autonomous Region (XJEDU2004G01 and XJEDU2004E01)
