Based on pulse radiolysis of aqueous solutions of two salicylic acid derivatives including ethyl salicylate and benzylsalicylate the transient absorption spectra and the rate constants of hydroxyl radical with salicyl...Based on pulse radiolysis of aqueous solutions of two salicylic acid derivatives including ethyl salicylate and benzylsalicylate the transient absorption spectra and the rate constants of hydroxyl radical with salicylic acid derivatives were determined for the first time. The results indicated that ethyl salicylate and benzylsalicylate have efficient activities to scavenge hydroxyl radical.展开更多
3-Acetyl-4-hydroxyl coumarin was synthesized by acetylation and acyl chlorination of salicylic acid followed by the cyclocondensation of acetacetic ester. Its condensation with each of three （aldehydes）, N,N-dimethy...3-Acetyl-4-hydroxyl coumarin was synthesized by acetylation and acyl chlorination of salicylic acid followed by the cyclocondensation of acetacetic ester. Its condensation with each of three （aldehydes）, N,N-dimethy-4-aminobenzaldehyde, N,N-di（4-methyphenyl）-4-aminobenzaldehyde and （N,N-）diphenyl-4-aminobenzaldehyde affords three 4-hydroxyl coumarin derivatives, i.e., 3\[（para-（dimethyamino））-cinnhyl\]-4-（hydroxyl） coumarin\1\], 3{\[para-di（4-methyphenyl）amino\]-cinnhyl}-4-（hydroxyl） coumarin\2\], and （3\[（para-）diphenylamino）-cinnhyl\]-4-hydroxyl coumarin\3\]. The three derivatives have high extinction （coefficients） in UV-vis absorption, which were 5.25×104 L/（mol·cm）, 3.39×104 L/（mol·cm）, and 3.24×104 L/（mol·cm）, respectively, and intensive luminescence in both the THF solution and solid state. Derivatives TM1 and TM2 emit intensive orange red luminescence with the same absorption peak at （500 nm） and the identical small Stoke shift of 85 nm in the emission spectra in THF. The photoluminescence peaks of the three derivatives in solid state are at 705, 643, and 660 nm, （respectively）. Derivative TM3 displays intensive red luminescence with the peak at 486 nm and a large Stoke shift of 152 nm in the emission spectrum in THF, which makes it a novel red luminescent material that may be used in OLEDs.展开更多
基金Project supported by the National Natural Science Foundation of China （No. 30100035） and the Natural Science Foundation of Fujian （No. C0510029）.
文摘Based on pulse radiolysis of aqueous solutions of two salicylic acid derivatives including ethyl salicylate and benzylsalicylate the transient absorption spectra and the rate constants of hydroxyl radical with salicylic acid derivatives were determined for the first time. The results indicated that ethyl salicylate and benzylsalicylate have efficient activities to scavenge hydroxyl radical.
文摘3-Acetyl-4-hydroxyl coumarin was synthesized by acetylation and acyl chlorination of salicylic acid followed by the cyclocondensation of acetacetic ester. Its condensation with each of three （aldehydes）, N,N-dimethy-4-aminobenzaldehyde, N,N-di（4-methyphenyl）-4-aminobenzaldehyde and （N,N-）diphenyl-4-aminobenzaldehyde affords three 4-hydroxyl coumarin derivatives, i.e., 3\[（para-（dimethyamino））-cinnhyl\]-4-（hydroxyl） coumarin\1\], 3{\[para-di（4-methyphenyl）amino\]-cinnhyl}-4-（hydroxyl） coumarin\2\], and （3\[（para-）diphenylamino）-cinnhyl\]-4-hydroxyl coumarin\3\]. The three derivatives have high extinction （coefficients） in UV-vis absorption, which were 5.25×104 L/（mol·cm）, 3.39×104 L/（mol·cm）, and 3.24×104 L/（mol·cm）, respectively, and intensive luminescence in both the THF solution and solid state. Derivatives TM1 and TM2 emit intensive orange red luminescence with the same absorption peak at （500 nm） and the identical small Stoke shift of 85 nm in the emission spectra in THF. The photoluminescence peaks of the three derivatives in solid state are at 705, 643, and 660 nm, （respectively）. Derivative TM3 displays intensive red luminescence with the peak at 486 nm and a large Stoke shift of 152 nm in the emission spectrum in THF, which makes it a novel red luminescent material that may be used in OLEDs.
