607-85-2Relevant articles and documents
Electronically Induced Proton Transfer Reactions in Salicylic Acid Esters and Salicyloyl Chloride
Catalan, F.,Toribio, J.,Amat, F.,Acuna, A. U.
, p. 817 - 822 (1983)
The multiple fluorescence emission spectra, excitation spectra, and lifetime of isopropyl salicylate, tert-butyl salycilate, and salicyloyl chloride have been analyzed in the gas phase and in cyclohexane and N,N-dimethylformamide solutions.Study of the electronic emission and IR absorption spectra of both esters and methyl salicylate gives further support to the hypothesis of a ground-state equilibrium between two intramolecular H-bonded conformers.The efficiency of the excited-state proton transfer reaction was determined from fluorescence and lifetime data of the 450-nm emission and found to be ca. 40percent lower in tert-butyl than in methyl salicylate.On the other hand, the characteristic fast electronic energy relaxation of these compounds was not sensitive to the carboxyl substituent.Finally, the effect of solvent polarity on the radiationless rate was discussed in terms of the interaction between (?,?*) and (n,?*) states of the zwitterionic structures.
Enantioselective degradation of the organophosphorus insecticide isocarbophos in Cupriavidus nantongensis X1T: Characteristics, enantioselective regulation, degradation pathways, and toxicity assessment
Fang, Liancheng,Xu, Luyuan,Zhang, Nan,Shi, Qiongying,Shi, Taozhong,Ma, Xin,Wu, Xiangwei,Li, Qing X.,Hua, Rimao
, (2021)
The chiral pesticide enantiomers often show selective efficacy and non-target toxicity. In this study, the enantioselective degradation characteristics of the chiral organophosphorus insecticide isocarbophos (ICP) by Cupriavidus nantongensis X1T were investigated systematically. Strain X1T preferentially degraded the ICP R isomer (R-ICP) over the S isomer (S-ICP). The degradation rate constant of R-ICP was 42-fold greater than S-ICP, while the former is less bioactive against pest insects but more toxic to humans than the latter. The concentration ratio of S-ICP to R-ICP determines whether S-ICP can be degraded by strain X1T. S-ICP started to degrade only when the ratio (CS-ICP/CR-ICP) was greater than 62. Divalent metal cations could improve the degradation ability of strain X1T. The detected metabolites that were identified suggested a novel hydrolysis pathway, while the hydrolytic metabolites were less toxic to fish and green algae than those from P-O bond breakage. The crude enzyme degraded both R-ICP and S-ICP in a similar rate, indicating that enantioselective degradation was due to the transportation of strain X1T. The strain X1T also enantioselectively degraded the chiral organophosphorus insecticides isofenphos-methyl and profenofos. The enantioselective degradation characteristics of strain X1T make it suitable for remediation of chiral organophosphorus insecticide contaminated soil and water.
Direct Hydroxylation and Amination of Arenes via Deprotonative Cupration
Tezuka, Noriyuki,Shimojo, Kohei,Hirano, Keiichi,Komagawa, Shinsuke,Yoshida, Kengo,Wang, Chao,Miyamoto, Kazunori,Saito, Tatsuo,Takita, Ryo,Uchiyama, Masanobu
supporting information, p. 9166 - 9171 (2016/08/05)
Deprotonative directed ortho cupration of aromatic/heteroaromatic C-H bond and subsequent oxidation with t-BuOOH furnished functionalized phenols in high yields with high regio- and chemoselectivity. DFT calculations revealed that this hydroxylation reaction proceeds via a copper (I → III → I) redox mechanism. Application of this reaction to aromatic C-H amination using BnONH2 efficiently afforded the corresponding primary anilines. These reactions show broad scope and good functional group compatibility. Catalytic versions of these transformations are also demonstrated.
SO3H-functionalized Bronsted acidic ionic liquids as efficient catalysts for the synthesis of isoamyl salicylate
Tao, Duan-Jian,Wu, Jing,Wang, Zhen-Zhen,Lu, Zhang-Hui,Yang, Zhen,Chen, Xiang-Shu
, p. 1 - 7 (2014/01/06)
Six Bronsted acidic ionic liquids (BAILs) composed of [HSO 4] were prepared, characterized, and used as catalysts of low dosage in the synthesis of isoamyl salicylate. The effects of various parameters such as the kind of BAILs, temperature, catalyst loading, and molar ratio of the reactants on the conversion of salicylic acid were also examined in detail. The results suggested that the catalytic performances of BAILs were of close relevance to their Hammett acidities. The SO3H-functionalized BAILs 1-(4-sulfonic acid) butyl-3-methylimidazolium hydrogen sulfate ([BSmim][HSO 4]) and N-(4-sulfonic acid) butyl triethylammonium hydrogen sulfate ([BSEt3N][HSO4]) of strong acidities exhibited excellently catalytic activities and selectivities in the esterification of salicylic acid with isoamyl alcohol. The fully optimized geometries of [BSmim][HSO4] and [BSEt3N][HSO4] further manifest that their strong acidities are derived from the strong interactions between the anion with the sulfonic acid group. In addition, it was found that [BSmim][HSO4] could be also recovered easily and used repetitively at least six times without obvious decline in activity and quantity.
