579-75-9Relevant academic research and scientific papers
Synthesis of 9-ethoxycarbonyl-10(10aH)-oxo-5,6,7,8,8a,9-hexahydro-9,10a- anthracenecarbolactone and related compounds by manganese(III) mediated cyclization
Ohta, Shunsaku,Kajiura, Takahiro,Murai, Hiromichi,Yamashita, Masayuki,Kawasaki, Ikuo
, p. 2557 - 2560 (1999)
Novel tetracyclic lactone (5a), 9-ethoxycarbonyl-10(10aH)-oxo- 5,6,7,8,8a,9-hexahydro-9,10a-anthracenecarbolactone, was obtained in 34.8% yield by oxidative cyclization of diethyl trans-2-benzoylcyclohexylmalonate (4a) with manganese(III) acetate dihydrate in the presence of sodium acetate in acetic acid.
Kinetic Evidence for the Occurence of the Oxydianionic Tetrahedral Intermediates in the Hydrolyses of Methyl Salicylate and methyl o-Methoxybenzoate in Highly Alkaline Medium
Khan, M. Niyaz,Olagbemiro, T. O.
, p. 3695 - 3699 (1982)
The kinetics of hydrolyses of methyl salicylate and methyl o-methoxybenzoate have been studied at various hydroxide ion concentrations ranging from 0.01 to 4.40 M for methyl salicylate and from 0.005 to 0.200 M formethyl o-methoxybenzoate at 35 deg C.The observed rate constants are independent of -> within the range 0.01-0.04 M and vary according to equation kobsd = A + B-> + C->2 within the range 0.04-3.60 M for hydrolysis of methyl salicylate where A = k3k1/(k1 + k3),B = k2k4/(k-2 + k4), and C = k2k5K/(k-2 + k4).The observed rate constants for hydrolysis of methyl o-methoxybenzoate follow the equation kobsd = B1-> + C1->2 where B1 = k1'k2'/(k-1' + k2') and C1 = k1'k3'K'/(k-1' + k2').The pH-independent observed rate constants are 1E4 and 1E5 times larger than the corresponding values for water-catalyzed cleavages of methyl benzoate and methyl o-methoxybenzoate, respectively.This rate enhancement has been attributed to the probable intramolecular general-base-catalyzed neutral hydrolysis of methyl salicylate.The ratios B/B1 and C/C1 have been found to be 0.0214 and 0.0004, respectively.The apperance of C and C1 terms in the kinetic equations has been attributed to the existence of the oxydianionic tetrahedral intermediates in the reaction mechanisms.The temperature dependence of hydrolysis of methyl salicylate has also been studied at two differentOH- concentrations.The intramolecular general-base-catalyzed rate enhancement has been found to be due toa favorable ΔS*.The hydrolytic cleavage of methyl salicylate has been found to be sensitive to the ionic strenght.The probable mechanisms for hydrolyses of both esters are considered.
Mechanochemical Grignard Reactions with Gaseous CO2 and Sodium Methyl Carbonate**
Pfennig, Victoria S.,Villella, Romina C.,Nikodemus, Julia,Bolm, Carsten
supporting information, (2022/01/22)
A one-pot, three-step protocol for the preparation of Grignard reagents from organobromides in a ball mill and their subsequent reactions with gaseous carbon dioxide (CO2) or sodium methyl carbonate providing aryl and alkyl carboxylic acids in up to 82 % yield is reported. Noteworthy are the short reaction times and the significantly reduced solvent amounts [2.0 equiv. for liquid assisted grinding (LAG) conditions]. Unexpectedly, aryl bromides with methoxy substituents lead to symmetric ketones as major products.
Design, synthesis, and biological studies of novel 3-benzamidobenzoic acid derivatives as farnesoid X receptor partial agonist
Hu, Lijun,Ren, Qiang,Deng, Liming,Zhou, Zongtao,Cai, Zongyu,Wang, Bin,Li, Zheng
, (2020/12/25)
Farnesoid X receptor (FXR), a bile acid-activated nuclear receptor, regulates the metabolism of bile acid and lipids as well as maintains the stability of internal environment. FXR was considered as a therapeutic target of liver disorders, such as drug-induced liver injury, fatty liver and cholestasis. The previous reported FXR partial agonist 6 was a suitable lead compound in terms of its high potent and low molecular size, while the docking study of compound 6 suggested a large unoccupied hydrophobic pocket, which might be provided more possibility of structure-activity relationship (SAR) study. In this study, we have performed comprehensive SAR and molecular modeling studies based on lead compound 6. All of these efforts resulted in the identification of a novel series of FXR partial agonists. In this series, compound 41 revealed the best activity and strong interaction with binding pocket of FXR. Moreover, compound 41 protected mice against acetaminophen-induced hepatotoxicity by the regulation of FXR-related gene expression and improving antioxidant capacity. In summary, these results suggest that compound 41 is a promising FXR partial agonist suitable for further investigation.
Efficiency of lithium cations in hydrolysis reactions of esters in aqueous tetrahydrofuran
Harada, Yumi,Hayashi, Kazuhiko,Ichimaru, Yoshimi,Imai, Masanori,Kojima, Yuki,Maeda, Azusa,Nakayama, Kanae,Sugiura, Kirara
, p. 581 - 594 (2021/06/06)
Lithium cations were observed to accelerate the hydrolysis of esters with hydroxides (KOH, NaOH, LiOH) in a water/tetrahydrofuran (THF) two-phase system. Yields in the hydrolysis of substituted benzoates and aliphatic esters using the various hydroxides were compared, and the effects of the addition of lithium salt were examined. Moreover, it was presumed that a certain amount of LiOH was dissolved in THF by the coordination of THF with lithium cation and hydrolyzed esters even in the THF layer, as in the reaction by a phase-transfer catalyst.
Synthesis and antioxidant activities of berberine 9-: O -benzoic acid derivatives
Liu, Yanfei,Long, Shuo,Zhang, Shanshan,Tan, Yifu,Wang, Ting,Wu, Yuwei,Jiang, Ting,Liu, Xiaoqin,Peng, Dongming,Liu, Zhenbao
, p. 17611 - 17621 (2021/05/29)
Although berberine (BBR) shows antioxidant activity, its activity is limited. We synthesized 9-O-benzoic acid berberine derivatives, and their antioxidant activities were screened via ABTS, DPPH, HOSC and FRAP assays. The para-position was modified with halogen elements on the benzoic acid ring, which led to an enhanced antioxidant activity and the substituent on the ortho-position was found to be better than the meta-position. Compounds 8p, 8c, 8d, 8i, 8j, 8l, and especially 8p showed significantly higher antioxidant activities, which could be attributed to the electronic donating groups. All the berberine derivatives possessed proper lipophilicities. In conclusion, compound 8p is a promising antioxidant candidate with remarkable elevated antioxidant activity and moderate lipophilicity.
Aerobic oxidation of aldehydes to carboxylic acids catalyzed by recyclable ag/c3 n4 catalyst
Wu, Chaolong,Yao, Xiaoquan,Yu, Min,Zhou, Li,Zhu, Li
, p. 167 - 175 (2021/03/19)
The oxidation of aldehydes is an efficient methodology for the synthesis of carboxylic acids. Herein we hope to report a simple, efficient and recyclable protocol for aerobic oxidation of aldehydes to carboxylic acid by using C3N4 supported silver nanoparticles (Ag/C3N4) as a catalyst in aqueous solution under mild conditions. Under standard conditions, the corresponding carboxylic acids can be obtained in good to excellent yields. In addition, Ag/C3N4 is convenient for recovery and could be reused three times with satisfactory yields.
Photo-induced deep aerobic oxidation of alkyl aromatics
Wang, Chang-Cheng,Zhang, Guo-Xiang,Zuo, Zhi-Wei,Zeng, Rong,Zhai, Dan-Dan,Liu, Feng,Shi, Zhang-Jie
, p. 1487 - 1492 (2021/07/10)
Oxidation is a major chemical process to produce oxygenated chemicals in both nature and the chemical industry. Presently, the industrial manufacture of benzoic acids and benzene polycarboxylic acids (BPCAs) is mainly based on the deep oxidation of polyalkyl benzene, which is somewhat suffering from environmental and economical disadvantage due to the formation of ozone-depleting MeBr and corrosion hazards of production equipment. In this report, photo-induced deep aerobic oxidation of (poly)alkyl benzene to benzene (poly)carboxylic acids was developed. CeCl3 was proved to be an efficient HAT (hydrogen atom transfer) catalyst in the presence of alcohol as both hydrogen and electron shuttle. Dioxygen (O2) was found as a sole terminal oxidant. In most cases, pure products were easily isolated by simple filtration, implying large-scale implementation advantages. The reaction provides an ideal protocol to produce valuable fine chemicals from naturally abundant petroleum feedstocks. [Figure not available: see fulltext.].
Alkali-modified heterogeneous Pd-catalyzed synthesis of acids, amides and esters from aryl halides using formic acid as the CO precursor
Fapojuwo, Dele Peter,Maqunga, Nomathamsanqa Prudence,Meijboom, Reinout,Mogudi, Batsile M.,Molokoane, Pule Petrus,Onisuru, Oluwatayo Racheal,Oseghale, Charles O.
, p. 26937 - 26948 (2021/08/17)
To establish an environmentally friendly green chemical process, we minimized and resolved a significant proportion of waste and hazards associated with conventional organic acids and molecular gases, such as carbon monoxide (CO). Herein, we report a facile and milder reaction procedure, using low temperatures/pressures and shorter reaction time for the carboxyl- and carbonylation of diverse arrays of aryl halides over a newly developed cationic Lewis-acid promoted Pd/Co3O4catalyst. Furthermore, the reaction proceeded in the absence of acid co-catalysts, and anhydrides for CO release. Catalyst reusability was achievedviascalable, safer, and practical reactions that provided moderate to high yields, paving the way for developing a novel environmentally benign method for synthesizing carboxylic acids, amides, and esters.
Palladium supported on a novel ordered mesoporous polypyrrole/carbon nanocomposite as a powerful heterogeneous catalyst for the aerobic oxidation of alcohols to carboxylic acids and ketones on water
Ganji, Nasim,Karimi, Babak,Najafvand-Derikvandi, Sepideh,Vali, Hojatollah
, p. 13616 - 13631 (2020/04/24)
Preparation of an ordered mesoporous polypyrrole/carbon (PPy/OMC) composite has been described through a two-step nanocasting process using KIT-6 as a template. Characterization of the PPy/OMC nanocomposite by various analysis methods such as TEM, XRD, TGA, SEM and N2 sorption confirmed the preparation of a material with ordered mesoporous structure, uniform pore size distribution, high surface area and high stability. This nanocomposite was then used for the immobilization of palladium nanoparticles. The nanoparticles were almost uniformly distributed on the support with a narrow particle size of 20-25 nm, confirmed by various analysis methods. Performance of the Pd?PPy/OMC catalyst was evaluated in the aerobic oxidation of various primary and secondary alcohols on water as a green solvent, giving the corresponding carboxylic acids and ketones in high yields and excellent selectivity. The catalyst could also be reused for at least 10 reaction runs without losing its catalytic activity and selectivity. High catalytic efficiency of the catalyst can be attributed to a strong synergism between the PPy/OMC and that of supported Pd nanoparticles.
