579-75-9Relevant articles and documents
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Gilman et al.
, (1945)
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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.
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.
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.].