499-06-9Relevant articles and documents
Ferric ion concentration-controlled aerobic photo-oxidation of benzylic C–H bond with high selectivity and conversion
Bu, Hongzhong,Gu, Jiefan,Li, Yufeng,Ma, Hongfei,Wan, Yuting,Wu, Zheng-Guang,Zhang, Weijian,Zhou, Ying'ao,Zhu, Hongjun
, (2021/07/16)
A Fe(III)-promoted highly selective photo-oxidation of benzylic C–H bond delivering relative carbonyl products is reported. By altering the concentration of ferric salt, methylarenes can be selectively oxidized under UV irradiation to furnish aromatic aldehydes or acids, respectively. By this protocol, the oxidation of ethylarenes provides the corresponding acetophenones. The reaction is inferred to involve divergent pathways in different concentrations of catalyst for the alternative selectivity between aldehydes and aicds. The reusable catalyst, high conversion and selectivity make this oxidation a green and economic protocol for the synthesis of aromatic carbonyl compounds.
Reaction method for selectively synthesizing aromatic aldehyde or aromatic carboxylic acid
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Paragraph 0035-0036, (2020/12/05)
The invention provides a reaction method for selectively synthesizing aromatic aldehyde or aromatic carboxylic acid. Toluene aromatic hydrocarbon without substituent or with substituent on a benzene ring is used as a raw material, an inorganic salt of ferric iron is used as a catalyst, air or oxygen is used as an oxidizing agent, a mixed solution of acetonitrile and water is used as a solvent, theraw material is oxidized by adjusting the dosage of the catalyst to obtain aromatic aldehyde or aromatic carboxylic acid, and the aromatic aldehyde or aromatic carboxylic acid is irradiated by ultraviolet light for 10-16 hours. Aromatic carboxylic acid obtained under the condition that the dosage of the catalyst is 5-50% mol of aromatic hydrocarbon is used as a main product, wherein the use amount of the catalyst is 70-200% mol of aromatic hydrocarbon. The reaction method provided by the invention has the characteristics of atom economy and high selectivity, uses the metal iron salt with richearth content for catalysis, and has the advantages of mild conditions, recyclable catalyst and solvent and the like.
Cobalt-catalyzed carboxylation of aryl and vinyl chlorides with CO2
Wang, Yanwei,Jiang, Xiaomei,Wang, Baiquan
supporting information, p. 14416 - 14419 (2020/12/01)
The transition-metal-catalyzed carboxylation of aryl and vinyl chlorides with CO2 is rarely studied, and has been achieved only with a Ni catalyst or combination of palladium and photoredox. In this work, the cobalt-catalyzed carboxylation of aryl and vinyl chlorides and bromides with CO2 has been developed. These transformations proceed under mild conditions and exhibit a broad substrate scope, affording the corresponding carboxylic acids in good to high yields.
Green synthesis method of aromatic acid
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Paragraph 0048-0122; 0241-0245; 0271-0272, (2020/05/01)
The invention discloses a green synthesis method of aromatic acid. Nickel-catalyzed carbonyl insertion is carried out on aryl iodine in the presence of formate, acid anhydride, a phosphine ligand andan organic solvent by using a nickel catalyst to obtain the aromatic acid. Efficient catalytic conversion is realized by utilizing the cheap nickel catalyst, the reaction conditions are mild, and theoperation is simple.
Nickel-catalyzed carboxylation of aryl iodides with lithium formate through catalytic CO recycling
Fu, Ming-Chen,Fu, Yao,Shang, Rui,Wu, Ya-Nan
supporting information, p. 4067 - 4069 (2020/04/20)
A protocol for the Ni-catalyzed carboxylation of aryl iodides with formate has been developed with good functional group compatibility for the synthesis of a variety of aromatic carboxylic acids under mild conditions. The reaction tolerates other functionalities for cross-coupling, such as aryl bromide, aryl chloride, aryl tosylate, and aryl pinacol boronate. The reaction proceeds through a carbonylation process with in situ generated carbon monoxide in the presence of a catalytic amount of acetic anhydride and lithium formate, avoiding the use of gaseous CO. The strategy of CO recycling in catalytic amounts is critical for the success of the reaction.
Aliphatic amines modified CoO nanoparticles for catalytic oxidation of aromatic hydrocarbon with molecular oxygen
Liu, Meng,Shi, Song,Zhao, Li,Chen, Chen,Gao, Jin,Xu, Jie
, p. 1488 - 1493 (2019/09/09)
The surface modification of metal oxides using organic modifiers is a potential strategy for enhancing their catalytic performances. In this study, a hydrophobic surface amine-modified CoO catalyst with a water contact angle of 143° was fabricated. The catalyst was characterized by XRD, TGA, FT-IR, HR-TEM, and XPS. The results showed that the fabricated catalyst performed better than the hydrophilic commercial CoO nanoparticle in the process of aromatic hydrocarbon oxidation. After the amines modification, commercial CoO also became hydrophobic and improved conversion of ethylbenzene was achieved. The surface modification of CoO with amines induced the hydrophobicity property, which could serve as a reference for the design of other hydrophobic catalysts.
Efficient catalytic oxidation of methyl aromatic hydrocarbon with: N -alkyl pyridinium salts
Zhang, Qiaohong,He, Honghao,Wang, Huibin,Zhang, Zhan,Chen, Chen
, p. 38891 - 38896 (2019/12/11)
A series of N-alkyl pyridinium salts were synthesized and employed as metal-free catalyst for the selective oxidation of methyl aromatic hydrocarbon with molecular oxygen. The electronic effect of the substitutes was found to be an important factor for the catalytic performance. With the introduction of electron-donating substitute -N(CH3)2, the conversion of p-xylene and selectivity of p-toluic acid could be simultaneously increased. 1-Benzyl-4-N,N-dimethylaminopyridinium salt showed the highest catalytic activity, and 95% conversion with 84% of selectivity to p-toluic acid could be obtained for the selective oxidation of p-xylene. Several methyl aromatic hydrocarbons could all be efficiently oxidized with the reported catalyst at the absence of any metal species.
Assessing the effectiveness of oxidative approaches for the synthesis of aldehydes and ketones from oxidation of iodomethyl group
Faisal, Muhammad,Hussain, Sarwat,Haider, Azeem,Saeed, Aamer,Larik, Fayaz Ali
, p. 1053 - 1067 (2019/04/25)
Owing to excellent selectivity, high yield and stability towards over-reduction and over-oxidation, one of the impressive approaches to synthesize aldehydes and ketones is the oxidation of halomethyl groups. Numerous halomethyl oxidation-based methodologies to afford aldehydes and ketones are disclosed in the literature. Mostly, chloromethyl or bromomethyl group containing substrates have been used in the literature for performing oxidation. There are negligible data available in the literature that addresses the use of iodomethyl group containing substrates for transformation to aldehydes and ketones. In this research work, 110 reactions have been carried out to construct aldehydes and ketones from oxidation of iodomethyl group in benzylic iodides and allylic iodides using numerous well-known approaches reported in the literature. The classical approaches under observation include Sommelet oxidation, Kr?hnke oxidation, sodium periodate-mediated oxidative protocol, manganese dioxide-based oxidative approach, Kornblum oxidation and Hass–Bender oxidation. The eco-friendly approaches under observation include periodic acid-based IL protocol, periodic acid in vanadium pentoxide-mediated IL method, hydrogen peroxide in vanadium pentoxide-based approach and bismuth nitrate-promoted IL technique. In this investigation, yield, recyclability, cost-effectiveness, eco-friendliness and over-oxidation are the main parameters which are under observation. Among all these investigated techniques, periodic acid-based IL protocol, periodic acid in vanadium pentoxide-mediated IL method and hydrogen peroxide in vanadium pentoxide-based approach (aka. Chunbao oxidation protocol) were found to be highly efficient due to the following reasons: these approaches (1) provide excellent yields, (2) do not lead towards over-oxidation, (3) show good recyclability, (4) demonstrate high thermal stability and negligible flammability, and (5) require no special handling.
Nickel-catalyzed carboxylation of aryl and heteroaryl fluorosulfates using carbon dioxide
Ma, Cong,Zhao, Chuan-Qi,Xu, Xue-Tao,Li, Zhao-Ming,Wang, Xiang-Yang,Zhang, Kun,Mei, Tian-Sheng
, p. 2464 - 2467 (2019/04/10)
The development of efficient and practical methods to construct carboxylic acids using CO2 as a C1 synthon is of great importance. Nickel-catalyzed carboxylation of aryl fluorosulfates and heteroaryl fluorosulfates with CO2 is described, affording arene carboxylic acids with good to excellent yields under mild conditions. In addition, a one-pot phenol fluorosulfation/carboxylation is developed.
An efficient approach for enhancing the catalytic activity of Ni-MOF-74: Via a relay catalyst system for the selective oxidation of benzylic C-H bonds under mild conditions
Guo, Changyan,Zhang, Yonghong,Zhang, Yi,Wang, Jide
supporting information, p. 3701 - 3704 (2018/04/17)
Although nickel-based materials exhibit similar catalytic activity to palladium in organic synthesis, the selective oxidation of inert C-H bonds in the absence of other co-catalysts remains a largely unsolved challenge. This paper introduces a facile and efficient approach for enhancing the catalytic activity of Ni-MOF-74 with [bmim]Br via a relay catalysis strategy, which is excellent for the selective oxidation of benzylic C-H bonds. Notably, the catalyst recycling and scale up experiments demonstrated the practicability of the protocol. This method combines the catalytic advantages of MOFs and ionic liquids (ILs), and provides an insight into oxidation reactions by cheap and efficient Ni-based catalysts.
