622-62-8Relevant academic research and scientific papers
Phosphination of Phenol Derivatives and Applications to Divergent Synthesis of Phosphine Ligands
Li, Chenchen,Zhang, Kezhuo,Zhang, Minghao,Zhang, Wu,Zhao, Wanxiang
supporting information, p. 8766 - 8771 (2021/11/20)
We describe a general and efficient protocol for the synthesis of organophosphine compounds from phenols and phosphines (R2PH) via a metal-free C-O bond cleavage and C-P bond formation process. This approach exhibits broad substrate scope and excellent functional group tolerance. The synthetic utilities of this protocol were demonstrated by the synthesis of chiral ligands via the various transformations of cyano groups and their applications in asymmetric catalysis.
Hollow, mesoporous, eutectic Zn1?xMgxO nano-spheres as solid acid-base catalysts for the highly regio-selectiveO-methylation of 1,2-diphenols
Liu, Jie,Ma, Xuebing,Wang, Xuri,Xie, Guangxin,Yin, Zuyong,Zhang, Jianing
, p. 7454 - 7466 (2021/11/23)
The highly regio-selectiveO-methylation of catechol with dimethyl carbonate (DMC), catalyzed by a solid acid-base catalyst, is an environmentally friendly chemical process for industrial production of guaiacol. However, a guaiacol yield below 84% and high reaction temperature above 280 °C limit its industrial application. Here, hollow, mesoporous Zn1?xMgxO nano-spheres with a eutectic structure, denoted as Zn1?xMgxO HMNSs (x= 0.012-0.089), are facilely fabricatedviathe calcination of Mg2+/Zn2+ion-adsorbing carbon spheres at 500 °C in air. In theO-methylation of catechol with DMC at 180 °C, Zn1?xMgxO HMNSs (x= 0.052) afford guaiacol in 95.5% yield with a complete catechol conversion. Furthermore, 89.0-95.3% mono-ether yields with high 1,2-diphenol conversions (94.5-100%) are also obtained for the other 1,2-diphenols bearing -CH3and -Br groups. Moreover, a plausible mechanism for highly selectiveO-methylation of catechol with DMC is proposed, in which the single-site activation and double-site activation of phenolic hydroxyls by the basic oxygen of Mg-O afford guaiacol and veratrole, respectively.
Mustard Carbonate Analogues as Sustainable Reagents for the Aminoalkylation of Phenols
Annatelli, Mattia,Trapasso, Giacomo,Salaris, Claudio,Salata, Cristiano,Castellano, Sabrina,Aricò, Fabio
supporting information, p. 3459 - 3464 (2021/05/24)
N,N-dialkyl ethylamine moiety can be found in numerous scaffolds of macromolecules, catalysts, and especially pharmaceuticals. Common synthetic procedures for its incorporation in a substrate relies on the use of a nitrogen mustard gas or on multistep syntheses featuring chlorine hazardous/toxic chemistry. Reported herein is a one-pot synthetic approach for the easy introduction of aminoalkyl chain into different phenolic substrates through dialkyl carbonate (β-aminocarbonate) chemistry. This new direct alcohol substitution avoids the use of chlorine chemistry, and it is efficient on numerous pharmacophore scaffolds with good to quantitative yield. The cytotoxicity via MTT of the β-aminocarbonate, key intermediate of this synthetic approach, was also evaluated and compared with its alcohol precursor.
Synthetic method 4 - alkoxyphenol compounds
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Paragraph 0049-0051, (2021/09/29)
The invention discloses a synthetic method of 4 - alkoxyphenol compounds, and belongs to the field of organic chemical synthesis. The method is as follows: An aryl alkyl ether compound is added to the sealing tube. The catalyst dimerization acetic acid rhodium and the oxidizing agent iodobenzene diethyl ester are added, a solvent trifluoroacetic anhydride is added, and the 4 -alkoxyphenol compound is prepared by heating reaction. To the invention, high regioselectivity direct hydroxylation of the aryl alkyl ether compound is realized, the application range of the substrate is wide, the yield is high, the activity after amplification reaction does not significantly decay, and higher yield is still obtained. The utility model has good practicability and industrial application prospect.
Para -Selective hydroxylation of alkyl aryl ethers
Zhu, Runqing,Sun, Qianqian,Li, Jing,Li, Luohao,Gao, Qinghe,Wang, Yakun,Fang, Lizhen
supporting information, p. 13190 - 13193 (2021/12/16)
para-Selective hydroxylation of alkyl aryl ethers is established, which proceeds with a ruthenium(ii) catalyst, hypervalent iodine(iii) and trifluoroacetic anhydride via a radical mechanism. This protocol tolerates a wide scope of substrates and provides a facile and efficient method for preparing clinical drugs monobenzone and pramocaine on a gram scale.
Light assisted O-alkylation of phenols to ethers using layered double oxides catalyst under green and mild conditions
Wang, Ruiyi,Wang, Xiaoyu,Zheng, Zhanfeng
, (2020/07/03)
O-alkylation of phenols with dialkyl carbonates to ethers over layered double oxides (LDOs) catalyst under light irradiation is described. A base additive is not required when using the longer-chain diethyl carbonate as an alkylating agent owing to the sufficient basicity provided by LDOs. The synergism of substrate phenols molecules absorbing light to reach the first excited states with acid–base pairs of catalyst enhanced the interaction of reactant molecules with the surface of LDOs, simultaneously accelerating the cleavage of phenolic hydroxyl groups. A variety of phenols are tolerated in this system. This work reports a simple and environmentally benign catalytic process for the dehydrogenation of phenolic hydroxyl groups.
Efficient dealkylation of aryl alkyl ethers catalyzed by Cu2O
Liu, Lingxian,Li, Zengguang,Chen, Changjun,Li, Huanrong,Xu, Lijin,Yu, Zhiyong
supporting information, p. 2447 - 2453 (2018/04/11)
An efficient protocol for dealkylation of aryl alkyl ethers under the catalysis of inexpensive and easily reusable Cu2O has been described. The phenol products were obtained in high yields, and a range of functional groups were well tolerated. The choice of solvent is critical to the catalysis, and CH3OH proved to be the optimal choice. Mechanistic investigations showed that this reaction possibly proceeds via a single-electron transfer (SET) process.
Metal-Free Electrocatalytic Aerobic Hydroxylation of Arylboronic Acids
Luo, Jian,Hu, Bo,Sam, Alyssa,Liu, T. Leo
supporting information, p. 361 - 364 (2018/01/28)
Hydroxylation of arylboronic acids to aryl alcohols was realized by a scalable electrocatalytic method. The present electrochemical hydroxylation employs low-cost methyl viologen as an organic cathodic electrocatalyst and involves O2 as a green and sustainable reactant. The electrochemical kinetic studies shown here can be a powerful tool to gain rich mechanistic and kinetic information and thus an in-depth understanding of the electrocatalytic mechanism.
Au-Pd alloy nanoparticles supported on layered double hydroxide for heterogeneously catalyzed aerobic oxidative dehydrogenation of cyclohexanols and cyclohexanones to phenols
Jin, Xiongjie,Taniguchi, Kento,Yamaguchi, Kazuya,Mizuno, Noritaka
, p. 5371 - 5383 (2016/07/29)
Phenol, an important industrial chemical, is widely produced using the well-developed cumene process. However, demand for the development of a novel alternative method for synthesizing phenol from benzene has been increasing. Herein, we report a novel system for the synthesis of phenols through aerobic oxidative dehydrogenation of cyclohexanols and cyclohexanones, including ketone-alcohol (KA) oil, catalyzed by Mg-Al-layered double hydroxide (LDH)-supported Au-Pd alloy nanoparticles (Au-Pd/LDH). Alloying of Au and Pd and basicity of LDH are key factors in achieving the present transformation. Although monometallic Au/LDH, Pd/LDH, and their physical mixture showed almost no catalytic activity, Au-Pd/LDH exhibited markedly high catalytic activity for the dehydrogenative phenol production. Mechanistic studies showed that β-H elimination from Pd-enolate species is accelerated by Au species, likely via electronic ligand effects. Moreover, the effect of supports was critical; despite the high catalytic performance of Au-Pd/LDH, Au-Pd bimetallic nanoparticles supported on Al2O3, TiO2, MgO, and CeO2 were ineffective. Thus, the basicity of LDH plays a deterministic role in the present dehydrogenation possibly through its assistance in the deprotonation steps. The synthetic scope of the Au-Pd/LDH-catalyzed system was very broad; various substituted cyclohexanols and cyclohexanones were efficiently converted into the corresponding phenols, and N-substituted anilines were synthesized from cyclohexanones and amines. In addition, the observed catalysis was truly heterogeneous, and Au-Pd/LDH could be reused without substantial loss of its high performance. The present transformation is scalable, utilizes O2 in air as the terminal oxidant, and generates water as the only by-product, highlighting the potential practical utility and environmentally benign nature of the present transformation. Dehydrogenative aromatization of cyclohexanols proceeds through (1) oxidation of cyclohexanols to cyclohexanones; (2) dehydrogenation of cyclohexanones to cyclohexenones; and (3) disproportionation of cyclohexenones to afford the desired phenols. In the present Au-Pd/LDH-catalyzed transformation, the oxidation of the Pd-H species is included in the rate-determining step.
REGIOREGULAR COPOLYMERS AND METHODS FOR MAKING SAME
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Paragraph 0032, (2015/04/15)
Methods for producing regioregular poly(aryl ethynyl)-poly(aryl vinyl) and monomers for preparing the regioregular poly(aryl ethynyl)-poly(aryl vinyl) polymers are described herein. Regioregular poly(aryl ethynyl)-poly(aryl vinyl) are useful for electronics, among other things.
