16766-30-6Relevant articles and documents
Semisynthetic Phenol Derivatives Obtained from Natural Phenols: Antimicrobial Activity and Molecular Properties
Pinheiro, Patrícia Fontes,Menini, Luciana Alves Parreira,Bernardes, Patrícia Campos,Saraiva, Sérgio Henriques,Carneiro, José Walkimar Mesquita,Costa, Adilson Vidal,Arruda, Társila Rodrigues,Lage, Mateus Ribeiro,Gon?alves, Patrícia Martins,Bernardes, Carolina De Oliveira,Alvarenga, Elson Santiago,Menini, Luciano
, p. 323 - 330 (2018)
Semisynthetic phenol derivatives were obtained from the natural phenols: thymol, carvacrol, eugenol, and guaiacol through catalytic oxychlorination, Williamson synthesis, and aromatic Claisen rearrangement. The compounds characterization was carried out by 1H NMR, 13C NMR, and mass spectrometry. The natural phenols and their semisynthetic derivatives were tested for their antimicrobial activity against the bacteria: Staphylococcus aureus, Escherichia coli, Listeria innocua, Pseudomonas aeruginosa, Salmonella enterica Typhimurium, Salmonella enterica ssp. enterica, and Bacillus cereus. Minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values were determined using concentrations from 220 to 3.44 μg mL-1. Most of the tested compounds presented MIC values ≤220 μg mL-1 for all the bacteria used in the assays. The molecular properties of the compounds were computed with the PM6 method. Through principle components analysis, the natural phenols and their semisynthetic derivatives with higher antimicrobial potential were grouped.
Synthesis method 5 - halogeno-veratraldehyde
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Paragraph 0080-0083, (2021/11/21)
The invention belongs to the field of organic chemistry, and in particular relates 5 - to a method for synthesizing halogenated O-veratraldehyde by using 4 - halogenoylguaiacol as a raw material to obtain 2 -hydroxy -3 - methoxy -5 -halogenated mandelic a
A synthetic preparation method for small carbags hydrochloric acid
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Paragraph 0176-0178, (2021/12/08)
The present invention belongs to the field of organic chemistry, relates to a method of synthesizing berberine hydrochloride, comprising: S1: with 5-halo-o-quinoastearaldehyde and piperine ethylamine to obtain N- [2-(3,4-dimethoxyphenyl-5-yl) ethyl] -1- (5-halo-2,3-dimethoxybenzyl) methylimide; S2: to obtain 2- (3,4-diimoxyphenyl) -N- (5-bromo-2,3-dimethoxybenzyl) ethylamine; S3: to obtain 2-(3,4-dimethoxyphenyl) -N- (5-bromo-2 S4: to obtain 12-halogenated berberine derivative; S5: to obtain berberine. The present invention is free from the application of the by-product o-vanillin synthesis of o-resveratal raw material constraints, synthesis of 5- substitute o-resveratal and piperine ethylamine, and the use of the two preparation of berberine hydrochloride, with raw materials readily available, mild reaction conditions, easy to operate, high chemical yield, low cost and other advantages.
Method for synthesizing eugenol
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Paragraph 0035-0036; 0041-0042; 0047-0048, (2020/08/06)
A method for synthesizing eugenol comprises the steps that firstly, guaiacol, lithium chloride and a catalytic amount of copper chloride are dissolved in glacial acetic acid, bubbling is conducted, oxygen is introduced for a reaction, and 4-chloro-2-methoxyphenol is obtained; then, 4-chloro-2-methoxyphenol reacts with alkyl halide alkyl ether in the presence of alkali to obtain 4-chloro-2-methoxy-1-alkoxy alkylphenol; 4-chloro-2-methoxy-1-alkoxy alkylphenol reacts with allyl magnesium halide in an ether solution to obtain 4-allyl-2-methoxy-1-alkoxy alkylphenol; and finally, 4-allyl-2-methoxy-1-alkoxy alkylphenol and p-toluenesulfonic acid monohydrate react in an organic solvent, and after the organic solvent is removed, residues obtained are subjected to high vacuum distillation to obtainthe eugenol product. According to the method, the problems that in the prior art, guaiacol directly reacts with 3-chloropropene to easily generate ortho-isomers difficult to separate, and the yield ofthe para-product eugenol is low are successfully solved, the quality of the eugenol product is improved, and the yield of eugenol is increased to 70% or above.
Synthetic method of eugenol
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Paragraph 0034-0035; 0040-0041; 0046-0047, (2020/08/06)
A synthetic method of eugenol comprises the following steps of: dropwise adding a halogenating reagent into guaiacol, adding an alkaline saturated solution for layering, washing with water, drying, filtering, and carrying out reduced pressure distillation to obtain 4-halogen-2-methoxyphenol; adding 4-halogen-2-methoxyphenol and alkali into an organic solvent, adding alkyl halide alkyl ether, adding water, layering, extracting the water layer with a solvent, drying the organic layer, filtering, and removing the solvent to obtain 4-halogen-2-methoxy-1-alkoxy alkylphenol; dropwise adding 4-halogen-2-methoxy-1-alkoxy alkylphenol into an ether solution of allyl magnesium halide; adding an ammonium chloride aqueous solution to obtain a mixture, carrying out reduced pressure distillation to remove ether, carrying out water layer extraction, combining ethyl acetate layers, drying, filtering, and carrying out reduced pressure distillation to obtain 4-allyl-2-methoxy-1-alkoxy alkylphenol; and mixing the product with p-toluenesulfonic acid monohydrate, stirring, carrying out reduced pressure distillation, and carrying out high vacuum distillation to obtain eugenol. The defects that in the prior art, guaiacol directly reacts with 3-chloropropene, so that ortho-position reaction is easier, and the para-position product yield is low and does not exceed 50% are overcome.
Directed Structural Transformations of Coordination Polymers Supported Single-Site Cu(II) Catalysts to Control the Site Selectivity of C-H Halogenation
Huang, Chao,Zhu, Kaifang,Zhang, Yingying,Shao, Zhichao,Wang, Dandan,Mi, Liwei,Hou, Hongwei
supporting information, p. 12933 - 12942 (2019/10/11)
A main difficulty in C-H bond functionalization is to undertake the catalyst control accurately where the reaction takes place. In this work, to achieve highly effective and regioselective single-site catalysts, a three-dimensional (3D) rhombus-like framework of {[Mn(Hidbt)DMF]·H2O}n (1) [H3idbt = 5,5′-(1H-imidazole-4,5-diyl)-bis(2H-tetrazole)] containing coordinated DMF molecules was constructed. For the dissolution-recrystallization structural transformation process, attractive structural transformations proceeded from 1 to a new crystalline species formulated as {[Mn3(idbt)2(H2O)2]·3H2O}n (2) with a 3D windowlike architecture, and then the Mn ions in 2 could be exchanged with Cu ions through cation exchange in a single-crystal to single-crystal fashion to produce the Cu-exchanged product {[Mn2Cu(idbt)2(H2O)2]·3H2O}n (2a), which had a windowlike framework like that of 2. Furthermore, 2 and 2a were used as heterogeneous catalysts for the regioselective C-H halogenation of phenols with N-halosuccinimides (NCS and NBS) to produce the site selective single monohalogenated products. It was found that the catalytic activity and site selectivity of 2a were much higher than those of 2, because the unique structural features of 2a with the uniformly dispersed CuII active centers served as a single-site catalyst with a site-isolated and well-defined platform to promote the C-H halogenation reaction in regiocontrol and guide an orientation that favored the para selectivity during the reaction process.
The Catalyst-Controlled Regiodivergent Chlorination of Phenols
Maddox, Sean M.,Dinh, Andrew N.,Armenta, Felipe,Um, Joann,Gustafson, Jeffrey L.
supporting information, p. 5476 - 5479 (2016/11/17)
Different catalysts are demonstrated to overcome or augment a substrate's innate regioselectivity. Nagasawa's bis-thiourea catalyst was found to overcome the innate para-selectivity of electrophilic phenol chlorination, yielding ortho-chlorinated phenols that are not readily obtainable via canonical electrophilic chlorinations. Conversely, a phosphine sulfide derived from 2,2′-Bis(diphenylphosphino)-1,1′-binaphthyl (BINAP) was found to enhance the innate para-preference of phenol chlorination.
Highly Selective Synthesis of Chlorophenols under Microwave Irradiation
Xiong, Yawen,Duan, Hongdong,Meng, Xia,Ding, Zhaoyun,Feng, Weichun
, (2016/06/14)
Oxychlorination of various phenols is finished in 60 minutes with high efficiency and perfect selectivity under microwave irradiation. These reactions adopt copper(II) chloride (CuCl2) as the catalyst and hydrochloric acid as chlorine source instead of expensive and toxic ones. Oxychlorination of phenols substituted with electron donating groups (methyl, methoxyl, isopropyl, etc.) at ortho- and meta-positions is accomplished with higher conversion rates, lower reaction time, and excellent selectivity. A proposed reaction mechanism is deduced; one electron transfers from CuCl2 to phenol followed by the formation of tautomeric radical that can be rapidly captured by chlorine atom and converts into para-substituted product.
Anodic coupling of guaiacol derivatives on boron-doped diamond electrodes
Kirste, Axel,Schnakenburg, Gregor,Waldvogel, Siegfried R.
supporting information; experimental part, p. 3126 - 3129 (2011/08/03)
The anodic treatment of guaiacol derivatives on boron-doped diamond electrodes (BDD) provides a direct access to nonsymmetrical biphenols, which would require a multistep sequence by conventional methods. Despite the destructive nature of BDD anodes they
Facile p-toluenesulfonic acid-promoted para-selective monobromination and chlorination of phenol and analogues
Bovonsombat, Pakorn,Ali, Rameez,Khan, Chiraphorn,Leykajarakul, Juthamard,Pla-On, Kawin,Aphimanchindakul, Suraj,Pungcharoenpong, Natchapon,Timsuea, Nisit,Arunrat, Anchalee,Punpongjareorn, Napat
experimental part, p. 6928 - 6935 (2010/10/01)
para-Regioselective bromination of phenol and analogues, promoted by p-toluenesulfonic acid, is achieved in high to excellent yields at room temperature with N-bromosuccinimide. Chlorination with N-chlorosuccinimide and catalysed by p-toluenesulfonic acid also gives para-chlorinated phenol analogues in good yields at room temperature. para-Bromination of phenol, promoted by p-toluenesulfonic acid, is achieved in excellent yields at room temperature with N-bromosuccinimide. p-Toluenesulfonic acid is also effective as a promoter of para-chlorination with N-chlorosuccinimide.