2233-18-3Relevant articles and documents
Unexpected 2,4,6-trimethylphenol oxidation in the presence of Fe(III) aquacomplexes
Aguer, Jean-Pierre,Mailhot, Gilles,Bolte, Michele
, p. 191 - 196 (2006)
2,4,6-Trimethylphenol (TMP) was efficiently oxidised by Fe(III) aquacomplexes. HPLC analysis was used to follow the kinetics of the redox process. Two degradation products were detected and identified: 2,6-dimethyl-4-(hydroxymethyl)phenol (P1) and 3,5-dimethyl-4-hydroxybenzaldehyde (P2) accounting for 100% of TMP degradation in the early stages of the reaction. The formation of the products was concomitant with the reduction of Fe(III) into Fe(II). The direct relation between TMP oxidation and the concentration of the monomeric species {Fe(H2O)5(OH)} 2+ gives evidence for the initial reaction to take place between TMP and this particular species. Moreover, the correlation between P2 formation and P1 disappearance during the reaction implies the sequence of reactions: TMP → P1 → P2. A mechanism leading to the two degradation products is proposed. the Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2006.
A highly sensitive fluorescent probe that quantifies transthyretin in human plasma as an early diagnostic tool of Alzheimer's disease
Lim, Hye Rim,Kim, Seo Yun,Jeon, Eun Hee,Kim, Yun Lan,Shin, Yu Mi,Koo, Tae-Sung,Park, Sung Jean,Hong, Ki Bum,Choi, Sungwook
, p. 10424 - 10427 (2019)
The development of sensitive and reliable fluorescent probes for the early diagnosis of Alzheimer's disease (AD) is highly challenging and plays an important role in achieving effective treatments. Herein, we designed and synthesized an indole-based fluorophore for TTR in human plasma, an important hallmark of AD pathogenesis. This robust and simple fluorescent method allows quantification of TTR in the complex biological matrix.
A NOVEL OXYGENATION OF 2,4,6-TRIMETHYLPHENOL TO 3,5-DIMETHYL-4-HYDROXYBENZALDEHYDE BY DIOXYGEN WITH COPPER(II)-AMINE COMPLEX CATALYST
Takehira, Katsuomi,Shimizu, Masao,Watanabe, Yoshihito,Orita, Hideo,Hayakawa, Takashi
, p. 2607 - 2608 (1990)
2,4,6-Trimethylphenol was efficiently oxagenated to 3,5-dimethyl-4-hydroxybenzaldehyde by molecular oxagen in the presence of catalytic amount of copper(II)chloride/amine (1/1) complex in alcoholic solvent at ambient temperature.
5-Hydroxy-2,3-dihydrobenzofuran-derived polyfunctional antioxidants: 1. Synthesis of 2-dodecylthiomethyl-5-hydroxy-2,3-dihydrobenzofurans
Yagunov,Kholshin,Kandalintseva,Prosenko
, (2017)
2-Dodecylthiomethyl-5-hydroxy-2,3-dihydrobenzofurans, new sulfur-containing analogs of tocopherols, were synthesized based on methylphenols through the intermediate preparation of 4-alkoxy-2-allylphenols and then 5-alkoxy-2-iodomethyl-2,3-dihydrobenzofura
5-Aryl-2-(3,5-dialkyl-4-hydroxyphenyl)-4,4-dimethyl- 4H-imidazole 3-oxides and their redox species: How antioxidant activity of 1-hydroxy-2,5-dihydro- 1h-imidazoles correlates with the stability of hybrid phenoxyl-nitroxides
Amitina, Svetlana A.,Artamonov, Ilya A.,Dmitrieva, Natalya A.,Kandalintseva, Natalya V.,Lomanovich, Alyona V.,Markov, Alexander F.,Mazhukin, Dmitrii G.,Ten, Yury A.,Zaytseva, Elena V.
, (2020/08/24)
Cyclic nitrones of the imidazole series, containing a sterically hindered phenol group, are promising objects for studying antioxidant activity; on the other hand, they can form persistent hybrid phenoxyl-nitroxyl radicals (HPNs) upon oxidation. Here, a series of 5-aryl-4,4-dimethyl- 4H-imidazole 3-oxides was obtained by condensation of aromatic 2-hydroxylaminoketones with 4-formyl-2,6-dialkylphenols followed by oxidation of the initially formed N-hydroxy derivatives. It was shown that the antioxidant activity of both 1-hydroxy-2,5-dihydroimidazoles and 4H-imidazole 3-oxides increases with a decrease in steric volume of the alkyl substituent in the phenol group, while the stability of the corresponding HPNs generated from 4H-imidazole 3-oxides reveals the opposite tendency.
Activating a Peroxo Ligand for C?O Bond Formation
del Río, M. Pilar,Abril, Paula,López, José A.,Sodupe, Mariona,Lledós, Agustí,Ciriano, Miguel A.,Tejel, Cristina
supporting information, p. 3037 - 3041 (2019/01/24)
Dioxygen activation for effective C?O bond formation in the coordination sphere of a metal is a long-standing challenge in chemistry for which the design of catalysts for oxygenations is slowed down by the complicated, and sometimes poorly understood, mechanistic panorama. In this context, olefin–peroxide complexes could be valuable models for the study of such reactions. Herein, we showcase the isolation of rare “Ir(cod)(peroxide)” complexes (cod=1,5-cyclooctadiene) from reactions with oxygen, and then the activation of the peroxide ligand for O?O bond cleavage and C?O bond formation by transfer of a hydrogen atom through proton transfer/electron transfer reactions to give 2-iradaoxetane complexes and water. 2,4,6-Trimethylphenol, 1,4-hydroquinone, and 1,4-cyclohexadiene were used as hydrogen atom donors. These reactions can be key steps in the oxy-functionalization of olefins with oxygen, and they constitute a novel mechanistic pathway for iridium, whose full reaction profile is supported by DFT calculations.
Phenolic Oxidation Using H2O2 via in Situ Generated para-Quinone Methides for the Preparation of para-Spiroepoxydienones
McLaughlin, Michael F.,Massolo, Elisabetta,Cope, Thomas A.,Johnson, Jeffrey S.
supporting information, p. 6504 - 6507 (2019/09/04)
Phenols are attractive starting materials for the preparation of highly substituted cyclohexane rings via dearomative processes. Herein we report an efficient preparation of dearomatized 1-oxaspiro[2.5]octa-4,7-dien-6-ones (para-spiroepoxydienones) via the nucleophilic epoxidation of in situ generated para-quinone methides from 4-(hydroxymethyl)phenols using aqueous H2O2. The developed protocol bypasses the need for stoichiometric bismuth reagents or diazomethane, which are frequently deployed for p-spiroepoxydienone preparation. The p-spiroepoxydienones are further elaborated in numerous downstream complexity-building transformations.
Magnetic nano-structured cobalt-cobalt oxide/nitrogen-doped carbon material as an efficient catalyst for aerobic oxidation of p-cresols
Liang, Cheng,Li, Xuefeng,Su, Diefeng,Ma, Qiyi,Mao, Jianyong,Chen, Zhirong,Wang, Yong,Yao, Jia,Li, Haoran
, p. 121 - 131 (2018/05/22)
Efficient aerobic oxidation has been developed for the selective preparation of a sequence of valuable p-hydroxybenzaldehydes from corresponding p-cresols, using a new magnetically separable catalyst of nano-structured cobalt-cobalt oxide/nitrogen-doped carbon (CoOx@CN) material. CoOx@CN showed high activity for the 2-methoxy-4-cresol oxidation to vanillin, giving great yield (90%) and with good turnover number (210), as well as other p-cresols in good to great yields. The catalytic performance was investigated and related to the structural, chemical and magnetic properties which determined by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FT-IR) and vibrating sample magnetometer (VSM). The effects of base to substrate molar ratio, catalyst concentration, temperature, and solvent on the conversion and selectivity patterns also have been studied. The investigation revealed that remarkable catalytic properties of CoOx@CN could be ascribed to the active species cobalt oxide, doped nitrogen and porous carbon with large surface area. The size of the catalyst is a key factor for catalyst performance. The ferromagnetic property of catalyst enables to recycle easily by an external magnetic field and reuse six successive times without significant activity loss.
Exploration of phenylpropanoic acids as agonists of the free fatty acid receptor 4 (FFA4): Identification of an orally efficacious FFA4 agonist
Sparks, Steven M.,Aquino, Christopher,Banker, Pierette,Collins, Jon L.,Cowan, David,Diaz, Caroline,Dock, Steven T.,Hertzog, Donald L.,Liang, Xi,Swiger, Erin D.,Yuen, Josephine,Chen, Grace,Jayawickreme, Channa,Moncol, David,Nystrom, Christopher,Rash, Vincent,Rimele, Thomas,Roller, Shane,Ross, Sean
, p. 1278 - 1283 (2017/06/19)
The long chain free fatty acid receptor 4 (FFA4/GPR120) has recently been recognized as lipid sensor playing important roles in nutrient sensing and inflammation and thus holds potential as a therapeutic target for type 2 diabetes and metabolic syndrome. To explore the effects of stimulating this receptor in animal models of metabolic disease, we initiated work to identify agonists with appropriate pharmacokinetic properties to support progression into in vivo studies. Extensive SAR studies of a series of phenylpropanoic acids led to the identification of compound 29, a FFA4 agonist which lowers plasma glucose in two preclinical models of type 2 diabetes.
Cu(OAc)2-catalyzed remote benzylic C(sp3)-H oxyfunctionalization for C=O formation directed by the hindered para-hydroxyl group with ambient air as the terminal oxidant under ligand- and additive-free conditions
Jiang, Jian-An,Chen, Cheng,Huang, Jian-Gang,Liu, Hong-Wei,Cao, Song,Ji, Ya-Fei
supporting information, p. 1248 - 1254 (2014/03/21)
A hindered para-hydroxyl group-directed remote benzylic C(sp3)-H oxyfunctionalization has been developed for the straightforward transformation of 2,6-disubstituted 4-cresols, 4-alkylphenols, 4-hydroxybenzyl alcohols and 4-hydroxybenzyl alkyl ethers into various aromatic carbonyl compounds. The ligand- and additive-free Cu(OAc)2-catalyzed atmospheric oxidation mediated by ethylene glycol unlocks a facile, atom-economical, and environmentally benign C=O formation for the functionalization of primary and secondary benzyl groups. Due to the pharmaceutical importance of 4-hydroxybenzaldehydes and 4-hydroxyphenones, the methodology is expected to be of significant value for both fundamental research and practical applications.
