2409-55-4Relevant articles and documents
Spirofluorene organic laser material based on trifluoromethyl benzene functionalization, microcrystal preparation and application
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Paragraph 0026-0074, (2021/07/10)
The invention provides a spirofluorene organic laser material based on trifluoromethyl benzene functionalization. The material is characterized in that the compound takes two trifluoromethyl phenyl groups as end-capping groups and is bridged through n spirofluorene groups, and in the general formula I, R1 and R2 independently represent a straight chain, a ring-shaped chain, a branched alkyl chain and an alkoxy chain containing hydrogen or 1-12 carbon atoms, and n is 1, 2 or 3. By changing the spirofluorene groups in the middle and substituent groups on the spirofluorene groups, a molecular pi conjugated system, a topological structure, an electronic structure and solubility are regulated and controlled, and the photoelectric characteristics of the material are regulated. The structure is simple, the light and heat stability is good, the synthesis process is simple, the yield is very high, and industrialization is facilitated. The preparation of the organic microcrystal material does not need any surfactant, and the organic microcrystal material is regular in morphology and low in ASE threshold value, and can be applied to the organic electronic field of organic laser gain media and the like.
Method for preparing 2-tert-butyl p-cresol under catalysis of eutectic solvent
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Paragraph 0026-0074, (2021/07/11)
The invention discloses a method for preparing 2-tert-butyl p-cresol under catalysis of a deep-eutectic solvent, which comprises the following steps: (1) taking caprolactam as a hydrogen bond acceptor and p-toluenesulfonic acid as a hydrogen bond donor, and reacting under a stirring condition to prepare the deep-eutectic solvent; and (2) accurately weighing methylphenol and tert-butyl alcohol according to a molar ratio of (12-5): (1-3), putting the weighed methylphenol and tert-butyl alcohol into a reaction tube, adding the eutectic solvent into the reaction tube, and stirring at 25-50 DEG C for 3-8 hours to obtain the 2-tert-butyl p-cresol. According to the method, the eutecticevaporate solvent taking p-toluenesulfonic acid as a hydrogen bond donor and caprolactam as a hydrogen bond acceptor is adopted to catalyze the alkylation reaction of p-methylphenol and tert-butyl alcohol, and the catalytic activity of the eutecticevaporate solvent can be optimal by accurately controlling all parameters in the alkylation of p-methylphenol; according to the method, the conversion rate of the tert-butyl alcohol can reach the maximum value of 100%, the selectivity of the 2-tert-butyl p-cresol can reach 99%, and the reaction does not corrode equipment, so that the method has a wide application prospect.
Single Electron Transfer-Induced Selective α-Oxygenation of Glycine Derivatives
Císa?ová, Ivana,Jahn, Ullrich,K?nig, Burkhard,Moser, Johannes,Venugopal, Navyasree,Vojtí?ková, Margaréta
supporting information, (2021/11/03)
Modification of amino acids is an important strategy in organic and bioorganic chemistry. In contrast to common side-chain functionalization, backbone modification is much less explored. Especially glycine units seem to be attractive and versatile since a wide range of functionality can be potentially introduced. We report here oxidative modification of glycinates that are stable and enable further functionalization. Selective glycinate enolate oxidation by TEMPO or a FeCp2PF6/TEMPO reagent combination provides stable alkoxyamines in good to excellent yields. The methodology is expanded to glycine-containing dipeptides demonstrating selective oxygenation at the glycine unit. The orthogonal reactivity potential of oxygenated glycines for transformation to other amino acid derivatives is explored.
Enantioselective Kinetic Resolution/Desymmetrization of Para-Quinols: A Case Study in Boronic-Acid-Directed Phosphoric Acid Catalysis
Huang, Banruo,He, Ying,Levin, Mark D.,Coelho, Jaime A. S.,Bergman, Robert G.,Toste, F. Dean
supporting information, p. 295 - 301 (2019/11/03)
A chiral phosphoric acid-catalyzed kinetic resolution and desymmetrization of para-quinols operating via oxa-Michael addition was developed and subsequently subjected to mechanistic study. Good to excellent s-factors/enantioselectivities were obtained over a broad range of substrates. Kinetic studies were performed, and DFT studies favor a hydrogen bonding activation mode. The mechanistic studies provide insights to previously reported chiral anion phase transfer reactions involving chiral phosphate catalysts in combination with boronic acids. (Figure presented.).
Reductive Aromatization of Quinols with B2pin2 as Deoxidizing Agent
Liu, Bin,Xu, Yin,Luo, Zhibin,Xie, Jimin
, p. 1022 - 1024 (2020/03/19)
We have demonstrated B2pin2 as superior deoxidizing agent for the reductive deoxygenation of quinol derivatives under basic conditions. A wide range of highly functionalized phenols were obtained in good yields including a complex drug molecule, which revealed the high functional group tolerance of this protocol.
Alkylation of Phenols with tert-Butanol Catalyzed by H-Form of Y Zeolites with a Hierarchical Porous Structure
Bayguzina,Makhiyanova,Khazipova,Khusnutdinov
, p. 1554 - 1559 (2019/10/14)
tert-Butyl-substituted phenols have been synthesized via the reaction of phenol, o-, m-, and p-cresols with tert-butanol under the action of CBr4-promoted Y-zeolites in the H-form with a hierarchical porous structure.
A kind of using modified Y zeolite catalytic synthesis of 2-tert-butyl-P-cresol method
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Paragraph 0024; 0025, (2017/03/14)
The invention belongs to the technical field of organic synthesis, and relates to a method for synthesizing 2-tertiary butyl-p-cresol through catalysis of modified Y zeolite. The method comprises the following step: with modified Y zeolite as a catalyst, carrying out alkylation reaction on an alkylating agent and p-cresol under ordinary pressure so as to prepare the 2-tertiary butyl-p-cresol, wherein the modified Y zeolite is prepared through carrying out ion exchange on NaY zeolite through ammonium chloride, manganous nitrate, lanthanum nitrate or cerous nitrate solutions. The method for synthesizing the 2-tertiary butyl-p-cresol has the advantages of availability in reaction at normal pressure, low reaction temperature, short reaction time, high conversion rate of p-cresol, good selectivity of 2-tertiary butyl-p-cresol, simpleness and convenience in operation, environmental protection and so on.
Experimental Investigation on Upgrading of Lignin-Derived Bio-Oils: Kinetic Analysis of Anisole Conversion on Sulfided CoMo/Al2O3 Catalyst
Rahimpour, Hamid Reza,Saidi, Majid,Rostami, Parisa,Gates, Bruce C.,Rahimpour, Mohammad Reza
, p. 702 - 713 (2016/09/28)
Kinetics of the hydroprocessing of anisole, a compound representative of lignin-derived bio-oils, catalyzed by a commercial sulfided CoMo/Al2O3, was determined at 8–20 bar pressure and 573–673 K with a once-through flow reactor. The catalyst was sulfided in an atmosphere of H2 + H2S prior to the measurement of its performance. Selectivity-conversion data were used as a basis for determining an approximate, partially quantified reaction network showing that hydrodeoxygenation (HDO), hydrogenolysis, and alkylation reactions take place simultaneously. The data indicate that these reactions can be stopped at the point where HDO is virtually completed and hydrogenation reactions (and thus H2 consumption) are minimized. Phenol was the major product of the reactions, with direct deoxygenation of anisole to give benzene being kinetically almost insignificant under our conditions. We infer that the scission of the Cmethyl–O bond is more facile than the scission of the Caromatic–O bond, so that the HDO of anisole likely proceeds substantially through the reactive intermediate phenol to give transalkylation products such as 2-methylphenol. The data determine rates of formation of the major primary products. The data show that if oxygen removal is the main processing goal, higher temperatures and lower pressures are favored.
Multi SO3H supported on carbon nanotubes: A practical, reusable, and regioselective catalysts for the tert-butylation of p-cresol under solvent-free conditions
Fareghi-Alamdari, Reza,Golestanzadeh, Mohsen,Zekri, Negar,Mavedatpoor, Zeinab
, p. 537 - 549 (2015/03/05)
The present study describes the synthesis, characterization, and catalytic activity of sulfonated multi-walled carbon nanotubes and sulfonated single-walled carbon nanotubes in the tert-butylation of p-cresol. The catalysts were prepared using a chemical and simple process and it characterized by scanning electron microscopy, Fourier transform infrared, and Raman spectroscopy, thermogravimetric analysis, and acid-base titration. The sulfonated multi-walled carbon nanotubes and sulfonated single-walled carbon nanotubes have been used as practical heterogeneous catalytic systems in the tert-butylation of p-cresol under solvent-free conditions. Sulfonated multi-walled carbon nanotubes with the highest total density of SO3H groups possessed high activity for p-cresol conversion and high selectivity than the sulfonated single-walled carbon nanotubes. This methodology offers some advantages of high selectivity, and high yields, easy work-up, solvent-free conditions, and reusable catalyst. Moreover, the catalytic system was used in scale-up under similar optimized reaction conditions.
Synthesis, characterization and investigation of catalytic activity of Cu1-xCoxFe2O4 nanocatalysts in t-butylation of p-cresol
Alamdari, Reza Fareghi,Hosseinabadi, Zahra,Khouzani, Masoud Farhadi
, p. 827 - 834 (2012/11/13)
In this work, tertiary butylation of p-cresol was carried out in the presence of Cu1-xCoxFe2O4 (x = 0 to 1) nanocatalysts by employing methyl-tert-butyl ether (MTBE) and tert-butyl alcohol (TBA) as alkylation agents. Effects of temperature, mole ratio, type and catalyst composition, time and solvent in reaction conditions were investigated. These nanocatalysts were synthesized using hydrothermal method. The characterization of these catalysts was investigated by means of X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FT-IR). These nanocatalysts can be recovered and recycled. A good correlation was found between the activity, in terms of p-cresol conversion and various product selectivities for this reaction, and also the acid-base properties of the catalysts. Nano-sized Cu0.5Co0.5Fe 2O4, in comparison to the other nanocatalysts discussed in this report is the most active nanocatalyst. The only product of this reaction is 2-t-butyl p-cresol with selectivity of 100% and p-cresol conversion is 70%. The possible mechanism for this reaction system was discussed based on the reaction results. The reaction mechanism proposed involves the interaction of phenoxide from phenol and the tert-butyl cation from isobutene on Cu 1-xCoxFe2O4. Indian Academy of Sciences.
