55489-38-8Relevant academic research and scientific papers
Nickel-Catalyzed Decarboxylation of Aryl Carbamates for Converting Phenols into Aromatic Amines
Nishizawa, Akihiro,Takahira, Tsuyoshi,Yasui, Kosuke,Fujimoto, Hayato,Iwai, Tomohiro,Sawamura, Masaya,Chatani, Naoto,Tobisu, Mamoru
supporting information, p. 7261 - 7265 (2019/05/16)
Herein, we describe a new catalytic approach to accessing aromatic amines from an abundant feedstock, namely phenols. The most reliable catalytic method for converting phenols to aromatic amines uses an activating group, such as a trifluoromethane sulfonyl group. However, this activating group is eliminated as a leaving group during the amination process, resulting in significant waste. Our nickel-catalyzed decarboxylation reaction of aryl carbamates forms aromatic amines with carbon dioxide as the only byproduct. As this amination proceeds in the absence of free amines, a range of functionalities, including a formyl group, are compatible. A bisphosphine ligand immobilized on a polystyrene support (PS-DPPBz) is key to the success of this reaction, generating a catalytic species that is significantly more active than simple nonsupported variants.
Optimization of N-Substituted Oseltamivir Derivatives as Potent Inhibitors of Group-1 and -2 Influenza A Neuraminidases, Including a Drug-Resistant Variant
Zhang, Jian,Poongavanam, Vasanthanathan,Kang, Dongwei,Bertagnin, Chiara,Lu, Huamei,Kong, Xiujie,Ju, Han,Lu, Xueyi,Gao, Ping,Tian, Ye,Jia, Haiyong,Desta, Samuel,Ding, Xiao,Sun, Lin,Fang, Zengjun,Huang, Boshi,Liang, Xuewu,Jia, Ruifang,Ma, Xiuli,Xu, Wenfang,Murugan, Natarajan Arul,Loregian, Arianna,Huang, Bing,Zhan, Peng,Liu, Xinyong
, p. 6379 - 6397 (2018/07/15)
On the basis of our earlier discovery of N1-selective inhibitors, the 150-cavity of influenza virus neuraminidases (NAs) could be further exploited to yield more potent oseltamivir derivatives. Among the synthesized compounds, 15b and 15c were exceptionally active against both group-1 and -2 NAs. Especially for 09N1, N2, N6, and N9 subtypes, they showed 6.80-12.47 and 1.20-3.94 times greater activity than oseltamivir carboxylate (OSC). They also showed greater inhibitory activity than OSC toward H274Y and E119V variant. In cellular assays, they exhibited greater potency than OSC toward H5N1, H5N2, H5N6, and H5N8 viruses. 15b demonstrated high metabolic stability, low cytotoxicity in vitro, and low acute toxicity in mice. Computational modeling and molecular dynamics studies provided insights into the role of R group of 15b in improving potency toward group-1 and -2 NAs. We believe the successful exploitation of the 150-cavity of NAs represents an important breakthrough in the development of more potent anti-influenza agents.
Solvent-free mechanochemical Buchwald-Hartwig amination of aryl chlorides without inert gas protection
Shao, Qiao-Ling,Jiang, Zhi-Jiang,Su, Wei-Ke
supporting information, p. 2277 - 2280 (2018/05/16)
A solvent-free Buchwald-Hartwig amination had been developed under high-speed ball-milling conditions, which afforded the desired products with moderate to high yields. The addition of sodium sulfate was found to be crucial for improving both the performance and the reproducibility. Comparative solvent-free stirring experiments implicated the importance of mechanical interaction for the transformation, and the inert gas was proved to be unnecessary for this amination.
Direct arylation of tertiary amines via aryne intermediates using diaryliodonium salts
Zhang, Zhiang,Wu, Xunshen,Han, Jianwei,Wu, Wenjun,Wang, Limin
supporting information, p. 1737 - 1741 (2018/04/02)
With a strategy by using diaryliodonium salts as the precursors of benzynes, direct N-arylation of tertiary amines with diaryliodonium salts was reported. Thus, the desired aromatic tertiary amines with a wide range of substituents were synthesized in moderate to excellent yields of 55–91%.
A mechanical to urge the enters the carbon - [...] forming method (by machine translation)
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Paragraph 0042; 0043; 0044; 0046; 0057, (2018/09/21)
The invention discloses a mechanical to urge the enters the carbon - [...] forming method, said method comprising: in order to type 2 shown in formulae of organic amine 3 shown the chlorinated aromatic hydrocarbon as the raw material, the catalyst, ligand, in the presence of alkali and additive, the reaction is carried out by the mechanical grinding method, after the reaction mixture after the separation and purification, obtains the type 1 compound shown; in the present invention relates to mechanical grinding promotion to the chlorinated aromatic hydrocarbon as the substrate of the Buchwald - Hartwig reaction mainly adopts the organic phosphonate ligands, in the palladium catalyst under the action of the organic amine compound with the chlorinated aromatic hydrocarbon of the between the coupling, so as to obtain high yield of the target product, the majority of the reaction can be 90% or more yield. The mild reaction conditions, can be in the 1 - 2 H to complete the reaction. (by machine translation)
Styryl cyanine dye fluorescence probe for detecting ambient viscosity and preparation method of styryl cyanine dye fluorescence probe
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Paragraph 0027; 0030; 0031, (2017/09/13)
The invention provides a styryl cyanine dye fluorescence probe for detecting ambient viscosity and a preparation method of the styryl cyanine dye fluorescence probe. The styryl cyanine dye fluorescence probe is formed by connecting N-methyldiphenylamine and benzothiazole through vinyl. The method comprises the following steps: 1) preparing N-methyldiphenylamine; 2) dissolving N-methyldiphenylamine and phosphorus oxychloride in N,N-dimethylformamide, reacting in an ice-water bath, and reacting at a room temperature for not less than 8 hours so as to obtain a compound 3; 3) dissolving 2-methylbenzothiazole and benzyl bromide, reacting at the temperature of 90-130 DEG C for 1-6 hours so as to obtain a compound 4; 4) dissolving the compound 3 and the compound 4, reacting at the temperature of 75-90 DEG C for not less than 12 hours, thereby obtaining the product. The synthetic method disclosed by the invention is simple, and the product is high in emission wavelength, large in Stokes shift, high in sensitivity and high in selectivity, can serve as a fluorescent dye, can be applied to detecting the viscosity of the mixed solution and has the potential of being applied to viscosity measurement in cells.
Styrylcyanine-based fluorescent probes with red-emission and large Stokes shift for the detection of viscosity
Cao, Xiangbin,Liu, Jianhui,Hong, Pan,Li, Guanglan,Hao, Ce
, p. 444 - 451 (2017/07/04)
Based on the mechanism of intramolecular charge transfer (ICT), two new styrylcyanine dyes, DPA-1 and DPA-2, composed of an electron-rich N-phenylaniline and a cationic benzothiazene connected with ethylene(s) bridge, were designed and synthesized. These two dyes exhibited red-emission (653/607?nm) and simultaneously impressive large Stokes shift (111/92?nm) due to intramolecular charge transfer effect, twisted geometry and extended conjugation system. When their solution viscosity increased from 1.01?cP to 234?cP in the water-glycerol system, the fluorescence intensity of the synthetic dyes was enhanced by 81-fold and 64-fold, respectively. Additionally, a favorable linear relationship between the fluorescence intensity and the environmental viscosity was observed within the above viscosity range for the obtained samples (R2?>?0.99), which led to the establishment of a method for the quantitative determination of the solution viscosity. Such dyes with improved photophysical properties, including emission wavelength and Stokes shift, could be used as promising candidates for intracellular viscosity detection. Moreover, the mechanism of fluorescence emission of the resultant products toward viscosity was further investigated. Of the two probes studies, DPA-1 is better than DPA-2 in terms of emission wavelength, Stokes shift and the sensitivity of the fluorescence intensity to viscosity.
Multipodal arrangement of push-pull chromophores: a fundamental parameter affecting their electronic and optical properties
Klikar,Kityk,Kulwas,Mikysek,Pytela,Bure?
supporting information, p. 1459 - 1472 (2017/02/23)
A series of model push-pull molecules with linear, quadrupolar, and tripodal arrangements, a varyingly substituted amino donor, two acceptors, and a partially extended π-system has been prepared. Two peripheral electron acceptors, namely N,N′-dibutylbarbituric acid and dicyanovinyl, were employed. The fundamental properties of 24 push-pull chromophores were investigated by differential scanning calorimetry, electrochemistry, one-photon absorption spectroscopy, photoinduced piezooptics, and were supported by DFT calculations. Thorough structure-property relationships were elucidated, while a significant influence of the structural arrangement/branching on the electronic and optical properties has been revealed. The fundamental optoelectronic properties of push-pull molecules are affected by their arrangement (linear/quadrupolar/tripodal), the peripheral acceptor attached, extension and planarization of the π-system, and also by the type of auxiliary N-substituent.
Nucleophilicity Parameters of Stabilized Iodonium Ylides for Characterizing Their Synthetic Potential
Chelli, Saloua,Troshin, Konstantin,Mayer, Peter,Lakhdar, Sami,Ofial, Armin R.,Mayr, Herbert
supporting information, p. 10304 - 10313 (2016/09/03)
Kinetics and mechanisms of the reactions of the β-dicarbonyl-substituted iodonium ylides 1(a-d) with several π-conjugated carbenium and iminium ions have been investigated. All reactions proceed with rate-determining attack of the electrophile at the nucleophilic carbon center of the ylides to give iodonium ions, which rapidly expel iodobenzene and undergo different subsequent reactions. The second-order rate constants k2 for the reactions of the iodonium ylides with benzhydrylium ions correlate linearly with the electrophilicity parameters E of the benzhydrylium ions and thus follow the linear free energy relationship log k(20 °C) = sN(N + E) (eq 1), where electrophiles are characterized by one parameter (E), while nucleophiles are characterized by two parameters: the nucleophilicity N and the susceptibility sN. The nucleophilicity parameters 4 + at the carbanionic center of Meldrum's acid or dimedone, respectively, reduces the nucleophilicity by approximately 10 orders of magnitude. The iodonium ylides 1(a-d) thus have nucleophilicities similar to those of pyrroles, indoles, and silylated enol ethers and, therefore, should be suitable substrates in iminium-activated reactions. Good agreement of the measured rate constant for the cyclopropanation of the imidazolidinone-derived iminium ion 10a with the iodonium ylide 1a with the rate constant calculated by eq 1 suggests a stepwise mechanism in which the initial nucleophilic attack of the iodonium ylide at the iminium ion is rate-determining. The reaction of cinnamaldehyde with iodonium ylide 1a catalyzed by (5S)-5-benzyl-2,2,3-trimethyl-imidazolidin-4-one (11a, MacMillan's first-generation catalyst) gives the corresponding cyclopropane with an enantiomeric ratio of 70/30 and, thus, provides proof of principle that iodonium ylides are suitable substrates for iminium-activated cyclopropanations.
TRANSITION-METAL-FREE N-ARYLATION OF TERTIARY AMINES USING ARYNES
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Paragraph 0029; 0037, (2015/01/16)
The present invention relates to transition-metal-free process for the synthesis of tertiary arylamines comprises coupling reaction between arynes and N,N-dimethyl aniline compounds in presence of 18-crown-6, KF and THF.
