6291-84-5Relevant articles and documents
A Nanocrystal Catalyst Incorporating a Surface Bound Transition Metal to Induce Photocatalytic Sequential Electron Transfer Events
Beard, Matthew C.,Chen, Xihan,Han, Chuang,Lin, Yixiong,Martin, Jovan San,Miller, Collin,Wang, Xiaoming,Yamamoto, Nobuyuki,Yan, Yanfa,Yan, Yong,Yazdi, Sadegh,Zeng, Xianghua
supporting information, p. 11361 - 11369 (2021/08/16)
Heterogeneous photocatalysis is less common but can provide unique avenues for inducing novel chemical transformations and can also be utilized for energy transductions, i.e., the energy in the photons can be captured in chemical bonds. Here, we developed a novel heterogeneous photocatalytic system that employs a lead-halide perovskite nanocrystal (NC) to capture photons and direct photogenerated holes to a surface bound transition metal Cu-site, resulting in a N-N heterocyclization reaction. The reaction starts from surface coordinated diamine substrates and requires two subsequent photo-oxidation events per reaction cycle. We establish a photocatalytic pathway that incorporates sequential inner sphere electron transfer events, photons absorbed by the NC generate holes that are sequentially funneled to the Cu-surface site to perform the reaction. The photocatalyst is readily prepared via a controlled cation-exchange reaction and provides new opportunities in photodriven heterogeneous catalysis.
A process for the preparation of alfuzosin hydrochloride method (by machine translation)
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Paragraph 0023; 0024; 0026; 0030; 0031; 0032, (2017/08/29)
The invention relates to a process for the preparation of alfuzosin hydrochloride method, method comprises the following steps: (1) 15 °C following, acrylonitrile into the the methylamine is mellow solution to stir, by distillation to obtain (I); (2) to (I) is dripped reducing agent in an organic solvent, heating to reflux, then slowly sequentially into the 25% sodium hydroxide solution and distilled water, by the distillation treatment to obtain the (II); (3) under dry condition, the thionyl chloride is slowly dripped into the 2 - tetrahydrofuran formic acid, a 2 - tetrahydrofuran chloride; (4) the temperature control in the 5 - 15 °C conditions, will be 2 - tetrahydrofuran formyl the chlorine drips into containing acid, organic solvent and (II) of the mixed solution, then completing the stirring 3 hours, for 25% sodium hydroxide solution to neutralize, by organic solvent extraction, (III) be; (5) to (III) with 2 - chloro - 4 - amino - 6, 7 - dimethoxy quinazoline in presence of organic solvent, reflux stirring 4 - 10 hours, cooling and filtering, and steaming and removing the organic solvent, acetone dispersed precipitate solid, then re-crystallizing mixed solvent, to get the alfuzosin hydrochloride (IV). (by machine translation)
Continuous chemoselective methylation of functionalized amines and diols with supercritical methanol over solid acid and acid-base bifunctional catalysts
Oku, Tomoharu,Arita, Yoshitaka,Tsuneki, Hideaki,Ikariya, Takao
, p. 7368 - 7377 (2007/10/03)
The selective N-methylation of bifunctionalized amines with supercritical methanol (scCH3OH) promoted by the conventional solid acids (H-mordenite, β-zeolite, amorphous silica-alumina) and acid-base bifunctional catalysts (Cs-P-Si mixed oxide and γ-alumina) was investigated in a continuous-flow, fixed-bed reactor. The use of scCH 3OH in the reaction of 2-aminoethanol with methanol (amine/CH 3OH = 1/10.8) over the solid catalysts led to a significant improvement in the chemoselectivity of the N-methylation. Among the catalysts examined, the Cs-P-Si mixed oxide provided the most efficient catalyst performance in terms of selectivity and reactivity at 300 °C and 8.2 MPa; the N-methylation selectivity in the products reaching up to 94% at 86% conversion. The present selective methylation was successfully applied to the synthesis of N-methylated amino alcohols and diamines as well as O-methylated ethylene glycol. Noticeably, ethoxyethylamine was less reactive, suggesting that the hydroxy group of the amino alcohols is a crucial structural factor in determining high reactivity and selectivity, possibly because of the tethering effect of another terminus, a hydroxo group, to the catalyst surface. The magic-angle-spinning NMR spectroscopy and X-ray diffraction analysis of the Cs-P-Si mixed oxide catalyst revealed that the acidic and basic sites originate from P2O5/SiO2 and Cs/SiO2, respectively, and the weak acid-base paired sites are attributed to three kinds of cesium phosphates on SiO2. The weak acid-base sites on the catalyst surface might be responsible for the selective dehydrative methylation.
Specific binding assay compound with inhibitive self-quenching characteristics
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, (2008/06/13)
Disclosed is an assay system including a compound comprising an analyte-specific moiety having substituted thereon a polymer comprising plurality of self-quenching emitter moieties and a plurality of isocharged functionality separating the emitter moieties. The present invention provides compounds that overcome the undesirable effects of self-quenching when multiple emitter moieties are used for labelling of assay reagents. Avoidance of this self-quenching phenomenon by the compounds of the invention makes it possible to introduce a more concentrated degree of labelling on to analyte-specific molecules such as oligo nucleotide probes, antibodies and other specific binding proteins and analyte-specific polysaccharides. Therefor, it is possible to effect greater assay sensitivity because the number of labels per recognition molecule(analyte-specific moiety) can be increased beyond the point previously possible without the reduction in signal caused by self-quenching.
Poly-bis-triazinylimides, their preparation
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, (2008/06/13)
Poly-bis-triazinylimides of the formula STR1 are prepared from bis-(2,4-dichloro-1,3,5-triazin-6-yl)imides and polyalkylpiperidylamines. They are used as light stabilizers for polymers.
