2402-97-3Relevant articles and documents
Rational engineering of dimeric Dy-based Single-Molecule Magnets for surface grafting
Yi, Xiaohui,Pointillart, Fabrice,Le Guennic, Boris,Jung, Julie,Daiguebonne, Carole,Calvez, Guillaume,Guillou, Olivier,Bernot, Kevin
, p. 41 - 47 (2019)
The deposition of Single-Molecule Magnets (SMMs) on surfaces is a mandatory step toward their possible use as data-storage units or qubits. In this study we report the structural and magnetic characterization of two parent compounds of a well-known SMM called DyPyNO, ([Dy(hfac)3(PyNO)]2 with hfac = hexafluoroacetylacetonate and PyNO = pyridine-N-oxide), that are targeted to be deposited on gold surfaces. Thio-substitution of the pyridine ring of these dimers is expected to provide good anchoring group toward deposition on gold. We have investigated two significantly different geometries of the anchoring groups in dimers 1 and 2. Interestingly, despite these strong differences, SMM behavior is remarkably well-preserved in the polycrystalline material offering possibilities to graft these SMMs on surface.
Synthesis of dicationic carbazole and 4′-amino-(3,3'-bipyridine)-4-ol and the spectral characteristics of carbazoles
Wang,Li,Ye,Guo,Jia
, p. 4632 - 4636 (2013)
The dicationic carbazole compound, 3,6-dimethyl-3,6-diazacarbazole diiodide (8) was prepared with 3-bromopyridine as a starting material by a six-step synthesis. The intermediates and target compound were confirmed by IR, NMR and MS. Meanwhile, UV-visible and fluorescent characteristics of 3,6-diazacarbazole (7) and 3,6-dimethyl-3,6-diazacarbazole diiodide (8) were investigated. It was found that fluorescence decay over time of dicationic carbazole existed in low ionic strength and high ionic strength could stabilize the fluorescence of dicationic carbazole.
Visible-Light-Induced Decarboxylative Acylation of Pyridine N-Oxides with α-Oxocarboxylic Acids Using Fluorescein Dimethylammonium as a Photocatalyst
Hou, Chuanfu,Sun, Shouneng,Liu, Ziqi,Zhang, Hui,Liu, Yue,An, Qi,Zhao, Jian,Ma, Junjie,Sun, Zhizhong,Chu, Wenyi
supporting information, p. 2806 - 2812 (2021/04/15)
Herein, the development of a visible-light-induced catalytic system to achieve the decarboxylative acylation of pyridine N-oxides with α-oxocarboxylic acids, at room temperature and using the organic dye fluorescein dimethylammonium as a new type of photocatalyst, is reported. A series of 2-arylacylpyridine N-oxides were selectively synthesized in moderate to good yields by controlling the polarity of the reaction solvent. The developed strategy was successfully applied in the synthesis of an important intermediate of the drug, acrivastine, on a gram scale. Notably, this is the first time that fluorescein dimethylammonium has been used to catalyze the Minisci-type C?H decarboxylative acylation reaction. The mechanism of decarboxylative acylation was studied by capturing adducts of acyl radicals and 1,1-diphenylethylene to confirm a radical mechanism. The disclosed catalytic system provides a green synthetic strategy for decarboxylative acylation without the use of additional oxidants or metal catalysts. (Figure presented.).
Synthesis method of (3-cyclopropylpyridin-2-yl) methylamine hydrochloride
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Paragraph 0028-0031; 0047-0050; 0066-0069; 0085-0088, (2020/07/08)
The invention provides a synthesis method of (3-cyclopropylpyridin-2-yl) methylamine hydrochloride, and belongs to the technical field of synthesis of organic chemical intermediates. The preparation method comprises the following steps: reacting 3-bromo-2-cyanopyridine with cyclopropylboronic acid, a phosphine ligand, an alkali and a catalyst under the protection of nitrogen, then reacting with hydrogen under the action of the catalyst, reacting with di-tert-butyl dicarbonate and alkali, and finally reacting with an organic solvent solution of hydrogen chloride to obtain a target product (3-cyclopropylpyridin-2-yl) methylamine hydrochloride. The 3-bromo-2-cyanopyridine is prepared by taking 3-bromopyridine as a raw material and carrying out nitrogen oxidation and cyanation. The method is reasonable in process design, simple in experimental operation and easy to control.
Synthesis method of (3-cyclopropylpyridin-2-yl) methylamine
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Paragraph 0016, (2020/07/28)
The invention belongs to the technical field of medical intermediates, and particularly relates to a synthesis method of (3-cyclopropylpyridin-2-yl) methylamine. The synthesis method of the (3-cyclopropylpyridin-2-yl) methylamine is provided for the first time, a synthesis route is provided for the synthesis method of the (3-cyclopropylpyridin-2-yl) methylamine, the synthesis method of the (3-cyclopropylpyridin-2-yl) methylamine is short in route, reasonable in design, easy to operate and easy to control, and meanwhile the yield of the obtained product is high.
Method for catalyzing vitamin A isomerization with ruthenium catalyst
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Paragraph 0066; 0069-0070, (2020/04/22)
The invention provides a method for catalyzing vitamin A isomer conversion with a ruthenium catalyst. According to the method, a ruthenium compound is used as a catalyst, various vitamin A cis-isomerswith low biological activity can be converted into all-trans-isomers with high biological activity in a high proportion in the presence of an auxiliary agent, and the cis-isomers comprise 9-cis-isomers, 11-cis-isomers and 13-cis-isomers. The method has the characteristics of cheap and easily available catalyst, less catalyst dosage, mild reaction conditions, low reaction cost, high isomerizationefficiency and the like.
Visible-Light-Induced ortho-Selective Migration on Pyridyl Ring: Trifluoromethylative Pyridylation of Unactivated Alkenes
Jeon, Jinwon,He, Yu-Tao,Shin, Sanghoon,Hong, Sungwoo
supporting information, p. 281 - 285 (2019/11/26)
The photocatalyzed ortho-selective migration on a pyridyl ring has been achieved for the site-selective trifluoromethylative pyridylation of unactivated alkenes. The overall process is initiated by the selective addition of a CF3 radical to the alkene to provide a nucleophilic alkyl radical intermediate, which enables an intramolecular endo addition exclusively to the ortho-position of the pyridinium salt. Both secondary and tertiary alkyl radicals are well-suited for addition to the C2-position of pyridinium salts to ultimately provide synthetically valuable C2-fluoroalkyl functionalized pyridines. Moreover, the method was successfully applied to the reaction with P-centered radicals. The utility of this transformation was further demonstrated by the late-stage functionalization of complex bioactive molecules.
Recyclable anhydride catalyst for H2O2 oxidation:: N -oxidation of pyridine derivatives
Gajeles, Ghellyn,Kim, Se Mi,Lee, Kyung-Koo,Lee, Sang Hee,Yoo, Jong-Cheol
, p. 9165 - 9171 (2020/03/13)
The catalytic efficiency and recyclability of poly(maleic anhydride-alt-1-octadecene) (Od-MA) and poly(maleic anhydride-alt-1-isobutylene) (Bu-MA) were evaluated for use in the development of a metal-free, reusable catalyst for the oxidation of pyridines to pyridine N-oxides in the presence of H2O2. The Od-MA catalyst was easily recovered via filtration with recovery yields exceeding 99.8%. The catalyst retained its activity after multiple uses and did not require any treatment for reuse. The Od-MA and H2O2 catalytic system described herein is eco-friendly, operationally simple, and cost-effective; thus, it is industrially applicable. Od-MA and H2O2 could potentially be used in place of percarboxylic acid as an oxidant in a wide range of oxidation reactions.
Strategic Approach on N-Oxides in Gold Catalysis – A Case Study
Schie?l, Jasmin,Stein, Philipp M.,Stirn, Judith,Emler, Kirsten,Rudolph, Matthias,Rominger, Frank,Hashmi, A. Stephen K.
supporting information, p. 725 - 738 (2018/10/20)
An extensive kinetic study of selected key reactions of (oxidative) gold catalysis concentrates on the decrease of the catalytic activity due to inhibition of the gold(I) catalyst caused by pyridine derivatives that are obtained as by-products if N-oxides are applied as oxygen donors. The choice of the examined pyridine derivatives and their corresponding N-oxides has been made regardless of their commercial availability; particular attention has been paid to the practical benefit which up to now has been neglected in most of the reaction screenings. The test reactions were monitored by GC and 1H NMR spectroscopy. The received reaction constants provide information concerning a correlation between the electronic structure of the heterocycle and the catalytic activity. Based on the collected kinetic data, it was possible to develop a basic set of three N-oxides which have to be taken into account in further oxidative gold(I)-catalyzed reactions. (Figure presented.).
An one-pot two-step automated synthesis of [18F]T807 injection, its biodistribution in mice and monkeys, and a preliminary study in humans
Huang, Ya-Yao,Chiu, Ming-Jang,Yen, Ruoh-Fang,Tsai, Chia-Ling,Hsieh, Hao-Yu,Chiu, Ching-Hung,Wu, Chi-Han,Hsin, Ling-Wei,Tzen, Kai-Yuan,Cheng, Cheng-Yi,Ma, Kuo-Hsing,Shiue, Chyng-Yann
, (2019/08/01)
[18F]T807 is a potent tau protein imaging agent. In order to fulfill the demand from preclinical and clinical studies, we developed an automated one-pot two-step synthesis of this potent tau imaging agent and studied its stability, and dosimetr
