5315-25-3Relevant academic research and scientific papers
Synthesis of a new tetradentate chelator with 1-Hydoroxy-2(1H)-pyridinone (HOPO) as chelating unit: Interaction with Fe (III), solution thermodynamics and DFT studies
Baral, Minati,Dash, Dibyajit,Kanungo, B. K.
, (2020)
1,2-Hydroxypyridinone (1,2-HOPO) forms very stable transition metal complexes that may be useful in various ways, among these the iron complexes have been long used for the treatment of iron overload diseases like β-Thalassemia. A new tetradentate chelator, 1-hydroxy-N-[3-[2-[2-[3-[(1-hydroxy-6-oxo-pyridine-2carbonyl)amino]propoxy]ethoxy]ethoxy]propyl]-6-oxo-pyridine-2-carboxamide (L) having two 1,2-HOPO units with long chain amine backbone has been synthesized and characterized through various techniques like TLC, solubility, melting point, FT-IR, 1H NMR, 13C NMR, ESI-MS, UV–Vis and emission spectroscopy. The protonation constants of the ligand were determined by both potentiometrically as well as spectrophotometrically in aqueous medium at 25° ±1 °C. The solution thermodynamics of the ligand its Fe(III) complexes in aqueous solution were also studied. The pKa values for ligand are found to be 7.34 and 6.06 and the formation constant of metal complex (M2L3) is found to be logβ230 = 42.45. To support the experimental data, theoretical calculation at DFT level of theory was done using GGA (Gradient Generalized Approximation) with BLYP functional and DZP basis set. The results of calculated thermodynamic properties suggest that, ΔG follows the same trend of protonation as determined by potentiometry and spectrophotometry. Studies of the DFT optimized structures of LH2, LH? shows that, there is π stacking interaction between the hydroxypyridinone rings in the species and the intramolecular π-stacking interaction decreases as the distance between two pyridine ring increases upon deprotonation and was found to be 2.7, 3.2 and 14.6 ? for LH2, LH? and L?2 respectively.
Synthesis and physico-chemical properties of homoleptic copper(I) complexes with asymmetric ligands as a dssc dye
Hatano, Mayuka,Inomata, Tomohiko,Kawai, Yuya,Kitagawa, Takuma,Masuda, Hideki,Matsunaga, Ayaka,Ozawa, Tomohiro,Wasada-Tsutsui, Yuko
supporting information, (2021/11/27)
To develop low-cost and efficient dye-sensitized solar cells (DSSCs), we designed and prepared three homoleptic Cu(I) complexes with asymmetric ligands, M1, M2, and Y3, which have the advantages of heteroleptic-type complexes and compensate for their synthetic challenges. The three copper(I) complexes were characterized by elemental analysis, UV-vis absorption spectroscopy, and electrochemical measurements. Their absorption spectra and orbital energies were evaluated and are discussed in the context of TD-DFT calculations. The complexes have high VOC values (0.48, 0.60, and 0.66 V for M1, M2, and Y3, respectively) which are similar to previously reported copper(I) dyes with symmetric ligands, although their energy conversion efficiencies are relatively low (0.17, 0.64, and 2.66%, respectively).
NEW COMPOUND
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Paragraph 0316; 0320, (2019/11/26)
PROBLEM TO BE SOLVED: To provide a new compound that does not have structural similarity to ceramide and has excellent CERT inhibitory activity. SOLUTION: The present invention provides a new compound of structural formula (I). A bond group -X- is cis-cyclopropyl-, R1, R2, R3, R4, and R5 independently represent a hydrogen atom, a halogen atom, a linear or branched C1-C8 alkyl group that may have a halogen atom, or OR6. SELECTED DRAWING: Figure 1 COPYRIGHT: (C)2020,JPOandINPIT
Transition-metal-free decarboxylative halogenation of 2-picolinic acids with dihalomethane under oxygen conditions
Zhang, Xitao,Feng, Xiujuan,Zhang, Haixia,Yamamoto, Yoshinori,Bao, Ming
supporting information, p. 5565 - 5570 (2019/10/22)
A convenient and efficient method for the synthesis of 2-halogen-substituted pyridines is described. The decarboxylative halogenation of 2-picolinic acids with dihalomethane proceeded smoothly via N-chlorocarbene intermediates to afford 2-halogen-substituted pyridines in satisfactory to excellent yields under transition-metal-free conditions. This new type of decarboxylative halogenation is operationally simple and exhibits high functional-group tolerance.
Photocatalytic CO2 Reduction by Trigonal-Bipyramidal Cobalt(II) Polypyridyl Complexes: The Nature of Cobalt(I) and Cobalt(0) Complexes upon Their Reactions with CO2, CO, or Proton
Shimoda, Tomoe,Morishima, Takeshi,Kodama, Koichi,Hirose, Takuji,Polyansky, Dmitry E.,Manbeck, Gerald F.,Muckerman, James T.,Fujita, Etsuko
supporting information, p. 5486 - 5498 (2018/05/17)
The cobalt complexes CoIIL1(PF6)2 (1; L1 = 2,6-bis[2-(2,2′-bipyridin-6′-yl)ethyl]pyridine) and CoIIL2(PF6)2 (2; L2 = 2,6-bis[2-(4-methoxy-2,2′-bipyridin-6′-yl)ethyl]pyridine) were synthesized and used for photocatalytic CO2 reduction in acetonitrile. X-ray structures of complexes 1 and 2 reveal distorted trigonal-bipyramidal geometries with all nitrogen atoms of the ligand coordinated to the Co(II) center, in contrast to the common six-coordinate cobalt complexes with pentadentate polypyridine ligands, where a monodentate solvent completes the coordination sphere. Under electrochemical conditions, the catalytic current for CO2 reduction was observed near the Co(I/0) redox couple for both complexes 1 and 2 at E1/2 = -1.77 and -1.85 V versus Ag/AgNO3 (or -1.86 and -1.94 V vs Fc+/0), respectively. Under photochemical conditions with 2 as the catalyst, [Ru(bpy)3]2+ as a photosensitizer, tri-p-tolylamine (TTA) as a reversible quencher, and triethylamine (TEA) as a sacrificial electron donor, CO and H2 were produced under visible-light irradiation, despite the endergonic reduction of Co(I) to Co(0) by the photogenerated [Ru(bpy)3]+. However, bulk electrolysis in a wet CH3CN solution resulted in the generation of formate as the major product, indicating the facile production of Co(0) and [Co-H]n+ (n = 1 and 0) under electrochemical conditions. The one-electron-reduced complex 2 reacts with CO to produce [Co0L2(CO)] with νCO = 1894 cm-1 together with [CoIIL2]2+ through a disproportionation reaction in acetonitrile, based on the spectroscopic and electrochemical data. Electrochemistry and time-resolved UV-vis spectroscopy indicate a slow CO binding rate with the [CoIL2]+ species, consistent with density functional theory calculations with CoL1 complexes, which predict a large structural change from trigonal-bipyramidal to distorted tetragonal geometry. The reduction of CO2 is much slower than the photochemical formation of [Ru(bpy)3]+ because of the large structural changes, spin flipping in the cobalt catalytic intermediates, and an uphill reaction for the reduction to Co(0) by the photoproduced [Ru(bpy)3]+.
METHOD OF PRODUCING PHENOLIC COMPOUND
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Paragraph 0029, (2018/03/30)
PROBLEM TO BE SOLVED: To provide a method of efficiently producing a phenolic compound by direct oxidation of an aromatic compound. SOLUTION: The present invention provides a method of producing a phenolic compound by oxidizing an aromatic compound by an oxidizer in the presence of a copper complex having as a ligand a compound represented by the formula (I) or (II) in the figure. (In the formulas, R1 to R9 each independently represent a methylene group or ethylene group.) SELECTED DRAWING: None COPYRIGHT: (C)2018,JPOandINPIT
METHOD OF PRODUCING PHENOLIC COMPOUND
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Page/Page column 9; 13, (2017/04/27)
PROBLEM TO BE SOLVED: To provide a method of efficiently producing a phenolic compound by direct oxidation of an aromatic compound. SOLUTION: A phenolic compound is produced by oxidation of an aromatic compound by an oxidant in the presence of a binuclear nickel complex having a ligand being a compound represented by the formula (I) or (II) in the figure. SELECTED DRAWING: None COPYRIGHT: (C)2017,JPOandINPIT
A 2-cyano-6-methyl pyridine preparation method (by machine translation)
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Paragraph 0028; 0029, (2016/10/07)
The aim of the invention is to overcome the defects in the prior art, provides a 2-cyano-6-methyl pyridine preparation method, which belongs to the technical field of synthesis of pharmaceutical intermediates. The method is, will hydrobromidum and 2-amino-6-methyl pyridine mixed, heat insulation; and then cooling the solution, adding to the solution bromine Br 2, then maintain the low-temperature reaction; and then to the solution in the low temperature by adding sodium nitrite aqueous solution in the reaction; the end of the reaction the temperature of the reaction solution, adjusts pH value, then through steam distillation to obtain 2-bromo-6-methylpyridine; the cuprous cyanide and lithium bromide is added to the mass is 2-bromo-6-methylpyridine quality 2-5 times in DMF, after heating the solution, is added 2-bromo-6-methylpyridine, reaction of the; cooling the solution after the reaction, water, through the water vapor distillation to obtain the product. The security of operation of this method, low toxicity, high yield, is suitable for industrial production. (by machine translation)
Template synthesis, characterization, and antimicrobial activity of a new lead (II) Schiff base complex
Beynek, Nesrin,Tan, Nurcihan,Beynek, Hayrettin
, p. 145 - 150 (2015/12/09)
A novel lead (II) complex of Schiff base containing three bipyridine units was synthesized by the template reaction between a new amine compound, 6-methyl-6′-(2-aminophenoxymethyl)-2,2′-bipyridine, and 2,2′-bipyridine-6,6′-dicarboxaldehyde in the presence of a Pb(II) perchlorate ion. The new amino compound and Schiff base complex, [PbL](ClO4)2·2H2O, were characterized by using matrix-assisted laser desorption/ionization with time-of-flight mass spectroscopy, FAR FT-IR, UV/visible spectroscopy, 1H NMR, elemental analyses (CHN), and molar conductivity measurements. Then the synthesized complex was screened in vitro for its antibacterial and antifungal activities against three Gram-negative and two Gram-positive bacteria and also against Candida albicans as a fungus by the microdilution broth method as a minimal inhibitory concentration. [PbL](ClO4)2·2H2O exhibits moderate activity on Staphylococcus aureus and Listeria monocytogenes when compared with standard drug and also shows moderate antifungal activity on the fungus Candida albicans.
Template synthesis and spectral characterization of new Lead(II)-Schiff base macrocyclic complexes incorporating phenanthroline and/or bipyridine units
Beynek,Tan,Beynek
, p. 4141 - 4144 (2015/12/23)
Lead(II) complexes of Schiff-bases containing phenanthroline and/or bipyridine units were synthesized by the template reaction between new diamine compound, 6,6'-bis(2-aminophenoxymethyl)-2,2'-bipyridine and 2,2-bipyridine-6,6-dicarboxaldehyde or 1,10-phenanthroline- 2,9-dicarboxaldehyde in the presence of metal ions. These complexes, [PbL1]( ClO4)2and [PbL2](NO3)2, were characterized and investigated by using; MALDI-TOF and Q-TOF-MS spectroscopy, FTIR, UV/Visible spectroscopy, 1H NMR, Elemental analyses (CHN), magnetic susceptibility and molar conductivity measurements.
