85264-33-1Relevant academic research and scientific papers
Structural, electrochemical and magnetic analyses of a new octanuclear MnIII2MnII6 cluster with linked-defect cubane topology
Yang, Fei,Deng, Yong-Kai,Guo, Ling-Yu,Su, Hai-Feng,Jagli?i?, Zvonko,Feng, Zhen-Yu,Zhuang, Gui-Lin,Zeng, Su-Yuan,Sun, Di
, p. 1329 - 1336 (2016)
The employment of the 3,5-dimethyl-1-(hydroxymethyl)-pyrazole (Hdmhmp) ligand in a manganese carboxylate cluster afforded the new mixed-valent octanuclear manganese cluster [MnIII2MnII6O2(PhCOO)10(dmhmp)4(H2O)2]·4CH3CN (1). Complex 1 was isolated by the reaction of Mn(ClO4)2·6H2O, Hdmhmp and benzoic acid in a mixed solvent of acetonitrile and methanol. The structure of 1 can be described as a μ4-O2--linked pair of [Mn4O3] defect cubanes protected by ten PhCO2- and four μ3-dmhmp- ligands. Complex 1 is slightly soluble in acetonitrile, and high-resolution electrospray mass spectrometry (HRESI-MS) indicated that it could keep the [MnIII2MnII6O2] core integrity in solution but with detectable ligand exchange between PhCOO- and dmhmp-. The electrochemical studies show that 1 possesses a characteristic MnII → MnIII oxidation peak at +0.82 V and MnIII → MnII reduction peaks at-0.79 and-1.51 V (versus Fc/Fc+), respectively. A detailed magnetic properties investigation has revealed only a weak intramolecular antiferromagnetic interaction between the MnII and MnIII ions and no characteristic single-molecule magnetic properties.
Multifaceted Bicubane Co4Clusters: Magnetism, Photocatalytic Oxygen Evolution, and Electrical Conductivity
Xie, Wan-Feng,Guo, Ling-Yu,Xu, Jia-Heng,Jagodi?, Marko,Jagli?i?, Zvonko,Wang, Wen-Guang,Zhuang, Gui-Lin,Wang, Zhi,Tung, Chen-Ho,Sun, Di
, p. 3253 - 3261 (2016)
The use of 1-(hydroxymethyl)-3,5-dimethylpyrazole (HL), a functionalized pyrazole ligand, to assemble with CoX2(X = Cl or Br) in the presence of triethylamine under low-temperature solvothermal conditions gave rise to two tetranuclear cobalt(II) clusters, [Co4L6X2] [X = Cl (1), Br (2)]. Both CoII4clusters are isostructural and protected by four μ2-N1:O2and two μ3-N1:O3L–as well as terminal X anions to form a face-shared open bicubane structural motif. Magnetic susceptibility measurements indicated that there is an intramolecular antiferromagnetic interaction between four CoIIatoms in 1 and 2. Although the core motif of 1 and 2 is not classic Co4O4monocubane, both are active catalysts for water oxidation, and their relative O2-evolution rates are dependent on the halogen terminal ligands, which is also supported by spin-polarized density functional theory (DFT) calculations. Both clusters exhibit semiconductor behavior with σ values on the 10–9S cm–1scale at room temperature; however, mechanical iodine doping results in up to an astonishing 105-fold maximum enhancement of solid-state conductivity relative to the undoped samples. This work therefore presents a new core type of cobalt cluster that possesses photocatalytic oxygen-evolution capabilities, provides new insight into the catalysis-related mechanism based on the relative oxygen-evolution efficiency, and applies the iodine-doping strategy to boost the conductivity of cluster compounds.
An efficient process to directly convert 1-hydroxymethyl-3,5-dimethylpyrazole to Cd(ii) complexes via C-N bond creation: Cytotoxicity and factors controlling the structures
Masternak, Joanna,Barszcz, Barbara,Sawka-Dobrowolska, Wanda,Wietrzyk, Joanna,Jezierska, Julia,Milczarek, Magdalena
, p. 43962 - 43972 (2014)
We have demonstrated a simple process that involves one-pot, one-step reactions leading to efficient preparation of new cadmium complexes with N4-donating ligands [CdX2L1] (X = I- (1), Br- (2) L1 = tris(1-(3,5-dimethylpyrazolyl)methyl)amine). The most prominent feature of the synthesis is the in situ formation of a new organic tripodal ligand (L1) in a condensation reaction between a starting ligand (1-hydroxymethyl-3,5-dimethylpyrazole) and ammonia. A single-crystal X-ray analysis confirmed that the complexes obtained are monomers (1, 2) with octahedral geometry of the cadmium centres. Complex 3 has a cationic-anionic structure [Cu(LOH)2CH3OH][CdCl4] and has been synthesised by the reaction of CdO and NH4Cl in the presence of zerovalent copper (powder). IR, EPR, 1H and 13C NMR, as well as simultaneous TG/DTG were carried out to characterise the products. Moreover, we try to compare the cytotoxic profile of CdO and cadmium salts with Cd(ii) complexes. Besides [CdX2L1] (1, 2) we take into consideration [Cd2(L2)2(SCN)4(MeOH)2]n (4) and [Cd(SCN)2L1] (5) complexes. Biological studies demonstrated that Cd(ii) complexes with the N-scorpionate ligand (1, 2 and 5) have similar cytotoxicity, which points to a structure-cytotoxicity relationship. Thus, all the complexes (except 4) exhibited a lower cytotoxic activity compared to a cadmium ion in salts. This journal is
Hierarchical Assembly of a INNC0208SI320167052134nf>MnIII4} Brucite Disc: Step-by-Step Formation and Ferrimagnetism
Deng, Yong-Kai,Su, Hai-Feng,Xu, Jia-Heng,Wang, Wen-Guang,Kurmoo, Mohamedally,Lin, Shui-Chao,Tan, Yuan-Zhi,Jia, Jiong,Sun, Di,Zheng, Lan-Sun
, p. 1328 - 1334 (2016)
In search of functional molecular materials and the study of their formation mechanism, we report the elucidation of a hierarchical step-by-step formation from monomer (Mn) to heptamer (Mn7) to nonadecamer (Mn19) satisfying the relation 1 + Σn6n, where n is the ring number of the Brucite structure using high-resolution electrospray ionization mass spectrometry (HRESI-MS). Three intermediate clusters, Mn10, Mn12, and Mn14, were identified. Furthermore, the Mn19 disc remains intact when dissolved in acetonitrile with a well-resolved general formula of [Mn19(L)x(OH)y(N3)36-x-y]2+ (x = 18, 17, 16; y = 8, 7, 6; HL = 1-(hydroxymethyl)-3,5-dimethylpyrazole) indicating progressive exchange of N3- for OH-. The high symmetry (R-3) Mn19 crystal structure consists of a well-ordered discotic motif where the peripheral organic ligands form a double calix housing the anions and solvent molecules. From the formula and valence bond sums, the charge state is mixed-valent, [MnII15MnIII4]. Its magnetic properties and electrochemistry have been studied. It behaves as a ferrimagnet below 40 K and has a coercive field of 2.7 kOe at 1.8 K, which can be possible by either weak exchange between clusters through the anions and solvents or through dipolar interaction through space as confirmed by the lack of ordering in frozen CH3CN. The moment of nearly 50 NB suggests MnII-MnII and MnIII-MnIII are ferromagnetically coupled while MnII-MnIII is antiferromagnetic which is likely if the MnIII are centrally placed in the cluster. This compound displays the rare occurrence of magnetic ordering from nonconnected high-spin molecules.
New arylselanylpyrazole-copper catalysts: Highly efficient catalytic system for C–Se and C–S coupling reactions
Coelho, Felipe Lange,Dresch, Lucielle Codeim,Stieler, Rafael,Campo, Leandra Franciscato,Schneider, Paulo Henrique
, p. 19 - 26 (2019/01/04)
We describe herein the use of arylselanylpyrazole–copper complexes as versatile catalysts for C–Se and C–S coupling reactions. The performance of these complexes for C–Se reactions was investigated in chalcogenoacetylene synthesis. The reactions were carried out under mild and aerobic conditions and afforded selanylalkynes bearing a variety of electron-withdrawing and electron-donating groups. The performance of these catalysts for C–S coupling was investigated through the reaction of aryl halides with thiols and products were obtained in moderate to excellent yields. A plausible mechanism for selenoacetylene synthesis is also suggested, and the 77Se NMR results show that these arylselanylpyrazole ligands act as hemilabile ligands. High-resolution mass spectrometry was used to investigate the intermediates and also to corroborate the proposed catalytic cycle.
Nickel(II) complexes with tripodal NNN ligands as homogenous and supported catalysts for ethylene oligomerization
Tuskaev, Vladislav A.,Zubkevich, Sergei V.,Saracheno, Daniele,Gagieva, Svetlana Ch.,Dorovatovskii, Pavel V.,Kononova, Elena G.,Khrustalev, Victor N.,Zarubin, Dmitry N.,Bulychev, Boris M.,Kissin, Yury V.
, p. 29 - 38 (2019/01/04)
Four new coordination compounds of nickel (II) with derivatives of N,N-bis(pyrazol-1-ylmethyl)propylamine were synthesized; their composition and structure were confirmed with IR-spectroscopy and elemental analysis. The structures of products 13 and 15 were unambiguously established in an X-ray diffraction study. Compounds 13 and 15 crystallize in the orthorhombic space groups Pna21 and P212121 correspondingly and represent a monomeric octahedral nickel complexes, that are typical for tridentate scorpion-type ligands. New method for immobilization of nickel complexes with derivatives of N,N-bis(pyrazol-1-ylmethyl)propylamine on silica gel modified with aminopropyl groups was proposed. The EXAFS/XANES analysis indicated that Ni atom in the supported complexes adopt almost octahedral geometry, being partly surrounded by nitrogen atoms from organic ligand and partly grafted to silica surface through silanol groups, with Br? in outer coordination sphere. Both the original and the supported complexes, when activated with Et2AlCl or Et3Al2Cl3, catalyze ethylene oligomerization with the predominant formation of butene isomers. Generally, the immobilized complexes show higher activity and better selectivity towards 1-butene formation.
ZINC COMPLEX INCLUDING N,N-BISPYRAZOLYL BASED LIGAND, CATALYST FOR POLYMERIZATION OF MONOMER HAVING A RING-TYPE ESTER GROUP, AND METHOD OF FORMING POLYMER USING THE CATALYST
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Paragraph 0079-0081, (2017/07/13)
The present invention relates to a zinc complex containing an N,N-bispyrazolyl based ligand, a catalyst for polymerizing a monomer having a cyclic ester group, and a method of forming a polymer by using the same, wherein the zinc complex is represented by chemical formula 1, and in the chemical formula 1, Ar represents a cycloalkyl group, an alkoxy group, or a halogen group; L represents -(CH_2)_y- (while y is an integer of 1 to 5) or an arylene group; R_1 to R_4 represent independently hydrogen or an alkyl group; and X represents a halogen group.COPYRIGHT KIPO 2017
New N,N,N',N'-tetradentate pyrazoly agents: Synthesis and evaluation of their antifungal and antibacterial activities
Abrigach, Farid,Bouchal, Btissam,Riant, Olivier,Macé, Yohan,Takfaoui, Abdelilah,Radi, Smaail,Oussaid, Abdelouahad,Bellaoui, Mohammed,Touzani, Rachid
, p. 83 - 89 (2016/03/08)
A new library of N,N,N',N'-tetradentate pyrazoly compounds containing a pyrazole moiety was synthesized by the condensation of (3,5-dimethyl-1H-pyrazol-1-yl)methanol 2a or (1H-pyrazol-1-yl)methanol 2b with a series of primary diamines in refluxed acetonitrile for 6h. The antifungal activity against the budding yeast Saccharomyces cerevisiae, as well as the antibacterial activity against Escherichia coli of these new tetradentate ligands were studied. We found that these tetradentate ligands act specifically as antifungal agents and lack antibacterial activity. Their biological activities depend on the nature of the structure of the compounds.
Coordination of new disulfide ligands to CuIand CuII: Does a CuII μ-thiolate complex form?
Ording-Wenker, Erica C. M.,Siegler, Maxime A.,Bouwman, Elisabeth
supporting information, p. 193 - 202 (2015/03/04)
Interest in dinuclear CuII μ-thiolate and CuI disulfide complexes is triggered by their similarity with the CuA site and the possibility to control this redox equilibrium. Three new disulfide ligands L1, L3 and L4 were synthesized and reacted with CuI salts to investigate whether thiolate or disulfide species would form. The nature of L1 precludes the formation of CuII μ-thiolate species, resulting in the formation of [Cu2I(L1)(CH3CN)](BF4)2 which was characterized via single crystal X-ray crystallography. Pyrazole-containing ligands L3 and L4 form CuI complexes that are stable in solution in air for hours with half-wave potentials of approximately +0.55 V versus Ag/AgCl, indicating high stability of the CuI state rather than the CuII state. The half-wave potentials of the CuI complexes with L1 and L2 are less positive, indicating that in order to allow formation of both CuII μ-thiolate and CuI disulfide species, a half-wave potential of roughly 0 V versus Ag/AgCl would be ideal. Furthermore, CuII crystal structures with L1, L2, L3 and L4 and different counterions were compared and analyzed. Pyrazolyl-containing ligands L3 and L4 form complexes that are very similar to the complexes with pyridyl-containing ligands L1 and L2.
X-ray crystal structures and MMA polymerization of cadmium(II) complexes with bidentate pyrazole ligands: The formation of monomers or dimers as a function of a methyl substituent on the pyrazole and aniline rings
Kim, Dongil,Kim, Sunghoon,Woo, Hyun Yul,Lee, Ha-Jin,Lee, Hyosun
, p. 445 - 453 (2014/06/09)
The reaction of CdBr2·4H2O with ancillary ligands, N,N-bis(1H-pyrazolyl-1-methyl)aniline (L1), N,N-bis(1H-pyrazolyl-1-methyl)-p-methylaniline (L2), N,N-bis(1H-pyrazolyl-1-methyl)-3,5-dimethylaniline (L3), N,N-bis(3,5-dimethyl-1H-pyrazolyl-1-methyl)aniline (L4) and N,N-bis(1H-pyrazolyl-1-methyl)-2,6-dimethylaniline (L5) in ethanol yields novel Cd(II) bromide complexes, [L1CdBr2] 2, [L2CdBr2]2, [L 3CdBr2]2, [L4CdBr2] and [L5CdBr2]. The X-ray crystal structures of [L 1CdBr2]2, [L2CdBr2] 2 and [L3CdBr2]2 reveal a bromo-bridged dimeric species with crystallographic inversion symmetry. Conversely, [L4CdBr2] and [L5CdBr2] exist as monomeric complexes, presumably due to the steric hindrance between the methyl substituents of the two pyrazole groups in the ligand and cadmium centre for [L4CdBr2], and crowding around the cadmium metal by methyl substituents on the aniline residue in the ligand for [L 5CdBr2]. The geometry at each Cd(II) centre for [L 1CdBr2]2, [L2CdBr2] 2 and [L3CdBr2]2 is best described as a distorted trigonal bipyramid. A distorted trigonal bipyramid is achieved in [L4CdBr2] by coordinative interaction of the nitrogen atom of the aniline unit and the cadmium atom with a σ plane of symmetry, based on the bond length of Cd-Naniline (2.759(7) A). [L 5CdBr2] exists with a distorted tetrahedral geometry involving non-coordination of the nitrogen atom of aniline and the Cd centre, resulting in the formation of an eight-membered chelate ring. The catalytic activity of monomeric, five-coordinated [L4CdBr2] in the polymerization of methyl methacrylate (MMA) in the presence of modified methylaluminoxane (MMAO) at 60°C resulted in a higher molecular weight and a narrower polydispersity index (PDI) than those obtained with dimeric [L nCdBr2]2 (Ln=L1, L 2, L3) or monomeric tetrahedral [L5CdBr 2]. Copyright
