85264-33-1Relevant articles and documents
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Dvoretzky,Richter
, p. 1285,1287 (1950)
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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.
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.
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.
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.
