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841.
Complexes of Cr(III):Cu(II) with the glyoxylate dianion as ligand were synthesized in the range of cation atomic ratios (0.01–8):1.0.
The results of non-isothermal analysis of the synthesized compounds correlated with the results of IR and UV-VIS spectroscopy,
and gas chromatography of the volatile products of the decomposition allowed the formulation of a mechanism for the decomposition
of the complex with Cr(III):Cu(II)=2:1 and the assumption that the other complexes are mixtures of this with the homopolynuclear
complexes of Cr(III) and Cu(II), depending on the ratio of the cations Cr(III):Cu(II).
The thermal conversion of the complexes takes place at relatively low temperatures, with partial transformation of the ligand
into oxalate and of the oxide mixture into CuCrO4.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
842.
The tricyclic azoalkanes, (1α,4α,4aα,7aα)‐4,4a,5,6,7,7a‐hexahydro‐1,4,8,8‐tetramethyl‐1,4‐methano‐1H‐cyclopenta[d]pyridazine ( 1c ), (1α,4α,4aα,6aα)‐4,4a,5,6,6a‐pentahydro‐1,4,7,7‐tetramethyl‐1,4‐methano‐1H‐cyclobuta[d]pyridazine ( 1d ), (1α,4α,4aα,6aα)‐4,4a,6a‐trihydro‐1,4,7,7‐tetramethyl‐1,4‐methano‐1H‐cyclobuta[d]pyridazine ( 1e ), and (1α,4α,4aα,5aα)‐4,4a,5,5a‐tetrahydro‐1,4,6,6‐tetramethyl‐1,4‐methano‐1H‐cyclopropa[d]pyridazine ( 1f ), as well as the corresponding housanes, the 2,3,3,4‐tetramethyl‐substituted tricyclo[3.3.0.02,4]octane ( 2c ), tricyclo[3.2.0.02,4]heptane ( 2d ), and tricyclo[3.2.0.02,4]hept‐6‐ene ( 2e ), were subjected to γ‐irradiation in Freon matrices. The reaction products were identified with the use of ESR and, in part, ENDOR spectroscopy. As expected, the strain on the C‐framework increases on going from the cyclopentane‐annelated azoalkanes and housanes ( 1c and 2c ) to those annelated by cyclobutane ( 1d and 2d ), by cyclobutene ( 1e and 2e ), and by cyclopropane ( 1f ). Accordingly, the products obtained from 1c and 2c in all three Freons used, CFCl3, CF3CCl3, and CF2ClCFCl2, were the radical cations 3c .+ and 2c .+ of 2,3,4,4‐tetramethylbicyclo[3.3.0]oct‐2‐ene and 2,3,3,4‐tetramethylbicyclo[3.3.0]octane‐2,4‐diyl, respectively. In CFCl3 and CF3CCl3 matrices, 1d and 2d yielded analogous products, namely the radical cations 3d .+ and 2d .+ of 2,3,4,4‐tetramethylbicyclo[3.2.0]hept‐2‐ene and 2,3,3,4‐tetramethylbicyclo[3.2.0]heptane‐2,4‐diyl. The radical cations 3c .+ and 3d .+ and 2c .+ and 2d .+ correspond to their non‐annelated counterparts 3a .+ and 3b .+, and 2a .+ and 2b .+ generated previously under the same conditions from 2,3‐diazabicyclo[2.2.1]hept‐2‐ene ( 1a ) and bicyclo[2.1.0]pentane ( 2a ), as well as from their 1,4‐dimethyl derivatives ( 1b and 2b ). However, in a CF2ClCFCl2 matrix, both 1d and 2d gave the radical cation 4d .+ of 2,3,3,4‐tetramethylcyclohepta‐1,4‐diene. Starting from 1e and 2e , the radical cations 4e .+ and 4e′ .+ of the isomeric 1,2,7,7‐ and 1,6,7,7‐tetramethylcyclohepta‐1,3,5‐trienes appeared as the corresponding products, while 1f was converted into the radical cation 4f .+ of 1,5,6,6‐tetramethylcyclohexa‐1,4‐diene which readily lost a proton to yield the corresponding cyclohexadienyl radical 4f .. Reaction mechanisms leading to the pertinent radical cations are discussed. 相似文献
843.
Nihal Kan Kaynar Metin Yavuz Hasan Tanak Songul Şahin Orhan Büyükgüngör Erbil Ağar 《Crystallography Reports》2018,63(3):375-378
The molecular structure of the title compound, C21H15Br1N2O2, was characterized by single crystal X-ray diffraction. The compound crystallizes in the triclinic sp. gr. \(P\bar 1\) with Z = 2. The molecule is not planar: the dihedral angle between the planes of two aromatic rings [C1/C6] and [C16/C21] is 84.9(2)°. The other dihedral angle between two aromatic rings [C9/C14] and [C16/C21] is 88.8(2)°. The title compound exists as a phenol-imine tautomer, in which a strong intramolecular O–H···N hydrogen bond is formed. This study verifies the preference of the phenol-imine tautomeric form in the solid state. A π–π stacking interactions are also observed, which may influence crystal stability: the distance between centroids is 3.702(2) Å. 相似文献
844.
A sensitive and selective method of analysis was constructed by the the combination of praseodymium oxide and carbon nanotubes. The charge transfer resistance (Rct) values of 109 in 1 × 10−3 M K3[Fe(CN)6] and 79 Ω in 5 × 10−6 M dopamine indicate that Pr6O11@MWCNTs/GCE enables an excellent electron pathway between electrolyte and electrode. The platform was successfully applied for the determination of dopamine in the presence of tramadol, paracetamol and ascorbic acid. The platform exhibited a remarkable decrease in ▵Ep for DA. A dynamic linear range from 1.2 × 10−9 M to 1.8 × 10−5 M was obtained with an LOD of 1.0 × 10−10 M. Such a sensitive and selective method of analysis makes Pr6O11@MWCNTs/GCE of high interest to observe trace level of DA with good accuracy and precision. 相似文献