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31.
(2R,3aR,8bR)- and (2S,3aS,8bS)-2-Methyl indoline dye tetrabutylammonium carboxylates exhibited the highest conversion efficiency among four regio and stereo isomers. These indoline dyes also showed higher conversion efficiency than DN350.  相似文献   
32.
Coordination polymers are a thriving class of functional solid‐state materials and there have been noticeable efforts and progress toward designing periodic functional structures with desired geometrical attributes and chemical properties for targeted applications. Self‐assembly of metal ions and organic ligands is one of the most efficient and widely utilized methods for the construction of CPs under hydro(solvo)thermal conditions. 2‐(Pyridin‐3‐yl)‐1H‐imidazole‐4,5‐dicarboxylate (HPIDC2−) has been proven to be an excellent multidentate ligand due to its multiple deprotonation and coordination modes. Crystals of poly[aquabis[μ3‐5‐carboxy‐2‐(pyridin‐3‐yl)‐1H‐imidazole‐4‐carboxylato‐κ5N1,O5:N3,O4:N2]copper(II)dicopper(I)], [CuIICuI2(C10H5N3O4)2(H2O)]n, (I), were obtained from 2‐(pyridin‐3‐yl)‐1H‐imidazole‐4,5‐dicarboxylic acid (H3PIDC) and copper(II) chloride under hydrothermal conditions. The asymmetric unit consists of one independent CuII ion, two CuI ions, two HPIDC2− ligands and one coordinated water molecule. The CuII centre displays a square‐pyramidal geometry (CuN2O3), with two N,O‐chelating HPIDC2− ligands occupying the basal plane in a trans geometry and one O atom from a coordinated water molecule in the axial position. The CuI atoms adopt three‐coordinated Y‐shaped coordinations. In each [CuN2O] unit, deprotonated HPIDC2− acts as an N,O‐chelating ligand, and a symmetry‐equivalent HPIDC2− ligand acts as an N‐atom donor via the pyridine group. The HPIDC2− ligands in the polymer serve as T‐shaped 3‐connectors and adopt a μ3‐κ2N,O2N′,O′:κN′′‐coordination mode, linking one CuII and two CuI cations. The Cu cations are arranged in one‐dimensional –Cu1–Cu2–Cu3– chains along the [001] direction. Further crosslinking of these chains by HPIDC2− ligands along the b axis in a –Cu2–HPIDC2−–Cu3–HPIDC2−–Cu1– sequence results in a two‐dimensional polymer in the (100) plane. The resulting (2,3)‐connected net has a (123)2(12)3 topology. Powder X‐ray diffraction confirmed the phase purity for (I), and susceptibilty measurements indicated a very weak ferromagnetic behaviour. A thermogravimetric analysis shows the loss of the apical aqua ligand before decomposition of the title compound.  相似文献   
33.
The significant variety in the crystal structures of rare‐earth carboxylate complexes is due to both the large coordination numbers of the rare‐earth cations and the ability of the carboxylate anions to form several types of bridges between rare‐earth metal atoms. Therefore, these complexes are represented by mono‐, di‐ and polynuclear complexes, and by coordination polymers. The interaction of LnCl3(thf)x (Ln = Eu or Y; thf is tetrahydrofuran) with sodium or diethylammonium diphenylacetate in methanol followed by recrystallization from a DME/THF/hexane solvent mixture (DME is 1,2‐dimethoxyethane) leads to crystals of the non‐isomorphic dinuclear complexes tetrakis(μ‐2,2‐diphenylacetato)‐κ4O:O′;κ3O,O′:O′;κ3O:O,O′‐bis[(1,2‐dimethoxyethane‐κ2O,O′)(2,2‐diphenylacetato‐κ2O,O′)europium(III)], [Eu(C14H11O2)6(C4H10O2)2], (I), and tetrakis(μ‐2,2‐diphenylacetato)‐κ4O:O′;κ3O,O′:O′;κ3O:O,O′‐bis[(1,2‐dimethoxyethane‐κ2O,O′)(2,2‐diphenylacetato‐κ2O,O′)yttrium(III)], [Y(C14H11O2)6(C4H10O2)2], (II), possessing monoclinic (P21/c) symmetry. The [Ln(Ph2CHCOO)3(dme)]2 molecule (Ln = Eu or Y) lies on an inversion centre and exhibits three different coordination modes of the diphenylacetate ligands, namely bidentate κ2O,O′‐terminal, bidentate μ2‐κ1O1O′‐bridging and tridentate μ2‐κ1O2O,O′‐semibridging. The terminal and bridging ligands in (I) are disordered over two positions, with an occupancy ratio of 0.806 (2):0.194 (2). The interaction of EuCl3(thf)2 with Na[Ph3CCOO] in methanol followed by crystallization from hot methanol produces crystals of tetrakis(methanol‐κO)tris(2,2,2‐triphenylacetato)‐κ4O:O′;κO‐europium(III) methanol disolvate, [Eu(C19H15O2)3(CH3OH)4]·2CH3OH, (III)·2MeOH, with triclinic (P) symmetry. The molecule of (III) contains two O,O′‐bidentate and one O‐monodentate terminal triphenylacetate ligand. (III)·2MeOH possesses one intramolecular and four intermolecular hydrogen bonds, forming a [(III)·2MeOH]2 dimer with two bridging methanol molecules.  相似文献   
34.
Organotincompoundsareextensivelystudiedfortheirbiologicalactivity'.Organogermaniumisanotherkindofelementthathasawiderangeofbiologicalactivity=.Tolinkbiologicalactivepropertiesoforganotinandorganogermaniumcompounds.wehavepreviouslyreportedthebiologicalactivityoftrialkyltingermylpropionates'andanticanceractivityofdibutyltindigermylpropionates'.ItiswellknownthatTorque(his[tri(2-methyl-2-phenylpropyl)tin]oxide)iswidelyusedinagricultureasanacaricide.Inthispaper,asthecontinuationofourpreviouswork"'…  相似文献   
35.
The complex [Cu(HGLYO)2(bipy)] ( I ) and two new copper(II) coordination polymers with the formulas {[Cu(GLYO)1‐x(ox)x(bipy)]·2.5H2O}n [GLYO = glycolato dianion, ox = oxalato dianion, bipy = 2, 2′‐bipyridine, x = 0.56 (in II ) or 0.71 (in III )] were synthesized using copper(II) glycolate as starting material and were characterized by IR, UV‐Vis and EPR spectrometry, by magnetic measurements ( II and III ), and by single‐crystal X‐ray diffractometry. Both II and III crystallized as one‐dimensional polymers composed of Cu2O2‐centred dimers with a Cu‐Cu distance of 3.282(1)Å (mean of II and III ) that are linked by Cu2(OCO)2 rings with a Cu‐Cu distance of 5.237(1)Å (mean of II and III ), both dianions acting as (μ‐1, 1, 2, 3) three‐way bridges connecting the two copper atoms of one dimer with one copper atom of a neighbouring dimer. Each copper atom is coordinated tetragonally in a CuN2O4 chromophore. In the mononuclear complex I the copper atom has a tetragonally distorted octahedral environment.  相似文献   
36.
A homologous series of binuclear mixed-valent diruthenium tetracarboxylates, Ru2(O2C(CH2)n?2CH3)4DHDP (DHDP = di(hexadecyl)phosphate axial anion, n = 10, 12, 14, 16, and 18), have been synthesized and characterized, and the liquid crystalline properties of these compounds were examined. All the compounds exhibit a room-temperature crystalline lamellar phase and a high temperature (above 140°) Colh mesophase. Another, probably semi-crystalline, lamellar intermediate phase has also been found for all the studied compounds but for the n = 18 derivative. Comparison with related mesogenic homologous series where the equatorial ligands are also linear carboxylates, but the axial anions bear just one aliphatic chain (carboxylates, octylsulfonate, and dodecylsulfate), shows that the presence of a second aliphatic chain in the axial anion both lowers the transition temperatures and modifies the nature of the intermediate lamellar phase. Structural models at the molecular level are suggested for the crystalline lamellar and the Colh phases.  相似文献   
37.
Summary A simple and general method for the determination of both C1−C10 alkyl sulfonates and alkyl carboxylates using the same basic methodology, based on High Performance ion Chromatography, using relatively simple eluent systems allowing fast analysis with both high sensitivity and accuracy is presented.  相似文献   
38.
利用ESR电子自旋捕捉技术,研究了甲酸钠,乙酸钠,草酸钾等羧酸盐的水溶液及其含有AgBr的分散体系在不同光照条件下自由基的产生.结果表明:某些羧酸盐(特别是甲酸盐)自身具有光解性,而且AgBr的存在对其光解过程有促进作用.这对研究羧酸盐掺杂乳剂尤其是甲酸盐掺杂乳剂的增感机理有重要意义.  相似文献   
39.
《Tetrahedron letters》2019,60(27):1769-1772
Direct oxidation of silyl ethers to silyl esters, using RuO4 formed in situ, is reported. The reaction was optimized to minimize formation of the corresponding carboxylic acid product whose formation pathway appears to be solvent dependent. The reaction is tolerant of halides, nitriles, nitro groups, esters, epoxides, and ketones.  相似文献   
40.
Based on the bond-valence sum model the continual transition between the bidentate and monodentate bonding mode of carboxylato group and minimum of Cu–O bond lengths were estimated. The dependence of Cu⋯Cu separation on Cu–N bond length in binuclear Cu(II) carboxylates with caffeine were derived and fitted to the observed data. The crystal structure of [Cu2(2-bromopropanoato)4(caffeine)2] has been determined by X-ray crystallography. The structure consists of centrosymmetric binuclear units where the two Cu atoms are coordinated by four disordered bridging 2-bromopropionates and two caffeine ligands at the apices of a bicapped square prism. Both 2-bromopropionates show disorder of their –Br and –CH3 substituents. Stacking π·π interactions between the adjacent caffeine molecules link the complex units in 1-D networks. The binuclear structure of the studied compound is consistent with magnetic data and EPR spectrum.  相似文献   
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