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1.
An efficient green protocol for the preparation 3,4,6-trisubstituted 2-pyridone of employing a condensation reaction of cyanoacetamide and acetylacetone in the presence of KAl(SO42·12H2O in water has been described.The present procedure offers advantage such as shorter reaction time,simple workup,and excellent yields.  相似文献   

2.
杨冬  庄荣传  宓锦校  黄雅熙 《结构化学》2021,40(1):114-124,5
Two new alkali metal germanophosphates,namely,Na3[Ge(OH)(PO4)2]·2 H2 O and Li2Na[GeO(HPO4)(PO4)],have been prepared by solvothermal method,and their crystal structures were determined by single-crystal X-ray diffraction.The title two compounds crystalize in the same orthorhombic space group Pbcm(No.57)and feature similar chain-like structure which is built from zig-zag GeO6 octahedral thread loop branched by PO4 tetrahedra.For Na3[Ge(OH)(PO4)2]·2 H2O,a=10.1650(9),b=13.1975(12),c=6.9751(7)?,V=935.73(15)?3,Z=4,R=0.0356 and wR=0.1109;and for Li2Na[GeO(HPO4)(PO4)],a=6.9855(5),b=14.5809(18),c=6.6620(5)?,V=678.56(11)?3,Z=4,R=0.0286,and w R=0.0762.The partial substitution of Na ions by Li ions not only significantly influences the total structural features and the water molecule contents,but also impacts on their thermal stabilities.Li2Na[GeO(HPO4)(PO4)]is thermally stable up to 400℃,whereas only 150℃ for Na3[Ge(OH)(PO4)2]·2 H2 O.  相似文献   

3.
ZrOCl2·8H2O catalyzed environmentally benign synthesis of isobenzofuran-1(3H)-ones are described.ZrOCl2·8H2O appeared to be an excellent catalyst for the condensation and reactions.Reaction of phthalaldehydic acid(2-carboxybenzaldehyde) with methylaryl and cyclic ketones was initiated by condensation and occurred in one step providing excellent yields(90-98%).  相似文献   

4.
闫卫红  曾宪彩 《结构化学》2021,40(3):349-356,273
Two new complexes[Cu(AQTC)0.5(H2O)3]·3H2O}n (1,H4AQTC=anthraquinone-1,4,5,8-tetracarboxylic acid) and Cu[(Py)2C(OH)2]2(H2AQTC)·2H2O (2,(Py)2CO=di-2-pyridyl ketone) have been prepared and characterized by elemental analyses and IR spectroscopy.X-ray crystallographic studies show that complex 1crystallizes in monoclinic space group C2/m and complex 2 in monoclinic space group P2_1/c.Complex 1 features a1D chain structure by carboxyl oxygen atoms.Complex 2 displays a mononuclear structure and anions and cations are separated.What's interesting is that the ligand of H4AQTC with eight carboxyl oxygen atoms and two quinone oxygen atoms does not directly coordinate with metals,and only exist as a counter-anion in complex 2.Three-dimensional structures of two complexes are formed by intermolecular interactions.The thermogravimetric analyses of two complexes are investigated.The luminescent properties of complex 1 are investigated as well.  相似文献   

5.
A microporous and robust bimetal-organic framework [Cd2Ba(NH2-BTB)2]·2(DMA)·2(H2O)(1) was constructed by mixing the heterometallic nodes and an tridentate carboxyl ligand with amino group, benefiting from the synergistic effect of active sites, exposed amino groups and ultramicroporous structure. This compound displays an extraordinary selectivity of CO2/CH4 and C2H2/CH4(16.7 and 146.3) at 298 K an...  相似文献   

6.
Co(ClO4))2·6H2O/bis-Schiff base complexes promoted the conjugate addition of indole toα,β-unsaturated ketones under mild conditions,giving the corresponding addition products with high yields.And the complex has been characterized with XRD and IR.  相似文献   

7.
曹淑华  台夕市  辛春玲 《结构化学》2021,(3):324-328,272
A novel Ca(Ⅱ) coordination polymer,[Ca L2(H2O)2]n (1,HL=4-acetylphenoxyacetic acid) has been synthesized with 4-acetylphenoxyacetic acid,Ca(ClO_4)2·4H2O and Na OH as raw materials.Complex 1 was characterized by elemental analysis and single-crystal X-ray diffraction analysis.The results show that the Ca(Ⅱ)ion is eight-coordinated in a distorted triangular dodecahedral geometric configuration with six carboxylate Oatoms of four L ligands and two O atoms of two coordinated water molecules.Complex 1 forms a one-dimensional chained structure by the bridging effect of carboxylate O atoms.The antitumor activity of HLligand and complex 1 has also been investigated.  相似文献   

8.
采用化学共沉淀方法从磷酸铁锂废料中提取FePO4·2H2O,并研究了回收过程中杂质形成的机理。在热力学计算基础上绘制了298和363 K时Fe-P-Li-H2O体系的电势(φ)-pH图,结果表明当pH≤5.0时,Fe(OH)3相可以自发地转成FePO4·2H2O相,从而得到高纯的FePO4·2H2O。但实验结果发现当溶液中铁、磷的物质的量之比(nFe∶nP)为1∶1,合成pH为1.5~2.2时得到的FePO4·2H2O中存在Fe(OH)3杂质,这是因为在共沉淀过程中少量Fe3+以Fe(OH)3快速沉淀,而陈化时Fe(OH)3相转化速率慢,因此FePO4·2H2O中含有Fe(OH)3  相似文献   

9.
Two isostructu ral Ni(Ⅱ)/Co(Ⅱ)-based metal-organic frameworks(MOFs),namely {[M3(L)2(bpb)3(H2 O)4]·2 DMF·2 H2O}n [M=Ni(HL-5,HL is short for Hui-Ling Liu);M=Co(HL-6);H3 L=2',6'-dimethyl-[1,1'-biphenyl]-3,4',5-tricarboxylic acid;bpb=1,4-bis(pyrid-4-yl)benzene],have been hydrothermally synthesized and structu rally characterized.Both HL-5 and HL-6,which have the same three-interpenetrated3 D pillared-layer framework with sqc306 type topology,present good selective methyl orange(MO)adsorption over rhodamine B(RhB).Moreover,the catalytic CO2 cycloaddition properties with epoxides of the two MOFs have also been studied at ambient pressure and temperature.  相似文献   

10.
水热条件下,合成了一个三维配位聚合物[Ni2(BDC)2(m-bix)(H2O)3·3H2O]n(1)[BDC=对苯二甲酸,m-bix=1,3-双(咪唑基-1-甲基)-苯],并通过红外,热重和X-射线单晶衍射进行了表征。X射线衍射结果表明化合物含有类似配位环境的金属2个Ni2+离子,2个BDC2-配体,1个m-bix分子,3个配位水分子和3个游离的溶剂水分子。两个Ni2+离子分别采用八面体构型,通过桥联水分子形成双核单元,然后通过全部脱质子的BDC形成三维孔洞结构,m-bix配体通过连接两类双核金属原子形成三维框架,游离水分子存在于框架之中。有趣的是,化合物的结构是单一六节点,具有自穿插特征。而且对化合物的红外和热重性质进行了表征。  相似文献   

11.
This work presents chemical modeling of solubilities of metal sulfates in aqueous solutions of sulfuric acid at high temperatures. Calculations were compared with experimental solubility measurements of hematite (Fe2O3) in aqueous ternary and quaternary systems of H2SO4, MgSO4 and Al2(SO4)3 at high temperatures. A hybrid model of ion-association and electrolyte non-random two liquid (ENRTL) theory was employed to fit solubility data in three ternary systems H2SO4–MgSO4–H2O, H2SO4–Al2(SO4)3–H2O at 235–270 °C and H2SO4–Fe2(SO4)3–H2O at 150–270 °C. Employing the Aspen Plus™ property program, the electrolyte NRTL local composition model was used for calculating activity coefficients of the ions Al3+, Mg2+ Fe3+ and SO42−, HSO4, OH, H3O+, respectively, as well as molecular species. The solid phases were hydronium alunite (H3O)Al3(SO4)2(OH)6, hematite Fe2O3 and magnesium sulfate monohydrate (MgSO4)·H2O which were employed as constraint precipitation solids in calculating the metal sulfate solubilities. A correlation for the equilibrium constants of the association reactions of complex species versus temperature was implemented. Based on the maximum-likelihood principle, the binary interaction energy parameters for the ionic species as well as the coefficients for equilibrium constants of the reactions were obtained simultaneously using the solubility data of the ternary systems. Following that, the solubilities of metal sulfates in the quaternary systems H2SO4–Fe2(SO4)3–MgSO4–H2O, H2SO4–Fe2(SO4)3–Al2(SO4)3–H2O at 250 °C and H2SO4–Al2(SO4)3–MgSO4–H2O at 230–270 °C were predicted. The calculated results were in excellent agreement with the experimental data.  相似文献   

12.
The compounds K4Ti(O2)4·2H2O, K3Ta(O2)2F4 and K2V2O3(O2)2F2 undergo photolysis in the solid state. The photolysis kinetics obey the parabolic rate equation p = kt1/2 and indicate a monoexcitation process for the photolysis. These features are similar to those reported previously for peroxo complexes. The mechanism of evolution of oxygen reported earlier appears to be the same in all these solids.  相似文献   

13.
Chromium doped (CH3)2NH2Al(SO4)2·6H2O (DMAAlS) and (CH3)2NH2Ga(SO4)2·6H2O (DMAGaS) single crystals were grown and investigated using the methods of optical spectroscopy. It was found that the Cr3+ ions in the two crystals are situated in a strong crystal field in which the 2E state is the lowest. The single narrow R-line associated with the 2E–4A2 phosphorescence of Cr3+ in DMAAlS in a ferroelectric phase indicates an undistorted octahedral site, whereas important distortion of Oh symmetry and structural disorder was inferred from spectral data obtained with DMAGaS:Cr3+ in a low temperature phase. Results of optical investigation are discussed taking into account the structural data.  相似文献   

14.
The compound [Zn(H2O)4]2[H2As6V15O42(H2O)]·2H2O (1) has been synthesized and characterized by elemental analysis, IR, ESR, magnetic measurement, third-order nonlinear property study and single crystal X-ray diffraction analysis. The compound 1 crystallizes in trigonal space group R3, a=b=12.0601(17) Å, c=33.970(7) Å, γ=120°, V=4278.8(12) Å3, Z=3 and R1(wR2)=0.0512 (0.1171). The crystal structure is constructed from [H2As6V15O42(H2O)]4− anions and [Zn(H2O)4]2+ cations linked through hydrogen bonds into a network. The [H2As6V15O42(H2O)]6− cluster consists of 15 VO5 square pyramids linked by three As2O5 handle-like units.  相似文献   

15.
Synthesis, structure, spectroscopy and thermal properties of complex [Co(NCS)2(hmt)2(H2O)2][Co(NCS)2(H2O)4] (H2O) (I), assembled by hexamethylenetetramine and octahedral Co(II) metal ions, are reported. Crystal data for I: Fw 387.34, a=9.020(8), b=12.887(9), c=7.95(1) Å, =96.73(4), β=115.36(5), γ=94.16(4)°, V=820(1) Å3, Z=2, space group=P−1, T=173 K, λ(Mo-K)=0.71070 Å, ρcalc=1.718567 g cm−3, μ=17.44 cm−1, R=0.088, Rw=0.148. An interesting two-dimensional network is assembled via hydrogen bonds through coordinated and free water molecules. The d–d transition energy levels of Co(II) ion are determined by UV–vis spectroscopy and calculated by ligand field theory. The calculated results agree well with experiment ones.  相似文献   

16.
Peter C. Junk  Jonathan W. Steed   《Polyhedron》1999,18(27):4646-3597
[Co(η2-CO3)(NH3)4](NO3)·0.5H2O and [(NH3)3Co(μ-OH)2(μ-CO3)Co(NH3)3][NO3]2·H2O were prepared by prolonged aerial oxidation of a solution of Co(NO3)2·6H2O and ammonium carbonate in aqueous ammonia. The formation of these side products highlights the richness of the chemistry of these systems and the possibility of by products if methods are not strictly adhered to. The X-ray crystal structures of [Co(η2-CO3)(NH3)4][NO3]·0.5H2O and [(NH3)3Co(μ-OH)2(μ-CO3)Co(NH3)3][NO3]2·H2O reveal a monomeric octahedral cobalt center with η2-bound CO32− in the former, while the latter consists of a dimeric array where the two cobalt centers are bridged by two OH and one μ2-CO32− groups with three terminal NH3 ligands for each Co center. In both complexes extensive hydrogen bonding interactions are evident.  相似文献   

17.
The title complex [ErY(Gly)_6(H_2O)_4](ClO_4)_6 5H_2O has been synthesized.Its crystalstructure has been determined by X-ray diffraction method.The crystal is triclinic with space groupP1.The unit cell parameters are as follows:a=11.518(4),b=14.105(7),c=15.530(6) ,α=96.61(3),β=102.74(3),γ=105.70(3)°,V=2327.7(17) ~3,Z=2,Dc=2.091g/cm~3.The structure has been refinedto a final R of 0.0785.The crystal is an infinite chain complex,in which four carboxyl groups fromglycine molecules bridge the Er(Ⅲ)and Y(Ⅲ)ion,other two carboxyl groups bridge two adjacentEr(Ⅲ)or two Y(Ⅲ)ions.  相似文献   

18.
闫广精  王春波  张月  陈亮 《燃料化学学报》2019,47(10):1163-1172
采用密度泛函理论研究了H_2O对SO_2在CaO(001)表面上吸附的影响。结果表明,以四种形式(-H_2O、-H、-OH和-H-OH)存在的H_2O使SO_2在CaO表面上的吸附构型发生改变。SO_2在不同形式H_2O基团邻位吸附时,-H使S原子的p轨道态密度峰明显左移且吸附能比洁净表面大90 kJ/mol,其余基团表面吸附能无明显变化;SO_2吸附于-OH和-H-OH生成HSO_3基团,吸附能相比于洁净表面较小,可能作为暂态结构;SO_2吸附于-H_2O生成SO_3基团,H_2O断键生成的H基团起主要吸附作用,CaO表面上生成类似Ca(OH)_2的局部结构且吸附能比洁净表面大45 kJ/mol。  相似文献   

19.
The reaction between metallic barium and fluoroisopropanol or alcoholysis of [Ba(OPri)2] produces a pentanuclear fluoroalkoxide. Its X-ray structure determination showed its formulation to correspond to Ba55-OH)[μ3-OCH(CF3)2]42-OCH(CF3)2]4 [OCH(CF3)2](THF)4(H2O)·THF. The metallic core is based on a square pyramid encapsulating an hydroxo ligand. In addition to the barium---alkoxide bonds [2.53(3)–2.86(3) Å] neutral O-donors, four THF [2.82(2)–2.86(3) Å] and one H2O [2.79(3) Å] and secondary barium---fluorine interactions [2.99(2)–3.31(2) Å] ensure high coordination numbers, from 9 to 11 for the metal centers. Hydrogen bonding between the apical fluoroisopropoxide, the water molecule and one THF molecule, non-bonded to a metal center, accounts for the stability of the hydrate and illustrates the Lewis acidity of fluoroalkoxides. Thermal decomposition leads to BaF2.  相似文献   

20.
利用精密自动绝热热量计测定了Nd(Gly)2Cl3·3H2O在80-357K和Pr(Ala)3Cl3·3H2O在80-374K温区的热容. 根据两个化合物的热容计算出了相对于参考温度298.15K的热力学函数(HT?H298.15)和(ST?S298.15). 根据热重(TG)分析结果, 提出了这两个稀土化合物可能的热分解机理. 利用溶解-反应恒温热量计测定相关化合物的溶解焓并设计盖斯热化学循环, 计算出了两个化合物的标准摩尔生成焓.  相似文献   

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