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1.
Syntheses, crystal structures and thermal behavior of two new hydrated cerium(III) sulfates are reported, Ce2(SO4)3·4H2O ( I ) and β‐Ce2(SO4)3·8H2O ( II ), both forming three‐dimensional networks. Compound I crystallizes in the space group P21/n. There are two non‐equivalent cerium atoms in the structure of I , one nine‐ and one ten‐fold coordinated to oxygen atoms. The cerium polyhedra are edge sharing, forming helically propagating chains, held together by sulfate groups. The structure is compact, all the sulfate groups are edge‐sharing with cerium polyhedra and one third of the oxygen atoms, belonging to sulfate groups, are in the S–Oμ3–Ce2 bonding mode. Compound II constitutes a new structure type among the octahydrated rare‐earth sulfates which belongs to the space group Pn. Each cerium atom is in contact with nine oxygen atoms, these belong to four water molecules, three corner sharing and one edge sharing sulfate groups. The crystal structure is built up by layers of [Ce(H2O)4(SO4)]nn+ held together by doubly edge sharing sulfate groups. The dehydration of II is a three step process, forming Ce2(SO4)3·5H2O, Ce2(SO4)3·4H2O and Ce2(SO4)3, respectively. During the oxidative decomposition of the anhydrous form, Ce2(SO4)3, into the final product CeO2, small amount of CeO(SO4) as an intermediate species was detected. 相似文献
2.
Gaballa AS Teleb SM Müller T 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,70(5):1187-1192
The synthesis of Ce(IV) complexes [Ce(sac)(2)(SO(4))(H(2)O)(4)] (1) and [Ce(sac)(2) (SO(4))(PyOH)(2)] (2) (sac=saccharinate, PyOH=2-hydroxypyridine) starting with sodium saccharinate is described. Their vibrational and nuclear magnetic resonance ((1)H, (13)C) spectra as well as their thermal mode of degradation were investigated. The data indicate that sac in complex 1 behaves as a monodentate ligand through the nitrogen atoms. Saccharinato ligand in complex 2 shows different mode of coordination, where it behaves as tridentate and binds Ce(IV) through its carbonylic oxygen, nitrogen and sulphonylic oxygen atoms. The most probable structure in complex 2 is that, units of [Ce(sac)(2)(SO(4))(PyOH)(2)] are linked by bridges of the O- of sac sulphonyl leading to polymeric chains. 相似文献
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4.
Three new alkali metal transition metal sulfate‐oxalates, RbFe(SO4)(C2O4)0.5 · H2O and CsM(SO4)(C2O4)0.5 · H2O (M = Mn, Fe) were prepared through hydrothermal reactions and characterized by single‐crystal X‐ray diffraction, solid state UV/Vis/NIR diffuse reflectance spectroscopy, infrared spectra, thermogravimetric analysis, and powder X‐ray diffraction. The title compounds all crystallize in the monoclinic space group P21/c (no. 14) with lattice parameters: a = 7.9193(5), b = 9.4907(6), c = 8.8090(6) Å, β = 95.180(2)°, Z = 4 for RbFe(SO4)(C2O4)0.5 · H2O; a = 8.0654(11), b = 9.6103(13), c = 9.2189(13) Å, β = 94.564(4)°, Z = 4 for CsMn(SO4)(C2O4)0.5 · H2O; and a = 7.9377(3), b = 9.5757(4), c = 9.1474(4) Å, β = 96.1040(10)°, Z = 4 for CsFe(SO4)(C2O4)0.5 · H2O. All compounds exhibit three‐dimensional frameworks composed of [MO6] octahedra, [SO4]2– tetrahedra, and [C2O4]2– anions. The alkali cations are located in one‐dimensional tunnels. 相似文献
5.
Novel Halogenochalcogeno(IV) Acids: [H3O(Benzo‐18‐Crown‐6)]2[Te2Br10] and [H5O2(Dibenzo‐24‐Crown‐8)]2[Te2Br10] Systematic studies on halogenochalcogeno(IV) acids containing tellurium and bromine led to the new crystalline phases [H3O(Benzo‐18‐Crown‐6)]2[Te2Br10] ( 1 ) and [H5O2(Dibenzo‐24‐Crown‐8)]2[Te2Br10] ( 2 ). The [Te2Br10]2‐ anions consists of two edge‐sharing distorted TeBr6 octahedra, the oxonium cations are stabilized by crownether. ( 1 ) crystallizes in the monoclinic space group P21/n with a = 14.520(5) Å, b = 22.259(6) Å, c = 16.053(5) Å, β = 97.76(3)° and Z = 4, whereas ( 2 ) crystallizes in the triclinic space group with a = 11.005(4) Å, b = 12.103(5) Å, c = 14.951(6) Å, α = 71.61(3)°, β = 69.17(3)°, γ = 68.40(3)° and Z = 1. 相似文献
6.
Synthesis of 3‐(ω‐Hydroxyalkoxy)isobenzofuran‐1(3H)‐ones by Trifluoroacetic Acid‐Mediated Lactonization of tert‐Butyl 2‐(1,3‐Dioxol‐2‐yl)‐ or 2‐(1,3‐Dioxan‐2‐yl)benzoates 下载免费PDF全文
An efficient two‐step method for the preparation of 3‐(2‐hydroxyethoxy)‐ or 3‐(3‐hydroxypropoxy)isobenzofuran‐1(3H)‐ones 3 has been developed. Thus, the reaction of 1‐(1,3‐dioxol‐2‐yl)‐ or 1‐(1,3‐dioxan‐2‐yl)‐2‐lithiobenzenes, generated in situ by the treatment of 1‐bromo‐2‐(1,3‐dioxol‐2‐yl)‐ or 1‐bromo‐2‐(1,3‐dioxan‐2‐yl)benzenes 1 with BuLi in THF at ?78°, with (Boc)2O afforded tert‐butyl 2‐(1,3‐dioxol‐2‐yl)‐ or 2‐(1,3‐dioxan‐2‐yl)benzoates 2 , which can subsequently undergo facile lactonization on treatment with CF3COOH (TFA) in CH2Cl2 at 0° to give the desired products in reasonable yields. 相似文献
7.
在水乙醇混合溶剂中,首次得到了2-羰基丙酸水杨酰腙、1,10-菲啰啉与硝酸钆形成的配合物[Gd(C10H9N2O4)(C10H8N2O4)(H2O)3]2·phen·4H2O,并测试了其单晶结构。该配合物属三斜晶系,空间群为P-1。每个配合物分子中有两个九配位的钆的结构单元,每个钆离子与两个三齿配体2-羰基丙酸水杨酰腙(分别以负一价和负二价形式)和三个水分子配位。每个钆单元在空间呈扭曲的单帽四方反棱柱。同时还有一个游离的1,10-菲啰啉存在于晶格中,通过氢键与配位水作用。生物活性试验表明该配合物对三种病原菌有一定的抑菌活性。 相似文献
8.
Vahuni Karapetyan Satenik Mkrtchyan Gnuni Karapetyan Alexander Villinger Ashot Saghiyan Tariel V. Ghochikyan Peter Langer 《Helvetica chimica acta》2011,94(11):2045-2053
(Benzyloxycarbonyl)‐protected 3,4‐benzo‐7‐hydroxy‐2,9‐diazabicyclo[3.3.1]non‐7‐enes were prepared by one‐pot cyclizations of 1,3‐bis(silyl enol ethers) with quinazolines. Subsequent hydrogenation resulted in one‐pot deprotection and rearrangement to give 2‐(2‐aminophenyl)‐2,3‐dihydropyridin‐4(1H)‐ones. 相似文献
9.
Single crystals of [Cu(ATSC)]NH2SO3 ( 1 ) (ATSC –4‐allylthiosemicarbazide) were obtained by electrochemical synthesis using alternating current. Compound ( 1 ) crystallizes in P212121 sp. gr., a = 6.8284(2), b = 9.3054(3), c = 16.1576(11) Å, Z = 4. ATSC moiety acts as tetradentate ligand, chelating two symmetrically related copper atoms. The Cu atom possesses trigonal pyramidal coordination, formed by two sulphur atoms (one of them at the apical position), nitrogen atom and C=C bond. Sulfamate anion is associated via hydrogen bonds. By slow hydrolysis of 1 crystals of [Cu2(ATSC)2]SO4 ( 2 ) were obtained: P 1 sp. gr., a = 9.526(2), b = 12.687(2), c = 14.7340(10) Å, α = 95.119(10), β = 89.903(12), γ = 109.113(14)°, Z = 4. The asymmetric unit of 2 contains two formula units, which are related by pseudosymmetry via a glide plane a. One half of four ATSC molecules act as in 1 , the rest as tridentate ligands, which coordinate the two copper atoms in apical positions with sulfate anions. This Cu–S coordination was to date unknown. The structure of the ATSC ligands contributes to the unexpected competitiveness of C=bond in the coordination sphere of CuI inspite of strong donor atoms. 相似文献
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Biswanath Das Nikhil Chowdhury K. Damodar K. Ravinder Reddy 《Helvetica chimica acta》2007,90(2):340-345
A simple, mild, rapid, and highly efficient method for the conjugate addition of 1H‐indoles to electron‐deficient olefins has been developed using NaHSO4 ? SiO2 as heterogeneous catalyst. The conversion proceeds at room temperature, and the corresponding Michael adducts are formed in good‐to‐excellent yields. 相似文献
11.
Gowravaram Sabitha Rangavajjula Srinivas Peddabuddi Gopal M. Bhikshapathi Jhillu Singh Yadav 《Helvetica chimica acta》2011,94(1):119-121
Bismuth(III) chloride was found to be an efficient catalyst for the transesterification of a variety of β‐keto esters with a wide range of alcohols to afford transesterified products in good to high yields in short reaction times (see Table). 相似文献
12.
The reaction of Gd(ClO4)3·6H2O with 5‐(1H‐tetrazol‐5‐yl)isophthalic acid affords a 3D framework gadolinium coordination polymer, [Gd(C9H3N4O4)(H2O)3·2H2O]n ( 1 ). Its crystal structure belongs to a triclinic system, space group , with a = 7.909(2) Å; b = 8.448(2) Å; c = 10.994(2) Å; α = 102.65(3)°; β = 124.32(2)°; γ = 96.28(3)°; V = 704.5(2) Å3; Z = 2; R1 = 0.0245 for 3225 reflections with I >2σ(I), wR2 = 0.0556. Fluorescent analyses show that compound 1 exhibits purple fluorescence in the solid state at room temperature. 相似文献
13.
The o‐substituted hybrid phenylphosphines, PPh2(o‐C6H4NH2) and PPh2(o‐C6H4OH), could be deprotonated with LDA or n‐BuLi to yield PPh2(o‐C6H4NHLi) and PPh2(o‐C6H4OLi), respectively. When added to a solution of (η5‐C5H5)Fe(CO)2I at room temperature, these two lithiated reagents produce a chelated neutral complex 1 (η5‐C5H5)Fe(CO)[C(O)NH(o‐C6H4)PPh2‐C,P‐η2] for the former and mainly a zwitterionic complex 2 , (η5‐C5H5)Fe+(CO)2[PPh2(o‐C6H4O?)] for the latter. Complex 1 could easily be protonated and then decarbonylated to give 4 [(η5‐C5H5)Fe(CO){NH2(o‐C6H4)PPh2‐N,P‐η2}+]. Complexes 1 and 4‐I have been crystallographically characterized with X‐ray diffraction. 相似文献
14.
A number of alkyltin(IV) paratoluenesulfonates, RnSn(OSO2C6H4CH3‐4)4?n (n = 2, 3; R = C2H5, n‐C3H7, n‐C4H9), have been prepared and IR spectra and solution NMR (1H, 13C, 119Sn) are reported for these compounds, including (n‐C4H9)2Sn(OSO2X)2 (X = CH3 and CF3), the NMR spectra of which have not been reported previously. From the chemical shift δ(119Sn) and the coupling constants 1J(13C, 119Sn) and 2J(1H, 119Sn), the coordination of the tin atom and the geometry of its coordination sphere in solutions of these compounds is suggested. IR spectra of the compounds are very similar to that observed for the paratoluenesulfonate anion in its sodium salt. The studies indicate that diorganotin(IV) paratoluenesulfonates, and the previously reported compounds (n‐C4H9)2Sn(OSO2X)2 (X = CH3 and CF3), contain bridging SO3X groups that yield polymeric structures with hexacoordination around tin and contain non‐linear C? Sn? C bonds. In triorganotin(IV) sulfonates, pentacoordination for tin with a planar SnC3 skeleton and bidentate bridging paratoluenesulfonate anionic groups are suggested by IR and NMR spectral studies. The X‐ray structure shows [(n‐C4H9)2Sn(OSO2C6H4CH3‐4)2·2H2O] to be monomeric containing six‐coordinate tin and crystallizes from methanol–chloroform in monoclinic space group C2/c. The Sn? O (paratoluenesulfonate) bond distance (2.26(2) Å) is indicative of a relatively high degree of ionic character in the metal–anion bonds. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
15.
A clean and efficient tandem oxidative cyclocondensation process is reported for the synthesis of 3,4‐dihydropyrimidin‐2(1H)‐one or ‐thione derivatives from primary aryl alcohols, β‐keto esters, and urea or thiourea in the presence of Al(NO3)3?9 H2O as oxidant catalyst (Scheme, Table 5). 相似文献
16.
Two uranyl sulfate hydrates, (H3O)2[(UO2)2(SO4)3(H2O)] · 7H2O (NDUS) and (H3O)2[(UO2)2(SO4)3(H2O)] · 4H2O (NDUS1), and one uranyl selenate‐selenite [C5H6N][(UO2)(SeO4)(HSeO3)] (NDUSe), were obtained and their crystal structures solved. NDUS and NDUSe result from reactions in highly acidic media in the presence of L ‐cystine at 373 K. NDUS crystallized in a closed vial at 278 K after 5 days and NDUSe in an open beaker at 278 K after 2 weeks. NDUS1 was synthesized from aqueous solution at room temperature over the course of a month. NDUS, NDUS1, and NDUSe crystallize in the monoclinic space group P21/n, a = 15.0249(4) Å,b = 9.9320(2) Å, c = 15.6518(4) Å, β = 112.778(1)°, V = 2153.52(9) Å3,Z = 4, the tetragonal space group P43212, a = 10.6111(2) Å,c = 31.644(1) Å, V = 3563.0(2) Å3, Z = 8, and in the monoclinic space group P21/n, a = 8.993(3) Å, b = 13.399(5) Å, c = 10.640(4) Å,β = 108.230(4)°, V = 1217.7(8) Å3, Z = 4, respectively.The structural units of NDUS and NDUS1 are two‐dimensional uranyl sulfate sheets with a U/S ratio of 2/3. The structural unit of NDUSe is a two‐dimensional uranyl selenate‐selenite sheets with a U/Se ratio of 1/2. In‐situ reaction of the L ‐cystine ligands gives two distinct products for the different acids used here. Where sulfuric acid is used, only H3O+ cations are located in the interlayer space, where they balance the charge of the sheets, whereas where selenic acid is used, interlayer C5H6N+ cations result from the cyclization of the carboxyl groups of L ‐cystine, balancing the charge of the sheets. 相似文献
17.
Synthesis and Crystal Structure of meso-(1,2,3-Tricyclohexyltriphosphane-1,3-diyl)zirconocene(IV), Cp2 (Cp = η5?C5H5, Cy = C6H11) Cp2ZrCl2 reacts with Li(THF)2PHCy (Cy = C6H11) to yield the metallacyclic compound Cp2 1. , The 31P{1H} NMR spectrum of 1 , shows a coupling pattern for an A2X system, indicating the presence of only the meso-forms in solution, which are also present in the solid state. 1 , crystallizes in the monoclinic space group P21/n (No. 14) with a = 12.984(8), b = 9.241(7), c = 23.05(1) Å, β = 93.48(4)°, V = 2760.1 Å3 and four formula units in the unit cell (2718 independent observed reflections, R = 7.3%). The central ZrP3 ring in 1 , is almost planar. The Zr? P bond lengths of 2.618(4) and 2.628(4) Å are nearly identical. 相似文献
18.
(NH3CH2CH2NH2)3[Mo(Ⅴ)O2(O2C6H4)2] (1), (NH3CH2CH2NH2)2.5[Mo(Ⅴ)o.sW(Ⅵ)o.502(O2C6H4)2] (2) and(NH3CH2CH2NH2)2[VC(Ⅵ)O2(O2C6H4)2] (3) were synthesized, structurally characterized by X-ray diffraction analysis, and studied on their interactions with ATP, their DNA cleavage activities and antitumor properties. The redox state of molybdenum was not changed on going from crystal to aqueous solutions in complexes 1 and 2, while tungsten underwent reduction from W(VI) to W(V) in complexes 2 and 3. ATP promoted the oxidation of both molybdenum and tungsten from M(Ⅴ) to M(Ⅵ) and the hydrolysis of catecholate ligands in solution consisting of ATP and the complexes. Complex 1 possesses fairly good activity to DNA cleavage and against tumor S180 in mice, and is more effective than the control drug cyclophosphamide under the identical conditions. However, complexes 2 and 3 exhibited marginal effectiveness. The effectiveness of anti-tumor of the complexes was related positively to their DNA cleavage activities and their hydrolysis of catecholate ligands. 相似文献
19.
Two sulfato CuII complexes [Cu2(bpy)2(H2O)(OH)2(SO4)]· 4H2O ( 1 ) and [Cu(bpy)(H2O)2]SO4 ( 2 ) were synthesized and structurally characterized by single crystal X—ray diffraction. Complex 1 consists of the asymmetric dinuclear [Cu2(bpy)2(H2O)(OH)2(SO4)] complex molecules and hydrogen bonded H2O molecules. Within the dinuclear molecules, the Cu atoms are in square pyramidal geometries, where the equatorial sites are occupied by two N atoms of one bpy ligand and two O atoms of different μ2—OH groups and the apical position by one aqua ligand or one sulfato group. Through intermolecular O—H···O and C—H···O hydrogen bonds and intermolecular π—π stacking interactions, the dinuclear complex molecules are assembled into layers, between which the hydrogen bonded H2O molecules are located. The Cu atoms in 2 are octahedrally coordinated by two N atoms of one bpy ligand and four O atoms of two H2O molecules and two sulfato groups with the sulfato O atoms at the trans positions and are bridged by sulfato groups into 1[Cu(bpy)(H2O)2(SO4)2/2] chains. Through the interchain π—π stacking interactions and interchain C—H···O hydrogen bonds, the resulting chains are assembled into bi—chains, which are further interlinked into layers by O—H···O hydrogen bonds between adjacent bichains. 相似文献
20.
A series of novel 3‐((4‐(t‐butyl)‐2‐(2‐benzylidenehydrazinyl)thiazol‐5‐yl)methyl)quinolin‐2(1H)‐ones ( 7a – 7z ) were designed, synthesized and evaluated for their ability of inhibiting neuraminidase (NA) of in?uenza H1N1 virus. Some compounds displayed moderate influenza NA inhibitory activity. Compound 7l with the scaffold of 2‐(2‐(2‐methoxybenzylidene)hydrazinyl)thiazole was the best one, exhibiting moderate NA inhibitory activity with IC50 of 44.66 µmol/L. Structure‐activity relationship showed that compounds with methoxy or hydroxy groups at the ortho position, fluorine and nitro groups at the meta position and chlorine and bromine groups at the para position of phenyl ring were more active. Docking study indicated that compound 7l has important interactions with some key residues (including Asp151, Glu119, Arg292, Tyr406, and Asn347) and binds to 430‐cavity adjacent to NA active site. 相似文献