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1.
Products of the gas-phase reactions of OH radicals with O,O-diethyl methylphosphonothioate [(C2H5O)2P(S)CH3, DEMPT] and O,O,O-triethyl phosphorothioate [(C2H5O)3PS, TEPT] have been investigated at room temperature and atmospheric pressure of air using in situ atmospheric pressure ionization mass spectrometry (API-MS) and, for the TEPT reaction, gas chromatography and in situ Fourier transform infrared (FT-IR) spectroscopy. Combined with products quantified previously by gas chromatography, the products observed were: from the DEMPT reaction, (C2H5O)2P(O)CH3 (21+/-4% yield) and C2H5OP(S)(CH3)OH or C2H5OP(O)(CH3)SH (presumed to be C2H5OP(O)(CH3)SH by analogy with the TEPT reaction); and from the TEPT reaction, (C2H5O)3PO (54-62% yield), SO2 (67+/-10% yield), CH3CHO (22-40% yield) and, tentatively, (C2H5O)2P(O)SH. The FT-IR analyses showed that the formation yields of HCHO, CO, CO2, peroxyacetyl nitrate [CH3C(O)OONO2], organic nitrates, and acetates from the TEPT reaction were <5%, 3+/-1%, <7%, <2%, 5+/-3%, and 3+/-2%, respectively. Possible reaction mechanisms are discussed.  相似文献   

2.
Phosphorylation of several D-glucose derivatives has been achieved using inorganic monoimido-cyclo-triphosphate (MCTP, Na(3)P(3)O(8)NH) in aqueous solution. In the phosphorylation of D-glucose, D-glucuronic acid, 2-deoxy-D-glucose and D-galactose, 1-O-diphosphoramidophosphono-beta-D-glucose, 1-O-diphosphoramidophosphono-beta-D-glucuronic acid, 1-O-diphosphoramidophosphono-2-deoxy-beta-D-glucose, and 1-O-diphosphoramidophosphono-beta-D-galactose were stereoselectively synthesized with yields of 54, 32, 37 and 46%, respectively. In the case of methyl alpha-D-glucoside, the phosphorylated products were methyl 3-O-diphosphoramidophosphono-alpha-D-glucoside and methyl 4-O-diphosphoramidophosphono-alpha-D-glucoside, and in the case of methyl beta-D-glucoside the products were methyl 2-O-diphosphoramidophosphono-beta-D-glucoside, methyl 3-O-diphosphoramidophosphono-beta-D-glucoside, and methyl 4-O-diphosphoramidophosphono-beta-D-glucoside. For D-mannose and D-allose, several phosphorylated products were obtained and the main products were 1-O-diphosphoramidophosphono-beta-D-aldoses.  相似文献   

3.
本文通过η^5-Bz~5C~5MNa与氧化偶联试剂Fe~2(SO~4)~3/HOAC/H~2O的反应合成了含η^5-五苄基环戊二烯基配体的两个金属-金属单键化合物[η^5-Bz~5C~5(CO)~3M]~2 (1: M=Mo; 2: M=W) , 产率分别为45%和19% . 1 在沸腾的甲苯中可进一步脱碳而以98%的产率生成金属-金属叁键化合物[η^5-Bz~5C~5(CO)~2Mo]~2 (3).1~3的结构均经碳氢分析, IR, ^1H NMR 和MS鉴定. 3的结构尚被单晶X射线衍射分析确证 .  相似文献   

4.
5-Pyrimidylboronic acid and 2-methoxy-5-pyrimidylboronic acid 4 have been synthesised by lithium-halogen exchange reactions on 5-bromopyrimidine and 2-methoxy-5-bromopyrimidine, respectively, followed by reaction with triisopropylborate. Suzuki cross-coupling reactions of 2 and 4 with heteroaryl halides [Na(2)CO(3), Pd(PPh(3))(2)Cl(2), 1,4-dioxane, 95 degrees C] yield heteroarylpyrimidines (heteroaryl = thienyl, quinolyl and pyrimidyl). Two-fold reaction of 2 with 4,6-dichloropyrimidine 12 gave 4,6-bis(5-pyrimidyl)pyrimidine 8(56% yield). Reaction of 4,6-dichloropyrimidine with 2-methoxy-5-pyridylboronic acid gave 4,6-bis(2-methoxy-5-pyridyl)pyrimidine 14 (84% yield). Conversion of into 4,6-bis(2-chloro-5-pyridyl)pyrimidine 15 (63% yield) followed by two-fold Suzuki reaction with 4-tert-butylbenzeneboronic acid gave the penta-arylene derivative 4,6-bis[2-(4-tert-butyl)phenyl-5-pyridyl]pyrimidine 16 (16% yield). Analogous reaction of 12 with 2-methoxy-3-pyridylboronic acid 17 gave 4,6-bis(2-methoxy-3-pyridyl)pyrimidine 18 (64% yield). The X-ray crystal structures of compound 2.0.5H(2)O and compound 18 are reported. The two hydroxyl H atoms in 2 have the usual exo-endo orientation. However, unlike most arylboronic acids, molecule 2 does not form a centrosymmetric hydrogen-bonded dimer. In molecule 18, the pyridine rings form dihedral angles of 39.9 degrees and 22.8 degrees with the central pyrimidine ring.  相似文献   

5.
无水三氯化钕与环戊烷基环戊二烯钠、溴化锂(1:2:1摩尔比)反应,除去不溶物和溶剂后,产物在己烷/四氢呋喃溶剂中冷冻得到兰紫色晶体(C5H9C5H4)3NdBrLi(THF)3(配合物1)。其中心金属Nd3+的配位数为10,以η5与3个环戊二烯基相连,并通过单溴原子桥连锂原子,形成双核结构。该晶体属三斜晶系,P`1空间群。晶体学参数为a=12.048(2)、b=13.498(3)、c=13.831(3);α=104.16(3)、β=104.07(3)、γ=95.96(3); V=2083.3(7)3、Z=2、Dc=1.35Mg/m3、Mr=847.01gmol-1、F(000)=874。无水三氯化钐与环戊烷基环戊二烯钠(1:3)反应,产物在-30oC下的己烷溶剂中结晶得桔红色晶体(C5H9C5H4)3SmTHF(配合物2)。该晶体属正交晶系,Fdd2空间群。晶胞参数a=28.175(5) 、b=46.24(2)、c=9.167(4);V=11943(8)3、Z=16、Dc=1.38Mg/m3、 Mr=622.11 g·mol-1、F(000)=5136。10配位的金属Sm3+与3个环戊二烯基以η5相连,并结合一个四氢呋喃溶剂分子。  相似文献   

6.
通过化学分析、SEM显微分析技术结合RosinRamiler概率统计理论从介观层次研究Na5P3O10CaOH2CO2H2O体系纳米CaCO3的合成反应及其成核和生长过程。结果表明Na5P3O10对CaOH2的碳化反应具有抑制作用。随着Na5P3O10的增加体系中CaCO3的成核速率B0逐渐增大。在Na5P3O10=0ppm时CaCO3结晶的生长由长程扩散和凝聚生长控制Na5P3O10=380.4760.9ppm时前期受短程扩散和界面反应控制、后期受长程扩散控制。Na5P3O10的存在抑制了纳米CaCO3的晶体生长。  相似文献   

7.
鲁晓明  刘顺诚  刘育  卜显和  洪少良 《化学学报》1997,55(10):1009-1018
为研究大环化合物对客体分子的选择性, 合成了通式为[NaL(Et2O)]2Na2Mo8O26的三种新型N-对R苯基氮杂15冠5八钼多酸钠超分子配合物(其中L分别为: N-苯基氮杂15冠5、N-对氯苯基氮杂15冠5和N-对甲苯基氮杂15冠5), 进行了元素分析, 红外光谱与核磁共振等结构参数的表征, 对R基为CH3的标题配合物作了X射线四圆衍射测定, 该晶体属单斜晶系, 空间群为P21/a,a=1.4590(4)nm, b=1.3817(3)nm, c=1.7639(5)nm, β=112.67(2)°, V=3.281(1)nm^3, Mr=2021.3, Dc=2.11g/cm^3,μ=2.37mm^-^1, F(000)=2048, R=0.045和Rw=0.057, 与[Na.(DB18C6)(CH3OH)M6O19和[Na(DB24C8)]2M6O19进行比较,结果表明: 大环化合物不仅对客体金属离子有分子识别性, 而且对与之抗衡的多酸阴离子也具有影响。  相似文献   

8.
The phosphorylation of several D-glucose derivatives has been achieved using inorganic sodium cyclo-triphosphate hexahydrate (P3m), Na3P3O9 x 6H2O, in aqueous solution. In the phosphorylation of D-glucuronic acid, 6-phosphoryl-D-glucose and D-xylose, beta-D-glucuronic acid 1-triphosphate, 6-phosphoryl-beta-D-glucose 1-triphosphate and beta-D-xylose 1-triphosphate were synthesized stereoselectively with maximum yields of 43.5, 32.8 and 41.9%, respectively. In the case of D-glucosamine and 2-deoxy-D-glucose, the main phosphorylated products were assigned to beta-D-glucosamine 1-triphosphate and 2-deoxy-beta-D-glucose 1-triphosphate by 1H-, 13C- and 31P-NMR, and the yields were 13.9 and 13.4%, respectively.  相似文献   

9.
张桂玲  冉靓  罗绪强  曾加 《化学通报》2014,77(6):515-520
设计并合成了两个五员瓜环(Q[5])桥联K+和Na+形成的新型配合物[K(H2O)2Na(H2O)Q[5]](ClO4)2·6H2O(1),[KNaH(H2O)4Q[5]]n(ClO4)3n·3nH2O(2)。利用单晶X射线衍射进行结构测定,结果表明,配合物1中Q[5]起着一个双五齿配体的作用,每个端口的5个羰基氧原子分别和钾离子和钠离子配位,形成分子胶囊;配合物2中每个钾离子分别通过与相邻的2个Q[5]端口的相邻一对羰基氧原子配位,使得配合物形成一维链状结构,同时Q[5]还提供1个羰基氧原子与Na+配位,氢键使得配合物形成三维超分子结构。  相似文献   

10.
Yang W  Lu C  Lin X  Zhuang H 《Inorganic chemistry》2002,41(3):452-454
A novel ESR-silent polyoxomolybdate Na(21)([Na(5)(H(2)O)(14)][Mo(46)O(134)(OH)(10)(mu-CH(3)COO)(4)]).CH(3)COONa.approximately equal to 90H(2)O (3) was simply synthesized in high yield by reducing an acidified aqueous solution of Na(2)MoO(4).2H(2)O and CH(3)COONa.3H(2)O. The structure of 3 is constructed by a 46-member crown-shaped anion, [Na(5)(H(2)O)(14)]within[Mo(V)(20)Mo(VI)(26)O(134)(OH)(10)(mu-CH(3)COO)(4)](21-), 3a, which is built up by three different but related building blocks in a new mode and further connected into layers via Na(+) and hydrogen bonds. Crystal data of compound 3: triclinic space group P(-1); a = 16.4065(3), b = 17.4236(2), c = 20.8247(3) A; alpha= 87.57, beta= 67.9810(10), gamma= 80.6970(10)o; V = 5445.08(14) A(3); Z = 1; D(calcd) = 2.902. Structure solution and refinement are based on 19014 reflections, R = 0.0750.  相似文献   

11.
A lithium gadolinium phosphate crystal, LiGd5P2O13, has been synthesized by a high temperature solution reaction and solved by single-crystal X-ray diffraction data. The structure is monoclinic, space group C2/m, with unit cell parameters a = 18.645(3), b = 5.6257(5), c = 12.014(2) A, beta = 117.55(6)degrees, V = 1117.3(3) A3, and Z = 4. LiGd5P2O13 presents a new structural type and is built up from [Gd5P2O13]- layers and one-dimensional Li chains with an unusual Li-Li distance. The optical properties were investigated in terms of the absorption and emission spectra. Additionally, the calculations of band structure, density of states, dielectric constants, and refractive indexes were performed with the density functional threory method. The obtained results tend to support the experimental data.  相似文献   

12.
The assignment of high-field (18.8 T) (17)O MAS and 3QMAS spectra has been completed by use of first-principles calculations for three crystalline sodium phosphates, Na 3P 3O 9, Na 5P 3O 10, and Na 4P 2O 7. In Na 3P 3O 9, the calculated parameters, quadrupolar constant ( C Q), quadrupolar asymmetry (eta Q), and the isotropic chemical shift (delta cs) correspond to those deduced experimentally, and the calculation is mandatory to achieve a complete assignment. For the sodium tripolyphosphate Na 5P 3O 10, the situation is more complex because of the free rotation of the end-chain phosphate groups. The assignment obtained with ab initio calculations can however be confirmed by the (17)O{ (31)P} MAS-J-HMQC spectrum. Na 4P 2O 7 (17)O MAS and 3QMAS spectra show a complex pattern in agreement with the computed NMR parameters, which indicate that all of the oxygens exhibit very similar values. These results are related to structural data to better understand the influence of the oxygen environment on the NMR parameters. The findings are used to interpret those results observed on a binary sodium phosphate glass.  相似文献   

13.
A family of polyoxometalate compounds based on Preyssler anions and lanthanide cations, K(5)Na(5)[{Pr(4)(H(2)O)(12)(pydc)(4)}{Na(H(2)O)P(5)W(30)O(110)}]·46H(2)O (1, H(2)pydc = pyridine-2,6-dicarboxylic acid), Na(7)[{Pr(4)(H(2)O)(20)(pydc)(2)(Ac)}{Na(H(2)O)P(5)W(30)O(110)}]·23H(2)O (2), and Na(10)H(2) [{Ln(2)(H(2)O)(10)(pydc)(2)}{Na(H(2)O)P(5)W(30)O(110)}]·XH(2)O (Ln = Sm 3, Eu 4, Gd 5; X = 11 for 3 and 5, 13 for 4), have been synthesized and characterized by elemental analysis and single crystal X-ray diffraction. Compound 1 exhibits a two-dimensional honeycomb layer which is built up from unique {Pr(4)} metallacycles and Preyssler anions. Remarkably, the strong involvement of the sodium countercations leads to the formation of a unique three-dimensional open architecture with one-dimensional channels. The 2D grid layer of compound 2 is constructed by the longest currently known rare-earth metal clusters {Pr(8)} and Preyssler anions. Isostructural compounds 3, 4, and 5, obtained by introduction of the intermediate lanthanide ions into the above reaction system, exhibit bisupporting [{Ln(2)(H(2)O)(10)(pydc)(2)}{Na(H(2)O)P(5)W(30)O(110)}](12-) polyoxometalate cluster structures. The magnetic properties of compounds 1 and 2 and the luminescent properties of compounds 3 and 4 are discussed in this paper.  相似文献   

14.
以5-取代吲哚为原料,经维尔斯迈尔-哈克反应制得5-取代吲哚-3-甲醛(2a~2e); 2a~2e在DMF催化下,与盐酸羟胺反应制得5-取代吲哚-3-甲腈(3a~3e); 3a~3e在H2O2和NaOH溶液中水解合成了5-取代吲哚-3-甲酰胺(4a~4e, 4b~4e为新化合物),产率62.0%~75.0%,其结构经1H NMR, 13C NMR和ESI-MS表征。  相似文献   

15.
Two new mixed-metal tellurites, Na1.4Nb3Te4.9O18 and NaNb3Te4O16, have been synthesized by standard solid-state techniques using Na2CO3, Nb2O5, and TeO2 as reagents. The structures of Na1.4Nb3Te4.9O18 and NaNb3Te4O16 were determined by single-crystal X-ray diffraction. Both of the materials exhibit three-dimensional structures composed of NbO6 octahedra, TeO4, and TeO3 polyhedra. The Nb5+ and Te4+ cations are in asymmetric coordination environments attributable to second-order Jahn-Teller (SOJT) effects. The Nb5+ cations undergo an intraoctahedral distortion toward a corner (local C4 direction), whereas the Te4+ cations are in distorted environments owing to their nonbonded electron pair. Infrared and Raman spectroscopy, UV-vis diffuse reflectance spectroscopy, thermogravimetric analysis, and dielectric measurements were also performed on the reported materials. Crystal data: Na1.4Nb3Te4.9O18, monoclinic, space group C2/m (No. 12), with a = 32.377(5) A, b = 7.4541(11) A, c = 6.5649(9) A, beta = 95.636(5) degrees, V = 1576.7(4) A3, and Z = 4; NaNb3Te4O16, monoclinic, space group P2(1)/m (No. 11), with a = 6.6126(13) A, b = 7.4738(15) A, c = 14.034(3) A, beta = 102.98(3) degrees, V = 675.9(3) A3, and Z = 2.  相似文献   

16.
The hetero-metal clusters [h5-C5H4C(O)CH2CH2C(O)OCH3]FeCoM(m3-S)(CO)8 (M = Mo 1, M = W 2) were prepared by thermal reactions of FeCo2(CO)9(m3-S) with metal exchange reagent [h5-C5H4C(O)CH2CH2C(O)OCH3]M(CO)3Na (M = Mo or W) in THF. Cluster 1 reacted with 2,4-dinitrophenylhydrazine at room temperature to yield the cluster hydrazone derivative (m3-S)CoFeMo(CO)8[h5-C5H4C(NR)Me] [R = NHC6H3-2,4-(NO2)2] 3. All the compounds were characterized by elemental analyses, IR and NMR spectra. Cluster 1 was determined by single crystal X-ray diffraction. Crystal data: C18H11O11SCoFeMo, Mr = 646.05, triclinic, space group P_1, a = 8.148(2), b = 10.685(3), c = 13.410(4) ?, a = 100.077(5), b = 102.452(5), g = 91.108(6)°, V = 1120.4(5) ?3, Z = 2, Dc = 1.915 g/cm3, F(000) = 636, m = 2.071 mm-1, the final R = 0.0378 and wR = 0.0968 for 5074 observations with (I > 2s(I)).  相似文献   

17.
Phosphonate and phosphonic acid functionalized phosphine complexes of platinum(II) were prepared via direct reaction of the ligands with K2PtCl4 in water. Either cis or trans geometries were found depending on the nature of the ligand. The crystal structure of P(3-C6H4PO3H2)3.2H2O (6b) (triclinic, P1, a = 8.3501(6) A, b = 10.1907(6) A, c = 14.6529(14) A, alpha = 94.177(6) degrees, beta = 105.885(6) degrees, gamma = 108.784(5) degrees, Z = 2) shows a layered arrangement of the phosphonic acid. The phosphonodiamide complex cis-[PtCl2(P[4-C6H4PO[N(CH3]2]]3)2].3H2O (10) was synthesized in 89% yield and hydrolyzed to the phosphonic acid complex using dilute HCl. Aqueous phase and silica gel supported catalytic phosphonylation of phenyl triflate using palladium phosphine complexes was achieved. A molybdenum complex, Mo(CO)5[P3-C6H4PO3H2)3] (11), was synthesized in situ and grafted to an alumina surface. XPS, RBS, and AFM studies confirm the formation of a monolayer of 11 on the alumina surface.  相似文献   

18.
Monoclinic Cu3V2O7(OH)2·2H2O(copper polyvanadate) hollow spheres were prepared with Na2V6O16·3H2O nanobelts as V-precursor by hydrothermal method.The purity and structure of the products were characterized by X-ray powder diffraction(XRD),Fourier transform infrared(FTIR) spectroscopy,Raman spectroscopy,thermogravimetric analysis(TGA) and X-ray photoelecton spectroscopy(XPS).The morphology and size were observed by scanning electron microscopy(SEM).We found that the Kagomé staircase-structural copper polyvanadate hollow spheres with an average diameter of 7 μm could be easily synthesized via the reaction of Na2V6O16·3H2O nanobelts with sufficient copper sulfate.The dielectric property of the copper polyvanadate demonstrates that dielectric loss hardly changes when the frequency of applied electric field is higher than 100 kHz.The formation process of the hollow spheres is discussed in detail by the observation of a series of products prepared for different reaction time.  相似文献   

19.
一个新的铈砷钨酸盐大阴离子[As4W40O140Ce(H2O)5]^25-   总被引:4,自引:0,他引:4  
薛岗林 《化学学报》2001,59(9):1519-1521
合成了一新的铈砷钨酸盐[As4W40C140Ce(H2O)5]Na25·63H2O,用X射线单晶衍射法及元素分析确定了其结构。其晶胞参数为:a=3.1252(8)nm,b=2.2656(6)nm,c=1.3973(9)nm,α=β=γ90°,V=9.893(7)nm^3,空间群P21/m21/m2/n。在聚阴离子[As4W40O140Ce(H2O)5]^25-中,四个桥连WO6八面体通过相互共享两个顺式氧串联四个B-α-(AsW9O33)^9-形成环配体(As4W40O140)^28-的基本框架,四个B-α-(AsW9O33)^9-并不处在一个平面上,而是上下交错分布的。中心离子Ce(Ⅲ)未完全填充在(As4W40O140)^28-中具有八齿配位能力的S1洞穴中,而是四个桥连的WO6八面体各提供一个端基氧向Ce(Ⅲ)配位,另有五个水分子向Ce(Ⅲ)配位,Ce(Ⅲ)离子的配位数为9,该离具有C2v对称性。  相似文献   

20.
The palladium-substituted tungstoantimonate(III) [Cs(2)Na(H(2)O)(10)Pd(3)(alpha-SbW(9)O(33))(2)](9-) (1) has been synthesized and characterized by IR, elemental analysis, and electrochemistry. Single-crystal X-ray analysis was carried out on Cs(3)KNa(5)[Cs(2)Na(H(2)O)(10)Pd(3)(SbW(9)O(33))(2)].16.5H(2)O, which crystallizes in the monoclinic system, space group P2(1)/m, with a = 13.3963(13) A, b = 19.5970(19) A, c = 18.1723(17) A, beta = 100.416(2) degrees, and Z = 2. Polyanion 1 represents the first structurally characterized palladium(II)-substituted polyoxometalate. The title polyoxoanion consists of two (alpha-Sb(III)W(9)O(33)) Keggin moieties linked via three Pd(2+) ions leading to a sandwich-type structure. The palladium centers are equivalent, and they are coordinated in a square-planar fashion. The central belt of 1 contains also one sodium and two cesium ions which reduces the symmetry of the polyanion to C(2)(v)(). Polyanion 1 was synthesized in good yield by reaction of Pd(CH(3)COO)(2) with Na(9)[SbW(9)O(33)] in aqueous acidic medium (pH 4.8). A cyclic voltammetry study of polyanion 1 in a pH 5 medium gives essentially the same characteristics as those observed for the deposition of Pd(0) on the glassy carbon electrode surface from Pd(2+) solutions. The film thickness increases with the number of potential cycles or the duration of potentiostatic electrolysis. The particularly sharp hydrogen sorption/desorption pattern indicates the excellent quality of the Pd(0) deposit from polyanion 1.  相似文献   

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