含吡啶环系西佛碱大环配合物和氮杂大环自由配体的合成

2, 6-二羟甲基吡啶(1)经活性MnO~2氧化得到2, 6-二甲酰基吡啶(2)。邻硝基苯酚与N-取代的二(氯乙基)胺在DMF溶液中反应, 得到N-取代的1, 5-二(邻硝基苯氧基)-3-氮杂戊烷(3a～3c), 再经水合肼/Raney Ni还原, 获得N-取代的1, 5-二(邻氨基苯氧基)-3-氮杂戊烷(4a～4c)。利用Ba^2^+作为模板离子, (2)分别与(4a～4c)反应, 合成了一类新的含吡啶环系西佛碱大环配合物I-III, 配合物I、III与NaBH~4的乙醇溶液还原解络, 得到氮杂大环自由配体IV和V。所有西佛碱大环配合物和氮杂大环自由配体均经元素分析、IR、^1H NMR、MS等证实了它们的结构和组成。     

分子内1,3-偶极环加成反应的研究 I.4-取代苯基(N-4-戊烯基)硝酮的热化学反应性能及其区域选择性

合成并研究了4-取代苯基(N-4-戊烯基)硝酮的热化学反应[取代基为OCH~3(1a),H(1b),Br(1c),NO~2(1d)].环加成反应活性顺序为NO~2>Br>H>OHC~3.反应具有区域选择性,加成物8-(4-取代苯基)-2-氧杂-1-氮杂双环[3.2.1]辛烷(2)和2-(4-取代苯基)-8-氧杂-1-氮杂双环[3.2.1]辛烷(3)的比约为2:1. 1,3-偶极硝酮(1a-1d)可部分转变为双键迁移产物(4a-4d).     

3-硝基-1，2，4-三唑-5-酮二甲胺盐（CH3）2NH2^＋C2N4O3H^-的合成、晶体结构和量子化学研究

利用3-硝基-1，2，4-三唑-5-酮(NTO)的乙醇溶液与二甲胺的水溶液合成了 NTO的二甲胺盐(CH_3)_2NH_2~+C_2N_4O_3H~-，在二甲基甲酰胺(DMF)和甲醇的混合 溶剂（体积比为1:5）中培养出单晶。通过X射线单晶结构分析法测定分子结构和晶 体结构，晶体属单斜晶系，空间群为P2(1)/c，晶胞参数为：a=0.7116(1)nm, b=0. 8735(2) nm, c=1.3160(3)nm, β=101.12(2) °,V=0.8026(3)nm~3, D_c=1.450 g/cm~3, Z=4, F(000)=368。采取HF/6-31+G(d)和MP2/6-31+G(d)以及B3LYP/6- 31+G(d)方法对标题化合物进行了几何全优化，并对其成键情况、原子净电荷分布 及化合物的稳定性进行了分析。     

2-叠氮基-1,1-二硝基乙基取代苯衍生物的合成

详细研究了2-叠氮基-1,1-二硝基乙基取代苯衍生物的合成方法。由苯基二硝基甲烷钾盐经羟甲基化，磺酰酯化和叠氮化得到目标化合物：3-硝基-(2-叠氮基-1,1-二硝基乙基)苯(4b)，4-硝基-(2-叠氮基-1,1-二硝基乙基)苯(4c)，m-二(2-叠氮基-1,1-二硝基乙基)苯(10)和p-二(2-叠氮基-1,1-二硝基乙基)苯(15)。     

3-三氯锡基丙酸酯及其配合物的合成与结构表征

合成了4个新的3-三氯锡基丙酸酯Cl3SnCH2CH2COOR(R=环戊基，1；环己基，2 ；环戊甲基，3；环己甲基，4)，并通过其与二丁基亚砜(L^1)、2，2’-联吡啶 (L^2)、1，10-菲咯啉(L^3)的低热固相反应合成了6个相应的配合物 Cl3SnCH2CH2COOR·L(L=L^1,a;L^2,b;L^3,c).利用元素分析、红外光谱、核磁共振 对其结构进行了表征，并通过X射线单晶衍射测定了1和2的晶体结构，二者均为具 有分子内羰基氧原子配位的畸变三角双锥结构．1属于单斜品系，空间群P21/c, a=0.9842(2)nm,b=1.0923(8)nm,c=1.23948(11)nm,β=93.894(15)°,V=1.3294(4) nm^3,Mr=366.23,Z=4.2属于单斜晶系，空间群P21/c,a=1.04443(9)nm,b=1.04823 (7)nm,c=1.28113(9)nm,β=90.953(8)°,V=1.40239(19)nm^3,Mr=380.25,Z=4.     

重氮萘酮在环醚中热解反应研究

三种带有不同取代基的重氮萘酮(la～1c)在THF和二氧六环中加热分解给出不同的产物。1-重氮-4-萘酮(1a)的热解产物主要是重氮萘酮热解后产生的烯酮卡宾(2a)与环醚开环后形成的聚合物;3-甲基-1-重氮-4-萘酮(1b)的热解产物比较复杂,除冠醚类产物之外,还有烯酮卡宾对四氢呋喃和二氧六环的C-H键的插入反应产物、螺环化合物、2-甲基萘酚以及难以分离的聚合物;3-硝基-1-重氮-4-萘酮(1c)的热解产物主要是聚合物,此外还有少量C－H键的插入反应产物和2-硝基萘酚。对重氮萘酮热解反应的机理作了讨论。     

酰氨基硫脲及相关杂环衍生物的研究XXIX: 2-(3'-溴苯胺基)-5-[5'-氨基-1'-(4"-氯苯基)-1',2',3'-三唑-4'-基]-1,3,4-噻二唑的晶体结构

经1-[5'-氨基-1'-(4"-氯苯基)-1',2',3'-三唑-4'-甲酰基]-4-(3'-溴苯基)-3-氨基硫脲在浓硫酸作用下制得2-(3'-溴苯胺基)-5-[5'-氨基-1'-(4"-氯苯基)-1',2',3'-三唑-4'-基]-1,3,4-噻二唑化合物。该化合物的晶体结构经X射线衍射分析确定, 化合物属三斜晶系, P1空间群, a=1.1784(2), b=1.4455(2),c=1.1353(1)nm; α=100.68(1), β=109.50(1), γ=79.89(1)°; V=1.7779nm^3; 分子式C~1~6H~1~1BrClN~7S, Mr=448.75; Dc=1.673g/cm^3, Z=4,μ=58.16cm^-^1, 最终偏离因子R=0.084, Rw=0.086。分析化合物的键长, 键角数据表明, 该分子具有离域π键结构。     

酰氨基硫脲及相关杂环衍生物的研究XXIX: 2-(3'-溴苯胺基)-5-[5'-氨基-1'-(4"-氯苯基)-1',2',3'-三唑-4'-基]-1,3,4-噻二唑的晶体结构

经1-[5'-氨基-1'-(4"-氯苯基)-1',2',3'-三唑-4'-甲酰基]-4-(3'-溴苯基)-3-氨基硫脲在浓硫酸作用下制得2-(3'-溴苯胺基)-5-[5'-氨基-1'-(4"-氯苯基)-1',2',3'-三唑-4'-基]-1,3,4-噻二唑化合物。该化合物的晶体结构经X射线衍射分析确定, 化合物属三斜晶系, P1空间群, a=1.1784(2), b=1.4455(2),c=1.1353(1)nm; α=100.68(1), β=109.50(1), γ=79.89(1)°; V=1.7779nm^3; 分子式C~1~6H~1~1BrClN~7S, Mr=448.75; Dc=1.673g/cm^3, Z=4,μ=58.16cm^-^1, 最终偏离因子R=0.084, Rw=0.086。分析化合物的键长, 键角数据表明, 该分子具有离域π键结构。     

1,1'-(六甲基三硅撑)双环戊二烯基二(对氯苯氧基)钛的合成及晶体结构

以1,3-二氯六甲基三硅烷相继与环戊二烯基钠、正丁基锂和四氯化钛作用合成了1,1'-(六甲基三硅撑)双环戊二烯基二氯化钛(1),1在氨基钠的存在下与对氯苯酚作用制得题目化合物(2)。通过元素分析、^1HNMR和MS鉴定了1与2的结构,并对2进行X射线结构分析确证了其结构。2的晶体属单斜晶系的P21/c空间群。晶胞参数:a=1.0746(3),b=2.4865(7),c=1.2568(2)nm; β=113.42(2)°;V=3.08137nm^3;Z=4,D0=1.305g·cm^-3。化合物中三个硅原子的桥链发生明显扭曲。通过氧原子中心原钛与苯环发生共轭,使整个分子形成共轭体系。     

三环己基羧酸锡的分子结构和晶体结构

用单晶X射线衍射技术测定了三个三环己基羧酸锡化合物—三环己基丁酸锡(1), 三环己基-间氯代苯甲酸锡(2), 三环己基-间溴代苯甲酸锡(3)的分子和晶体结构. 三种化合物均属正交晶系, 空间群分别为P212121(1), Pnaa(2), Pnaa(3). 1的晶胞参数为:a=9.963(2), b=11.004(3), c=20.144(6)埃, Z=4. 2的晶胞参数为: a=8.135(2),b=16.716(3), c=36.426(6)埃, Z=8. 3的昌胞参数为: a=8.165(1), b=16.714(3),c=36.710(4)埃, Z=8. 在1的晶体中, 锡原子呈五配位的三角双锥构型. 桥联的羧基使其结构成为含有两种不同Sn-O键(2.198(4)和2.427(3)埃)的线型聚合物. 2和3的晶体则是由孤立的分子所组成. 在每个分子中, 四配位的锡原子呈畸变的四面体构型, 羧基不能象在化合物1中那样在锡原子之间成桥, 可能主要是由于环己基与卤代苯甲酸根之间的空间位阻效应所致.     

Hydrothermal and solid-state transformation of ruthenium-supported Keggin-type heteropolytungstates [XW11O39{Ru(II)(benzene)(H2O)}]n- (X = P (n = 5), Si (n = 6), Ge (n = 6)) to ruthenium-substituted Keggin-type heteropolytungstates

A new pathway for the preparation of mono-ruthenium (Ru)(iii)-substituted Keggin-type heteropolytungstates with an aqua ligand, [PW(11)O(39)Ru(iii)(H(2)O)](4-) (1a), [SiW(11)O(39)Ru(iii)(H(2)O)](5-) (1b) and [GeW(11)O(39)Ru(iii)(H(2)O)](5-) (1c), using [Ru(ii)(benzene)Cl(2)](2) as a Ru source was described. Compounds 1a-1c were prepared by reacting [XW(11)O(39)](n-) (X = P, Si and Ge) with [Ru(ii)(benzene)Cl(2)](2) under hydrothermal condition and were isolated as caesium salts. Ru(benzene)-supported heteropolytungstates, [PW(11)O(39){Ru(ii)(benzene)(H(2)O)}](5-) (2a), [SiW(11)O(39){Ru(ii)(benzene)(H(2)O)}](6-) (2b) and [GeW(11)O(39){Ru(ii)(benzene)(H(2)O)}](6-) (2c), were first produced in the reaction media, and then transformed to 1a, 1b and 1c, respectively, under hydrothermal conditions. Calcination of Ru(benzene)-supported heteropolytungstates, 2a, 2b and 2c, in the solid state produced mixtures of 1a, 1b and 1c with CO (carbon monoxide)-coordinated complexes, [PW(11)O(39)Ru(ii)(CO)](5-) (4a), [SiW(11)O(39)Ru(ii)(CO)](6-) (4b) and [GeW(11)O(39)Ru(ii)(CO)](6-) (4c), respectively. From comparison of their catalytic activities in water oxidation reaction, it was indicated that ruthenium should be incorporated in the heteropolytungstate in order to promote catalytic activity.     

Computational study on the reactions of H2O2 on TiO2 anatase (101) and rutile (110) surfaces

This study investigates the adsorption and reactions of H(2)O(2) on TiO(2) anatase (101) and rutile (110) surfaces by first-principles calculations based on the density functional theory in conjunction with the projected augmented wave approach, using PW91, PBE, and revPBE functionals. Adsorption mechanisms of H(2)O(2) and its fragments on both surfaces are analyzed. It is found that H(2)O(2) , H(2)O, and HO preferentially adsorb at the Ti(5c) site, meanwhile HOO, O, and H preferentially adsorb at the (O(2c))(Ti(5c)), (Ti(5c))(2), and O(2c) sites, respectively. Potential energy profiles of the adsorption processes on both surfaces have been constructed using the nudged elastic band method. The two restructured surfaces, the 1/3 ML oxygen covered TiO(2) and the hydroxylated TiO(2), are produced with the H(2)O(2) dehydration and deoxidation, respectively. The formation of main products, H(2)O(g) and the 1/3 ML oxygen covered TiO(2) surface, is exothermic by 2.8 and 5.0 kcal/mol, requiring energy barriers of 0.8 and 1.1 kcal/mol on the rutile (110) and anatase (101) surface, respectively. The rate constants for the H(2)O(2) dehydration processes have been predicted to be 6.65 × 10(-27) T(4.38) exp(-0.14 kcal mol(-1)/RT) and 3.18 × 10(-23) T(5.60) exp(-2.92 kcal mol(-1)/RT) respectively, in units of cm(3) molecule(-1) s(-1).     

A reinvestigation of the kinetics and the mechanism of the CH3C(O)O2 + HO2 reaction using both experimental and theoretical approaches

The kinetics and the mechanism of the reaction CH(3)C(O)O(2)+ HO(2) were reinvestigated at room temperature using two complementary approaches: one experimental, using flash photolysis/UV absorption technique and one theoretical, with quantum chemistry calculations performed using the density functional theory (DFT) method with the three-parameter hybrid functional B3LYP associated with the 6-31G(d,p) basis set. According to a recent paper reported by Hasson et al., [J. Phys. Chem., 2004, 108, 5979-5989] this reaction may proceed by three different channels: CH(3)C(O)O(2)+ HO(2)--> CH(3)C(O)OOH + O(2) (1a); CH(3)C(O)O(2)+ HO(2)--> CH(3)C(O)OH + O(3) (1b); CH(3)C(O)O(2)+ HO(2)--> CH(3)C(O)O + OH + O(2) (1c). In experiments, CH(3)C(O)O(2) and HO(2) radicals were generated using Cl-initiated oxidation of acetaldehyde and methanol, respectively, in the presence of oxygen. The addition of amounts of benzene in the system, forming hydroxycyclohexadienyl radicals in the presence of OH, allowed us to answer that channel (1c) is <10%. The rate constant k(1) of reaction (1) has been finally measured at (1.50 +/- 0.08) x 10(-11) cm(3) molecule(-1) s(-1) at 298 K, after having considered the combination of all the possible values for the branching ratios k(1a)/k(1,)k(1b)/k(1,)k(1c)/k(1) and has been compared to previous measurements. The branching ratio k(1b)/k(1), determined by measuring ozone in situ, was found to be equal to (20 +/- 1)%, a value consistent with the previous values reported in the literature. DFT calculations show that channel (1c) is also of minor importance: it was deduced unambiguously that the formation of CH(3)C(O)OOH + O(2) (X (3)Sigma(-)(g)) is the dominant product channel, followed by the second channel (1b) leading to CH(3)C(O)OH and singlet O(3) and, much less importantly, channel (1c) which corresponds to OH formation. These conclusions give a reliable explanation of the experimental observations of this work. In conclusion, the present study demonstrates that the CH(3)C(O)O(2)+ HO(2) is still predominantly a radical chain termination reaction in the tropospheric ozone chain formation processes.     

Synthesis and structure of tetranuclear orthometallated Pd(II) complexes derived from bis-iminophosphoranes

The reaction of Pd(OAc)2 with bis-iminophosphoranes Ph3P=NCH2CH2CH2N=PPh3 (1a), [C6H4(C(O)N=PPh3)2-1,3] (1b) and [C6H4(C(O)N=PPh3)2-1,2] (1c), gives the orthopalladated tetranuclear complexes [{Pd(mu-Cl){C6H4(PPh2=NCH2-kappa-C,N)-2}}2CH2]2 (2a) [{Pd(mu-OAc){C6H4(PPh2=NC(O)-kappa-C,N)-2}}2C6H4-1',3']2 (2b) and [{Pd(mu-OAc){C6H4(PPh2=NC(O)-kappa-C,N)-2}}2C6H4-1',2']2 (2c). The reaction takes place in CH2Cl2 for 1a, but must be performed in glacial acetic acid for 1b and 1c. The process implies in all cases the activation of a C-H bond on a Ph ring of the phosphonium group, with concomitant formation of endo complexes. This is the expected behaviour for 1a, but for 1b and 1c reverses the exo orientation observed in other ketostabilized iminophosphoranes. The influence of the solvent in the orientation of the reaction is discussed. The dinuclear acetylacetonate complexes [{Pd(acac-O,O'){C6H4(PPh2=NCH2-kappa-C,N)-2}}2CH2] (3a), [{Pd(acac-O,O'){C6H4(PPh2=NC(O)-kappa-C,N)-2}}2C6H4-1',3'] (3b) and [{Pd(acac-O,O'){C6H4(PPh2=NC(O)-kappa-C,N)-2}}2C6H4-1',2'] (3c) have been obtained from the halide-bridging tetranuclear derivatives. The X-ray crystal structure of [3c.4CHCl3] is also reported.     

An Ab Initio Study of N_2O Decomposition on MgO Catalyst

Nl0isalwaysusedasoxidantinalotofoxidativecatalyticprocesses,suchastheoxidativecouplingofmethane(0CM),oxidativedehydr0genationofalkanesands0on,becauseitdecomPosestoprovideOadspeciesonmetal0xidecatalystsandleadstothespecificoxidativeselectivity.Forexample,itwasf0undthatf0rOCMreacti0nonMgOandLougOcatalystS,thereactiontemPeraturerequiredislowerwhenoneusesN20asoxidantthanusing0,'.TheunderstandingofN20dec0mposihon0nmetal0xidecatalystsandthepropertiesofthereIevant0adspeciesshouldbeagoodstarting…     

Synthesis and Characterization of Two Mononuclear Mn~Ⅲ Compounds with Mixed Schiff Base Ligands

Two mononuclear Mn compounds of Mn III (salen)(L 1) and Mn III (salen)(L 2) (H 2 salen=N,N-ethylenebis-(salicylideneaminato),L 1=4-(2-hydroxybenzylideneamino)benzoic acid and L 2=4-(2-hydroxybenzylideneamino)-2-hydroxybenzoic acid) have been prepared and characterized by X-ray crystallography.Both compounds crystallize in the monoclinic system,space group P2 1 /c with a=14.351(4),b=14.955(3),c=11.869(3) and β=91.529(3)° for 1;and those for 2:a=14.439(9),b=15.217(9),c=11.660(7) and β=91.648(1)°.The compounds have similar structures,in which the Mn III center adopts a distorted square-pyramidal geometry with the basal plane constructed by two N and two O atoms from the salen ligand and the apical position occupied by the carboxylate O atom from L 1 or L 2 ligand.The voltammetric behavior of the compounds is examined,which shows quasi-reversible one-electron reduction of Mn(Ⅲ) to Mn(Ⅱ).The reduction potentials of both compounds fall between-0.33 V [E 0 (O 2 /O 2 ·)] and 0.65 V [E 0 (1 O 2 /O 2 ·)],which suggest that 1 and 2 could be potential mimics of Mn-SOD.     

Polyoxometalate-supported transition metal complexes and their charge complementarity: synthesis and characterization of [M(OH)6Mo6O18[Cu(Phen)(H2O)2]2][M(OH)6Mo6O18[Cu(Phen)(H2O)Cl]2].5H2O (M = Al(+, Cr3+)

Two Anderson-type heteropolyanion-supported copper phenanthroline complexes, [Al(OH)6Mo6O18[Cu(phen)(H2O)2]2]1+ (1c) and [Al(OH)6Mo6O18[Cu(phen)(H2O)Cl]2]1- (1a) complement their charges in one of the title compounds [Al(OH)6Mo6O18[Cu(phen)(H2O)2]2][Al(OH)6Mo6O18[Cu(phen)(H2O)Cl]2].5H2O [1c][1a].5 H2O 1. Similar charge complementarity exists in the chromium analogue, [Cr(OH)6Mo6O18[Cu(phen)(H2O)2]2][Cr(OH)6Mo6O18[Cu(phen)(H2O)Cl]2].5 H2O [2c][2a].5 H2O 2. The chloride coordination to copper centers of 1a and 2a makes the charge difference. In both compounds, the geometries around copper centers are distorted square pyramidal and those around aluminum/chromium centers are distorted octahedral. Three lattice waters, from the formation of intermolecular O-H.....O hydrogen bonds, have been shown to self-assemble into an "acyclic water trimer" in the crystals of both 1 and 2. The title compounds have been synthesized in a simple one pot aqueous wet-synthesis consisting of aluminum/chromium chloride, sodium molybdate, copper nitrate, phenanthroline, and hydrochloric acid, and characterized by elemental analyses, EDAX, IR, diffuse reflectance, EPR, TGA, and single-crystal X-ray diffraction. Both compounds crystallize in the triclinic space group P. Crystal data for 1: a = 10.7618(6), b = 15.0238(8), c = 15.6648(8) angstroms, alpha = 65.4570(10), beta = 83.4420(10), gamma = 71.3230(10), V = 2182.1(2) angstroms3. Crystal data for 2: a = 10.8867(5), b = 15.2504(7), c = 15.7022(7) angstroms, alpha = 64.9850(10), beta = 83.0430(10), gamma = 71.1570(10), V = 2235.47(18) angstroms3. In the electronic reflectance spectra, compounds 1 and 2 exhibit a broad d-d band at approximately 700 nm, which is a considerable shift with respect to the value of 650-660 nm for a square-pyramidal [Cu(phen)2L] complex, indicating the coordination of [M(OH)6Mo6O18]3- POM anions (as a ligand) to the monophenanthroline copper complexes to form POM-supported copper complexes 1c, 1a, 2c, and 2a. The ESR spectrum of compound 1 shows a typical axial signal for a Cu2+ (d9) system, and that of compound 2, containing both chromium(III) and copper(II) ions, may reveal a zero-field-splitting of the central Cr3+ ion of the Anderson anion, [Cr(OH)6Mo6O18]3-, with an intense peak for the Cu2+ ion.     

Phosphite copper(I) trifluoroacetates [((RO)3P)mCuO2CCF3] (m = 1, 2, 3): synthesis, solid state structures and their potential use as CVD precursors

Metal-organics [((RO)(3)P)(m)CuO(2)CCF(3)] (R = CH(3): 11a, m = 1; 11b, m = 2; 11c, m = 3. R = CH(2)CH(3): 12a, m = 1; 12b, m = 2; 12c, m = 3. R = CH(2)CF(3): 13a, m = 1; 13b, m = 2; 13c, m = 3) are either accessible by the reaction of [((RO)(3)P)(m)CuCl] (R = CH(3): 5a, m = 1; 5b, m = 2; 5c, m = 3. R = CH(2)CH(3): 6a, m = 1; 6b, m = 2; 6c, m = 3) with [KO(2)CCF(3)] (7), or treatment of [Cu(2)O] (8) with HO(2)CCF(3) (9) and P(OR)(3) (2, R = CH(3); 3, R = CH(2)CH(3); 4, R = CH(2)CF(3)). (31)P{(1)H} NMR spectra [((CH(3)O)(3)P)(m)CuO(2)CCF(3)] (m = 1, 1.5, 2, 2.5, 3, 3.5, and 4) have been studied at 25 and -80 °C showing phosphite ligand exchange in solution. The molecular structures of 11a and 13a-13c in the solid state are reported. Complexes 11a and 13a are tetramers featuring μ-η(2)(1κO:2κO')- and μ(3)-η(2)(1κO:2κO':3κO')-(11a) or μ(3)-η(2)(1κO:2κO':3κO')-bonded O(2)CCF(3) ligands (13a) with the Cu(I) ions being part of CuPO(2) and CuPO(3) units (11a), while in 13a solely a CuPO(3) moiety is present. Skeletal isomerism of 11a vs. 13a is discussed. Compound 13b is dimeric ({CuP(2)O(2)}(2)) with pseudo-tetrahedral Cu environments and μ-η(2)(1κO:2κO')O(2)CCF(3) functionalities. In monomeric 13c the O(2)CCF(3) ligand is η(1)(κO)-bonded to a tetra-coordinated Cu(i) ion. The thermal solid state properties of 11, 12 and 13 were studied by Thermo Gravimetry (TG). These complexes decompose by phosphite elimination, decarboxylation and dealkylation. Hot-wall Chemical Vapour Deposition (CVD) experiments were carried out at 380 °C using 11c as precursor for the deposition of copper onto pieces of TiN-coated oxidized silicon substrates. Copper layers of high purity were obtained with grain sizes between 200-1200 nm.     

Sandwich-type silicotungstates: structure and magnetic properties of the dimeric polyoxoanions[[SiM2W9O34(H2O)]2]12- (M = Mn2+, Cu2+, Zn2+)

The novel dimeric silicotungstates [[SiM2W9O34(H2O)]2]12- (M = Mn2+, Cu2+, Zn2+) have been synthesized and characterized by IR spectroscopy, elemental analysis, and magnetic measurements. X-ray single-crystal analyses were carried out on K4Na6Mn[[SiMn2W9O34(H2O)]2].33H2O (1), which crystallizes in the triclinic system, space group P1, with a = 12.2376(7) A, b = 13.6764(8) A, c = 15.6177(9) A, alpha = 70.2860(10) degrees, beta = 79.9150(10) degrees, gamma = 70.2760(10) degrees, and Z = 1; K3Na5[[SiCu2W9O34(H2O)]2].26H2O (2) crystallizes in the triclinic system, space group P1, with a = 11.4271(12) A, b = 12.5956(13) A, c = 15.3223(16) A, alpha = 80.456(2)degrees, beta = 76.383(2) degrees, gamma = 76.968(2) degrees, and Z = 1; K4Na6[[SiZn2W9O34(H2O)]2].34H2O (3) crystallizes also in the triclinic system, space group P1, with a = 12.2596(14) A, b = 13.2555(15) A, c = 16.2892(18) A, alpha = 96.431(2) degrees, beta = 100.944(2) degrees, gamma = 110.404(2) degrees, and Z = 1. The polyanions consist of two lacunary B-alpha-[SiW9O34]10- Keggin moieties linked via a rhomblike M4O16 (M = Mn, Cu, Zn) group leading to a sandwich-type structure. Magnetic measurements show that the central Mn4 unit in 1 exhibits antiferromagnetic (J = -1.77(5) cm(-1)) as well as weak ferromagnetic (J' = 0.08(2) cm(-1)) Mn-Mn exchange interactions. In 2 the Cu-Cu exchange interactions are antiferromagnetic (J = -0.10(2) cm(-1), J' = -0.29(2) cm(-1)).     

Synthesis and Crystal Structure of （4S）-5-（2-Methoxy-2-oxoethylamino）-5-oxo-4-（3,4,5-trimethoxybenzamido） Pentanoic Acid

1 INTRODUCTION Aminopeptidase N (APN), a member of mem- brane-bound zinc-dependent exopeptidase, is known to be high expression on the brush border membran- es of the small intestine and renal proximal tubules[1]. The over-expression of APN has been involved in several pathological conditions including cancer[2], leukemia, diabetic nephropathy[3], rheumatoid arth- ritis[4], angiogenesis[5] and central nervous system di- seases, such as Alzheimer’s disease[6]. This has led to the sear…