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1.
以2,2′-二氨基二苯醚和4-吡啶异氰酸酯反应合成了含吡啶二脲配体(L),并分别与HgCl_2和Cd(ClO_4)2进行了配位反应,得到2个配位聚合物{[Hg(L)Cl_2]·2DMF}_n(1)和{[Cd(L)_2(H_2O)_2](ClO_4)_2·4DMF·2H_2O·2CH_3OH}_n(2),采用1H NMR、MS、FTIR和元素分析等对化合物L进行了表征。通过X射线单晶衍射技术测定了配体及2个配合物的单晶结构,结构解析表明,2个配合物均为一维链状结构。进一步考察了2个配合物的热稳定性及其对甲醇蒸气的吸附性能。  相似文献   

2.
用差示脉冲极谱法研究了以琥珀酸(Succ)作为第一配体,草酸(OX)为第二配体与镉(Ⅱ)形成的混配三元配合物,计算表明,有3个三元配合物形成。在20±0.2℃时测得的稳定常数分别为:[Cd(OX)(Succ)]~(2-),Igβ_(11)=4.68;[Cd(OX)_2(Succ)]~(4-)、Igβ_(21)=5.75;[Cd(OX)(Succ)]~(4-),Igβ_(12)=5.68;在35±0.2℃结果为Igβ′_(11)=4.61,Igβ′_(21)=5.74,Igβ′_(12)=5.67,也求得配合物的热力学函数、混合常数K_((?))和稳定化常数K_((?))的对数值均大于零,说明三元配合物[Cd(OX)(Succ)]比对应的二元配合物稳定。  相似文献   

3.
以季铵盐配体L与Cd(NO_3)_2·4H_2O反应得到配合物[Cd(L)(NO_3)(H_2O)]·NO_3,并通过X射线衍射、红外光谱、质谱等表征了结构.单晶衍射结果表明中心原子Cd(Ⅱ)与去质子化的L~-的3个O原子和一个N原子,1个单齿配位的硝酸根,1个水的O原子和相邻配体2-吡啶N原子配位,形成一维链状结构.晶体属单斜晶系,Pn空间群,晶胞参数a=0.763 54(6)nm,b=0.912 15(7)nm,c=1.856 50(14)nm,α=90.00,β=91.524 0(10),γ=90.00,V=1.292 53(17)nm~3,Z=2,D_c=1.780 g/cm~3,μ=0.921 mm~(-1),F(000)=696,GOF on F~2=1.023,~aR_1[I2σ(I)],wR_2=0.037 7,0.090 6,R_1[all data],wR_2=0.043 7,0.094 4.  相似文献   

4.
王磊  孙培培 《分析化学》1992,20(6):648-651
本文首次合成了二溴邻羧基苯基重氮氨基偶氮苯(DB-o-CDAA)和二溴对羧基苯基重氮氨基偶氮苯(DB-p-CDAA)。在pH10.2的硼砂-氢氧化钠缓冲介质中,以TritonX-100为增溶增敏剂,两种试剂均可与Cd(Ⅰ)生成稳定的橙红色络合物。其DB-o-CDAA-Cd,λ_(max)=520nm,ε_(520)=2.21×10~5L·mol~(-1)·cm~(-1);DB-p-CDAA-Cd,λ_(max)=508nm,ε_(508)=1.12×10~5L·mol~(-1)·cm~(-1)。镉量在0~10μg/25ml范围内遵守比耳定律。用这两种试剂测定了环标水样及工业废水中的痕量镉,结果满意。  相似文献   

5.
采用水热方法,以2-吲哚甲酸(2-HINDF)为主配体,2,2’-联吡啶(2,2’-bpy)、1,10-邻菲罗啉(phen)为辅配体分别与碳酸铁和碳酸镉反应,合成了2个配合物[Fe(phen)_3](2-INDF)_2·8H_2O(1)和[Cd_4(2,2’-bpy)_8(2-INDF)_8]·7H_2O(2),利用元素分析、红外光谱、X-射线单晶衍射以及热重分析对其结构进行了表征。X-射线单晶衍射分析表明,配合物1晶体为单斜晶系,属于P2_1/c空间群,晶胞参数为a=12.995(3)?,b=31.842(6)?,c=13.073(3)?,β=110.23(3)?,V=5075.6(18)?~3,Mr=1060.89,Dc=1.388 g/cm~3,F(000)=2216,μ=3.70 mm~(-1),Z=4,最终偏离因子[Iσ(I)]R_1=0.0601,wR_1=0.1649。配合物2晶体为三斜晶系,属于P-1空间群,晶胞参数为a=13.276(3)?,b=13.591(3)?,c=21.764(4)?,α=78.77(3)?,β=80.87(3)?,γ=67.99(3)°,V=3555.2(13)?~3,Mr=3106.41,Dc=1.451 g/cm~3,F(000)=1582,μ=6.68 mm~(-1),Z=1,最终偏离因子[I2σ(I)]R_1=0.0629,wR_1=0.1753。  相似文献   

6.
钠快离子导体Na1+xZr2-yTiySixP3-xO12系统研究(Ⅰ)   总被引:2,自引:1,他引:2  
以Na_3PO_4、ZrP_2O_7、SiO_2、ZrO_2、TiO_2为反应原料,在1173K—1473K的高温下进行固相反应,制备了钠快离子导体Na_(1 x)Zr_(2-y)Ti_ySi_xP_(3-x)O_(12)系统中x=1、y=0—2.0的一系列合成物。研究了它们的相变关系;测定了两个单纯相—211相和202相的电导率和电导激活能。 室温时,211相的电导率σ_(RT)=1.52×10~(-4)(Ω·cm)~(-1),202相的σ_(TR)=0.53×10~(-4)(Ω·cm)~(-1);623K时,211相的电导率σ_(623)=1.21×10~(-1)(Ω·cm)~(-1),202相的σ_(623)=0.88×10~(-2)(Ω·cm)~(-1)。 在523K~673K温区里,211相的电导激活能E_a为31.87kJ/mole,202相的E_a为33.16kJ/mole。  相似文献   

7.
黄秋颖  林肖漪  王勇  朱永朝 《应用化学》2017,34(9):1093-1098
以四水合硝酸镉(Cd(NO_3)_2·4H_2O)与2-(邻溴)苯基-4,5-咪唑二羧酸(o-BrPhH_3IDC)和草酸铵通过水热反应,合成了一个波浪形一维链状配合物{[Cd(o-BrPhH_2IDC)_2(H_2O)]·H_2O}_n(1)。并通过元素分析、傅里叶变换红外光谱、热重分析和单晶X射线衍射等技术手段对配合物1进行了表征。结果表明,配合物1为正交晶系,Pbca空间群。配合物1在316 nm波长激发下,在356 nm处有最大的荧光发射峰。配合物1对小分子具有识别性能,乙腈使配合物荧光强度明显增强,甲醇、乙醇使配合物荧光强度明显减弱,而吡啶处理后的样品在356 nm附近的发射峰消失,显示对吡啶有识别作用。  相似文献   

8.
1,4-对苯二甲酸根桥联的镉(Ⅱ)配位聚合物研究   总被引:2,自引:2,他引:0  
使用2-溴-1,4-对苯二甲酸和2-氨基-1,4-对苯二甲酸为配体,在溶剂热条件下得到了两个结构新颖的化合物Cd(BrBDC)(py)(1)和Cd(NH2BDC)(H2O)(2)。单晶结构测试表明:化合物1中,Cd(Ⅱ)离子之间通过羧基连接成一维链,链与链之间通过配体连接成二维平面。化合物2中,Cd髤离子之间通过羧基连接成砖块结构的二维层,层与层之间通过氨基连接成三维结构。对化合物的荧光性质进行了表征。  相似文献   

9.
将2-甲氧基-5-氯-1,3-亚苯基二甲醛和邻氨基苯酚缩合制得了两种不同熔点和晶型的双Schiff碱C_(21)H_(17)ClN_2O_3(A和B),它们具有相同的UV、IR、NMR及MS。对其中结晶良好的块状单晶B进行了X射线衍射法结构分析。对于2610个1>2σ(I)的独立衍射点,最后偏离因子为R_1(F)=0.044,R_2F=0.057。空间群为P2_1/c。单胞参数:a=10.499(?),b=14.965(?),c=12.178(?),β=108.44°,V=1815(?)~3,Z=4,D_(计算)=1.39g/cm~3。分子呈伸展式结构。  相似文献   

10.
合成了2个2-氨基-3-羟基-吡啶Schiff碱双核Ni(Ⅱ)和Zn(Ⅱ)配合物,[Ni(L~1)(DMF)]_2(1)(H_2L~1=4-羟基-3-((3-羟基-吡啶-2-亚氨基))-苯并吡喃-2-酮)和[Zn(L~2)(H_2O)]_2·2DMF(2)(H_2L~2=2-((3,5-二溴-2-羟基)-氨基)-吡啶-3-醇),并通过元素分析、红外光谱、紫外-可见吸收光谱、荧光光谱及X射线单晶衍射分析等手段进行了表征。X射线单晶衍射分析结果表明:配合物1和2均具有双核结构,均由2个金属离子和2个配体单元以及2个配位的溶剂分子组成,不同的是配合物2含有2个溶剂分子。配合物1和2都是单斜晶系、P2_1/c空间群,且中心金属Ni(Ⅱ)和Zn(Ⅱ)离子的空间构型均为五配位的扭曲的四方锥。此外,配合物1和2通过分子间氢键、C-H…π及π…π作用形成3D超分子结构。此外,讨论了H_2L~1,H_2L~2及其相应的Ni(Ⅱ)和Zn(Ⅱ)配合物的荧光性质。配体H_2L~1和H_2L~2呈现蓝色发射,最大发射波长λ_(em)分别为457和473 nm,而配合物1和2显示绿色发射,λ_(em)分别为543和538 nm。  相似文献   

11.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

12.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

13.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

14.
Zhanhui Yang  Shiyi Yang  Jiaxi Xu 《Tetrahedron》2017,73(23):3240-3248
Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.  相似文献   

15.
16.
《Tetrahedron》2014,70(21):3377-3384
The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.  相似文献   

17.
Scope of the copper catalyzed/mediated selenium-nitrogen coupling reaction has been studied for the synthesis of isoselenazolones. It is noticed that the 2-chloro, 2-bromo-, and 2-iodo-aryl amides substrates can be exploited in the selenium-nitrogen coupling reaction by employing 25-100 mol % of CuI/1,10-phenanthroline (L) and potassium carbonate as a base in DMF. Furthermore, electron rich 2-chloro-arylamides also underwent selenium-nitrogen coupling reaction to give biologically important selenium-nitrogen heterocycles. Also, copper-catalyzed selenium-nitrogen coupling reaction has been meticulously applied for the synthesis of diaryl diselenides having methoxy, amine, and amide functionality from respective aryl iodides in the presence of stoichiometric amount of succinimide as an external Se-N coupling partner.  相似文献   

18.
A series of novel N-methyl morpholine (Nmm) based ionic liquids with 1,2-propanediol group were synthesized and used as catalysts for Knoevenagel condensation at room temperature in water. Under the effect of the catalyst, various aldehydes or aliphatic ketones could react with a wide range of activated methylene compounds well, including malononitrile, alkyl cyanoacetate, cyanoacetamide, β-diketone, barbituric acid, 2-arylacetonitrile and thiazolidinedione. Furthermore, most of the products could be separated just by filtrating and washing with water. Additionally, the catalyst is recyclable and applicable for the large-scale synthesis.  相似文献   

19.
A series of polyheterocyclic spirotetrahydrothiophene derivatives were obtained in moderate to excellent yields via a catalyst-free sulfa-Michael/aldol cascade reaction of chalcones 1 and commercially available 1,4-dithiane-2,5-diol 2 under mild conditions. We also present the first asymmetric sulfa-Michael/aldol cascade reaction of chalcones 1 and commercially available 1,4-dithiane-2,5-diol 2 with moderate to good enantioselectivities catalyzed by readily available chiral phase-transfer catalysts (PTCs).  相似文献   

20.
Both soluble guanylate cyclase (sGC) inhibitors ODQ 1 and NS2028 2 are synthesized via improved protocols. In the former case treating 3,4-dihydroquinoxalin-2(1H)-one oxime 8, which can be prepared in two steps from 1,2-benzenediamine, with 1,1′-carbonyldiimidazole (CDI) gives the dihydro-ODQ 10 that in the presence of KMnO4 oxidises to give ODQ 1 in an overall yield of 46% starting from 1,2-benzenediamine. In the latter case, the synthesis affords NS2028 2 from 2-amino-4-bromophenol 3 in three steps with an overall yield of 85% and avoids the need for chromatography. Furthermore, Suzuki-Miyaura reaction conditions are described that enable the preparation of 8-aryl and 8-heteroaryl derivatives of NS2028 directly from NS2028 2. Finally, demethylation of the 8-(methoxyphenyl) substituted analogues afforded the 8-(hydroxyphenyl) derivatives 40-42. All new products are fully characterised.  相似文献   

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