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1.
本文研究五氯·亚硝酰合铱酸根(1-)与二苯胺磺酸钠的显色反应。反应中〔Ir(NO)Cl_5〕-:二苯胺磺酸钠等于1:1.在4M盐酸溶液中吸收峰在525nm,摩尔吸光系数为2.6×10~4。实验证实生成了新的多元络合物。利用此反应,拟定了一个测定冶金中间产品中〔Ir(NO)Cl_5〕-态铱的方法,操作简便迅速,选择性极高。  相似文献   

2.
屈义彬  王镜明 《化学学报》1987,45(7):704-706
铱在萃取过程中的行为与其存在状态有关.王水溶解含铱物料有[Ir(NO)Cl_5]~-生成,亚硝酸盐配位法分离贵金属时,盐酸酸化可使[Ir(NO_2)_6]~(3-)转变为[Ir(NO)Cl_5]~-。[Jr(NO)Cl_5]~-在溶液中的变化极其复杂,它在冶金过程中必然影响到有关的分离.本文研究[Ir(NO)Cl_5]~-在盐酸-磷酸三丁酯(TBP)体系中的萃取行为,寻求最佳萃取条件.  相似文献   

3.
3-[二(羧甲基)氨甲基]-1, 2-二羟基蒽醌与蛋白质作用的研究   总被引:10,自引:0,他引:10  
在pH4.1的缓冲溶液中,研究3-[二(羧甲基)氨甲基]-1,2-二羟基蒽醌(AFB)与牛血清蛋白(BSA)结合反应,相互生成的紫色的配合物。采用UV光谱法,测得此配合物的最大吸收峰值为510nm,与试剂本身相比较红移90nm。表观摩尔吸光系数ε=1.2474×10^4mol^-^1.cm^-^1.L,最大结合数n=7,表观结合常数K~c=3.85×10^6。研究发现,AFB与BSA之间主要是以分子之间的静电引力结合,认为该反应符合Scatchard模型。离子强度对结合反应有显著的影响。  相似文献   

4.
铝-结天青S-锌-8-羟基喹啉混合多核配合物显色反应的研究   总被引:1,自引:0,他引:1  
详细地研究了铝-络天青S-锌-8羟基喹啉配合物的形成条件及有关反应过程。配合物的最大吸收峰位于548nm,摩尔吸光系数ε_(548)=6.4×10~4。配合物中各组分的摩尔比Al:CAS:Zn:HOx=2:6:3:3,相应的分子式为[Al(CAS)_3]_2[ZnHOx]_3。反应曾用于稀土样品中铝的测定,取得了比较满意的结果。  相似文献   

5.
自国甫  尹承烈 《化学学报》1998,56(5):484-488
用旋光活性2, 2'-(1, 1'-联萘)二胺和2-吡啶基甲醛缩合得到的Schiff碱BPMBNDI[N, N'-二(2-吡啶基亚甲基)-(1, 1'-联萘)-2, 2'-二亚胺]为配体与[Ir(COD)Cl]2(COD=1, 5-环辛二烯)反应, 生成了10个光学活性铱配合物。研究它们在异丙醇对苯乙酮不对称氢转移反应中的光学诱导活性时, 发现10个催化剂均具有较高的立体选择性,其中[Ir(COD)(BPMBNDI)I]催化的光学产率高达84%。  相似文献   

6.
本文通过紫外光谱法及萃取研究,讨论了二氯二正辛基亚砜合钯(Ⅱ)配合物[Pd(DOSO)_2Cl_2]在氯仿溶剂中的离解平衡: Pd(DOSO)_2Cl_2(?)Pd(DOSO)Cl_2 DOSO Pd(DOSO)Cl_2(?)PdCl_2 DOSO 并测定了25℃时的离解常数K_1=(2.0±0.3)×10~(-3),K_2=(1.3±0.1)×10~(-4)  相似文献   

7.
研究了咪唑桥联异三核配合物[(NH_3)_5CoImCu(dien)ImCo(NH_3)_5](ClO_4)_6·4H_2O与同构配合物[(NH_3)_5CoImZn(dien)ImCo(NH_3)_5]·4H_2O混合单晶在低温(100 K)下的ESR。应用适于求非同轴g张量和A张量的最小二乘法拟合技术,解出标题配合物的g张量和A张量主值分别为:g_1=2.246,g_2=2.093,g_3=2.048,A_1=1.63×10~(-2)cm~(-1),A_2=0.38×10~(-2)cm~(-1),A_3=0.17×10~(-2)cm~(-1)及g_1=2.245,g_2=2.090,g_3=2.051,A_1=1.64×10~(-2)cm~(-1),A_2=0.37×10~(-2)cm~(-1),A_3=0.17×10~(-2)cm~(-1)。配合物Cu~(2+)的4s、3d轨道上的电子自旋密度分别为0.018和0.557。Cu~(2+)与配体间的键有较强的共价性。  相似文献   

8.
本文在束-气条件下研究了Sr(~1S), Sr(~3P)+Cl_2的化学发光反应。实验压力为10~(-5)~10~(-4)Torr, 金属束炉温1000 K左右。同时, 观测和分析了Sr, Sr~*+Cl_2反应产物Sr(A,B)、SrCl_2~*的发光光谱。发现Cl_2压力(pcl_2)较低时, 主要生成SrCl~*; 而pcl_2增高时(>2×10~(-4)Torr), SrCl_2~*的发射光谱逐渐增强。实验结果表明, SrCl~*是单次碰撞的直接产物, 其发光强度(I_(SrCl)~*)与pcl_2、Sr的原子密度均为直线关系, 而I_(SrCl_2)~*与pCl_2成二次关系, 表明SrCl_2~*是SrCl~*和Cl_2碰撞的产物, 与BaCl_2~*的生成机理相同。由实验结果计算而得到的亚稳态Sr~*原子及基态Sr原子在Cl_2中的总消除截面分别为9.7±5 nm~2及5.8±5 nm~2。由此估计由亚稳态Sr~*及基态Sr与Cl_2反应生成SrCl(A)的相对光子产率为Φ~*/Φ~0=115。  相似文献   

9.
研究了新显色剂2-[2-苯骈噻唑偶氟]-5-二乙氨基苯甲酸[简称BTAEB]与铜的显色反应。试验结果表明,在pH 3.5~6.5范围内及丙酮存在下,Cu(Ⅱ)与BTAEB形成一稳定的蓝色配合物,其组成比为1:1,最大吸收波长为655nm,表观摩尔吸光系数为5.9×10~4,铜浓度在0~25μg/25ml范围内符合比耳定律。该方法灵敏度高、选择性好。应用于铝合金和工业污水中微量铜的测定,结果令人满意。  相似文献   

10.
合成了一类自主体蓝绿色磷光铱(Ⅲ)配合物(Cz Ph BI)2Ir(tfmptz),(Cz Ph BI)2Ir(tfmpptz)和(Cz Ph BI)2Ir(fpptz)[其中Cz Ph BI,tfmptz,tfmpptz和fpptz分别为9-[6-(2-苯基-1-苯并咪唑基)己基]-9-咔唑、2-(5-三氟甲基-1,2,4-三唑基)吡啶、2-(5-[4-(三氟甲基)苯基]-1,2,3-三唑)吡啶和2-[5-(4-氟苯基)-1,2,3-三唑]吡啶].通过核磁共振氢谱和氟谱及元素分析确定其分子结构,并对其光物理性能进行了研究.利用该类配合物作为单发光层制备了器件结构为氧化铟锡(ITO)│N,N'-二苯基-N,N'-二(1-萘基)-1,1'-联苯-4,4'-二胺(NPB)(30 nm)│4,4'-N,N'-二咔唑基联苯(CBP)(15 nm)│Ir配合物(30 nm)│1,3,5-三(1-苯基-1H-苯并咪唑-2-基)苯(TBPI)(30 nm)│Li F(1 nm)│Al(100 nm)的电致发光器件,其最大亮度为6913 cd/m2,最大发光效率达13.9 cd/A.  相似文献   

11.
Synthesis and Structure of Ammine and Amido Complexes of Iridium The reaction of (NH4)2[IrCl6] with NH4Cl at 300 °C in a sealed glass ampoule yields the iridium(III) ammine complex (NH4)2[Ir(NH3)Cl5], which crystallizes isotypically with K2[Ir(NH3)Cl5] in the orthorhombic space group Pnma with Z = 4, and a = 1350.0(2); b = 1028.5(3); c = 689.6(2) pm. The reaction of (NH4)2[IrCl6] with NH3 at 300 °C, however, gives the already known [Ir(NH3)5Cl]Cl2 beside a small amount of [Ir(NH3)4Cl2]Cl2. In pure form [Ir(NH3)5Cl]Cl2 is obtained by ammonolysis of (NH4)2[Ir(NH3)Cl5] at 300 °C with NH3. [Ir(NH3)4Cl2]Cl2 crystallizes triclinic (P1, Z = 1, a = 660,2(3); b = 680,4(3); c = 711,1(2) pm; α = 103,85(2)°, β = 114,54(3)°, γ = 112,75(2)°). The structure contains Cl anions and [Ir(NH3)4Cl2]2+ cations with a trans position of the Cl atoms. Upon reaction of [Ir(NH3)5Cl]Cl2 with Cl2 one ammine ligand is eliminated yielding [Ir(NH3)4Cl2]Cl, which is transformed to orthorhombic [Ir(NH3)4(OH2)Cl]Cl2 (Pnma, Z = 4, a = 1335,1(3); b = 1047,9(2); c = 673,4(2) pm) by crystallization from water. In the octahedral complex [Ir(NH3)4(OH2)Cl]2+ the four ammine ligands have an equatorial position, whereas the Cl atom and the aqua ligand are arranged axial. Oxidation of (NH4)2[Ir(NH3)Cl5] with Cl2 at 330 °C affords the tetragonal IrIV complex (NH4)[Ir(NH3)Cl5] (P4nc, Z = 2, a = 702.68(5); c = 912.89(9) pm). Its structure was determined using the powder diagram. Oxidation of (NH4)2[Ir(NH3)Cl5] with Br2 in water, on the other hand, gives (NH4)2[IrBr6] crystallizing in the K2[PtCl6] type. Oxidation of (PPh4)2[Ir(NH3)Cl5] with PhI(OAc)2 in CH2Cl2 affords the IrV amido complex (PPh4)[Ir(NH2)Cl5].  相似文献   

12.
High yielding syntheses of 1‐(ferrocenylmethyl)‐3‐mesitylimidazolium iodide ( 1 ) and 1‐(ferrocenylmethyl)‐3‐mesitylimidazol‐2‐ylidene ( 2 ) were developed. Complexation of 2 to [{Ir(cod)Cl}2] (cod=cis,cis‐1,5‐cyclooctadiene) or [Ru(PCy3)Cl2(?CH‐o‐O‐iPrC6H4)] (Cy=cyclohexyl) afforded 3 ([Ir( 2 )(cod)Cl]) and 5 ([Ru( 2 )Cl2(?CH‐o‐O‐iPrC6H4)]), respectively. Complex 4 ([Ir( 2 )(CO)2Cl]) was obtained by bubbling carbon monoxide through a solution of 3 in CH2Cl2. Spectroelectrochemical IR analysis of 4 revealed that the oxidation of the ferrocene moiety in 2 significantly reduced the electron‐donating ability of the N‐heterocyclic carbene ligand (ΔTEP=9 cm?1; TEP=Tolman electronic parameter). The oxidation of 5 with [Fe(η5‐C5H4COMe)Cp][BF4] as well as the subsequent reduction of the corresponding product [ 5 ][BF4] with decamethylferrocene (Fc*) each proceeded in greater than 95 % yield. Mössbauer, UV/Vis and EPR spectroscopy analysis confirmed that [ 5 ][BF4] contained a ferrocenium species, indicating that the iron center was selectively oxidized over the ruthenium center. Complexes 5 and [ 5 ][BF4] were found to catalyze the ring‐closing metathesis (RCM) of diethyl diallylmalonate with observed pseudo‐first‐order rate constants (kobs) of 3.1×10?4 and 1.2×10?5 s?1, respectively. By adding suitable oxidants or reductants over the course of a RCM reaction, complex 5 was switched between different states of catalytic activity. A second‐generation N‐heterocyclic carbene that featured a 1′,2′,3′,4′,5′‐ pentamethylferrocenyl moiety ( 10 ) was also prepared and metal complexes containing this ligand were found to undergo iron‐centered oxidations at lower potentials than analogous complexes supported by 2 (0.30–0.36 V vs. 0.56–0.62 V, respectively). Redox switching experiments using [Ru( 10 )Cl2(?CH‐o‐O‐iPrC6H4)] revealed that greater than 94 % of the initial catalytic activity was restored after an oxidation–reduction cycle.  相似文献   

13.
利用时间分辨激光光解技术研究了季铵盐型离子液体[Me3NC2H4OH]Zn2Cl5(简写R-Zn2Cl5)的光解行为, 研究发现离子液体能被266 nm激光单光子电离, 生成阳离子自由基、[Zn2Cl5]中性自由基和水合电子, 观察到胆碱激发三线态的存在, 并测定了离子液体光电离的量子产额为0.04. 利用266 nm激光对离子液体、胆碱、氯化锌、氯化钠的光解行为比较, 发现胆碱阳离子的贡献很小, [Zn2Cl5]阴离子起主要作用. 采用氧化性自由基SO4•-引发离子自由基, 揭示其光电离机理, 测定离子液体的动力学反应速率常数, SO4•- 460 nm的衰减速率常数为1.3×109 L•mol-1•s-1, 320 nm离子自由基瞬态产物的生成速率常数为1.5×109 L•mol-1•s-1, 两者很接近, 说明SO4•-自由基的衰减与瞬态自由基的生成是同步的.  相似文献   

14.
Abstract

The equilibrium coefficient, K1, for the reaction [PdCl4]2- + RR′ SO ? [Pd(RR′ SO)Cl]? + Cl?, has been determined for dimethylsulfoxide, tetramethylensulfoxide, and phenylmethylsulfoxide and found to be 67, 46 and 8.8 respectively at 25°C, ü= 1.0 in 95:5 methanol-water. Values for the equilibrium constants for the dimethylsulfoxide complex are also reported at other ionic strengths. The equilibrium constants for the second stage, [Pd(Me2SO)Cl3]- + Me2SO)?-[Pd(Me2SO)2Cl2] + Cl?, has been determined for dimethylsulfoxide only, K2=2.5 × 10?2 at 25°C (μ not controlled). The causes of the mutual destabilisation of two dimethylsulfoxides are discussed.  相似文献   

15.
The complexes [Pt(3′′‐clpbpy)Cl2] ( 1 ) [3′′‐clpbpy = 4‐(3′′‐chlorophenyl)‐6‐phenyl‐2, 2′‐bipyridine], [Pt(4′′‐clpbpy)Cl2] ( 2 ) [4′′‐clpbpy = 4‐(4′′‐chlorophenyl)‐6‐phenyl‐2, 2′‐bipyridine], [Pt(3′′‐brpbpy)Cl2] ( 3 ) [3′′‐brpbpy = 4‐(3′′‐bromophenyl)‐6‐phenyl‐2, 2′‐bipyridine], and [Pt(4′′‐brpbpy)Cl2] ( 4 ) [4′′‐brpbpy = 4‐(4′′‐bromophenyl)‐6‐phenyl‐2, 2′‐bipyridine] were synthesized and characterized. The binding of the complexes with herring sperm DNA (HS DNA) was investigated by absorption titration and viscosity measurements. It was found that the complexes have ability of interaction with DNA by covalent mode. The intrinsic binding constant Kb of the complexes with HS DNA is 8.76 × 104 ( 1 ), 9.89 ×104 ( 2 ), 1.52 × 105 ( 3 ), and 2.31 × 105 ( 4 ) M–1. The slight depression in relative specific viscosity was observed, which also attributes to covalent binding of complexes with DNA bases. Gel electrophoresis assay demonstrated the ability of the complexes to unwind negatively supercoiled pUC19 plasmid by 14° ( 1 ), 13° ( 2 ), 13° ( 3 ), and 11° ( 4 ). The in vitro cytotoxic property of the synthesized metal complexes was also carried out against brine shrimp bioassay.  相似文献   

16.
Cu(II) complexes of the tridentate ligand N-(methylpyridin-2-yl)-amidino-O-methylurea (L), namely [Cu(L)Cl2] and [Cu(L)ClO4]ClO4, have been investigated for interactions with DNA by spectroscopic methods and viscosity measurements. Both complexes bind to DNA through non-intercalative interactions. [Cu(L)Cl2] (K b = 2.81 × 105 M?1) shows similar DNA-binding potential to [Cu(L)ClO4]ClO4 (K b = 1.57 × 105 M?1). Investigation of the chemical nuclease properties toward plasmid pBR322 DNA by gel electrophoresis and atomic force microscopy (AFM) suggests that both complexes are able to cleave the supercoiled form (Form I) to the nicked (Form II) and linear forms (Form III) through an oxidative pathway. The possible reactive oxygen species have been investigated by the use of scavengers, indicating that hydroxyl radicals may be involved in the DNA cleavage mechanism. Both of these complexes show similar activities against selected human cancer cell lines.  相似文献   

17.
A procedure for the synthesis of mpa h c-[Ru(NO)(NH3)4(OH)]Cl2 in a nearly quantitative yield (~95%) comprising treatment of a solution of (NH4)2[Ru(NO)Cl5] with ammonium carbonate at t ~80°C was developed. It was found that [Ru(NO)(NH3)4(H2O)]Cl3·H2O and trans-[Ru(NO)(NH3)4Cl]Cl2 formed in the reaction of [Ru(NO)(NH3)4(OH)]Cl2 with hydrochloric acid at various temperatures most often contain some initial hydroxy complex. The former compound is unstable, even at room temperature, it slowly eliminates water and HCl. A procedure for preparing the latter compound in a pure state in 85–90% yield was proposed. The acidity constant of the complex trans-[Ru(NO)(NH3)4(H2O)]3+ at room temperature (K a = (4 ± 1) × 10?2) was estimated by 14N NMR spectroscopy.  相似文献   

18.
The reactions of Cp*M(PMe3)Cl2 (M = Rh ( 1a ), Ir ( 1b )) with (NEt4)2[WS4] led to the heterodimetallic sulfido‐bridged complexes Cp*M(PMe3)[(μ‐S)2WS2] (M = Rh ( 2a ), Ir ( 2b )), whereas the dimers [Cp*MCl(μ‐Cl)]2 (M = Rh ( 4a ), Ir ( 4b )) reacted with (NEt4)2[WS4) to give the known trinuclear compounds [Cp*M(Cl)]2(μ‐WS4) (M = Rh ( 5a ), Ir ( 5b )). Hydrolysis of the terminal W=S bonds converts 2a, b into Cp*M(PMe3)[(μ‐S)2WO2] (M = Rh ( 3a ), Ir ( 3b )). Salts of a heterodimetallic anion, A[CpMo(I)(NO)(WS4)] ( 6 ) (A+ = NEt4+, NPh4+) were obtained by reactions of [CpMo(NO)I2]2 with tetrathiotungstates, A2[WS4]. The complexes were characterized by IR and NMR (1H, 13C, 31P) spectroscopy, and the X‐ray crystallographic structure of Cp*Rh(PMe3)[(μ‐S)2WS2] ( 2a ) has been determined. The bond lengths and angles in the coordinations spheres of Rh and W in 2a (Rh···W 288.5(1) pm) are compared with related complexes containing terminal [WS42—] chelate ligands.  相似文献   

19.
The synthesis, characteristics and analytical reactions of 1-(1,2,4-triazoly 1-3-azo)-2-naphthol are described. Coloured complexes are formed with 21 metal ions. For the cadmiuin(II) complex, the molar absorptivity is 2.8 × 104 1 mol-1 cm-1 at 515 nm for 40% (vv) ethanolic solutions at pH 8.0. For the mercury(II) complex at pH 10, the molar absorptivity is 2.7 × 104 mol-1 cm-1 at 530 nm. Complexes of the ML2 type are formed.  相似文献   

20.
A sensitive flotation—spectrophotometric method, based on the ion-associate formed by the anionic chloride and chlorostannate(II) complex of iridium with the basic dye rhodamine 6G (R6G) is described. A sparingly soluble compound precipitates when the aqueous phase is shaken with di-isopropyl ether. The separated and washed compound is then dissolved in acetone. The molar absorptivity is 3.6 × 105 l mol-1 cm-1 at 530 nm. Beer's law is obeyed. The component ratios in the isolated compound were determined, and the formula [(R6G+)3IrCl2(SnCl3)3-4] · [(R6G+)(SnCl-3)] is proposed for the adduct. The effects of other noble metals were examined. The interferences of rhodium and platinum with the determination of iridium in the proposed method can be greatly decreased by a preliminary extractive separation of iridium into chloroform as a tetraphenylarsonium hexachloroiridate(IV) complex. Optimum conditions for the iridium extraction are reported.  相似文献   

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