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1.
本文以2-氰基-4-硝基-6-溴苯胺为原料,经重氮化后与邻异丙基苯酚偶联,合成2-(2-氰基-4-硝基-6-溴苯偶氮)-6-异丙基苯酚,用乙醇重结晶精制。用元素分析,波谱等鉴定其结构,并测定其离解常数,研究该试剂的一般性质,发现其与Cu^2+,Ni^2+,Co^2+等的显色反应在吐温80表面活性剂存在下有较高的灵敏度。  相似文献   

2.
Cu(phen)2+2和Cu(bpy)2+2与6-巯基嘌呤、腺嘌呤相互作用的研究   总被引:9,自引:0,他引:9  
在pH为7.0的磷酸盐缓冲溶液中,用荧光光谱、紫外光谱、电化学及紫外光谱电化学等方法研究了铜配合物与6-巯基嘌呤、腺嘌呤的相互作用.结果表明,Cu(phen)2+2和Cu(bpy)2+2与6-巯基嘌呤、腺嘌呤发生了相互作用,但作用程度不同.根据荧光光谱实验数据计算出Cu(phen)2+2和Cu(bpy)2+2与6-巯基嘌呤、腺嘌呤的配位比均为1∶1;它们与6-巯基嘌呤作用的配位常数分别为2.23×104L/mol和6.11×104L/mol;与腺嘌呤作用的配位常数分别为1.95×104L/mol和5.12×104L/mol.电化学实验也获得了相近的结果.这为解释Cu(phen)2+2和Cu(bpy)2+2与DNA的作用机理及作用部位提供了有益的信息  相似文献   

3.
研究了新显色剂1-(6-硝基-2-苯并噻唑)-3-(4-硝基苯)-三氮烯(NBTNPT)与锌的显色反应,在非离子表面活性剂TritonX-100存在下,pH10.1~10.8的Na2B4O7-NaOH缓冲溶液中,Zn2+与试剂能形成1∶2的橙黄色配合物,最大吸收波长为446nm,同时在528nm处配合物表现有最大负吸收,其表观摩尔吸光系数分别为ε=7.03×104L·mol-1·cm-1和ε=1.06×105L·mol-1·cm-1.用拟定的方法测定了人发和婴儿奶粉中的微量锌,结果令人满意.  相似文献   

4.
1 引 言 DBC-偶氮氯膦全称为:2-(4-氯-2-膦酸基苯偶氮)-7-(2,6-二溴-4-氯苯偶氮)-1,8-二羟基3,6-萘H磺酸,简写为DBC-CPA。它已用于稀土、钡、锶、钙和钐的测定。作者在研究了该试剂与铁显色反应的基础上,又研究了与铋的显色反应,发现在1.2moL/L HClO4的介质中,于少量乙醇存在下,试剂与铋生成2:1的络合物,络合物稳定性好,灵敏度高,其表观摩尔吸光系数 1.08× 105 L·mol-1·cm-1,常见离子:银、镁、镉、钴、镍、铜、锰、铝、锌、铁、铬、硅等允许共…  相似文献   

5.
痕量硝基酚的反相高效液相色谱电化学检测   总被引:10,自引:0,他引:10  
蒋淑敏  傅承光 《分析化学》1997,25(3):286-289
本文以甲醇与0.03mol/L邻苯二甲酸氢钾缓冲液为淋洗液,采用安培型电化学检测,实现了2-硝基苯酚,3-硝基苯酚,4-硝基苯酚及2,4-二硝基苯酚和2,6-0二硝基苯酚等五种酚类化合物于Perkin-Elmer Nucleosil C8柱上反相高效液相色谱的分离及在E=+1.2V时于玻碳电极上的同时检测。  相似文献   

6.
新试剂1-(6-硝基-2-苯并噻唑)-3-(4-硝基苯)-三氮烯与汞(Ⅱ)显色反应的研究及应用金传明龚楚儒胡宗球杨明华(湖北师范学院化学系黄石435002)关键词1-(6-硝基-2-苯并噻唑)-3-(4-硝基苯)-三氮烯显色反应汞中图分类号O657....  相似文献   

7.
合成了两种稀土高氯酸盐与L-脯氨酸配合物的晶体.经热重、差热、化学分析及对比有关文献,知其组成 是[Pr2(L-Pro)6(H2O)4](ClO4)6和[Er2(L-PrO)6(H2O)4](ClO4)6,质量分数为99.24%和98.20%.选用RE(NO3)· 6H2O(RE=Pr,Er)、LPro、NaClO4·H2O和 NaNO3作辅助物,使用具有恒温环境的反应热量计,以 2 mol·L-1HCl 作溶剂,分别测定了[2RE(NO3)3·6H2O+6L-PrO+6NaClO4·H2O]和{ [RE2(L-PrO)6(H2O)4](ClO4)6+6NaNO3}在 298.15 K时的溶解热.设计一热化学循环求得化学反应的反应焓rH分别是:63.904 kJ·mol-1和 91.017 kJ·mol-1,经计算得配合物[RE2(L-Pro)6(H2O)4](ClO4)6(s)在 298.15 K时的标准生成焓(298.15 K)分别 是-6 594.78 kJ·mol-1和-6 532.87 kJ·mol-1。  相似文献   

8.
本文应用薄层色谱紫外光度法,测定了产品中的主要成分2-氰基-4-硝基苯胺和杂质,得到了满意的分析结果。与经典化学法比较,这种方法具有简单、快速、精确的特点。回收率99%~101%,相对标准偏差0.7%~1.1%,2-氰基-4-硝基苯胺含量在0~135μg/25mL范围内遵守比耳定律。  相似文献   

9.
合成了硝酸铒与四功能团含磷萃取剂6,6'-二(二苯基氧化膦甲基)-1,1'-氮氧化-2,2'-联吡啶的配合物。用四圆衍射仪测定了配合物的晶体结构。晶体属单斜晶系,空间群C2/c,晶体学参数,a=1.9830(4)nm,b=2.3135(4)nm,c=1.8600(3)nm;β=96.18(2)°,z=4。配合物中有机配体以四齿形式与中心离子铒配位,金属离子的配位数为8。配位几何构形为稍变形的四方反棱柱。金属离子周围的配位水分子已全部被取代。  相似文献   

10.
本文报道了以2-(6-甲基-2-苯并噻唑偶氮)-5-二乙氨基酚(MBTAE)作柱前衍生化试剂,在SpherisorbC_8柱上,以甲醇:水=80:20(V/V),含2mmol/LLi_2SO_4和10mmol/LpH5.0醋酸盐缓冲溶液作流动相,反相高效液相色谱分离和测定了Fe ̄(2+)、Co ̄(2+)、Ni ̄(2+)和Cu ̄(2+)。各金属离子的检出限(S/N=3)分别为(pg):Fe ̄(2+)6.40,Co ̄(2-)1.38,Ni ̄(2+)4.47,Cu ̄(2+)7.28。方法用于欧洲标准局,黑麦草标样的分析,所得结果与标准值相符。  相似文献   

11.
Novel substituted derivatives of 3‐aryl‐5‐cyano‐6‐methylthiopyrimidine‐2, 4‐diones were synthesized by the reaction of ethyl 2‐cyano‐3,3′‐dimethylthioacrylate with arylureas in good yields. The structures of all title compounds were evaluated by elemental analyses and 1H NMR spectra and compound 2c was also confirmed by X‐ray diffraction. Hill reaction inhibitory activity of title compounds was assayed.  相似文献   

12.
It was found that 6-methyl-2-methylthio-4-cyanomethoxypyrimidine (O-isomer) reacted via the cyano group with ammonia and hydroxylamine to give an amldine and an amidoxime respectively. The O-isomer did not react with either primary or secondary amines under similar conditions, but nucleophilic substitution at position 2 of the O-isomer was effected by converting the 2-methylthio group into a 2-methylsu fonyl. 6-Methyl-2methylthio-3-cyanomethylpyrimidinone-4 (N3-isomer) formed imidazo[1, 2-a]pyrirnidinones-5 with ammonia and primary amines, 2-amino-6-methyl-3-cyanomethylpyrirrtidinones-4 with secondary amines and either an amidoxime or an imidazo[1, 2-a]pyrimidinone-5 with hydroxylamine, depending on the reaction temperature.Vilnius University. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 703-707, May, 1996. Original article submitted November 3, 1995.  相似文献   

13.
The photoinduced reaction of a mixture of (Z)‐α‐cyano‐β‐bromomethylcinnamide (1) and (E)‐α‐cyano‐β‐bromomethylcinnamide (2) with 1‐benzyl‐1, 4‐dihydronicotinamide produces a mixture of the (E)‐ and (Z)‐ isomers of α‐cyano‐β‐methylcinnamide (3 and 4). Using spin‐trapping technique for monitoring reactive intermediate, it is shown that the reaction proceeds via electron transfer‐debromination‐H abstraction mechanism. The thermal reaction of the same substrate with BNAH at 60°C in the dark gives three products: the (E)‐ and (Z)‐isomers of α‐cyano‐β‐methylcinnamide and a dehydrodimeric product; 2, 7‐dicyano‐3, 6‐diphenylocta‐2, 4, 6‐trien‐1, 8‐dioic amide (7). Based on product analysis, scavenger experiment and cyclic voltammetry, an electron transfer‐debromination‐disproportionation mechanism is proposed.  相似文献   

14.
A photochemical cycloaddition reaction of methyl 2-pyrone-5-carboxylate with methacrylonitrile mainly gave a [4 + 2] cycloadduct, assigned as methyl endo-8-cyano-exo-8-methyl-3-oxo-2-oxabicyclo[2.2.2]oct-5-ene-6-carboxylate, whose structure was determined by an X-ray diffraction study. The formation of the cycloadduct was reasonably explained by considering a biradical intermediate having a less steric hindrance between the methoxycarbonyl group and the cyano group.  相似文献   

15.
Diethyl 6-amino-2-hydroxyazulene-1,3-dicarboxylate ( 6a ) and 2-acetoxyl derivative ( 6b ) were synthesized by reduction of the 6-azido derivatives ( 5a,b ) with zinc/acetic acid in excellent yields. 5a and 5b were prepared by azidation of diethyl 2-acetoxy-6-bromoazulene-1,3-dicarboxylate (4). Diazotization of 6a with sodium nitrite in the presence of concentrated sulfuric acid in dioxane gave diethyl 2-hydroxy- ( 7a ), 2,6-dihydroxy- ( 8a ), and 2-hydroxy-6-[2-(2-hydroxyethoxy)ethoxy]-azulene-1,3-dicarboxylates ( 9a ), in 5, 35 and 20% yields, respectively. Similar reaction of 6b gave the corresponding acetates 7b, 8b , and 9b , compounds of the same type from 6a . No evidence for the formation of 6-diazo-1,3-diethoxycarbonyl-2(6H) azulenone ( 2b ) was obtained in the employed reaction conditions.  相似文献   

16.
Methods of synthesis of 5-carbomethoxy-substituted pyrazolo[3,4-b]pyridines and 3H-imidazo[4,5-b]pyridines by their reaction with hydrazine hydrate or as a result of Hofmann rearrangement of the corresponding 2-aminopyridines were developed based on 4-aryl-3-carbamoyl(or cyano)-5-carbomethoxy-6-methyl-2-chloropyridines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No.12, pp. 1646–1650, December 1992.  相似文献   

17.
3,6—二氯吡啶甲酸杂质分离及色谱峰纯度分析   总被引:1,自引:1,他引:0  
1前言3,6-M氯吡啶甲酸是由2一氰基毗陡经过多步反应而成,由于转化不完全及其相应的反应副产物的产生,反应中伴随产生3,5,6一三氯一个氰基毗咤甲酸。2一氰基毗陡、四氯一2一氰基毗院等,从而影响最终产物的纯度。将3,6一二氯毗陡甲酸与反应过程中这些伴随组份有效进行分离,这对提高3,6一二氯毗睛甲酸的纯度是非常关键的。同样,对最终产物3,6一二氯11比院甲酸的纯度如何进行有效的鉴别也是十分重要的。我们曾多次采用常规的液相色谱方法,试图将3,6一二氯毗定甲酸及其伴随组份进行分离,其结果都不理想,本研…  相似文献   

18.
孔祥文  张静 《合成化学》1996,4(3):285-287
研究了环丁砜溶剂在N-丁基-3-氰基-4-甲基-6-羟基吡啶-2-酮的合成和由5-硝基靛红-3-肟热解合成2-氰基-4-硝基苯胺中的应用  相似文献   

19.
The reaction of cyano(cyclohexylidene)thioacetamide with cyanothioacetamide or malononitrile andN-methylmorpholine yieldsN-methylmorpholinium 6-amino-3,5-dicyano-1,4-dihydropyridine-4-spirocyclohexane-2-thiolate. Its structure was established based on the results of alkylation and X-ray structural analysis.Deceased.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2535–2540, October, 1996.  相似文献   

20.
采用溶胶-凝胶法制备了二氧化硅负载硅钨钼酸催化剂。以二氧化硅负载硅钨钼酸为催化剂,环己酮和1,2-丙二醇为原料合成了环己酮1,2-丙二醇缩酮,用正交实验法研究了反应物料配比、催化剂用量、带水剂用量、反应时间等因素对反应的影响。结果表明,在n(环己酮)∶n(1,2-丙二醇)=1∶1.4,催化剂用量为反应物料总质量的0.8%,带水剂环己烷12 mL,反应时间45 min的优化条件下,环己酮1,2-丙二醇缩酮的收率可达84.93%。  相似文献   

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