2-(3-羧基-2,4,5-三氮唑偶氮)-5-二甲氨基苯磺酸与镍的显色反应及应用

介绍新水溶性显色剂2-(3-羧基-2,4,5-三氮唑偶氮)-5-二甲氨基苯磺酸(CTZAMBS)与镍的显色反应研究及应用,建立了测定镍的新方法。在pH=7.26的NaH_2PO_4-Na_2HPO_4缓冲溶液中,该试剂与镍按1:1的比例形成稳定的紫红色络合物,λ_(max)为540.6nm,镍的浓度在0-1.0μg/L范围内符合比耳定律,表观摩尔吸光系数为2.86×10~4L/(mol·cm)。在氟化铵及硫脲的存在下,可直接测定镁和铝合金中的微量镍。     

5-[(3-磺羧基苯基)偶氮]-8-氨基喹啉的合成及其与铜的显色反应研究

以8-氨基喹啉为母体合成了5-[(3-磺羧基苯基)偶氮]-8-氨基喹啉(m-SPAQ)。在阳离子表面活性剂CT-MAB存在下,于pH8.3的缓冲溶液中,试剂与铜形成红色配合物,其最大吸收波长位于596mm,摩尔吸光系数为6.24×10~4L·mol~(-1)·cm~(-1),铜的量在0～20ug/25mL范围内符合比尔定律,此法用于铝合金中微量铜的测定,结果满意。     

1—（2—羟基—3,5—二硝基苯基）—3—[4—（苯基偶氮）苯基]—三氮烯与镉的显色反应

研究了新合成的1-(2-羟基-3,5-二硝基苯基)-3-[4-(苯基偶氮)苯基]-三氟烯(HDNPAPF)试剂,在乳化剂OP存在下与镉的显色反应。在pH为10.30～10.80的Na_2B_4O_7-NaOH介质中,镉与HDNPAPT形成1:1的红色配合物,表观摩尔吸光系数ε_(530)=1.85×10~5L/(mol·cm),镉浓度在0～0.6mg/L范围内符合比尔定律。该方法可用于电镀废水和环境水样中微量镉的测定。     

新试剂1-偶氮苯基-3-(5-硝基-2-吡啶)-三氮烯的合成及其与镉的显色反应

三氮烯试剂是测定ⅠＢ、ⅡＢ族金属元素的优良试剂。近年来 ,对该类试剂中的取代苯重氮氨基苯的合成和分析应用报道较多[1 ,2 ] ,但对含杂环的三氮烯试剂的研究报道较少。我们曾将安替比林[3] 、苯并噻唑[4,5] 、噻唑[6] 引入该类试剂中 ,使试剂灵敏度有所提高。为进一步探讨此类试剂的分析性能 ,我们将 5 硝基吡啶引入 ,合成了 1 偶氮苯基 3 ( 5 硝基 2 吡啶 ) 三氮烯 (ＡＢＮＰＤＴ)。分子中含有杂环吡啶的同时还有强吸电子———ＮＯ2存在 ,另一端为具有长共轭链的偶氮苯基 ,这样更有利于试剂分子中电子的流动 ,从而改善分析性能。…     

One-Pot Synthesis and Methylation of 3-[2-(1H-Benzimidazol-2-yl-Sulfanyl)-Acetyl]-Chromen-2-Ones

Abstract

3-(2-Bromoacetyl)coumarins (I), when treated with 2-mercatobenzimidazole (II) in acetone containing K₂CO₃ (mild base) and tetrabutylammonium bromide (TBAB) as a phase transfer catalyst, at room temperature yielded the title compound 3-[2-(1H-benzimidazole-2-yl-sufanyl)-acetyl]-chromen-2-one (III) in a one-pot synthesis. Alternatively, III could also be prepared by treating dithiocarbonic acid O-ethyl ester, S-[2-oxo-2-(2-oxo-2H-chromen3-yl)-ethyl] ester (V), with o-phenylenediamine (VI). The methylation of the title compound III was performed with dimethyl sulfate (DMS), in acetonitrile containing TBAB and K₂CO₃ at room temperature, resulting in 3-[2-(N-methyl-benzimidazol-2-yl-sulfanyl)]-acetyl-chromen-2-ones (VII). Alternatively, methylation of III could also be performed with DMS in acetonitrile containing K₂CO₃ as base and clay as surface catalyst. All the compounds were synthesized in good yields and their structures were confirmed by spectral and analytical data.

[Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental resource: ¹H NMR of IIIB, VB and VIIB]     

1-(2-羟基-3,5-二硝基苯基)-3-[4-(苯基偶氮)苯基]-三氮烯与锌的显色反应及其应用

研究了 1 (2 羟基 3,5 二硝基苯基 ) 3 [4 (苯基偶氮 )苯基 ] 三氮烯 (HDNPAPT)与锌(Ⅱ )的显色条件。在乳化剂OP存在下的氢氧化钠介质中 ,在 5 2 5nm波长处 ,锌与HDNPAPT形成稳定的 1∶2的红色配合物 ,表观摩尔吸光系数ε52 5=9.15× 10 4 L·mol- 1·cm- 1,锌 (Ⅱ )浓度在 0～ 10 μg/ 2 5ml范围内符合比耳定律。方法已应用于人发、面粉中微量锌的测定 ,结果满意     

DIASTEREOSELECTIVE SYNTHESIS AND STEREOCHEMISTRY OF (Z)-1-[3-ARYL-2-(PHENYLSULFANYL)-2-OXIRANYL]-1-ETHANONES

Diastereoselective synthesis of a series of (Z)-1-[3-aryl-2-(phenylsulfanyl)-2-oxiranyl]-1-ethanones was effected from the reaction of (Z)-4-aryl-3-(phenylsulfanyl)-3-buten-2-ones with alkaline hydrogen peroxide in tetrahydrofuran. The stereochemistry of the oxiranes has been deduced from two-dimensional NOESY spectrum.     

1-(2,6-二氯-4-硝基苯)-3-(4-硝基苯)-三氮烯与铜的显色反应研究及其应用

研究了新试剂1-(2,6-二氯-4-硝基苯)-3-(4-硝基苯)-三氮烯(DCNPNPT)与铜(Ⅱ)显色反应。在表面活性剂Tween-80存在下,pH 9.0～10.0范围内,铜(Ⅱ)与DCNPNPT形成1:4黄色配合物,其最大吸收波长为460nm,用双峰双波长法测定,表观摩尔吸光系数为1.I×10~5L·mol~(-1)·cm~(-1)。铜(Ⅱ)含量在0～240μg·L~(-1)范围内符合比耳定律。拟定方法用于铜矿和环境水标样中铜的测定,结果满意。     

NEW CARBON-PHOSPHORUS BOND CONTAINING COMPOUND IN THE REACTION OF 2-ACETYLTHIOPHENE WITH PHOSPHORUS PENTACHLORIDE

Abstract

The treatment of 2-acetylthiophene with phosphorus pentachloride led, besides other products reported in previous studies, to 2-(2-thienyl)-2-chloroethenephosphonic acid in 16% yield. This compound was transformed, in the course of purification attempts, into 2-(2-thienyl)-2-oxoethanephosphonic acid. Full spectroscopic data for both compounds are provided.     

离子对高效液相色谱测定镉铅锌的5-硝基-2-[3-(4-磺苯偶氮苯)-1-三氮烯]苯胂酸配合物

以5-硝基-2-[3-(4-磺苯偶氮苯)-1-三氮烯]苯酸钠盐为柱前衍生试剂,在含3×10~(-3)mol·L~(-1)四丁基溴化铵和50mmOL·L~(-1)(pH 8.5)硼酸-氢氧化钠缓冲溶液的甲醇-水(68 32)流动相中,于505nm处,在C_(18)柱上于12min内实现了镉、铅、锌的同时分离测定,检出限(S/N=3)分别为0.6,0.2和1.2ng·ml~(-1)。方法灵敏度高,用于水样分析所得结果与推荐值相符,加标回收率为98.0％～102.7％。     

新试剂1-(2,3,5-三氮唑偶氮)-2-萘酚与锌的显色反应研究及应用

研究了１－（２,３,５－三氮唑偶氮）－２－萘酚（ＴＺＡＮ）锌显色反应,结果表明,在ＰＨ６．０－８．５的乙醇水溶液中ＴＺＡＮ与锌形成稳定的红色络合物,其最大吸收波长为５２５ｎｍ,表观摩尔吸光系数为３．５６＊１０＾４Ｌ．同,络合物的组成为Ｚｎ：ＴＺＡＮ＝ｌ：２,锌浓度在０－１．２μｇ．ｍｌ＾－１范围内遵守比耳定律,方法用于人发中微量锌的直接测定,结果满意。     

Synthesis and Properties of Derivatives of the new Heterocyclic System Benz[4,5]imidazo[1,2-c]pyrido[3',2';4,5]thieno[2,3-e]pyrimidine

Derivatives of a new heterocyclic system - benz[4,5]imidazo[1,2-c]pyrido[3',2';4,5]thieno[2,3-e]pyrimidine have been obtained by successive reactions in three stages - alkylation of 3-cyanopyridine-2(1H)-thiones with 2-chloromethylbenzylimidazole to give 2-benzimidazolylmethylthio-3-cyanopyridines, closing the thiophene ring in the latter to form 3-amino-2-(benzimidazolyl-2)thieno[2,3-b]pyridines, and cyclization of the pyrimidine ring by acylation with carboxylic acid anhydrides or chlorides.     

Synthesis and Crystal Structure of 1-（4-Fluorophenyl）-2-hexylthiobenzo[4,5]-furo[3,2-d]-1,2,4-triazolo[1,5-a]pyrimidin-5（1H）-one

The crystal structure of the title compound 1-(4-fluorophenyl) -2-hexylthio-benzo [4,5]furo[3,2-d]-1,2,4-triazolo[1,5-a]pyrimidin-5(1H) -one(C23H21FN4O2S,Mr = 436.5) has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic,space group P21/n with a = 13.9854(3) ,b = 17.2678(4) ,c = 18.1828(5) ,β = 99.364(2) °,V = 4332.58(18) 3,Z = 4,Dc = 1.338,F(000) =1824,μ = 0.185 mm-1,MoKa radiation(λ = 0.71073) ,R = 0.0538 and wR = 0.1162 for 4728 observed reflections with I > 2σ(I) . X-ray diffraction analysis reveals the fused rings of benzo[4,5]furo[3,2-d]-1,2,4-triazolo[1,5-a] pyrimidin-5(1H) -one system are nearly coplanar. The crystal packing is mainly stabilized by weak intermolecular C-H···O hydrogen bond and π-π interactions.     

Synthesis of （S）-2-（3-Arylacrylamido）-3-{4-[2-（5-methyl-2-phenyloxazol-4-yl）ethoxy]phenyl}propanoic Acids

The synthesis of （S）-2-（3-arylacrylamido）-3-{4-[2-（5-methyl-2-phenyloxazol-4-yl）etho- xy]phenyl}propanoic acids is described. Their structures were confirmed by ^1H-NMR.     

Synthesis of 6-amino-4-aryl-5-cyano-3-(3-cyanopyridin-2-ylthiomethyl)-2,4-dihydropyrano[2,3-c]pyrazoles and their hydrogenated analogs. Molecular structure of 6-amino-5-cyano-3-(3-cyano-4,6-dimethylpyridin-2-ylthiomethyl)-4-(2-nitrophenyl)-2,4-dihydropyrano[2,3-c]pyrazole

Substituted 3-hydroxypyrazoles, which were prepared based on ethyl esters of substituted 4-(pyridin-2-ylthio)- or 4-(1,4-dihydropyridin-2-ylthio)acetoacetic acids and hydrazine hydrate, were used in the synthesis of 6-amino-4-aryl-5-cyano-3-(pyridin-2-ylthiomethyl)-2,4-dihydropyrano[2,3-c]pyrazoles. The molecular and crystal structure of 6-amino-5-cyano-3-(3-cyano-4,6-dimethylpyridin-2-ylthiomethyl)-4-(2-nitrophenyl)-2,4-dihydropyrano[2,3-c]pyrazole was established by X-ray diffraction analysis.     

Reactions of 5-[3-(trifluoromethyl)-phenyl]furan-2-carbaldehyde

The Knoevenagel condensations of 5-[3-(trifluoromethyl)phenyl]furan-2-carbaldehyde with seven compounds containing an active methyl or methylene group have been studied. The compounds used were: methyl 2-cyanoacetate, malononitrile, 2-furylacetonitrile, acetophenone, 2-thioxo-1,3-thiazolidin-4-one (rhodanine), 5,5-dimethylcyclohexane-1,3-dione (dimedone), and methyl 2-azidoacetate. The effect of microwave irradiation on the condensation reactions was studied and compared with “’classical”’ conditions. Thermolysis of methyl 2-azido-3-{5-[3-(trifluoromethyl)phenyl]-2-furyl}propenoate afforded methyl 2-[3-(trifluoromethyl)phenyl)]-4H-furo[3,2-b]pyrrole-5-carboxylate. (2E)-3-{ 5-[3-(Trifluoromethyl)phenyl]-2-furyl}propenoic acid was converted to the corresponding azide, which was cyclized on heating into 2-[3-(trifluoromethyl)phenyl)]-4,5-dihydrofuro[3,2-c]pyridin-4-one. The latter after successive action of POCl₃ and NH₂NH₂-Pd/C gave 2-[3-(trifluoromethyl)-phenyl]furo[3,2-c]pyridine. Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 825–831, June, 2006.     

新显色剂5-磺酸基[杯(4)芳烃偶氮]氨基喹啉的合成及与钯显色反应的研究

合成了新试剂 5 磺酸基 [杯 (4)芳烃偶氮 ]氨基喹啉 (SCAQ) ,研究了该试剂与钯 (Ⅱ )显色反应的适宜条件 ,在pH 8.0的缓冲介质中 ,在非离子表面活性剂TritonX 10 0存在下 ,试剂与钯(Ⅱ )生成 1∶1稳定配合物 ,建立了测定钯 (Ⅱ )的光度法新体系 ,体系至少可稳定 6h ,λmax=6 6 0nm ,ε =7.88× 10 4 L·mol- 1·cm- 1,钯 (Ⅱ )浓度在 0～ 30 μg/ 2 5ml范围内服从比耳定律。方法已用于钯催化剂中钯 (Ⅱ )的测定 ,结果与原子吸收光谱法相符 ,RSD为 1.5 %～ 2 .6 %。     

Unusual scission of 3,7-dichlorobisisothiazolo[4,5-b:4",5"-e]pyrazine by nucleophiles

The reaction of 3,7-dichlorobisisothiazolo[4,5-b:4",5"-e]pyrazine with MeONa in MeOH afforded 3-chloro-5,6-dimethoxyisothiazolo[4,5-b]pyrazine. The reactions of the former with benzylamine, morpholine, and aniline gave rise to the corresponding N,N"-bis(5-amino-3-chloroisothiazol-4-yl)diazenes. In the case of benzylamine, 3,7-bis(benzylamino)bisisothiazolo[4,5-b:4",5"-e]pyrazine was isolated as a by-product. The crystal structure of N,N"-bis(5-benzylamino-3-chloroisothiazol-4-yl)diazene was established by X-ray diffraction analysis.     

二溴对甲基偶氮溴羧与钡显色反应的研究与应用

研究了新显色剂二溴对甲基偶氮溴羧与钡显色反应的条件。在磷酸介质中,试剂与钡形成2:1的络合物,最大吸收波长为610nm,摩尔吸光系数为2.13×10~4L·mol~(-1)·cm~(-1),钡量在0～20μg/25ml范围内符合比耳定律。两倍的锶和五倍的钛不干扰,钙的允许量较大,方法用于直接测定钛酸钡烧结物中微量钡,结果满意。