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1.
4‐Halo‐2(5H)‐furanones were prepared by the halolactonization of 2,3‐allenoic acids. The subsequent Suzuki coupling reaction of 4‐halo 2(5H)‐furanones with aryl boronic acids was carried out to produce 4‐aryl‐2(5H)‐furanones in excellent yields.  相似文献   

2.
裴伟伟  王鹏 《有机化学》2000,20(6):889-892
提出了一条方便地制备5-芳基-3,5-二乙氧基-2(5H)-呋喃酮化合物的合成路线,并对合成路线的反应机理进行了研究。应用设计的路线,合成了一组新颖的高度官能团化的2(5H)-呋喃酮化合物,所有化合物的结构均经过元素分析或高分辨率质谱,IR,NMR和MS确证。  相似文献   

3.
新手性源5-(l-孟氧基)-3-溴-2(5H)-呋喃酮的合成和结构   总被引:7,自引:0,他引:7  
黄慧  陈庆华 《化学学报》1999,57(5):538-540
文中深入研究了5-(l-孟氧基)-3-溴-2(5H)-呋喃酮新手性源(5a)的合成方法及其不对称合成反应。5a不仅制备方法简便,光学纯度单一,而且它作为稳定的Michael受体,可与碳、氧、氮、硫等不同的亲核试剂发生串联的Michael加成/分子内亲核取代反应,制备得到含有多个手性中心的双环[3.3.0^3^,^7]-5-辛烯类化合物、双环[3.1.0^3^,^5]-己烷类化合物和螺-环丙烷类化合物。本文报道了该手性呋喃酮5a的合成和构型测定。  相似文献   

4.
本文研究2(3H)呋喃酮的热转化和碱催化成2(5H)呋喃酮的过程。应用NMR跟踪技术测定了转化动力常数, 计算了活化能, 这对确定适宜的转化条件具有实际指导意义。还对碱催化下的转化机理进行了探讨。  相似文献   

5.
施介华  徐秀珠 《分析化学》1998,26(12):1481-1484
采用在硅胶柱(ZORBAX SIL)上,以正己烷:乙酸=70:30:2.5为流动相及UV检测器(254nm)的高效液相色谱法分离和测定2-(4-羟基苯氧基)丙酸。在选定的色谱操作条例上,2-(4-羟基苯氧基)丙酸与杂质对苯二酚等之间具有良好的分离效果。该方法具有较好的重现性和准确性。  相似文献   

6.
The HeI photoelectron (PE) spectra of both 2(5H) furanone and its trans-chair-dimenc-compound (t-c-DFN) are reported.The assignment of the PES bands is made on the basis of band shapes,the PES results of the molecules which have the similar atomic groups,and the restricted Hartree-Fock (RHF) calculations for the molecules studied.From the results of both PES experimental and theoretical calculations,it is proved that the ionization potential (IPs) of the HOMO for the dimenc-compound is lower than that of the HOMO for the monomer.And the total energy computed for the t-c-DFN is the lowest in the four possible configurations of dimeric-compounds of 2(5H) furanone Therefore the synthesis of t-c-DFN is also the easiest.  相似文献   

7.
钯(Ⅱ)与二溴对甲基偶氮磺显色反应的研究   总被引:4,自引:0,他引:4  
钯(Ⅱ)与二溴对甲基偶氮磺在HNO3介质中形成组成比为1∶2的绿蓝色的配合物,其最大吸收波长位于610nm处,表观摩尔吸光系数ε610=4.0×104L·mol-1·cm-1,钯的质量浓度在0~0.80mg/L范围内符合比尔定律。该法常温下可在水相中直接测定微量钯。并应用于废钯催化剂回收液中钯的测定。  相似文献   

8.
3-(3-Aryl-4-formyl-1-pyrazolyl)propionic acids were synthesized by the reaction of 3-aryl-1-(2-cyanoethyl)-4-formylpyrazoles with concentrated hydrochloric acid. They were converted into the corresponding amides by the carbodiimide method.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1483–1486, October, 2004.For Communication 2, see [1].  相似文献   

9.
陈寒松  李正名 《中国化学》2000,18(4):596-602
In order to search for novel fungicides with high activity, a series of heteroaryl pyrazoles were synthesized from 5-pyra-zole formhydrazide. The structures of all new compounds were confirmed by spectroscopic methods and microanalyses. Preliminary bioassays indicated that some compounds showed fungicidal activity against Puccinia tritinia and PGR activity as well.  相似文献   

10.
Summary A number of substituted 2-(5-aryl-2-furyl)benzothiazoles and their vinylogues were synthesized from corresponding 5-arylfurfurals by convenient methods. The yields of products and their UV/Vis spectroscopic properties are substituent-dependent.
Synthese und absorptionspektroskopische Eigenschaften von substituierten Phenylfurylbenzthiazolen und ihren Vinylogen
Zusammenfassung Einige substituerte 2-(5-Aryl-2-furyl)benzthiazole und ihre Vinyloge wurden aus entsprechenden 5-Aryl-furfuralen synthetisiert. Die Ausbeuten an Produkten sowie ihre absorption-spektroskopischen Eigenschaften sind vom Substituenten abhängig.
  相似文献   

11.
In this paper, stereocontrolled tandem Michael addition-elimination reaction of the novel chiral source, 5-(l-menthyloxy)-3,4-dichloro-2(5H)-furanone, with various thiols and amines has been investigated. A series of new enantiomerically pure compounds, 5–(l-menthyloxy)-4-substituted-3-chloro-2(5H)-furanones, were obtained in good yields with d. e. ? 98% under mild conditions.  相似文献   

12.
在THF溶液中合成了标题化合物3-氯-4-二苄胺基-5-甲氧基-2(5H)-呋喃酮,并用FT-IR、UV-Vis、1HNMR、13C NMR、MS、元素分析和X-射线衍射等进行了表征。结果表明此化合物属正交晶系,空间群为Pbca,晶胞参数为:a=15.891(16),b=11.126(11),c=19.778(19),α=β=γ=90°,V=3497(6)3,Z=8,Dc=1.306Mg/m3,μ=0.234 mm-1,F(000)=1440。在化合物的分子结构中,两个苯环几乎垂直于呋喃酮平面,且它们与呋喃酮平面的两面角分别为89.38°和88.19°。  相似文献   

13.
Hexafluoroacetone and α-keto acids react to give 5,5-bis(trifluoromethyl) substituted 2(5H)-furanones and/or 2,2-bis(trifluoromethyl)-1,3-dioxolan-4-ones depending upon the substituent pattern of the side chain of the acid. A fluoroanalogue of the natural product zymonic acid was obtained from ethyl 3,3,3-trifluoropyruvate and 2-oxosuccinic acid in one step.  相似文献   

14.
高灵敏度分光光度法同时测定钴和铑的研究   总被引:1,自引:0,他引:1  
张光  刘彬 《分析试验室》1995,14(6):6-10
新显色剂5-(5-硝基-2-吡啶偶氮)-2,4-二氨基甲苯(5-NO2-PA-DAT),用作为测定钴和铑的高灵敏度试剂,在586nm处,钴及铑与试剂形成的配合物的吸光度具有很好的加和性。本文利用该试剂与钴,铑显色反应的温度差异,建立了一种高灵敏度光度法同时测定钴,铑的新方法。  相似文献   

15.
Abstract

Structure-activity relationships in inhibition of acetylcholinesterase by organophosphorus compounds (YO)(Z)P(O)SX have been analyzed using the equation log ki = C + ρσ + ?π with Taft σ* for substituent elehtronegativity and Hansch Π for hydrophobicity. The obtained relationships have been used for optimizing the structures of organophosphorus inhibitors for their maximum anticholinesterase activity.  相似文献   

16.
本文研究了新显色剂5-(对硝基苯偶氮)-8-(对甲苯磺酰氨基)喹啉(NPTSQ)与铂(Ⅱ)的显色反应。在强碱性介质中,NPTSQ与Pt(Ⅱ)形成1:2的紫蓝色络合物,λ_(max)=640nm,摩尔吸光系数为1.37×10~5L·mol~(-1)·cm~(-1)。铂量在0~25μg/25mL范围内遵守比尔定律。用于冶金氧化渣及铂催化剂中微量铂的测定,结果良好。  相似文献   

17.
研究了新合成试剂5-(5-氟-2-吡啶偶氮)-2,4-二氨基甲苯(5-F-PADAT)与钴(Ⅱ)的显色反应。实验表明,在pH4.7~9.0范围内,钴与试剂形成紫红色配合物,其最大吸收波长位于506 nm。该配合物在无机酸作用下,可转化为另一具有较高吸收特性的质子化型体,最大吸收波长红移到565 nm,适宜的酸浓度范围分别为:0.24~3.6 mol/L HClO4、0.16~3.84 mol/L H2SO4、0.48~2.4 mol/L HCl、0.64~3.84 mol/L H3PO4。配合物表观摩尔吸光系数ε565=9.1×104L.mol-1.cm-1,钴(Ⅱ)质量浓度在0~0.5μg/mL内符合比尔定律。所拟方法已应用于维生素B12针剂中微量钴的测定。  相似文献   

18.
以3-羟基苯甲腈为原料,经过6步反应(醚化、硝化、还原、甲脒的形成、环化和取代)合成了两个新型4-对丙烯基苯氨基喹唑啉衍生物4-[4-(E)-丙烯基苯氨基]-6-[2-吗啉基乙氧基]喹唑啉和4-[4-(E)-丙烯基苯氨基]-6-[3-吗啉基丙氧基]喹唑啉。化合物的结构经IR、HRMS、1H NMR和13C NMR确认。以人结肠癌细胞(SW480)、人肺癌细胞(A549)、人皮肤鳞状细胞癌细胞(A431)为模型,采用MTT法对所得化合物进行了体外抗肿瘤活性评价。结果表明,两个化合物均具有一定的抗肿瘤活性。特别是化合物4-[4-(E)-丙烯基苯氨基]-6-[3-吗啉基丙氧基]喹唑啉对所试肿瘤细胞均表现出良好的生长抑制活性(IC50:10.0~18.2μmol/L),与临床使用药物吉非替尼的活性(IC50:4.1~18.5μmol/L)相当。  相似文献   

19.
本文合成了对-(2-苯基-1,3,4,-噁二唑基-5)-(5’-苯基噁唑基-2’)苯和对-(2-苯基-1,3,4-噁二唑基-5)-(2’-苯基q罨唑基-5’)苯二类共12种化合物,测试了它们的紫外、荧光、红外光谱和激光转换效率.  相似文献   

20.
Dual-sensitive probe of 1-imidazole-2-(5-benzoacridine)-ethanone (IBAE) for the determination of free amines with fluorescence detection and online highly sensitive atmospheric chemical ionization-mass spectrometry identification (APCI-MS) has been developed. 2-(Benzoacridine)-5-acetic acid (BAAA) reacts with coupling agent N,N′-carbonyldiimidazole (CDI) to form a highly activated amide intermediate 1-imidazole-2-(5-benzoacridine)-ethanone (IBAE), which is dual-sensitive probe. The amide intermediate (IBAE) reacts preferably with amines in dimethylformamide (DMF) solvent to give the high yields of derivatives. IBAE-amine derivatives are not only sensitive to fluorescence but also to MS ionizable efficiency. The percent ionization δ values change from 0 to 57.32% in aqueous acetonitrile and from 0 to 62.14% in aqueous methanol. The relative standard deviations of the peak areas with fluorescence detection for each amine are <1.24% (40 ng/ml, n = 6). The fluorescence detection limits (at a signal-to-noise ratio of 3) are in the range of 0.15-0.50 ng/ml. The online APCI-MS detection limits are in the range of 2.07-8.51 ng/ml (at a signal-to-noise ratio of 3). Therefore, the facile IBAE intermediate derivatization allowed the development of a highly sensitive and specific method for the quantitative analysis of trace levels of amines in environmental water.  相似文献   

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