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1.
以乙酰丙酮(1)的电氧化偶联产物3,4-二乙酰基-2,5-己二酮(2)为原料,在酸性介质中与取代苯胺(3a ̄3g)作用,得到1,4-二羰基的缩合产物2,5-二甲基-3,4-二乙酰基-1-芳基吡咯(4a ̄4g)。在相似的条件下,2与水合肼作用,则得到1,3-二羰基的缩合产物3,3',5,5'-四甲基-1,1'-二氢-4,4'-联吡唑(5)。  相似文献   

2.
潘富友  张孙玮 《分析化学》1998,26(4):443-446
首次合成了新显色剂2-(5-羧基-1,3,4-三氮唑偶氮)-5-二乙氨基酚,研究了它的性质及其与铋是色反应的条件。结果表明:试剂的分子式C18H16N6O3,分子量304.32,m.p.252℃,各级酸离解常数为pKa1=3.1,pKa2=7.5,pKa3=9.6;在pH7的NH4Ac介质中,试剂与铋形成紫红色络合物,λmax为540nm,对比度Δγ为120nm,络合物的NH4A介质中,试剂与铋形  相似文献   

3.
2-烷基-1,4-二甲氧基苯1a-d(烷基为CH3,CH3CH2,PhCH2,(CH3)3C)分别在HNO3-HOAc和NH4NO3-HOAc中反应后生成占绝对优势的硝化产物2-烷基-5-硝基-1,4-二甲氧基苯4a-d,而2-烷基-5-叔丁基-1,4-二甲氧基苯2a-d及2,5-二叔丁基-1,4-二苄氧基苯3在上述二种硝化体系中的反应在很大程度上取决于所用的硝化体系的性质及反应物的结构。对上述反  相似文献   

4.
邵瑞链  职承信 《化学学报》1993,51(12):1202-1208
本文研究了不同反应条件下3-羟基-5-甲基异恶唑(1)与3-甲基-2-对氯苯基丁酰氯(2a)的反应,提出了区域选择性合成O-和N-酰化产物的方法。在三乙胺存在下,乙腈为溶剂,1和2a~2e反应得到含量为88~96%的O-酰化产物3a~3e;而若将1转化为相应的异恶唑硅醚4,再与2a~2i反应,则得到含量为86~97%的N-酰化产物5a~5i。试验表明,在DMAP催化下,3a和5a可发生O-/N-酰  相似文献   

5.
报导了硫冠醚13,15-苯并-1,4,8,11-四硫杂环十六烷(TTmX)及其钯(Ⅱ)络合物(TTmX·2PdC_l2)的合成,并通过X射线衍射分析测定了该配体及其络合物的晶体结构。TTmX属单斜晶系,P_2_1/n空间群,晶胞参数:a=9.545(3),b=9.065(1),c=19.645(3)A,β=95.38(1)°,V=1692.3(5)A ̄3,Z=4,μ=5.26cm ̄(-1),Dc=1.30g·cm ̄(-3)。TTmX·2PdCl_2属正文晶系,Pbca空间群,晶胞参数:a=11.392(2),b=14.580(4),c=27.146(9)A,β=90.00(0)°,V=4509(2)A ̄3,Z=8,μ=24.12cm ̄(-1),Dc=2.02g·cm ̄(-3)。  相似文献   

6.
3-甲基-2-丁烯酸乙酯4经SeO2反式氧化、还原、溴化得到关键中间体4-溴-3-甲基-(2E)-丁烯酸乙酯7.7与三苯基胂反应生成季8.二氢香茅醛与8在K_2CO_3-乙醇-微量水的存在下反应,得到(2E,4E)-3,7,11-三甲基-2,4-十二碳二烯酸乙酯1a及其(2Z,4E)-异构体1b,产率74%。该反应具有(4E)-立体选择性,同时C-2双键发生部分构型转化。  相似文献   

7.
合成并表征了14种β-烷氧羰乙基三氯化锡与2-羟基-1-萘醛缩苯胺类席夫碱配合物。测定了其中β-丁氧羰乙基三氯化锡与2-羟基-1-萘醛缩对甲苯胺席夫碱配合物的晶体结构。晶体属于三斜晶系,P1-空间群。晶胞参数:a=1.2487(6)nm,b=1.3551(7)nm,c=0.9385(3)nm,α=92.85(3)°,β=104.68(3)°,γ=70.43(4)°,V=1.4464(1)nm3,Dc=1.33g/cm3,Z=2,F(000)=588。配合物为畸变的八面体构型,配体以酚羟基氧原子与锡原子配位,分子内存在着羰基氧原子与锡原子的配键  相似文献   

8.
研究了1-芳基-4-乙氧羰基-5-氨基-1,2,3-连三唑(1)同甲酰胺、异氰酸磺酰氯以及内酰亚胺醚等的反应,制得5-H-1-芳基-1,2,3-连三唑[4,5-e]嘧啶-4-酮(2a-c)、5-N-甲基-1-芳基-1,2,3-连三唑[4,5-e]嘧啶-4-酮(3a-c)、1-芳基-4-乙氧羰基-5-脲基-1,2,3-连三唑(4a,b)、5-H-1-芳基-1,2,3-连三唑[4,5-e]嘧啶-4,6-二酮(5_(a,b))、1-苯基-1,2,3-连三唑[4,5-e]哌啶[1,2-b]嘧啶-4-酮(6a)、1-苯基-1,2,3-连三唑[4,5-e]氢化吖辛因[1,2-b]嘧啶-4-酮(7a),并经元素分析、红外、核磁共振以及质谱等方法确认了它们的结构,初步筛选了其代表特的生物活性.  相似文献   

9.
3-甲基-2-丁烯酸乙酯4经SeO2反式氧化,还原,溴化得到关键中间体4-溴-3-甲基-(2E)-丁烯酸乙酯7.7与三苯基胂反应生成季Seng盐8。二氢香茅醛与8在K2CO3-乙醇-微量水的存在下反应,得到(2E,4E)-3,7,11-三甲基-2,4-十二碳二烯酸乙酯1a及其(2Z,4E)-异构体1b,产率74%,该反应具有(4E)-立体选择性,同时C-2双键发生部分构型转化。  相似文献   

10.
首次合成了新显色剂2-(5-羧基-1,3,4-三氮唑偶氮)-5-二乙氨基酚(简称CTZAPN),研究了它的性质及其与铋显色反应的条件。结果表明:试剂的分子式C13H16N6O3分子量304.32,m.p. 252℃,各级酸离解常数为PKa1=3.1,PKa2=7.5,PKa=9.6;在PH 7的 NH4Ac介质中,试剂与铋形成紫红色络合物,λmax为 540 nm,对比度△λ为 120 nm,络合比Bi3+:R=1:2,摩尔吸光系数5.13 ×104L·mol-1·cm-1,Bi3+在0~1.8 mg/L范围内遵守比耳定律,在掩蔽剂的作用下,可不经分离直接测定合金样品及合成工业废水中微量铋,结果满意。  相似文献   

11.
本文用线性扫描二阶导数极谱法研究了酸性大红与各种环糊精的超分子体系;测定了它们的包结常数和包结比,比较了它们的包结能力,初步探讨了影响包结能力大小的可能因素。  相似文献   

12.
13.
Abstract

This study dealt mainly with the structure-reactivity relationship of selected organic inclusion compounds. The crystal structures of the inclusion compounds of three related hosts, 2,2′–bis(2,7–di-tert-butyl-9–hydroxy-9–fluorenyl)biphenyl, 2,2′–bis (2,7–dichloro-9–hydroxy-9–fluoienyl)biphenyl and 2, 2′–bis(2,7-dibromo-9–hydroxy-9–fluorenyl)biphenyl with 1,4–dioxane (Compound 1), 1,3–dioxane (Compound 2) and 1,3–dioxolane (Compound 3) respectively were elucidated, using single crystal X-ray crystallography. It was found that the guests were either located in channels or constricted channels (cavities), formed by the host framework. The kinetics of desolvation of these compounds were studied and their activation energies were compared.  相似文献   

14.
环状低聚糖──β-环糊精与胆红素包络作用的研究赵晓斌,何炳林(南开大学高分子化学研究所,天津,300071)关键词β-环糊精,胆红素,包络作用,环状低聚糖,包络化合物环糊精(CDs)是一类含6、7、8等数目的葡萄糖基单元通过α-1,4-糖苷键联结而成...  相似文献   

15.
活性艳红K-2BP与环糊精相互作用的电化学研究   总被引:3,自引:0,他引:3  
本文研究了活性艳红K-2BP的极谱伏安行为。实验表明:在0.1 mol/L的NaCl(pH 6.9)底液中,活性艳红K-2BP有一稳定、灵敏的还原峰。用线性扫描极谱法考察了活性艳红K-2BP与环糊精的相互作用,测定了活性艳红K-2BP与各种环糊精的包结比和包结常数;对不同类型环糊精的包结能力进行了比较;初步探讨了影响包结能力大小的可能因素。  相似文献   

16.
A novel method for the synthesis of N-monosubstituted aniline and its derivatives β-cyclodextrin(CD)host-guest complexes has been presented.The mild reaction gives the title compounds with high selectivity in good yields of 90-98%.  相似文献   

17.
α-, β-, and γ-Cyclodextrins are cyclic oligosaccharides consisting of six, seven, or eight glucose units, which can be obtained on a large scale from starch. They form inclusion compounds with smaller molecules which fit into their 5—8 Å cavity. These (crystalline) complexes are of interest for scientific research as, contrary to the classical clathrates, they exist in aqueous solution and can be used to study the hydrophobic interactions which are so important in biological systems. Cyclodextrins also serve as models both for polymeric starch and, in the form of their polyiodide complexes, for “blue iodine-starch”. As cyclodextrins catalyze several chemical reactions they and their functionalized derivatives provide useful enzyme models. Cyclodextrins can be used to advantage in the production of pharmaceuticals, pesticides, foodstuffs, and toilet articles—the (micro-encapsulated) active and aromatic substances enclosed within them are protected from the effects of light and atmosphere and can be easily handled and stored in powder from. Substances which are not very soluble in water become more soluble in the presence of cyclodextrins—creams and emulsions can be stabilized, and the growth and yield of grain harvests can be increased. Cyclodextrins can be chemically modified for many different purposes; polymerized cyclodextrin or cyclodextrin bound to a polymer carrier have already been employed in gel inclusion and affinity chromatography.  相似文献   

18.
A host-guest chemistry method for preparing both natural compounds and SHG inclusion crystal has been developed. The function moieties from the herb could be extracted effectively. The SHG crystal values showed that the host and guest compounds aligned as expected.  相似文献   

19.
Principal peculiarities of the use of phosphocontaining cyclodextrins as a new class of supramolecular structures are discussed. For the first time cyclodextrin perphosphite has been obtained and isolated in an individual state by the treatment of g -cyclodextrin with triazolide neopentylenephosphorous acid. Cyclodextrin perphosphite exhibited an unusual transphosphorylation under reaction with some chlorophosphites. The inclusion of adamantane into the cyclodextrin cavity results in slowing this reaction down. Some water-soluble cyclodextrin derivatives displayed high activity as phase transfer catalysts in biphase catalysis.  相似文献   

20.
实验部分1.试剂和仪器:FeCl_3·6H_2O AR;NaOH AR;PVA(聚乙烯醇)牌号PVA-124日本进口分装.UV分光光度计(日本UV-300);波长488nm激光束(COHERENT,innoVA 70);X射线光电子能谱(XPS)仪(沈阳Np-1型);红外光谱(IR)仪(美国PE-577);电子自旋共振(ESR)仪(西德ER-420). 2.试样制备:A:5%PVA水溶液;B:100ml pH=2的A含0.1克FeCl_3·6H_2O;C,D:100ml pH=7和13的A分别加入0.1克FeCl_3·6H_2O形成的红棕色透明溶液;E:试样D的  相似文献   

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