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1.
2,3-二氢-1,4-酞嗪二酮的微波合成   总被引:1,自引:0,他引:1  
李学华  涂光忠  安东各 《合成化学》2005,13(2):204-205,210
以邻苯二甲酸酐和肼类化合物为原料,用微波辐射合成了6种2,3-二氢-1,4-酞嗪二酮类化合物,其结构经^1H NMR和^13C NMR表征。  相似文献   

2.
尚志强  陈茹玉  黄有 《合成化学》2004,12(2):142-146
设计合成了一系列含氨基芳甲基膦酸酯的核苷衍生物,并研究了有关反应,产物结构经元素分析,IR,^1H NMR和^31P NMR证实,部分化合物作了抗肿瘤活性初步测定。  相似文献   

3.
一类含6个碳的长链叶立德经分子内Wittig反应,可合成含全氟烷基的多取代苯。反应产物经^1H NMR、^13C NMR、IR、MS等谱学分析方法的分析,确证了结构,同时研究了整个反应的可能历程。  相似文献   

4.
陈茹玉  程磊峰 《化学学报》1990,48(7):726-730
本文报道了七个新的2,4,5-三氧-1,3,2,4-二氮二磷杂环戊烷衍生物的制备, 产物的结构经IR, ^1H和^31P NMR, MS以及元素分析证实, 并利用^31P NMR和GC-MS区分了化合物的顺式和反式异构体。  相似文献   

5.
3,6-双(1氢-1,2,3,4-四唑-5-氨基)-1,2,4,5-四嗪的合成与表征   总被引:13,自引:2,他引:11  
岳守体  阳世清 《合成化学》2004,12(2):164-166
研究了低感度高氮化合物3,6-双(1氢-1,2,3,4-四唑-5-氨基)-1,2,4,5-四嗪的合成,其结构经元素分析,IR,^1H NMR和^13C NMR表征。  相似文献   

6.
从壬二酸、癸二酸和十一碳烯酸出发,经脱羰端烯化反应、Wacker反应制备了2,6-康二酮,2,7-辛二酮,2,9-苯二酮。所得化合物的结构经IR,^1H NMR,^13C NMR和MS证实。  相似文献   

7.
3,3’-偶氮-(6-氨基-1,2,4,5-四嗪)的合成与表征   总被引:1,自引:0,他引:1  
以硝酸胍和水合肼为原料,经7步反应合成了高氮含能化合物3,3'-偶氮-(6-氨基-1,2,4,5-四嗪),其结构经^1H NMR,^13C NMR,IR及元素分析表征。  相似文献   

8.
环己二胺类手性席夫碱配体的合成与表征   总被引:1,自引:1,他引:0  
以(R,R)-1,2-环己二胺为手性源,同水杨醛及带有叔丁基,溴或硝基的取代水杨醛反应合成了5个手性席夫碱配体。其结构经^1H NMR,^13C NMR,IR和MS表征,并测定了其熔点和比旋光度。  相似文献   

9.
从L-酩氨酸乙酯出发,经氨基保护、硝化、还原反应制得3-氨基-L-酪氨酸乙酯(4);4与苯甲醛或取代苯甲醛完成环化反应,合成了6个新的含苯并嗯唑的L-酪氨酸衍生物,其结构经^1H NMR,^13C NMR,IR和元素分析表征。  相似文献   

10.
4-二甲氨基吡啶催化合成含氟苯甲酸糖酯   总被引:5,自引:1,他引:5  
以4-二甲氨基吡啶为催化剂由含氟苯甲酸与溴代乙酰糖催化酯化合成了4个新的含氟苯甲酸糖酯。其结构经IR,^1H NMR和MS确认,多数还作了^13C NMR测定。  相似文献   

11.
以2-吡咯烷酮为起始原料,经成盐与缩合反应合成了乙拉西坦,总收率60.2%.其结构经1H NMR, IR和MS确证.  相似文献   

12.
This paper presents two distinct methods for the determination of the solid–solid transition temperature (Ttr) separating the temperature ranges of stability of two crystallographic forms, hereafter called morphs, of a same substance. The first method, based on thermodynamic calculations, consists in determining Ttr as the temperature at which the Gibbs free energies of the two morphs are equal to each other. For this purpose, some thermodynamic characteristics of both morphs are required, such as the specific heat capacities, the melting temperatures and the melting enthalpies. These are obtained using the Differential Scanning Calorimetry (DSC). In the second method, Ttr is determined directly by an experimental study of the temperature ranges of stability of each morph. The three main originalities of the method developed are (i) to prepare samples composed by an isomassic mixture of crystals of both morphs, (ii) to set them in a thermostated and agitated suspension, and (iii) to use an in situ Raman spectroscopic probe for the determination of the crystallographic form of the crystals in suspension at equilibrium. Both methods are applied to determine the solid–solid transition temperature of the enantiotropic system of Etiracetam, and both of its two crystallographic forms so far identified, named morph I and morph II. The first method is shown to be very sensitive to the experimental data obtained by DSC while the second experimental method is a more accurate, precise, time- and effort-friendly method for the determination of Ttr. The solid–solid transition temperature of the Etiracetam system, determined with the second method, using three different solvents, is found to be equal to 303.65 K ± 0.5 K.  相似文献   

13.
This article focuses on the development of an innovative method, based on thermodynamic considerations and with the use of Differential Scanning Calorimetry (DSC), for the estimation of the melting enthalpy of crystalline compounds which are metastable near their melting temperature. The curves obtained, at various heating rates, are analysed in two steps. In the first step, the area of a zone generated by the melting endothermic peak is calculated following a specific method. In the second step, the melting enthalpy is extracted from this area through an enthalpy balance. This method is applied to both identified crystallographic forms, named form I and form II, respectively, of Etiracetam (UCB Pharma). The results show that the melting enthalpy of the stable form II compare well with the ones obtained using conventional methods. The curves of the metastable form I present thermal instabilities (partial solid–solid polymorphic transition and beta-recrystallization) near the form I melting peak leading to difficulties for a direct determination of the melting enthalpy by conventional methods. The proposed method is therefore very useful for the estimation of the form I melting enthalpy.  相似文献   

14.
应用JEOL FX-90Q NMR谱仪测定了吸附在NaY分子筛,氧化铝,二氧化硅上的四甲基硅烷和正己烷的核磁氢谱和碳谱.结果表明,在一些吸附体系的研究中,现有仪器适用于液体样品,以氢谱和碳谱比较发现碳谱在分辨率分方面较之氢谱有几个优点,顺磁杂质对谱线宽度有明显影响.在NaY分子筛上预先吸附氢以后再吸附乙烯,其吸附速率低于未吸附氢的样品.  相似文献   

15.
苯乙烯-马来酸酐共聚物的核磁共振分析   总被引:1,自引:0,他引:1  
利用^1H NMR、^13C NMR及DEPT(无畸变极化转移增强)核磁共振技术研究了苯乙烯-马来酸酐共聚物(SMA)的序列结构和组成,并比较了几种核磁共振实验技术对分析SMA结果的准确性;实验表明^1H NMR是分析组成的简单、快速而有效的方法,DEPT谱进行序列结构计算准确度较高。  相似文献   

16.
以邻溴苯酚为起始原料,经硅基化、水解和酯化反应得到苯炔前体邻-三甲硅基苯酚三氟甲磺酸酯,总收率75%。其结构经1HNMR,13CNMR,19FNMR和IR表征。  相似文献   

17.
以3-氨基-4-酰氨肟基呋咱为原料,经重氮化和叠氮化反应合成了新化合物3-叠氮基-4-酰氯肟基呋咱(3),总收率67%.其结构经1H NMR,13C NMR,15N NMR,IR及元素分析表征.热失重法研究结果表明,3具有良好的热稳定性.  相似文献   

18.
H2SO4-SiO2固体酸的结构及酸性研究   总被引:2,自引:0,他引:2  
以溶胶-凝胶法制备了H2SO4-SiO2固体酸催化剂,并对其结构和酸性进行了系统表征.FT—IR和^29Si—NMR结果表明H2SO4和SiO2间存在相互作用,因此硫酸与硅胶形成稳定的固体、XRD、SEM和TEM结果表明,H2SO4-SiO2固体酸是一多孔无定型材料;BET法测定的H2SO4-SiO2固体酸的比表面积和孔体积结果表明,随着H2SO4与SiO2质量比增加,其比表面减少,孔体积增大;H2SO4-SiO2固体酸的酸强度和液体浓硫酸相当,酸强度与干燥温度和H2SO4加入量有关,固体酸的这一性质以^1H—MAS NMR进行了系统的表征.  相似文献   

19.
杨明蓉  唐卓  陈应春 《合成化学》2012,20(3):331-333,345
以生物素,4,4’-二甲氧基三苯基氯甲烷,6-氨基-1-己醇,2-氰基乙氧基-双(N,N-二异丙基)亚磷酰胺等为原料,采用改进方法合成了生物素标记试剂——[1-N-(4,4’-二甲氧基三苯甲基)-生物素-6-氨基己基]-2-氰乙氧基-N,N-二异丙基亚磷酰胺(3),总收率51.0%,其结构经1H NMR,13C NMR,31P NMR和MS确证。通过固相亚磷酰胺三酯法,应用3合成了一段含有十个碱基的5’-端生物素标记的寡核苷酸链,其结构经MS确证。  相似文献   

20.
The solution structure of the Pd(II) complex of mn-12-S4 was studied in detail by NMR spectroscopy. The stoichiometry of the complex was determined by 1H NMR titration experiments. 3J(H,H) coupling constants were extracted from the 2D J-resolved NMR spectrum of the complex providing information concerning the S-C-C-S torsional angles. Further conclusions about the conformation of [Pd(mn-12-S4)](BF4)2 were drawn from experimental NOEs. The results of the NMR study were corroborated by molecular modelling.  相似文献   

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