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1.
2-甲氧基-3-氟-4-碘吡啶是一个重要的医药化工中间体,其合成路线未见文献报道。以2-甲氧基-3-氟-5-氯吡啶为起始原料,经氢解和碘代两步反应合成标题化合物,总收率62.8%,其结构经1H NMR, 13C NMR和MS确证。  相似文献   

2.
以3-氨基吡嗪-2-羧酸为原料,经酯化反应、亲电反应和重氮化反应合成了3-氟-6-碘吡嗪-2-羧酸甲酯(1),总收率62.34%,其结构经1H NMR、13C NMR和MS确证,用X-单晶衍射法测定了化合物的晶体结构。结果表明:1(CCDC: 1986368)属单斜晶系,空间群C2/c,晶胞参数a=17.6566(5) Å, b=4.74850(10) Å,c=19.6368(6) Å,β=95.6540(10)°,V=1638.39(8) Å3,Z=8,Rgt(F)=0.0173,wRref(F2)=0.0465,F(000)=1056,μ=3.885 mm-1  相似文献   

3.
以可再生性D-氨基葡萄糖为底物,在甲醇-三乙胺体系中,以苯甲酰氯作为酰化试剂,经选择性N-酰化反应合成得到N-苯甲酰基-D-氨基葡萄糖,继续在硼酸催化下,转化为3-苯甲酰胺基-5-乙酰基呋喃,两步一锅煮总产率则为44%,其结构经1H NMR,13C NMR, IR和MS(ESI)确证。   相似文献   

4.
以2,4,5-三氟苯乙酸为起始原料,经氯化和酰化反应得2-氰基-3-羟基-4-(2,4,5-三氟苯基)丁-2-烯酸乙酯(2); 2经水解脱羧合成了3-氧代-4-(2,4,5-三氟苯基)丁腈,总收率61.5%,纯度97.6%,其结构经1H NMR和MS(ESI)确证。  相似文献   

5.
以4-氟肉桂酸为原料,依次经过硫酸氢钾氧化、开环加成和乙酸酐催化反应,合成了一种新型的醛糖还原酶抑制剂1-乙酰基-5-苯基-(4-氟)-1H-吡咯-3-基乙酸酯(4-F-APPA),总收率51%,纯度大于98%,其结构经1H NMR, 13C NMR, IR和MS(ESI)表征。并研究了4-F-APPA的抑制活性。结果表明:4-F-APPA的IC50为7.2×10-2 μM,优于阳性对照药依帕司他。  相似文献   

6.
直接法硝解乌洛托品制备黑索今的过程中合成了一种新型的环形副产物,采用硅胶柱层析法分离得到3, 5-二硝基-1-氧-3, 5-二氮杂环己烷,洗脱剂为:丙酮/二氯甲烷,梯度洗脱.以丙酮为溶剂培养得到了3, 5-二硝基-1-氧-3, 5-二氮杂环己烷单晶,用元素分析、傅里叶变换红外(FTIR)光谱、核磁共振氢谱(NMR)以及质谱(MS)对其结构进行了表征,用X射线单晶衍射仪测定了其晶体结构.结果表明,晶体C3H6N4O5分子量为178.12,属于单斜晶系,空间群P121/n1,晶胞参数: a = 0.58128(13) nm, b = 1.72389(14) nm, c = 0.71072(6) nm, β =112.056°, V = 0.66006(16) nm3, Z = 4, DC= 1.792 g·cm-3, μ = 0.17 mm-1, F(000) = 368.0,最终偏差因子R =0.0397.用同步热分析仪技术研究了3, 5-二硝基-1-氧-3, 5-二氮杂环己烷的热行为, DSC曲线上在383.15和519.05 K分别有一个尖锐的熔化吸热峰和分解放热峰.另外,根据Kissinger方程及Flynn-Wall-Ozawa方程和不同升温速率下的TG曲线计算得到了该化合物的热分解动力学参数(活化能和指前因子),利用Coats-Redfern法研究了该物质的热分解机理.结果表明: 3, 5-二硝基-1-氧-3, 5-二氮杂环己烷是一种低熔点、热稳定性好的化合物. Kissinger方程计算其活化能为212.32 kJ·mol-1,指前因子为6.20×1020 s-1, Flynn-Wall-Ozawa方程计算其活化能为210.39 kJ·mol-1,该物质的热分解动力学方程为G(α) = (1-α)-1-1,反应级数为2.  相似文献   

7.
5,6,7,8-四氢喹啉及衍生物是医药和农药的重要中间体。2-羟基-5,6,7,8-四氢-5,8-亚甲基喹啉-3-羧酸是合成HIF脯氨酰羟化酶抑制剂的重要中间体,其合成方法目前无文献报道。本文以降冰片烯为起始原料,经水合、氧化、缩合、环合和水解5步反应合成目标产物,总收率43.09%,结构经1H NMR、 13C NMR和MS确证。该路线具有原料廉价易得、操作简单、后处理方便且收率较高等优点,适合工业化生产。  相似文献   

8.
3-芳氧基-6-取代哒嗪的合成及其除草活性   总被引:4,自引:0,他引:4  
合成了系列3-芳氧基-6-取代哒嗪类化合物.化合物结构经1HNMR、元素分析、IR和MS确证.生物活性测试结果表明,该类化合物具有很好的除草活性,讨论了其结构与除草活性的关系.  相似文献   

9.
常宝  乌云 《合成化学》2018,26(6):425-428
以3-卤氧化吲哚和吗啉(或硫代吗啉)为起始原料,碳酸钠为催化剂,于60 ℃发生3-叔胺基化反应,合成了10个新型的3-吗啉四取代氧化吲哚 (3aa~3bh),收率86%~94%,其结构经1H NMR, 13C NMR和HR-MS(ESI-TOF)表征。  相似文献   

10.
以2-乙氧基乙胺和3-氯-1-丙醇等为起始原料, 经7步反应, 制备了N,N-二[二(3-甲氧基丙基)膦基乙基]-2-乙氧基乙胺(PNP5)盐酸盐, 其中关键步骤是后两步. PNP5盐酸盐的结构和组成通过IR, 1H NMR, 13C NMR, 31P NMR, MS和元素分析等方法确认.  相似文献   

11.
Zusammenfassung Mo3CoB3, Mo3NiB3, W3CoB3 und W3NiB3 kristallisieren in einem eigenen Typ (W3CoB3-Struktur). Das trigonal prismatische Bauelement [T 6B]* ist zu Ketten vereinigt, wobei B3-Gruppen entstehen. Die Phasen sind vermutlich Bor-reicher als obiger Formel entspricht.
The crystal structure of W3CoB3 and the isotypic phases Mo3CoB3, Mo3NiB3, and W3NiB3
Mo3CoB3, Mo3NiB3, W3CoB3, and W3NiB3 were found to possess a new type of crystal structure (W3CoB3-structure type). Trigonal prismatic groups [T 6B]* are linked together forming chains in such a way that B3-groups occur. These borides do probably exist with a larger amount of boron as to compared with the formula.


Mit 2 Abbildungen  相似文献   

12.
γ-Nitro-γ-butyrolactone By oxidation of 3-(1-nitro-2-oxocyclohexyl)propanal ( 1 ) with KMnO4, besides 3-(1′-nitro-2′-oxocyclohexyl)pripionic acid ( 2 ), the complete hydrolysis product 4-oxononanedioic acid ( 4 ) and the oxidized semi-hydrolysis product 5-(2-nitro-5-oxotetrahydro-2-furyl)pentanoic acid ( 3 ) were formed. The crystalline 3 decomposes at r.t. forming 4 and nitrous gases; its structure was established by X-ray determination.  相似文献   

13.
γγγ-Trifluorocarbonyl compounds are easily obtained in a good yield by introduction of the 1,1,1-trifluoroethyl moiety (CF3-CH2-) on the -methylene group of a ketone.  相似文献   

14.
K3SbSe3, Rb3SbSe3, and Cs3SbSe3 – Synthesis and Crystal Structure The compounds K3SbSe3, Rb3SbSe3 and Cs3SbSe3 were synthesized by heating mixtures of Sb2O3 and an alkalicarbonate in a stream of hydrogen saturated by selenium in a temperature range between 750 °C and 800 °C. The compounds crystallize isostructural with Na3AsS3. A comparison of atomic distances and bond angles with those of the isostructural arsenic and bismuth compounds shows the effect of lone pairs.  相似文献   

15.
Thin films of methylammonium lead halides, CH3NH3PbI3 and CH3NH3PbI3-xClx, were deposited onto symmetrical microstructured electrode arrays of gold or platinum on Si/SiO2 wafers. Polarization studies were carried out on perovskite films under vacuum in the dark. For poling, a constant voltage was applied to the samples while the temperature was cycled between 295 K and 4 K. The measured current densities depending on the temperature showed distinct characteristics relating strongly to the crystal phase and the dielectric properties of the perovskite films. Voltage sweeps were carried out at different scan rates at specific temperature intervals after poling. The polarization of the films due to the migration of iodide vacancies in direction of the blocking perovskite/metal interface was frozen almost up to room temperature. Charge carriers were only able to cross the blocking barrier and contribute to the current where the ions have accumulated during poling. All J-V curves showed hysteresis: inverted and regular hysteresis at room temperature and below, respectively. Inverted hysteresis originates from the slow accumulation of ions at the blocking barrier, while regular hysteresis arises from a distortion in the adjacent crystals which will be discussed.  相似文献   

16.
The synthesis of derivatives of 3-amino-3-deoxy-L-erythrose by LAH or LAD reduction of the oxime of 1,2-O-isopropylidene α-L -glycero-tetros-3-ulofuranose is described.  相似文献   

17.
K3BiSe3, Rb3BiSe3, and Cs3BiSe3 – Derivatives of the Th3P4 Structure Type The compounds K3BiSe3, Rb3BiSe3, and Cs3BiSe3 were synthesized by heating mixtures of Bi2O3 and the respective alkalicarbonate in a stream of hydrogen saturated by selenium at 850°C. Thin crystals of the compounds appear red in transmitted light. They crystallize isostructural with Na3AsS3, space group P213, lattice constants a = 9.771(5) Å, a = 10.161(3) Å, and a = 10.587(5) Å for K3BiSe3, Rb3BiSe3, and Cs3BiSe3, respectively. The Na3AsS3 structure type is a derivative of the Th3P4 structure type.  相似文献   

18.
Zusammenfassung Es wurden die Enthalpien der Reaktionen von AsCl3, AsBr3, AsJ3, SbCl3, SbBr3 und SbJ3 mit Tributylphosphat, N,N-Dimethylacetamid und Hexamethylphosphorsäuretriamid bestimmt. Das Verhalten der Addukte bei Gegenwart eines Überschusses der Donoren wird beschrieben.
Acceptor properties of AsCl3, AsBr3, AsI3, SbCl3, SbBr3, and SbI3
The enthalpies of the reactions of AsCl3, AsBr3, AsI3, SbCl3, SbBr3 and SbI3 with tributylphosphate, N,N-dimethylacetamide and hexamethylphosphoric acid triamide were measured. The behavior of the adducts in the presence of excess donor molecules is described.


Mit 5 Abbildungen  相似文献   

19.
Condensation of pyrrole-2-dithiocarboxylates with CH acids containing ester groups, in the KOH-DMSO system, was used to prepare previously unknown 1-alkylthio-3H pyrrolizin-3-ones. The latter, treated with secondary amines, are readily converted to the corresponding 1-amino derivatives.  相似文献   

20.
Previously unknown 1-alkylthio-3H-pyrrolizin-3-ones have been obtained by the condensation of pyrrole-2-dithiocarboxylates with CH acids containing ester groupings in the KOH-DMSO system. On treating the products with secondary amines they are readily converted into the corresponding 1-amino derivatives.Irkutsk Branch of the Russian Academy of Sciences, Irkutsk 664033. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 919–924, July, 1996. Original article submitted May 2, 1996.  相似文献   

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