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《化学研究》2017,(2)
以4-溴苯乙酮、靛红及常见试剂为起始原料,通过Pfitzinger reaction、羧基酯化、钯催化、水解等反应合成2-(4-二羟基硼烷)苯基喹啉-4-羧酸(PBAQA).二胺化合物经二碳酸二叔丁酯单保护、酰胺缩合、盐酸脱保护基,再与另一端苯基硼酸化合物酰胺缩合,合成了3个含有PBAQA结构的二硼酸新化合物,考察了溶剂选择、反应温度、活化反应时间以及反应中羧基化合物与1,3-二环己基碳化二亚胺(DCC)和1-羟基苯并三唑(HOBT)物质的量之比对二硼酸类化合物收率的影响.通过IR、~1H NMR、~(13)C NMR、HRMS对新化合物的结构进行表征.结果表明最佳反应条件为以N,N-二甲基甲酰胺(DMF)作溶剂,反应温度20℃,活化反应60 min,反应中羧基化合物与DCC和HOBT的物质的量之比在1∶20∶20的条件下,收率可达82%,纯度90%.该合成路线具有操作步骤简便,经济适用,副产物少易于纯化等特点,对二硼酸化合物衍生化研究具有重要实用和经济价值. 相似文献
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研究了一条新的路线用于他汀类药物的重要中间体(R)-4-氰基-3-羟基丁酸乙酯的合成. 以廉价、易得的L-(-)-苹果酸为起始原料, 经酯化、还原、溴代和氰化四步反应得到目标化合物(R)-4-氰基-3-羟基丁酸乙酯, 合成总收率为56.7%. 所有中间体和最终产物均由ESI-MS, 1H NMR和13C NMR光谱及比旋光度表征并与文献值比较. 该方法原料易得、操作简便、收率良好, 产物容易分离纯化, 是一条适合大规模制备(R)-4-氰基-3-羟基丁酸乙酯的新合成工艺路线. 相似文献
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以卤代芳烃为原料,经硼酸化反应和Suzuki偶联反应合成了一系列三芳基-2-硼酸化合物,收率67.4%~70.1%,纯度均98%,其结构经1H NMR和元素分析确证。 相似文献
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The new compound 1,4,7,10-tetrakis-(2-(2,3-difluorophenyl) ethyl) -1,4,7,10-tetra-zacyclododecane 2 has been synthesized and structurally characterized by single-crystal X-ray diffraction. The molecule turned into diamond crystals grown from CH3CN by slow diffusion at room temperature. It crystallizes in the triclinic system,space group P1 with a = 9.543(2) ,b = 10.507(3) ,c = 10.734(3) ,α = 60.979(3) ,β = 81.870(4) ,γ = 84.279(4) o,V = 931.1(4) 3,Z = 1,Dc = 1.307 g/cm3,C40H44F8N4,Mr = 732.79,F(000) = 384,μ = 0.105 mm-1,T = 296(2) K,MoKa radiation(λ = 0.71073) ,R = 0.0494 and wR = 0.0989 for 1589 observed reflections with I > 2σ(I) . Hydrogen bonds and C-H···π stacking interactions in 2 contribute to a supramolecular structure. Moreover,compound 2 has been determined by 1H NMR,13C NMR,MS,IR spectra and elemental analysis. 相似文献
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A novel molecule tetra-N-alkylation of cyclen (1,4,7,10-tetraazacyclododecane), 1,4,7,10-tetrakis(2-((4-hydroxy)phenoxy)ethyl)-1,4,7,10-tetraazacyclododecane 2, was synthesized and structurally characterized by single-crystal X-ray diffraction. The molecule turned into chiral helical compound crystals grown from EtOH by slow diffusion at room temperature and three of the four hydroquinone groups of the benzene ring formed a g-electron-rich cavity by C-H…π stacking interaction. The crystal belongs to the monoclinic system, space group P21/C with a = 13.9192(9), b = 13.2871(6), c = 22.1894(15)A^°, β = 91.4600(10)°, V = 4102.5(4)A^°3, Z = 4, Dc = 1.219 g/cm^3, C40H52N4O8, Mr = 752.89, F(000) = 1616,μ = 0.088 mm^-1, MoKa radiation (λ = 0.71073), R = 0.0578 and wR = 0.1389 for 5588 observed reflections with I 〉 2σ(I). Moreover, compound 2 was characterized with ^1H NMR, ^13C NMR, IR spectra and MS. 相似文献
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N,N',N",N"'-四对甲苯碘酰-1,4,7,10-四氮杂环十二烷的微小常压快速水解 总被引:5,自引:0,他引:5
N,N',N",N"'-四对甲苯磺酰-1,4,7,10-四氮杂环十二烷是Atkins法合成1, 4,7,10-四氮杂环十二烷的关键中间体,但其水解脱磺酰基比较困难,常规水解 一般需要采用96%-98%硫酸在140 ℃左右加热2-3d。报道了一种微波促进快速水解 法,即在稍加改装或未改装的家用微波炉中,采用95%-98%硫酸,控制火力2-5档, 全对甲苯碘酰化全氮冠醚仅需50-120 s即可完成水解,比常规加热水解所需时间缩 短约3000-8000倍,浓硫酸用量也比常规加热水解少,收率较常规水解高。 相似文献
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[reaction: see text] An efficient route to deoxyadenosine derivatives labeled on both the amino group and nitrogen 1 is uncovered. First, 3',5'-di-O-acetyl-2'-deoxy-1-(2-nitrobenzenesulfonyl)inosine (2a) and only 1.1 equiv of (15)NH4Cl are used for labeling position 1 (1a) through the isolation of the open intermediate and its cyclization with DBU in anhydrous CH3CN. Inosine 1a is then converted to [N,1-(15)N2]-3',5'-di-O-acetyl-N6-benzoyl-2'-deoxyadenosine (5a, the precursor of 6a) via a Pd/dppf-catalyzed chloride-to-benzamide replacement, by using again only 1.1 equiv of the labeling source. 相似文献
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N,N′,N",N"'-四对甲苯磺酰-1,4,7,10-四氮杂环十二烷的微波常压快速水解 总被引:2,自引:0,他引:2
N,N′,N",N"'-四对甲苯磺酰-1,4,7,10-四氮杂环十二烷是Atkins法合成1,4,7,10-四氮杂环十二烷的关键中间体,但其水解脱磺酰基比较困难,常规水解一般需要采用96%~98%硫酸在140℃左右加热2~3 d.报道了一种微波促进快速水解法,即在稍加改装或未改装的家用微波炉中,采用95%~98%硫酸,控制火力2~5档,全对甲苯磺酰化全氮冠醚仅需50~120s即可完成水解,比常规加热水解所需时间缩短约3000~8000倍,浓硫酸用量也比常规加热水解少,收率较常规水解高. 相似文献
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Infrared spectra of hydrogen-carbonyl sulfide clusters containing paraH2, orthoH2, or HD have been studied in the 2060 cm(-1) region of the C-O stretching vibration. The clusters were formed in pulsed supersonic jet expansions and probed using a tunable infrared diode laser spectrometer. Simple symmetric rotor type spectra were observed and assigned for clusters containing up to N = 7 hydrogen molecules. There was no resolved K structure, and Q-branch features were present for orthoH2 and HD but absent for paraH2. These characteristics can be rationalized in terms of near symmetric rotor structures, very low effective rotational temperatures (0.15 to 0.6 K), and nuclear spin statistics. The observed vibrational shifts were compared with those from recent observations on the same clusters embedded in helium nanodroplets. The observed rotational constants for the paraH2 clusters are in good agreement with a recent quantum Monte Carlo simulation. Some mixed clusters were also observed, such as HD-HD-He-OCS and paraH2 - orthoH2 - OCS. 相似文献
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Yu. M. Polikarpov F. I. Bel'skii S. A. Pisareva M. I. Kabachnik 《Russian Chemical Bulletin》1989,38(9):1945-1949
The synthesis is described and the mechanism of acid dissociation is found by31P NMR spectroscopy. Stability constants for a large number of cations are determined. A high selectivity for complexation toward Cu2+, Zn2+, Cd2+, and Hg2+ ions is found.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2112–2116, September, 1989. 相似文献
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Douglas X. West Amy M. Stark Gordon A. Bain Anthony E. Liberta 《Transition Metal Chemistry》1996,21(4):289-295
Summary The title complexes of general formula [Cu(HL)Cl2] or [Cu(L)Cl] have been isolated and characterized by 1H and 13C-n.m.r., i.r. and electronic spectra. The i.r., electronic and e.s.r. spectral data for the CuII complexes are compared with those of previously studied complexes. The antitumour and antiviral activities of the thiosemicarbazones and their complexes are discussed. 相似文献