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1.
以2-乙酰呋喃为起始原料,经扩环、甲基化、去质子化、亲核加成、缩酮化、Rh/C催化氢化及水解等反应合成了常山酮中间体--1-(3-甲氧基哌啶-2-基)丙酮,总收率40.2%,其结构经1H NMR和ESI-MS确证。  相似文献   

2.
光(热)致变色剂:单和双吲哚啉螺苯并吡喃   总被引:5,自引:0,他引:5  
用乙醇作溶剂,在哌啶存在下,通过2,3,3-三甲基-N-(β-羟乙基)吲哚啉碘化物(1)与3-或5-硝基水杨醛反应,分别制得螺环异构体(2a)与(2b)。它们再进一步与异氰酸苯酯进行加成反应,合成一对单螺环异构体(3a)与(3b),将2a 与2b 分别和2,4-二异氰酸甲苯酯(TDI)反应,合成一对双螺环异构体(4a)与(4b)。2a,3a,4a,4b 是光致变色化合物;2b 与3b 是热致变色化合物。  相似文献   

3.
郑啸  陈果  阮源萍  黄培强 《中国科学B辑》2009,39(10):1175-1183
合成了(S)-3-羟基哌啶苯硫醚化合物6作为3-羟基哌啶氮α-碳负离子手性合成子(B)的合成等效体.化合物6经羟基去质子现场保护、萘锂(LN)还原锂化形成手性哌啶醇双负离子中间体B.双负离子B可被质子淬灭得到还原产物2a 而与羰基化合物反应则得到α-羟烷化产物12~17和少量还原产物2a.该反应具有很高的环上2,3-位非对映立体选择性 与非对称的羰基化合物反应产生新手性中心的立体选择性从50:50到77:23.  相似文献   

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丙烯酸乙酯与哌啶经加成反应制得3-(1-哌啶基)丙酸乙酯(1);1与格氏试剂苯基溴化镁反应制得普立地诺(2);2与甲磺酸反应合成了普立地诺甲磺酸盐,总收率70.3%,其结构经1H NMR,13C NMR和MS确证。  相似文献   

5.
将4-(2-羟乙基)哌啶蒸汽在425 ℃下通过CNM-3型固体酸催化剂进行分子内脱水反应,一步合成了目的产物1-氮杂环[2.2.2]辛烷(奎宁环),4 h内25 g 4-(2-羟乙基)哌啶蒸汽单程收率可达76.8%,最高收率84.3%。 该方法原料易得,适合于奎宁环的工业化制备。  相似文献   

6.
本文以SO_4~(2-)/ZrO_2-NiO/Al_2O_3固体超强酸为催化剂,以1,5-戊二醇和氨水为原料,经固定床反应器合成了哌啶。研究原料的摩尔配比,反应温度,以及原材料进料速度对合成反应的影响;实验结果表明合成哌啶的最优实验方案为:氨水与1,5-戊二醇原料物质的量之比为13∶1,反应温度为380℃,进料速度为1.0 mL·min~(-1),哌啶的收率最高达到95.2%。  相似文献   

7.
以2-(2-硝基苯氧基)-1-溴乙烷或3-(2-硝基苯氧基)-1-溴丙烷为原料分别在氢化钠作用下与N-Boc-4-羟基哌啶反应,得到了与预期结构不同的产物.该产物的结构经1H NMR,13C NMR,LC-MS分析表明,其并非为原料2-(2-硝基苯氧基)-1-溴乙烷与N-Boc-4-羟基哌啶发生Williamson反应生成预期的混合醚,而是芳环上的烷氧基被取代的异常产物.根据这个实验结果,推测上述反应的可能机理是发生了芳环上的亲核取代反应.  相似文献   

8.
以Boc-4-哌啶甲醇为起始原料,经Swern氧化、羟醛缩合、Knorr吡咯合成法、氨基保护、酯水解、酰胺化、脱保护及成盐反应合成了一系列4-(哌啶-4-基)-1H-吡咯-3-甲酰胺类衍生物盐酸盐,经~1H NMR,~(13)C NMR和MS-ESI等确证结构。用抑菌环法测试了此类衍生物对大肠杆菌和金黄葡萄球菌生长的抑制作用,结果显示目标化合物能够不同程度地抑制大肠杆菌的生长,其中4-(哌啶-4-基)-1H-吡咯-3-(N-甲基-N-丙基甲酰胺)盐酸盐对大肠杆菌的抗性显著,最高抑制率达96%。  相似文献   

9.
尤学艳  周翼  姚成 《合成化学》2011,19(3):412-414
以乙酸和哌啶为催化剂,在正丁醇中通过4-(N,N-二乙氨基)水杨醛与硝基乙酸乙酯的缩合反应合成了3-硝基-7-(N,N-二乙基)香豆素(2);2经SnCl2/HCl还原制得3-氨基-7-(N,N-二乙基)香豆素(3);3与芳香醛反应合成了六个新的香豆素类Schiff碱,其结构经UV,1H NMR和MS表征.  相似文献   

10.
黄斌  程德军 《合成化学》2015,23(1):88-91
以5-溴水杨醛和4-氯苄氯为原料,通过消去、还原及溴化反应制得中间体4-溴-2-溴甲基-1-[(4-溴苄基)氧]苯(3);哌啶-4-酮经Boc保护、还原等4步反应制得中间体N-乙基-N-(4-哌啶基)吡啶甲酰胺(7);3与7通过消去反应合成了一种新型CCR5拮抗剂——N-【1-{5-溴-2-[(4-氯苄基)氧基]苄基}-4-哌啶基】-N-乙基吡啶甲酰胺,其结构经1H NMR,13C NMR和ESI-MS表征。  相似文献   

11.
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988.  相似文献   

12.
利用手持技术改进测定乙醇分子结构实验   总被引:1,自引:0,他引:1  
利用压强传感器代替排水集气法,改进测定乙醇分子结构实验的仪器装置,并探索最佳反应条件。另外,设计两个空白实验,结合压强变化曲线对实验误差进行相关讨论。  相似文献   

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由于石化行业的生产需要,其材质的使用具有多样性和广泛性,经常会出现顾客委托的测试样品的一个或几个元素跨越光谱仪现有测试程序测量范围的情况。本法通过对光谱仪测试原理的认识,根据光谱仪的测试能力及标样的采集,实现了一个或几个元素测量范围的扩展,并对其测量的影响因素进行了研究。  相似文献   

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Theoretical and Experimental Chemistry - The effect of the method of modification of catalysts based on zeolite X by cesium and magnesium cations (ion exchange and impregnation) on the selectivity...  相似文献   

17.
The oxygen quenching rate constants for singlet and triplet excited states of the dimethyl ester of mesoporphyrin IX increase with decreasing viscosity of the medium and reach a maximum at a viscosity of approximately 0.4 mPa·sec, after which the rate constants begin to decrease. The drop in rate constant with increasing fluidity of the medium may be related to a nonequilibrium character of the elementary act in the interaction of the reactants in the solvent cage. In viscous media such as isopropyl alcohol, isobutyl alcohol, and isoamyl alcohol, the reaction radius is greater than the sum of the radii of the reacting particles. The long-range character of these processes is due to the relatively weak dependence of the quenching probability on distance.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 2, pp. 161–167, March–April, 1989.  相似文献   

18.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

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