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1.
报道了以钯(Ⅱ)为催化剂的咔唑分子间直接乙酰氧基化反应的通用高效方法。以醋酸钯为催化剂,过硫酸钾为氧化剂,2-吡啶磺酰基作为导向基团,以85%和83%的收率合成单乙酰氧基化和双乙酰氧基化产物。结构经~1H NMR,~(13)C NMR,IR和HR-MS(ESI)表征。  相似文献   

2.
林玲  林学然  冯鹏举 《合成化学》2020,28(7):626-631
5-硝基嘧啶作为导向基(DG)能很好的辅助钯催化苯酚邻位乙酰氧基化,研究发现该导向基的引入方且偶联后能在温和条件下移除。该方法操作简单,有良好的底物官能团兼容性,通过一锅法实现导向基的引入和苯酚邻位乙酰氧基化,合成了具有丰富取代基的10种2-[(5-硝基嘧啶-2-基)氧基]芳基乙酸酯新化合物。该类乙酰氧基化产物能够以最高75%收率得到,其结构均经1H NMR, 13C NMR以及HR-MS(ESI)确证。   相似文献   

3.
以醋酸钯、1,1’-联萘-2,2’-双二苯膦(BINAP)为催化剂,二甲苯为溶剂,氟代偕二醇砌块在碳酸钾的作用下,脱三氟乙酸后与溴代芳烃发生芳基化反应,于130℃反应7 h,合成了一系列α-氟代芳基酮类化合物,收率最高可达96%,其结构经1H NMR,13C NMR,19F NMR和HR-MS(ESI)表征。  相似文献   

4.
巨新春  张群  孙淑婷  王博 《合成化学》2019,27(6):411-417
以邻苯二胺为配体,制备了一种新型的纳米钯催化剂(Pd-NPs),其结构经TEM, FT-IR, XRD, XPS, EA和ICP OES表征。常温常压下,以H2作氢源,水为溶剂,研究了Pd-NPs对芳香醛选择性还原反应的影响,产物结构经1H NMR和13C NMR确证。以苯甲醛的还原反应作为模板反应,研究了配体、催化剂用量和反应时间对苯甲醇产率的影响。结果表明:在最佳反应条件(配体为邻苯二胺,Pd-NPs用量10 mol%,反应5 h)下,苯甲醇产率达99%。  相似文献   

5.
以苯甲酰肼和4-醛基吡啶为原料,经过缩合反应制备亚胺型化合物1,分别与苄氯和对二苄氯结合制备了两个新型的离子液体型亚胺配体2和3,配体2和3分别与醋酸钯反应得到新型离子液体型钯配合物4和离子液体型自组装钯配合物5,其结构经1H NMR,13C NMR,IR和MS确证。   相似文献   

6.
以3-卤氧化吲哚、哌啶或吡咯烷为起始原料,碳酸钠为催化剂,于65 ℃经3-叔胺基化反应,合成了15个新型的3-哌啶/吡咯烷氧化吲哚,收率84%~93%,其结构经1H NMR, 13C NMR和HR-MS(ESI-TOF)表征。  相似文献   

7.
以醇溶性曙红为催化剂,在温和条件下高效催化缩醛化反应,该催化体系适应于不同种类的脂肪醛或芳香醛与短链一元醇或二元醇的羰醇缩合反应,于室温反应24 h,缩醛化产物收率58%~99%,其结构经1H NMR, 13C NMR和HR-MS确证。  相似文献   

8.
万顺莉  王淳  杨海君  梅青刚 《合成化学》2021,29(10):872-877
以邻羟基二芳基乙烯为底物,十二烷基硫醇为催化剂,在氧气氛围、无溶剂条件下构建了一种合成2-芳基苯并呋喃类化合物的新方法,产率28%~91%,其结构经1 H NMR, 13 C NMR, HR-MS(ESI)和LR-MS(APCI)确证。   相似文献   

9.
FeCl3为催化剂,在甲苯/水双相溶剂体系中,以稻草为原料经水解反应制备糠醛,其结构经1H NMR和13C NMR确证。通过响应面分析获得的最佳反应条件为:催化剂质量分数23.09%,甲苯60 mL,溶剂比V(甲苯): V(水)=1 : 1,料液比为67.5 g·L-1,于177 ℃反应60 min,糠醛收率高达78.92%。  相似文献   

10.
以二茂铁为原料,乙酸酐、丙酸酐、丁酸酐和苯甲酸酐为酰化剂,45%~47%三氟化硼乙醚溶液为催化剂,无溶剂合成了4种酰基二茂铁,总产率81%~92%,其结构经1H NMR和13C NMR确证。  相似文献   

11.
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   

12.
13.
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   

14.
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   

15.
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   

16.
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   

17.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

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18.
实验教学目的是从解决实际问题出发,以实验技术训练和实验设计思想培养为目标。介绍了将单一的物质分配系数测定实验改进为综合实验,提高了实验效果及实验资源利用率。  相似文献   

19.
Sets of hydrogen molecule equivalents have been developed which permit the calculation of hydrogenation of different types of carbon-carbon bonds from ab initio total energies (3-21G and 6-31G* basis sets, and, to a more limited extent, for MP2/6-31G* data) of reactants and products. The calculated enthalpies of hydrogenation are in good agreement with experiment for unstrained molecules, with average errors on the order of 2 kcal/mol. The 6-31G* equivalents allow the enthalpies for strained molecules to be calculated accurately, but the 3-21G equivalents do not. The equivalents for both basis sets have been tested by calculating the enthalpies of hydrogenation of carbon-carbon bonds in nitrogen- and oxygen-containing organic molecules, free radicals, and classical carbocations. The results are in good agreement with experiment in most cases.  相似文献   

20.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

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