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1.
亚甲基异吲哚酮衍生物2是一类重要的药物合成中间体,近来又被用作新型有机金属染料合成的配体。文献报道化合物2的主要合成方法是采用苯基锂衍生物的分子内反应,或以有机钛为主要原料合成目标产物,但以上方法原料难得,反应条件苛刻,产率不理想,难以大规模合成。我们首次发现以苯基环缩醛为原料一步法合成亚甲基异吲哚酮2的新方法,原料易得,条件温和,操作简便,产率良好,为本甲醛作起始原料合成化合物2提供了一条新途径。  相似文献   

2.
报道了3-亚甲基异苯并呋喃-1(3H)-酮及其衍生物简易、高效的合成方法.其特点是原料易得且价格低廉、反应条件温和、收率高.该方法以2-甲基苯甲酸及其衍生物为原料,经过酯化、自由基溴代和三苯基膦发生亲核取代反应合成了2-[(溴三苯基正膦基)甲基]苯甲酸甲酯及其衍生物;随后发生Wittig反应、羧酸酯碱性条件下水解得到2-乙烯基苯甲酸及其衍生物;接着和碘(NBS)发生环合反应,生成3-碘(溴)甲基异苯并呋喃-1(3H)-酮及其衍生物;最后消除卤化氢得到目标化合物.  相似文献   

3.
黄宪  吴国永 《有机化学》1989,9(5):460-462
2H-吡喃-2-酮及其衍生物是有机合成的蓬要中间体。对于它们的合成已有许多报道,例如利用烯醇醚或烯醇砖醚与丁酰氯反应;羰基化合物与甲氧亚甲螭丙二酸二甲酯反应;α-苯基丙醛酸酯与丙酮的成环缩合2,6-二氯-3-三氯甲基吡啶与亚甲基丁二酸酯的反应,邻氰基苯乙炔、二苯乙二酮和丙酮的反应。但上述方法往往原料较难得到,产率较低或操作麻烦。  相似文献   

4.
2-硫代-4-咪唑啉二酮的合成与表征   总被引:1,自引:1,他引:0  
孙勇  丁明武 《化学研究与应用》2004,16(5):675-676,679
咪唑啉酮衍生物是一类线粒体呼吸抑制剂,对果树黑斑病及由卵菌引起的霜霉病、疫病等的活性很好。2-硫代-5-苯基亚甲基4-咪唑啉二酮衍生物不能用通法制取,其起始原料烯基氨基酸不稳定。本文用三组分串联aza-Wittig堍反应合成2-硫代-3-烷基-5-苯基亚甲基4-咪唑啉二酮类化合物。合成路线如下:  相似文献   

5.
孙勇  丁明武 《合成化学》2003,11(6):469-471,498
用2-硫代-3-正丁基-5-苯基亚甲基4-咪唑啉二酮的-S-烷基化反应合成了2-烷硫基-3-正丁基-5-苯基亚甲基-4H-咪唑啉-4-酮衍生物。探讨了S-烷基化反应的反应条件和所合成化合物的波谱性质。目标产物均为新的化合物,其结构经元素分析,IR,1H NMR和MS确正。  相似文献   

6.
张继振  吴健  王雅珍  赵德建  贾洪斌 《有机化学》2012,32(12):2344-2349
以2-乙烯基苯甲酸甲酯及其衍生物为原料,经过酯水解反应,随后发生环氧化、环合反应制备了3-羟甲基异苯并呋喃-1(3H)-酮及其衍生物;再和三溴化磷或者对甲苯磺酰氯发生亲核取代,最后通过消除反应合成了3-亚甲基异苯并呋喃-1(3H)-酮及其衍生物.在亲核取代和消除反应中,对甲苯磺酰氯法比三溴化磷法产率高.目标产物及其中间体有10个是新化合物.化合物结构用1H NMR,13C NMR,MS和IR表征.目标产物在空气中长期放置没有发生二聚.  相似文献   

7.
以碱性离子液体1-(2-氨基乙基)-3-甲基咪唑咪唑盐([2-aemim]im)作为催化剂,催化Knoevenagel反应和4-芳亚甲基异噁唑-5(4H)-酮衍生物的合成。实验结果表明:在无溶剂条件下,该离子液体对Knoevenagel反应具有很高的催化活性,一系列芳香醛和活泼亚甲基化合物的反应在室温条件下2 min内顺利完成,均以90%以上的高产率生成取代烯烃产物.将该碱性离子液体用于催化乙酰乙酸乙酯或苯甲酰乙酸乙酯、盐酸羟胺和芳香醛三组分一锅法缩合制备4-芳亚甲基异噁唑-5(4H)-酮衍生物,具有反应时间较短、产率较高和后处理简单的特点。离子液体经简单处理后能多次循环使用。  相似文献   

8.
邻亚甲基苯醌化合物是一类非常活泼和重要的中间体,被广泛应用于天然产物和药物化学中.以2-[羟基(苯基)甲基]苯酚类化合物和胺为原料,1,2-二氯乙烷为溶剂,在Sc(III)促进下原位生成邻亚甲基苯醌,并发生氮杂迈克尔加成反应合成贝蒂碱衍生物.反应在封管条件下90℃搅拌4 h完成,以76%~96%的产率得到目标产物.  相似文献   

9.
新型吡咯类衍生物的合成   总被引:4,自引:0,他引:4  
2,5-己二酮和胺(氨基硫脲、硫脲、苯胺、氨基酸)经过Paal-Knorr反应合成6个2,5-二甲基-N-取代吡咯衍生物;分别以新合成的N-吡咯甘氨酸、N-苯基吡咯化合物为原料,进行酯化反应和Mannich,Friedel-Craft反应,合成3个N-(2,5-二甲基吡咯)甘氨酸酯类化合物和2个N-苯基-2,5-二甲基吡咯衍生物.所有化合物都通过IR,1HNMR,13CNMR,HRMS波谱方法对其结构进行了确证.  相似文献   

10.
刘斌  仝红娟  朱周静  张彦民  郭惠 《化学通报》2020,83(10):946-950
以仲胺、氧杂环丁-3-酮和三甲基氰硅烷为原料,无水甲醇为溶剂,无需催化剂,一步反应合成目标化合物3-仲氨基氧杂环丁烷-3-腈衍生物(1a~1d),产物结构经1H NMR和ESI-MS表征。并以异吲哚啉、氧杂环丁-3-酮和三甲基氰硅烷的反应为模型反应,考察影响产物1a收率的主要因素,确定最佳反应条件为:物料摩尔比为n(异吲哚啉): n(氧杂环丁-3-酮): n(三甲基氰硅烷)= 2.0 : 1 : 2.5;反应溶剂为无水甲醇,在65 ℃反应6 h。在最佳反应条件下,化合物1a收率78.3 %。对于目标化合物的应用进行了研究,发现化合物1a与苯基溴化镁在四氢呋喃溶剂中,室温反应5 h,得到2-(3-苯基氧杂环丁烷-3-基)异吲哚啉(4)和 [3-(异吲哚啉-2-基) 氧杂环丁烷-3-基](苯基)甲酮(5),收率分别为40.1 %和31.5 %。  相似文献   

11.
A metal-free route involving a sequential reaction of 2-alknylbenzoate and aryl-1,2-diamine is described for the generation of 2-(quinoxalin-2-yl)benzoate. The sequential reaction combines NBS-mediated diketonization of 2-alknylbenzoate and condensation reaction with aryl-1,2-diamine, and proceeds smoothly under mild reaction conditions and an array of 2-(quinoxalin-2-yl)benzoate is achieved with high efficiency and excellent functional group tolerance. Mechanism studies indicate oxygen transfer reaction is observed and water is incorporated into neighboring ester group.  相似文献   

12.
The reaction between aquacobalamin, Cbl(H2O), and NO was studied at low pH. As previously reported, the final product of the reaction is the same as that obtained in the reaction of NO and reduced Cbl(H2O), viz. Cbl(NO-). Nevertheless, this reductive nitrosylation is preceded by a faster reaction (accompanied by small absorbance changes) that depends on the HNO2 concentration but not on the NO concentration. Kinetic and UV-vis spectroscopic data show that Cbl(NO2-) is generated during this reaction. Spectroscopic data show that the dimethylbenzimidazole group trans to the NO2- ligand is protonated and partially dechelated at pH 1, by which a reaction with NO is induced. DFT calculations were performed to compare the ability of NO and NO2- to bind to cobalamin and their influence on the stability of the dimethylbenzimidazole group. The reductive nitrosylation reaction shows a quadratic dependence on the HNO2 concentration and an inverse dependence on the NO concentration. It also strongly depends on pH and is no longer observed at pH > 4. On the basis of earlier work performed on a series of Co(III) porphyrins, a mechanism is proposed that can quantitatively account for the HNO2 and NO dependencies. The reductive nitrosylation reaction is practically dominated by a back reaction, i.e., the reaction between Cbl(NO-) and HNO2, which accounts for the strange NO and HNO2 concentration dependencies observed.  相似文献   

13.
分散蓝2BLN染料的二氧化氯氧化脱色研究   总被引:2,自引:0,他引:2  
我们用CIO2氧化分散蓝2BLN,对其进行脱色,在1分钟内脱色率为90%以上。在最佳条件下,研究了反应的动力学。用PMS半经验方法计算了2BLN分子的键级。结果表明,脱色反应的级数,对2BLN为1级,对CIO2为0.5级,这个反应是十分快的,开始于一个Sn2亲核历程。  相似文献   

14.
石启英 《有机化学》2004,24(8):912-915
以有机高价碘杂环化合物1,2为底物,在Pd(PPh3)2Cl2-CuCl催化剂存在下与末端炔烃进行交叉偶联反应,实验发现该反应为--化学选择性反应,控制反应体系的物料比、温度及反应时间可以分别得到单偶联或双偶联产物,从而证实了有机高价碘杂环化合物的碘盐在进行交叉偶联反应时的反应活性比sp2的碘化物高.  相似文献   

15.
A full dimensional, nine-degree-of-freedom (9DOF), time-dependent quantum dynamics wave packet approach is presented for the study of the H2+C2H-->H+C2H2 reaction system. This is the first full dimensional quantum dynamics study for a diatom-triatom reaction system. The effects of the initial vibrational and rotational excitations of the reactants on the reactivity of this reaction are investigated. This study shows that vibrational excitations of H2 enhance the reactivity; whereas, the vibrational excitations of C2H only have a small effect on the reaction probability. In addition, the bending excitations of C2H, compared to the ground state reaction probability, hinder the reactivity. Comparison of the ground state reaction probabilities of the 9DOF and 8DOF shows the reaction probability from the full dimensional calculation is larger, with more prominent resonance features.  相似文献   

16.
High selectivity to light alkenes can be achieved from CO and CO_2hydrogenation over K-Fe-MnO/Si-2 catalyst.The alkene selectivity isinsensitive to reaction temperature for CO hydrogenation,while apparentlyincreases for CO_2 hydrogenation with raising reaction temperature.An increasein alkene selectivity is observed for both CO and CO_2 hydrogenation with GHSVrising,While a decrease with the elevation of reaction pressure for both CO/H_2and CO_2/H_2 reaction.A two-step mechanism is suggested forCO_2 hydrogenation to form hydrocarbons,by which the variations incontributions of CO and HC as products of CO_2/H_2 reaction with change ofreaction temperature,GHSV and pressure are explained.Moreover,thecatalyst is favorable for selective production of light olefins,which can alsoconcern the slightly secondary reactions of light olefins to some extent.  相似文献   

17.
负载型钾盐催化剂用于合成苯甲醚的研究   总被引:2,自引:1,他引:1  
采用固定床连续进料的反应器代替传统间歇反应釜作为评价反应器,以环境友好的碳酸二甲酯为甲基化试剂,由苯酚合成苯甲醚的反应新工艺。采用SiO2负载的钾盐类催化剂,考察了反应温度、进料空速、原料配比、活性组分负载量以及催化剂用量等对反应性能的影响。研究表明,在该负载型钾盐催化剂上苯酚的转化率均较高,且生成苯甲醚的选择性较好。尤其是在KF/SiO2催化剂上,在DMC/苯酚摩尔比为2∶1,进料空速为2 h-1,反应温度为250℃时,苯甲醚收率和选择性分别高达93.93%和98.19%。而且该负载型催化剂活性比较稳定,未发现活性组分流失,反应运行16 h催化剂未见失活。  相似文献   

18.
The bimolecular single collision reaction potential energy surface of CN radical with ketene (CH2CO) was investigated by means of B3LYP and QCISD(T) methods. The calculated results indicate that there are three possible channels in the reaction. The first is an attack reaction by the carbon atom of CN at the carbon atom of the methylene of CH2CO to form the intermediate NCCH2CO followed by a rupture reaction of the C-C bond combined with -CO group to the products CH2CN CO. The second is a direct addition reaction between CN and CH2CO to form the intermediate CH2C(O)CN followed by its isomerization into NCCH2CO via a CN-shift reaction, and subsequently, NCCH2CO dissociates into CH2CN CO through a CO-loss reaction. The last is a direct hydrogen abstraction reaction of CH2CO by CN radical. Because of the existence of a 15.44 kJ/mol reaction barrier and higher energy of reaction products, the path can be ruled out as an important channel in the reaction kinetics. The present theoretical computation results, which give an available suggestion on the reaction mechanism, are in good agreement with previous experimental studies.  相似文献   

19.
The title reaction is investigated by co-expanding a mixture of Cl2 and CH2D2 into a vacuum chamber and initiating the reaction by photolyzing Cl2 with linearly polarized 355 nm light. Excitation of the first C-H overtone of CH2D2 leads to a preference for hydrogen abstraction over deuterium abstraction by at least a factor of 20, whereas excitation of the first C-D overtone of CH2D2 reverses this preference by at least a factor of 10. Reactions with CH2D2 prepared in a local mode containing two quanta in one C-H oscillator /2000>- or in a local mode containing one quantum each in two C-H oscillators /1100> lead to products with significantly different rotational, vibrational, and angular distributions, although the vibrational energy for each mode is nearly identical. The Cl+CH2D2/2000>- reaction yields methyl radical products primarily in their ground state, whereas the Cl+CH2D2/1100> reaction yields methyl radical products that are C-H stretch excited. The HCl(v=1) rotational distribution from the Cl+CH2D2/2000>- reaction is significantly hotter than the HCl(v=1) rotational distribution from the Cl+CH2D2/1100> reaction, and the HCl(v=1) differential cross-section (DCS) of the Cl+CH2D2/2000>- reaction is more broadly side scattered than the HCl(v=1) DCS of the Cl+CH2D2/1100> reaction. The results can be explained by a simple spectator model and by noting that the /2000>- mode leads to a wider cone of acceptance for the reaction than the /1100> mode. These measurements represent the first example of mode selectivity observed in a differential cross section, and they demonstrate that vibrational excitation can be used to direct the reaction pathway of the Cl+CH2D2 reaction.  相似文献   

20.
氧化钙脱硫可逆反应过程的研究   总被引:5,自引:3,他引:2  
在热天平和固定床装置上研究了CaO脱除H2S过程中可逆反应的变化规律。实验结果表明,脱硫过程的最佳温度为Ca(OH) 2分解温度(在二氧化碳不存在情况下);水蒸气和H2是影响CaO脱硫可逆反应的两个重要因素,提高水蒸气体积分数无论热力学和动力学都有利于逆反应的进行,使得脱硫效率降低,提高H2体积分数可抑制逆反应进行,当H2的体积分数达到一定值时,由多个反应构成的逆反应变为单个反应,高温脱硫精度则由反应(CaO + H2S = CaS + H2O)决定。对通过CaS水蒸气反应实现CaS转化或再生也作了讨论。  相似文献   

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