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1.
新型除草剂威霜合成方法的改进   总被引:1,自引:0,他引:1  
汪进  薛玉 《合成化学》1998,6(3):328-331
以对硝基氯苯为原料,经四步合成制各间体2,6-二氯苯并恶唑,以对苯二酚和2-氯丙酸为原料,经一步合成了另一中间体2-(4-羟基苯氧基)丙酸乙酯,两个中间体在二甲亚砜溶剂中,碳酸钠存在下缩合得标题化合物,全程收率为43%。  相似文献   

2.
除草剂中间体R-(+)-2-(4-羟基苯氧基)丙酸酯的不对称合成   总被引:4,自引:0,他引:4  
郝素娥  金婵  黄宪礼  祝军 《化学通报》2002,65(5):346-348
报道了一种合成苯氧丙酸类除草剂重要中间体R-(+)-2-(4-羟基苯氧基)丙酸乙酯(即R-(+)-HPE)的方法,以L-乳酸为起始原料,先经酯化合成L-乳酸乙酯,再与对甲苯磺酰氯反应制备L-对甲苯磺酰乳酸乙酯,再与对苯二酚综合获得R-(+)-2-HPE,产品的总收率为72.1%。通过元素分析和红外光谱测定,确定了所合成的R-(+)-HPE的化学结构和纯度;由旋光度的测定,确定了所合成的R-(+)-HPE的光学纯度为95.7%。  相似文献   

3.
合成5-氯2-氨基苯膦酸的新方法   总被引:1,自引:0,他引:1  
报道了以2.5-二氯苯胺为原料合成5-氯-2氨基苯膦酸的新方法,总产率达41%,是文献报道的以间氯苯胺为原料的合成方法的总产率的近3倍。  相似文献   

4.
以环戊酮、正戊醛为原料,采用相转移催化技术进行羟醛缩合,经脱水得到2-戊叉环戊酮,再经异构化,合成了2-戊基环戊-2-烯酮。文章对相转移催化合成2-戊叉环戊酮及其异构化的条件进行了研究。  相似文献   

5.
以碘化-N-甲基-2-氯吡啶盐为缩合剂,在三乙胺存在下由3-(2-环戊酮基)丙酸及3-(2-环己酮基)丙酸分别同四氢噻唑-2-硫酮反应,得到新化合物N-(2-环戊酮基内酰基)四氢噻唑-2-硫酮(2a)及N-(2-环己酮基丙酰基)四氢噻唑-2-硫酮(2b),产率分别为52.9%和51.0%,2a,b分别同甲醇、乙醇反应得到相应的3-(2-环戊酮基)丙酸酯3a,b及3-(2-环己酮基)丙酸酯3c,d,3a~d的产率为75~87%;2a、b分别同胺反应得到3-(2-环戊酮基)内酰胺4a、b及3-(2-环己酮基)内酰胺4c、d,4a~d产率为78~93%。  相似文献   

6.
首次报道了以D-葡萄糖为原料合成新型光学活性葡萄糖衍生类β-氨基醇化合物的新方法。目标化合物:(2S,3S)-甲基-2-脱氧-2-苯胺基-4,6-o-苄叉基-α-D-吡喃阿卓糖苷(7)经各种分析测试手段证实。  相似文献   

7.
以丙烯酰胺(AM),丙烯酸甲酯(MA)和2-丙烯酰胺基-2-甲基丙磺酸(AMPS)为原料,通过水溶液共聚,合成了一种新的三元共聚物。研究了影响共聚反应的因素,并对其结构进行了表征。  相似文献   

8.
以α-(1,2,4-三唑-1-基)-α-苯甲酰基烯酮二甲硫缩醛为反应中间体,与取代苯胺、邻苯二胺、乙二胺、乙醇胺和巯基乙醇反应,合成了27个标题化合物。初步的生物活性测定结果表明:所合成的部分化合物具有抑菌及植物生长调节活性。  相似文献   

9.
本文以2-氰基-4-硝基-6-溴苯胺为原料,经重氮化后与邻异丙基苯酚偶联,合成2-(2-氰基-4-硝基-6-溴苯偶氮)-6-异丙基苯酚,用乙醇重结晶精制。用元素分析,波谱等鉴定其结构,并测定其离解常数,研究该试剂的一般性质。发现其与Cu2+、Ni2+、Co2+等的显色反应在吐温80表面活性剂存在下有较高的灵敏度。  相似文献   

10.
以(+)-4,10-二氧杂三环[5.2.1.O^2,6]-癸-8-烯-3-醇为原料。经8步反应,对映选择性地合成出去氧维生素H的重要中间体:(2S,3S,4R)-2-正戊基-3,4-二叠氮基四氢噻吩。为对映选择性合成手性四氢噻吩类化合物提供了新的方法。  相似文献   

11.
Abstract

A Horner-Wadsworth-Emmons reagent-ethyl 2-(diethylphosphono)propionate in the reaction with 2,2-disubstituted-1,3-cyclopentanediones, results in 4-oxohexanoic acid ethyl ester derivative up to 90% isolated yield. 31P-13C- and 1H-NMR study of the intermediates of the reaction involving the ethyl 2-(diethylphosphono)propionate was accomplished.  相似文献   

12.
In this project, 2‐[N‐ethyl‐N‐[4‐[(4′‐nitrophenyl)azo]‐phenyl]amino]ethanol (Disperse Red‐I) was prepared by adding of (N‐ethyl‐2‐anilinoethanol) with the salt diazonium p‐nitroaniline. The main mesogenic liquid crystalline (LC) 2‐[N‐ethyl‐N‐[4‐[4′‐nitrophenyl)azo]‐phenyl]amino]ethyl‐3‐chloro propionate (Disperse Red‐II) was synthesized by reaction of disperse Red I and 3‐chloropropanoeic acid at the alkaline condition. Then 2‐anilinoethyl‐3‐chloropropionate‐{2‐[ethyl[4‐[(4′‐nitrophenyl)azo]phenyl]amino] ethanol}, (2AECP‐Red‐I) was prepared via reaction of disperse red‐II and 2‐anilinoethanol. On the other hand, poly 2‐anilinoethyl‐3‐chloropropionate‐{2‐[ethyl[4‐[(4′‐nitrophenyl)azo]phenyl]amino]ethanol} and poly(2AECP‐Red‐I) have been synthesized by polymerization of 2AECP‐Red‐I in two separate schemes. These include polymerization in the absence of electric field (EF) and polymerization under different EFs. A comparison of the results reveals that the polymer produced under electric field is more linear, regular in shape with high electrical conductivity, as well as good LC behavior with semectic texture. The resulted monomer and poly(2AECP‐Red‐I) are characterized by using Fourier transform infrared and ultraviolet–visible and were studied by thermogravimetric analysis and differential scanning calorimetry. Scanning electron microscopy images supported the formation of poly(2AECP‐Red‐I) and showed morphology feature and homogeneous structure on poly(2AECP‐Red‐I). Electrical conductivity of poly(2AECP‐Red‐I) has been studied by four‐point probe method. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

13.
以1-苯基-2-氯-1-酮为原料,经缩酮保护、重排、水解、酯化及氯甲基化等反应制得关键中间体2-(4-氯甲基苯基)丙酸甲酯(7); 7与2-乙氧羰基环戊酮缩合后,再经脱羧及成盐反应合成了洛索洛芬钠,总收率36%,其结构经1H NMR和MS(ESI)确证。  相似文献   

14.
在(R)TTCA·K催化下由环己酮直接与丙烯酸甲酯进行Michael加成反应得到了(S)-3-(2′-氧环己基)-丙酸甲酯, [α]20D-4.14(41.5% e.e.).  相似文献   

15.
Characteristic aroma volatile compounds from different parts of cayenne pineapple were analyzed by headspace-solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC/MS). The main volatile compounds were esters, terpenes, ketones and aldehydes. The number and content of aroma compounds detected in pulp were higher than those found in core. In pulp, the characteristic aroma compounds were ethyl 2-methylbutanoate, ethyl hexanoate, 2,5-dimethyl-4-hydroxy-3(2H)-furanone (DMHF), decanal, ethyl 3-(methylthio)propionate, ethyl butanoate, and ethyl (E)-3-hexenoate; while in core the main compounds were ethyl 2-methylbutanoate, ethyl hexanoate and DMHF. The highest odor units were found to correspond to ethyl 2-methylbutanoate, followed by ethyl hexanoate and DMHF. The odor units found for pulp were higher than those for core.  相似文献   

16.
合成了三-(4-甲基苯甲酸)纤维素酯(MCTB)手性固定相,用反相高效液相色谱法在该手性固定相上对2-(4-羟基苯氧基)丙酸酯对映体进行拆分.实验结果表明,在三-(4-甲基苯甲酸)纤维素酯手性固定相上,以甲醇与水的体积分数为75:25做流动相能较好的拆分2-(4-羟基苯氧基)丙酸甲酯、乙酯和丁酯对映体,其分离因子分别为1.38、1.49、0.98;同时还发现2-(4-羟基苯氧基)丙酸酯中酯基团的大小对其对映体的分离也有明显的影响,其中以乙酯的拆分效果最佳。  相似文献   

17.
采用二乙二醇和丙酸甲酯为主要原料,以钾为催化剂,在通N_2气保护的条件下合成二乙二醇丙酸甲酯,用离子排阻高效液相色谱法对合成的二乙二醇丙酸甲酯进行定量分析。最佳合成条件:二乙二醇与丙酸甲酯的物质的量比为1∶2,催化剂的质量为反应物二乙二醇质量的1.5%,于25℃条件下反应24 h,产物经硅胶柱分离、乙酸乙酯梯度洗脱,然后干燥,制得二乙二醇丙酸甲酯成品,收率为61.5%,纯度达99.5%。用FT-IR,~1H–NMR,GC–MS法对二乙二醇丙酸甲酯的分子结构进行了确证。  相似文献   

18.
By an example of butanethiol the addition of mercaptanes in the presence of bases to alkyl 3-furyl-3-(diethoxyphosphoryl)acrylic acids having methyl, methoxymethyl, or diethoxyphosphorylmethyl substituent in the furan ring was studied. It was shown that in the majority of cases alkyl 2-(butylthio)propionate was the main product, and 3-(butylthio)propionate was the minor one. Ethyl 3-(4-methylfur-3-yl)-3-(diethoxyphosphoryl) acrylate affords these two substances in equal quantities. In the case of ethyl 3-(4-methoxymethyl-5-methylfur-2-yl)-3-(diethoxyphosphoryl)acrylate only 3-(butylthio)propionate is formed.  相似文献   

19.
Ethyl propionate is a model for fatty acid ethyl esters used as first-generation biodiesel. The atmospheric chemistry of ethyl propionate was investigated at 980 mbar total pressure. Relative rate measurements in 980 mbar N(2) at 293 ± 0.5 K were used to determine rate constants of k(C(2)H(5)C(O)OC(2)H(5) + Cl) = (3.11 ± 0.35) × 10(-11), k(CH(3)CHClC(O)OC(2)H(5) + Cl) = (7.43 ± 0.83) × 10(-12), and k(C(2)H(5)C(O)OC(2)H(5) + OH) = (2.14 ± 0.21) × 10(-12) cm(3) molecule(-1) s(-1). At 273-313 K, a negative Arrhenius activation energy of -3 kJ mol(-1) is observed.. The chlorine atom-initiated oxidation of ethyl propionate in 980 mbar N(2) gave the following products (stoichiometric yields): ClCH(2)CH(2)C(O)OC(2)H(5) (0.204 ± 0.031), CH(3)CHClC(O)OC(2)H(5) (0.251 ± 0.040), and C(2)H(5)C(O)OCHClCH(3) (0.481 ± 0.088). The chlorine atom-initiated oxidation of ethyl propionate in 980 mbar of N(2)/O(2) (with and without NO(x)) gave the following products: ethyl pyruvate (CH(3)C(O)C(O)OC(2)H(5)), propionic acid (C(2)H(5)C(O)OH), formaldehyde (HCHO), and, in the presence of NO(x), PAN (CH(3)C(O)OONO(2)). The lack of acetaldehyde as a product suggests that the CH(3)CH(O)C(O)OC(2)H(5) radical favors isomerization over decomposition. From the observed product yields, we conclude that H-abstraction by chlorine atoms from ethyl propionate occurs 20.4 ± 3.1%, 25.1 ± 4.0%, and 48.1 ± 8.8% from the CH(3)-, -CH(2)-, and -OCH(2)- groups, respectively. The rate constant and branching ratios for the reaction between ethyl propionate and the OH radical were investigated theoretically using quantum mechanical calculations and transition state theory. The stationary points along the reaction path were optimized using the CCSD(T)-F12/VDZ-F12//BH&HLYP/aug-cc-pVTZ level of theory; this model showed that OH radicals abstract hydrogen atoms primarily from the -OCH(2)- group (80%).  相似文献   

20.
乙醇直接气相羰基化新催化剂   总被引:1,自引:0,他引:1  
醇的羰基化合成是极有工业价值的过程 ,也是绿色化学中提倡的原子经济性反应 [1] .甲醇均相羰基化合成醋酸是 Monsanto公司成功开发应用的典范 [2 ] ,而乙醇羰基化合成丙酸或丙酸乙酯的研究尤其重要 .前文对一种性能优良的负载型 Ni系催化剂用于乙醇常压气相羰基化合成丙酸及其酯作了报道 [3,4] ,与均相羰基化相比 ,该反应具有条件温和 ,不使用贵金属铑 ,催化剂与产物不存在分离上的困难等优点 ,但反应体系仍需使用卤化物作促进剂 .由于碘乙烷的存在 ,反应系统设备腐蚀严重 (有 HI生成 ) ,产物分离精制复杂 .目前 ,醇的均相羰基化及多相羰…  相似文献   

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