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1.
以草酸二乙酯为原料,经酰胺化、环合、成盐及硝化反应合成了5-氯-1-甲基-4-硝基咪唑,总收率61.3%,其结构经1H NMR, IR和MS表征.本方法有两点改进: (1)在酰胺化反应中用30%~40%甲胺水溶液代替甲胺气体; (2)在成盐反应中直接向环化产物的丙酮溶液加硝酸析出5-氯-1-甲基咪唑硝酸盐晶体.  相似文献   

2.
以2-胺基-5-碘苯甲酸为起始原料,经四步反应合成了新型喹唑啉类抗肿瘤药物拉帕替尼的关键中间体-N-{3-氯4-[(3-氟苄基)氧基]苯基}-6-碘喹唑啉-4-胺,总收率77.9%,其结构经1H NMR和ESI-MS确证.Williamson醚化反应的最佳条件为:4-(6-碘喹唑啉-4-基氨基)-2-氯苯酚(5)30.0 mmol,K2CO3 24.8 g,18-冠-6 0.79 g,KI 0.49 g,丙酮250 mL.于35℃反应12 h,收率90.1%.  相似文献   

3.
通过酰氯制备异硫氰酸酯,与5-(4-氨基苄基)-2,4-咪唑啉二酮反应合成了含2,4-咪唑啉二酮的N-苯甲酰基-N'-苯基硫脲,然后在三乙胺存在下再与溴丙酮发生碱催化缩合反应以中等以上收率合成了新型含2,4-咪唑啉二酮的4-甲基-3-苯基-2-酰亚胺噻唑啉,它们的化学结构经1H NMR,IR,HR-ESI-MS和化合物3g和4g的X-ray单晶衍射表征,硫脲与溴丙酮的反应机理通过化合物3g和4g的晶体结构得到进一步确证.初步生物活性测定结果表明:部分目标化合物对供试昆虫及菌种显现出良好的抑制活性,如在200 mg/L浓度下化合物3i和4q对小菜蛾的死亡率分别为86%和100%,在50 mg/L浓度下化合物4n对油菜菌核菌的抑制率为82.6%,而它们对油菜和稗草显示出微弱但并不特征的除草活性.  相似文献   

4.
1-(4-乙酰氨基苯基)-α-溴代-1-丙酮(I)是合成强心药物匹莫苯(Pirnobendan)和新型抗抑郁类药物氨基酮的主要中间体,它可以1-(4-乙酰氨基苯基)丙酮(Ⅱ)为原料,通过α位溴代得到。主要方法有:(1)以冰醋酸作溶剂,滴加溴的醋酸溶液反应后,经氯仿萃取,硅胶G柱层析分离得产品。  相似文献   

5.
高纯度3,4-二羟基苯甲醛的制备   总被引:4,自引:1,他引:3  
夏春年  陈利民  胡惟孝 《合成化学》2004,12(5):484-486,494
研究了香兰素经脱甲基制备3,4-二羟基苯甲醛的反应。正交试验确定最佳反应条件为:香兰素7.8g(51 mmo),CH2Cl2 15mL(234mmo1),无水AlCl3 9.4g(70mmo1),吡啶13.3g(168mmol)和TEBA 0.05g,反应温度48℃,回流时问28h,收率92.6%,纯度99.7%(HPLC)。  相似文献   

6.
在水溶剂中有三乙基苄基氯化铵(TEBA)存在下,α,β-不饱和酮与3-甲基- 1-苯基-2-吡唑啉-5-酮发生迈克尔加成反应,以良好的产率生成相应的1,3-二芳基 -3-(3'-甲基-1'-苯基-5'-羟基-2'-吡唑啉-4'-基)-1-丙酮。  相似文献   

7.
在K2CO3-TEBA-DNIF体系中,2-(2-氧-4-硝基苯磺酰基)-1-芳基乙酮与各种烷基化试剂发生烷基化-环化反应,得到一系列3-位取代的1,4-氧硫杂萘4,4-二氧化物,并讨论了反应机理和反应条件.  相似文献   

8.
顶空毛细管气相色谱法测定茶多酚中有机溶剂的残留量   总被引:2,自引:0,他引:2  
建立了顶空毛细管气相色谱法测定茶多酚中正己烷、氯仿、乙酸乙酯和丙酮4种有机溶剂残留量的方法.并讨论了平衡温度、平衡时间、盐效应对测定的影响.分析结果表明:该方法对上述4种有机溶剂均达到了完全分离,相关系数为0.994~0.999,检出限范围为0.065~0.268 μg/g,测定结果的相对标准偏差为0.39%~2.13%,样品的回收率为90.9%~105.3%.  相似文献   

9.
水介质中在氯化三乙基苄基铵(TEBA)催化下, 芳醛与丙二腈和4-羟基香豆素三组分一锅反应合成了2-氨基-4-芳基-3-氰基-1,6-二氧-5-氧代-1,4,5,6-四氢化菲, 该反应具有产率高、污染少、操作简单、环境友好等优点.  相似文献   

10.
毛细管气相色谱法测定5种中草药中有机氯农药的残留量   总被引:38,自引:0,他引:38  
建立了怀牛夕等 5种中草药中六六六及滴滴涕异构体含量的气相色谱分析方法。样品以石油醚 +丙酮在索氏提取器中提取 ,提取液以浓硫酸净化。采用SE 30弹性石英毛细管柱分离样品 ,GC ECD检测六六六、滴滴涕农药的残留量。方法的线性范围为 5 .7× 10 - 7~ 2 .8× 10 - 4μg ;最小检测量为 1.3× 10 - 1 4~ 2 .5×10 - 1 2 g ;加样平均回收率为 88.8%~ 99.1% ;RSD为 0 .9%~ 5 .3%。  相似文献   

11.
The reaction of arylazomethoxycarbonylmethylenetriphenylphosphoranes 1 with chloroform and sodium hydroxide in the presence of benzyltriethylammonium chloride (TEBA) as phase transfer catalyst directly affords 5-chloro-3-methoxycarbonyl-1-arylpyrazoles 3 .  相似文献   

12.
Ring opening of 1,1-dibromo-2-chloro-2-diethoxymethylcyclopropane in a mixture of ethanol and dichloromethane with 50% aqueous sodium hydroxide in the presence of triethylbenzylammonium chloride (TEBA) gave 3,3,4,4-tetraethoxybut-1-yne (TEB) in excellent yield. This alkyne appears to be thermally stable at least up to 150 °C. The compound is also stable in neutral and basic aqueous solutions. In acidic aqueous media, however, TEB is unstable and was converted to one or several products depending on the reaction conditions. The most useful reaction appears to be deketalization to give 1,1-diethoxybut-3-yn-2-one, which was obtained in quantitative yield under the optimum conditions.  相似文献   

13.
郑敏燕  魏永生  安忠维 《有机化学》2008,28(11):1948-1953
提出了一种在无水丙酮体系中, 采用KMnO4选择性氧化芳环上醛基的新方法. 运用此法, 氧化烷基多环苯酰氧基苯甲醛制备相应的苯甲酸. 采用循环伏安法研究了KMnO4在丙酮体系中的氧化活性, 利用红外光谱探讨了氧化反应的机理, 产物结构用IR, MS, 1H NMR及元素分析表征. 结果表明, 在无水丙酮体系中, KMnO4的氧化活性明显降低, 可以在芳环上同时存在烷基和醛基时, 选择性氧化醛基, 选择性达100%. 经正交试验确定反应最佳条件为高锰酸钾用量为原料的2倍, 反应时间4 h, 酸解时间1.5 h, 产率94%. 通过对结构类似化合物的合成, 表明该法具有一定的普遍性.  相似文献   

14.
Recently we have described a new catalytic method of generation of dichlorocarbene and simple synthesis of dichlorocyclo-propane derivatives in two-phase system1. This method consists in reaction of chloroform and olefin with concentrated aqueous NaOH solution in the presence of quaternary ammonium compounds that acts as a catalyst. In our hands triethylbenzylammonium chloride TEBA was the most convenient catalyst.  相似文献   

15.
Blends of high cyanoethylated cellulose (HCEC) (Ds = 2.5) and cellulose triacetate (CTA) (Ds = 2.8) were prepared for evaluation as ultrafiltration membranes. The rejection Ra and water permeability (Pw) of these membranes with respect to bovine serum albumin (BSA), were measured with the variations in composition and conditions of preparation. It was possible to define the reaction conditions and compositions that offered optimum performance with respect to Ra and Jw, and resistance to microbial degradation as well as acid and alkali hydrolysis. The morphology of membrane thereby obtained was characterized by scanning electron microscopy (SEM). The UF membrane cast from a solution of 1,4-dioxane: 12.5 g, acetone: 12.5 g, HCEC: 1.5 g, CTA: 3 g and PEG (MW = 1000): 10.5 g showed the optimum performance of Pw = 10 × 10−10 m3/(m2 s Pa), BSA Rejection (Ra) = 99%, (Jw = 17.3 m3/(m2 day) at ΔP = 0.2 MPa) and a molecular weight cut off at 4.9 × 104 Da. After immersion in mud for 170 days, reduction of Ra was only 8% for UF membrane containing 10 wt% HCEC blend, and was not observed to be obviously different from the membrane containing more than 30 wt% HCEC blend. The higher permeability and rejection of blend membrane may be attributable to the network structure formed via CTA and HCEC penetration.  相似文献   

16.
以芳亚甲基丙二腈或2-氰基-3-芳基丙烯酸酯和4-羟基喹啉-2-酮为原料, 水为溶剂, 在TEBA(三乙基苄基氯化铵)催化下90 ℃, 合成了2-氨基-4-芳基-5,6-二氢化-4H-吡喃[3,2-c]喹啉-5-酮衍生物. 和其它方法相比, 该反应具有反应条件温和, 产率高(87%~96%)和环境友好等优点. 产物的结构通过熔点, IR, 1H NMR和元素分析表征. 化合物3m的结构通过X单晶衍射分析确证.  相似文献   

17.
Hydrogen bonds formed between C-H and various hydrogen bond acceptors play important roles in the structure of proteins and organic crystals, and the mechanisms of C-H bond cleavage reactions. Chloroform, a C-H hydrogen bond donor, can form weak hydrogen-bonded complexes with acetone and with dimethylsulfoxide (DMSO). When chloroform is dissolved in a mixed solvent consisting of acetone and DMSO, both types of hydrogen-bonded complexes exist. The two complexes, chloroform-acetone and chloroform-DMSO, are in equilibrium, and they rapidly interconvert by chloroform exchanging hydrogen bond acceptors. This fast hydrogen bond acceptor substitution reaction is probed using ultrafast two-dimensional infrared (2D-IR) vibrational echo chemical exchange spectroscopy. Deuterated chloroform is used in the experiments, and the 2D-IR spectrum of the C-D stretching mode is measured. The chemical exchange of the chloroform hydrogen bonding partners is tracked by observing the time-dependent growth of off-diagonal peaks in the 2D-IR spectra. The measured substitution rate is 1/30 ps for an acetone molecule to replace a DMSO molecule in a chloroform-DMSO complex and 1/45 ps for a DMSO molecule to replace an acetone molecule in a chloroform-acetone complex. Free chloroform exists in the mixed solvent, and it acts as a reactive intermediate in the substitution reaction, analogous to a SN1 type reaction. From the measured rates and the equilibrium concentrations of acetone and DMSO, the dissociation rates for the chloroform-DMSO and chloroform-acetone complexes are found to be 1/24 ps and 1/5.5 ps, respectively. The difference between the measured rate for the complete substitution reaction and the rate for complex dissociation corresponds to the diffusion limited rate. The estimated diffusion limited rate agrees well with the result from a Smoluchowski treatment of diffusive reactions.  相似文献   

18.
以布洛芬(IPF)和扑热息痛(PCM)为原料,无水丙酮和乙酸乙酯为溶剂,二环己基碳二亚胺(DCC)为脱水剂,4-二甲氨基吡啶(DMAP)为催化剂,合成了布洛芬-扑热息痛孪药(PHI),以重结晶法对目标产物进行纯化,产物结构经IR和1H NMR确定。 探讨了原料比例、脱水剂用量、催化剂用量、反应时间和溶媒用量对目标物产率的影响,并采用正交试验筛选最优合成工艺,最终确定的最优反应条件为:n(PCM)∶n(IPF)=1∶1.5,催化剂的最佳用量为布洛芬质量的10%,反应时间为8 h,溶媒体积为70 mL(V(乙酸乙酯)∶V(丙酮)=1∶1),在该条件下,目标物PHI的产率为66.53%。  相似文献   

19.
采用碾磨-活化法制备了SiO2-ZnCl2(Silzic)催化剂,并将其用于异丁烯与甲醛Prins缩合合成3-甲基-3-丁烯-1-醇(MBOH)。系统研究了温度、物料比、时间和催化剂的组成及用量对该反应的影响。结果表明,在不同的条件下,甲醛都保持着99%以上的高转化率;然而,不同的条件对MBOH的选择性和收率的影响程度不同,其中,反应温度、催化剂的酸量是影响该反应的关键因素;物料比和反应时间对MBOH的选择性和收率的影响相对较小。实验得到最佳的反应条件为,反应温度210 ℃、二氧六环8 g、三聚甲醛1.5 g、n(异丁烯)/n(三聚甲醛)=7:1、30 mg 1 mmol/g Silzic 和反应时间2 h,在此条件下MBOH的选择性和收率可分别达到93.8%和93.4%。当催化剂循环使用五次时,MBOH的收率降为85.2%,表明该催化剂具有一定的重复使用性。  相似文献   

20.
硫酸氢钠催化合成环己烯   总被引:10,自引:0,他引:10  
李继忠 《合成化学》2004,12(3):311-312
以硫酯氢钠为催化剂,对环己醇脱水制备环己烯的反应进行研究。通过考察影响反应的因素得出最佳反应条件为:环己醇15g(150mmol),催化剂用量为环己醇质量的7%,反应时间1h,收率达89.4%。  相似文献   

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