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1.
新型光稳定剂是近年来发展迅速的热门课题,2-氯-4,6-二(2,2,6,6-四甲基-4-哌啶氧基)-1,3,5-三嗪的合成是开发新型哌嗪系、受阻胺类光稳定剂的重要步骤,对用碳酸氢纳、氰尿酰氯、哌啶醇合成目标产物的反应机理进行了推测,并考察了不同反应条件对收率的影响,确定了该合成的最佳反应条件.  相似文献   

2.
以联苯和草酰氯为原料,通过傅克酰基化反应合成联苯-4-酮酸乙酯,经碱性水解得联苯-4-酮酸,在双氧水作用下,酮酸发生氧化脱羰基反应得目标产物.对酰化条件进行了优化并详细考察了氧化剂种类、双氧水浓度、物料配比、反应温度和时间对氧化脱羰基反应的影响,确定较佳的工艺条件:10%双氧水作氧化剂,n(联苯-4-酮酸)∶n(双氧水)=1∶2,反应时间为3h,反应温度为0~5℃.在此条件下,联苯-4-甲酸的收率为81.9%(以原料联苯计),纯度为99.5% (HPLC面积归一化法).产物结构经熔点、1HNMR和13CNMR和质谱表征.  相似文献   

3.
从三氯均三嗪出发通过三步反应合成了4-(9-蒽基)-6-十六烷氧基-2-氨基-1,3,5-三嗪(AHTA),并通过红外、核磁、质谱、高分辨质谱对目标产物进行了表征.研究表明AHTA分子在基态下分子的蒽环与三嗪环不共平面,激发态下表现为ICT的荧光发射.由于分子间氢键作用的存在,AHTA在自组装膜和LB膜中均形成H-聚集体.  相似文献   

4.
潘忠稳  凌冰  姚琼 《农药》2003,42(11):21-22
研究了以磷酸三(2,4-二氯)苯酯为原料,经硝化、水解合成2,4-二氯-5-硝基苯酚的工艺,讨论了反应条件对反应的影响,获得了较好的工艺条件。在优化条件二步反应总收率为97%(以磷酸三(2,4-二氯)苯酯计)。产物经IR及元素分析表征了结构。产品是合成多种高效除草剂如“稻思达”的关键中间体。  相似文献   

5.
陈邦  苟小峰  刘源发  孙晓红 《应用化工》2012,41(2):229-231,236
采用二步反应考察了4-[2-(4,6-二甲氧基嘧啶基)]-3-硫代脲酸苯酯合成的最优反应条件,通过氢谱(1H NMR)、红外光谱(IR)、元素分析和熔点测定,对所合成的产物进行结构分析。采用离体含毒介质法,对合成产物进行杀菌毒力活性的测定。结果表明,0.1 mol氯甲酸苯酯和0.2 mol硫氰酸钾,在乙酸乙酯中50℃反应2 h,滤去生成的氯化钾,加入4,6-二甲氧基嘧啶-2-胺0.08 mol,在60℃下反应4 h,产品总得率不低于75%。产品对植物病害菌有良好的抑制和杀灭作用。  相似文献   

6.
李祥祥  王丽芝  迟韵  刘敬  关建宁 《广东化工》2013,40(10):16-17,33
以间苯二酚和苯乙烯为原料,杂多酸盐1-(3-磺酸基)丙基-3-甲基咪唑磷钨酸盐([MIMPS]3PW12O40)为催化剂,催化合成标题化合物。考察了催化剂用量、反应物的摩尔比、反应时间等因素对产率的影响。最优的反应条件为:反应温度75℃,反应时间60 min,n(间苯二酚)∶n(苯乙烯)=1.5∶1.0,催化剂用量3%(按反应体系总质量计算),在此条件下,产物收率可达89.8%。对产品进行了熔点测定及1HNMR分析,确定合成的产物为目标产物。  相似文献   

7.
以间苯二酚、三氯甲苯和苄基氯为原料,通过两步反应合成2-羟基-4-苄氧基二苯甲酮。第一步采用以间苯二酚和三氯甲苯为原料,在十六烷基三甲基溴化铵作为相转移剂时,合成了中间体2,4-二羟基二苯甲酮,其反应的适宜条件为:反应原料n(三氯甲苯)/n(间苯二酚)比为1.4、滴加温度为60℃、反应温度为70℃、反应时间为0.5 h和催化剂用量为3.0 g/mol(以间苯二酚计),产品收率在95%以上。第二步采用以中间体2,4-二羟基二苯甲酮和苄基氯为原料,合成最终产物2-羟基-4-苄氧基二苯甲酮,结果表明,反应原料n(苄基氯)/n(2,4-二羟基二苯甲酮)比为1.0、Na2CO3为106.0 g/mol(以2,4-二羟基二苯甲酮计)、环已酮为40 mL和反应时间为6 h,产率在77%以上。得到的中间体和产物通过红外光谱、元素分析和1H-NMR进行表征。  相似文献   

8.
对4′-氯-2-硝基联苯的合成路线进行优化,以获得适合工业化生产的工艺路线。以对氯溴苯和邻溴硝基苯为原料,以Pd(dppf)Cl2为催化剂,依次经过格氏反应、Suzuki偶联两步反应合成4′-氯-2-硝基联苯。X-射线衍射测定了其晶体结构。在优化的反应条件下,4′-氯-2-硝基联苯的合成总收率≥82%,纯度98.8%;产物结构经IR、2为催化剂,依次经过格氏反应、Suzuki偶联两步反应合成4′-氯-2-硝基联苯。X-射线衍射测定了其晶体结构。在优化的反应条件下,4′-氯-2-硝基联苯的合成总收率≥82%,纯度98.8%;产物结构经IR、1H NMR、MS确证。该工艺绿色环保,条件温和,适合工业化生产。  相似文献   

9.
以联苯和乙酰氯为原料,通过傅克酰基化反应合成4-联苯乙酮,在醋酸体系中,4-联苯乙酮经Co-Mn-Br常压催化氧化,得目标产物联苯-4-甲酸。详细考察了催化剂用量、物料配比、氧气流速和反应温度对氧化反应的影响,确定较佳的工艺条件:n(Co)∶n(Mn)=1∶1,n(Co+Mn)∶n(Br)=1∶1,催化剂的用量为1.5%(原料的重量比),氧气流速为150 m L/min,反应温度80℃。在此条件下,联苯-4-甲酸产品收率为92.9%(以原料联苯计),纯度为99.5%(HPLC面积归一化法)。产物结构经过熔点、1H-NMR和MS表征。  相似文献   

10.
田苗  柴宗曦 《工业催化》2015,23(4):327-329
以(2S,4R)-4-羟脯氨酸为基础原料,以水为介质,利用三苯基膦和醇的Mitsunobu合成反应,改变其构型得到(2S,4S)-4-羟脯氨酸。此方法在现有合成路线基础上有所改进,在实验过程中探索反应物配比对各步反应收率的影响,得到实验的最优条件。并对产物进行表征及纯度分析,确定为(2S,4S)-4-羟脯氨酸,纯度为87.2%,收率93.3%。  相似文献   

11.
环保型溴虫腈纳米农药制剂的应用   总被引:2,自引:0,他引:2  
用硬脂酸对Ag/TiO2表面进行了改性,其表面由亲水性变为亲油性.将溴虫腈农药、改性Ag/TiO2和相应的添加剂混合制成颗粒分布较均匀、平均粒径约为100 nm的纳米农药制剂.溴虫腈纳米制剂光降解实验表明,在黑暗中稳定,在有光线的室内放置15 d的分解率为15.8%,在太阳光直射下放置3 d的分解率为69.0%.紫外光照22.5 h时,纳米制剂分解率是常规制剂的9.2倍.溴虫腈纳米制剂室内、田间毒力试验表明,纳米制剂比常规制剂具有更强的毒力,其LC50为8.95 mg•L-1,是乳油毒力的1.77倍.在田间药效对比试验中,施药剂量减少一半条件下,纳米制剂防治甘蓝斜纹夜蛾的田间防效优于溴虫腈乳油,药后1 d和3 d的校正防效分别高出4.89和3.05个百分点.土壤、植物的残留试验表明,纳米制剂在甘蓝、土壤中的消解较快,其t1/2分别为3.91 d和1.27 d,而溴虫腈SC的t1/2分别为 8.64 d和3.27 d.  相似文献   

12.
3-甲基吡啶和4-甲基吡啶的分离技术进展   总被引:1,自引:0,他引:1  
赵欢  肖国民 《化工科技》2004,12(4):52-56
3-甲基吡啶与4-甲基吡啶是生产高附加值精细化工产品的重要有机原料,广泛应用于医药、农药、染料、香料、饲料添加剂、食品添加剂、橡胶助剂及合成材料等领域。笔者综述了3-甲基吡啶与4-甲基吡啶混合体系的各种分离方法,并对其应用前景进行了展望。  相似文献   

13.
《Ceramics International》2020,46(5):6124-6128
Pesticides are generally utilized one after another for crop conservation, and this pesticide utilization oftentimes resulting in combined pollution of their residues in the environment. An experimental study was performed on the degradation of dinoseb and imidacloprid. In this research, GO/CuFe2O4–CdS nanocomposite was synthesized as a high-efficiency photocatalyst for the process of pesticides pollutants from water. Field Emission Scanning Electron Microscopy with Energy Dispersive X-ray (FESEM-EDX), X-Ray Diffraction (XRD), Vibrating-sample Magnetometer (VSM), and Fourier Transform Infrared spectroscopy (FTIR) analyses are applied to study the properties of this nanocomposite. Dinoseb and imidacloprid as pesticide materials have been utilized as water contaminants and their degradation performance using the synthesized photocatalyst is considered. The effect of initial pH, photocatalyst amount, initial pesticide concentration and degradation time are investigated in this research. The optimum values for both pesticides were as follows: pollutant concentration was 10 ppm, the nanocatalyst amount was 100 mg, irradiation time was 100 min and the pH of pesticide solution equaled to 8. The results showed that the GO/CuFe2O4–CdS nanocomposite is the efficient nanocatalyst for degradation of these pesticides.  相似文献   

14.
肖勇  梁雪松 《云南化工》2010,37(6):16-18,21
当温度超过50℃时,赤霉素A4+7(GA4+7)水溶液,容易分解而失去活性。研究表明:加入适量的农药助剂M,可以明显提高GA4+7水剂的稳定性,使其热贮分解率在5%以下,达到农药制剂热贮稳定性的要求。  相似文献   

15.
A series of 3-hydroxypyridine-4-one and 3-hydroxypyran-4-one derivatives were subjected to quantitative structure-antimicrobial activity relationships (QSAR) analysis. A collection of chemometrics methods, including factor analysis-based multiple linear regression (FA-MLR), principal component regression (PCR) and partial least squares combined with genetic algorithm for variable selection (GA-PLS) were employed to make connections between structural parameters and antimicrobial activity. The results revealed the significant role of topological parameters in the antimicrobial activity of the studied compounds against S. aureus and C. albicans. The most significant QSAR model, obtained by GA-PLS, could explain and predict 96% and 91% of variances in the pIC50 data (compounds tested against S. aureus) and predict 91% and 87% of variances in the pIC50 data (compounds tested against C. albicans), respectively.  相似文献   

16.
以4羟基联苯为原料,经过酯化、傅克酰基化反应、氨解、水解和脱水反应等步骤,合成制得液晶材料中间体4羟基4′氰基联苯。此合成方法操作简单,各步反应条件温和,总收率为47.7%,不产生含氰废水,有利于工业生产。  相似文献   

17.
农药由于毒性太强对人体危害比较大。近年来,研究发现农药中间体与金属化合物络合生成的金属配合物可以延长农药半衰期,降低对哺乳动物的毒性,提高其生物药效,为寻找绿色农药提供了依据。以农药中间体3-氨基-4-吡唑甲酸乙酯为主要研究对象,分别和氯化铜、氯化锌、氯化钡、硫酸亚铁铵4种金属化合物反应,合成4种新的金属配合物,采用红外光谱,核磁氢谱和单晶数据对合成的金属配合物进行分析。  相似文献   

18.
The lepidopteran genus Saturnia has three representatives in North America, S. walterorum, S. mendocino, and S. albofasciata. (E4,Z9)-Tetradecadienal (E4,Z9–14 : Ald) was identified as a sex pheromone component for all three species by combinations of coupled gas chromatography–electroantennogram detection (GC-EAD), GC–mass spectrometry (MS), and field trials. In field trials, all three species were strongly attracted to (E4,Z9–14 : Ald) as a single component. Small amounts of (Z)-9-tetradecenal (Z9–14 : Ald) also were found in extracts of all three species, but blends of this compound with E4,Z9–14 : Ald were no more attractive to male moths than E4,Z9–14 : Ald alone. Extracts of pheromone glands of female S. walterorum occasionally contained a third, trace compound eliciting responses from male antennae in GC-EAD experiments, but this compound was not identified. It is suggested that the three species can use the same, single component as a sex attractant because the flight period of S. albofasciata (fall) is different than that of the other two species (spring), whereas the geographic distributions of S. mendocino and S. walterorum overlap over only small portions of their ranges. Furthermore, the latter two species readily hybridize, so there may be minimal fitness cost to cross-attraction.  相似文献   

19.
Cytochrome P450-3A4 (CYP3A4) is a monooxygenase enzyme that plays a major role in the detoxification of bioactive compounds and hydrophobic xenobiotics (e.g. medicines, drugs, environmental pollutants, food supplements and steroids). Physiologically the monooxygenation reactions of this class II, microsomal, b-type heme enzyme, usually requires cytochrome P450 reductase, NADPH. A novel CYP3A4 biosensor system that essentially simplified the enzymatic redox processes by allowing electron transfer between the electrode and the enzyme redox centre to occur, without any need for the physiological redox partners, was developed for the detection of 2,4-dichlorophenol (2,4-DCP), a priority environmental pollutant and an endocrine disruptor. The biosensor, GC/Naf-Co(Sep)3+/CYP3A4/Naf, was constructed by encapsulating CYP3A4 in a Nafion-cobalt (III) sepulchrate (Naf-Co(Sep)3+) composite film on a glassy carbon (GC) electrode. The responses of the biosensor to 2,4-dichlorophenol, erythromycin (CYP3A4 native substrate) and ketoconazole (CYP 3A4 natural inhibitor) were studied by cyclic and square wave voltammetric techniques. The detection limit (DL) of the biosensor for 2,4-dichlorophenol was 0.043 μg L−1, which is by an order of magnitude lower than the EU limit (0.3 μg L−1) for any pesticide compound in ground water. The biosensor's DL is lower than the U.S. Environmental Protection Agency's drinking water equivalent level (DWEL) value for 2,4-DCP, which is 2 μg L−1.  相似文献   

20.
Wastewaterwith high NH4+-N is difficult to treat by traditional methods. So in this paper, a wild strain of photosynthetic bacteria was used for high NH4+-N wastewater treatment together with biomass recovery. Isolation, identification, and characterization of the microorganism were carried out. The strain was inoculated to the biological wastewater treatment unit. The impacts of important factorswere examined, including temperature, dissolved oxygen, and light intensity. Results showed that photosynthetic bacteria could effectively treat high NH4+- Nwastewater. Forwastewaterwith NH4+-N of 2300 mg · L-1, COD/N=1.0, 98.3% of COD was removed, and cell concentration increased by 43 times. The optimal conditions for the strain's cell growth and wastewater treatment were 30 ℃, dissolved oxygen of 0.5-1.5 mg · L-1 and a light intensity of 4000 lx. Photosynthetic bacteria could bear a lower C/N ratio than bacteria in a traditionalwastewater treatment process, but the NH4+-N removal was only 20%-40% because small molecule carbon source was used prior to NH4+-N. Also, the use of photosynthetic bacteria in chickenmanurewastewater containingNH4+-Nabout 7000mg· L-1 proved that photosynthetic bacteria could remove NH4+-N in a real case, finally, 83.2% of NH4+-N was removed and 66.3% of COD was removed.  相似文献   

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