首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
邻苯二酚烷基化合成邻乙氧基苯酚中试研究   总被引:2,自引:1,他引:2  
对邻苯二酚、氯乙烷法中试合成邻乙氧基苯酚的缩合反应工艺进行了研究,通过条件对比试验,对工艺参数进行寻优.  相似文献   

2.
农药中间体呋喃酚的合成研究(Ⅰ)   总被引:3,自引:0,他引:3  
本文报道了以邻苯二酚和异丁醛为原料,经过缩合、重排转位二步反应合成杀虫剂呋喃丹的主要中间体呋喃酚的方法,并探讨了各步反应的反应条件对产率的影响。  相似文献   

3.
以4-甲基邻苯二酚和溴乙酸甲酯为原料,经威廉森缩合反应合成了西瓜酮中间产物4-甲基邻苯二酚二乙酸二甲酯。研究发现适量KI的加入因与溴乙酸甲酯生成活性更高的碘乙酸甲酯可明显提高4-甲基邻苯二酚二乙酸二甲酯的收率,起到了催化剂的作用。研究首先通过熔点测定、NMR、IR和HLPC验证了合成产物的结构和纯度,然后研究了各种反应条件,特别是碘化钾的加入量对4-甲基邻苯二酚二乙酸二甲酯收率的影响,最后采用正交实验确定了反应的最佳条件:KI:C7H8O2(mol:mol)=0.75:1;C3H5BrO2:C7H8O2(mol:mol)=3.5:1;K2CO3:C7H8O2(mol:mol)=4:1;反应时间=6 h;反应温度=80℃。验证实验表明在此条件下4-甲基邻苯二酚二乙酸二甲酯的收率可达到94.7%,而对应的西瓜酮收率可达到67.6%。  相似文献   

4.
苯酚羟基化合成苯二酚反应过程酚焦油的生成与抑制   总被引:2,自引:0,他引:2  
对铁基复合氧化物催化苯酚羟基化合成苯二酚反应过程酚焦油的生成反应进行了模拟研究.在含邻苯二酚、对苯二酚和对苯醌的混合水溶液中,邻苯二酚比对苯二酚更容易缩合生成焦油,邻苯二酚能够还原对苯醌,反应时间延长,反应温度提高,加入对苯醌或者催化剂,会促进苯二酚生焦反应.对回收所得废催化剂进行了热失重分析(TG/DrTG),进一步验证了反应过程中沉积在废催化剂上的酚焦油更多的来自于邻苯二酚.红外光谱(IR)分析表明,1620 cm-1吸收峰的产生和强化进一步说明废催化剂上沉积的酚焦油含有典型的C=O结构.在羟基化反应液中加入亚硫酸氢钠可以抑制对苯醌和残留催化剂对苯二酚氧化缩合生成焦油的催化作用,从而减少了反应液中苯二酚的生焦反应.  相似文献   

5.
孙青斌  徐桂清  郝二军  李伟 《广东化工》2011,38(7):50+60-50,60
以邻苯二酚与环氧氯丙烷为原料,经环合、氧化、氧化、酰化、缩合、成盐等反应合成了治疗高血压和良性前列腺增生的药物甲磺酸多沙唑嗪。原料廉价,易得,反应条件温和,操作方便。  相似文献   

6.
以醋酸乙烯酯、乙醇、氯气为原料,采用一锅煮方法合成氯乙醛缩二乙醇,同时用正交实验法优化了关键步骤氯乙醛和乙醇的缩合反应条件,得到优化条件为:醋酸乙烯酯与乙醇的比为1:5,缩合反应时间3h,缩合反应温度60℃,中和到pH值为6,此条件下产品收率达83%.并且在相同的实验条件下对其它卤代乙醛缩二醇的合成进行了初步的探讨,产品收率在60~80%之间.  相似文献   

7.
氟磺酸树脂催化合成2-异丙基-1,3-苯并二噁茂的研究   总被引:1,自引:0,他引:1  
彭安顺  薛兆民 《辽宁化工》2003,32(6):231-232,235
以邻苯二酚和异丁醛为原料,氟磺酸树脂为催化剂合成了合成杀虫剂呋喃丹的中间体2-异丙基-1,3-苯并二噁茂。考察了原料配比、催化剂用量和带水剂用量等因素对缩合收率的影响。其最优工艺条件是:n(邻苯二酚):n(异丁醛):m(催化剂):v(带水剂)为1mol:1.5mol:10g:250ml,反应在回流温度下进行,反应时间约4h,收率可达92.6%。催化剂可重复使用。  相似文献   

8.
1,1,3,3-四甲基-1,3-二乙烯基二硅氧烷(即双封头)通常是先由钠缩合反应合成二甲基乙氧基乙烯基硅烷(以下简称单封头),再经水解得到[1-2]。在钠缩合反应合成单封头的反应中,对不同条件下,各种因素对钠缩合反应收率的影响进行研究,考察了路易斯酸作催化剂对钠缩合反应收率的影响,发现路易斯酸作催化剂使钠缩合反应收率得到明显的提高,高达77.6%。在水解反应中通过正交实验法对其工艺条件进行优化,选出最佳工艺条件,其反应收率可达90.7%。  相似文献   

9.
李富志  韩会娟  李伟  王伟 《广州化工》2009,37(8):183-184
1-(1,4-苯并二噁烷-2-甲酰基)哌嗪为甲磺酸多沙唑嗪的重要中间体,以邻苯二酚与环氧氯丙烷为原料,经环合、氧化、氯化、酰化、缩合四步反应合成了治疗高血压和前列腺增生药物甲磺酸多沙唑嗪的关键中间体1-(1,4-苯并二噁烷-2-甲酰基)哌嗪。原料廉价,易得,反应条件温和,操作方便。  相似文献   

10.
研究了邻苯二酚在不同条件下的Friedel-Crafts乙酰化反应。利用三氟化硼乙醚溶液作催化剂,乙酸为乙酰化试剂,合成了3,4-二羟基苯乙酮,并在此基础上,进一步对反应条件进行了优化。优化的条件为:n(三氟化硼)∶n(邻苯二酚)=1.2∶1.0,反应温度为80℃,反应时间为4 h,优化条件下,3,4-二羟基苯乙酮的收率达66.7%。  相似文献   

11.
我国脂肪酸的生产和应用   总被引:3,自引:0,他引:3  
简要介绍脂肪酸的分类、原料来源、生产工艺、品种以及用途。并对我国脂肪酸的生产现状进行了分析。重点介绍了脂肪酸在我国橡胶工业中、塑料助剂等领域的应用,脂肪酸甲酯作为表面活性剂在不同领域的广泛应用,最后还简述了癸二酸和改性醇酸树脂应用。  相似文献   

12.
酸液体系的研究现状分析和现场应用   总被引:1,自引:0,他引:1  
唐立杰 《广东化工》2010,37(11):221-222,226
酸化解堵与压裂改造相比,它具有施工相对简单和成本相对较低等特点,所以酸化解堵是一项各油田广泛使用的油气田增产技术。酸化解堵技术已有将近100历史,现已研制出具有不同特点的酸液体系,如乳化酸、泡沫酸、固体酸、多氢酸等,基本能满足复杂地质条件对酸液的要求。  相似文献   

13.
油酸的精制研究   总被引:5,自引:1,他引:4  
油酸酰胺是一种很好的塑料添加剂 ,可用作塑料加工成型时的脱膜剂、润滑剂。油酸的原料来源很广 ,牛油、羊油、猪油等动物油油脂以及大豆油、花生油、棕榈油等植物油脂中都含有大量的油酸。由于油酸的来源和生产方法多种多样 ,因此其所含的脂肪酸种类及含量都不尽相同。除油酸外 ,还有亚油酸、亚麻酸等高不饱和脂肪酸。针对油酸中因含有大量的多不饱和组分如亚油酸、亚麻酸而容易产生氧化泛黄的问题 ,采取了尿素络合法对原料油酸进行精制 ,以减少原料中亚油酸、亚麻酸组分的含量。经气相色谱验证 ,产品达到了应用指标 ,提高了产品的抗氧性。  相似文献   

14.
Biohydrogenation intermediates (BHI) including conjugated linoleic acid (CLA) isomers are formed during ruminal biohydrogenation of polyunsaturated fatty acids (PUFA) in ruminants. Although many studies have examined the anticarcinogenic effects of CLA, few studies have reported the anticarcinogenic properties of BHI in their natural form found in dairy and beef fats. The present study compared the growth‐inhibitory effects of fatty acids from beef perirenal fat (PRF) or subcutaneous fat (SCF) with low or high levels of BHI in MCF‐7 human breast cancer cells. Cells were exposed for 72 h to media containing increasing doses (50 to 400 μM) of different beef fat treatments. Fatty‐acid analysis showed that BHI were readily incorporated into cell phospholipids (PL) in a treatment‐dependent manner, but higher BHI in PL did not consistently inhibit growth. Culturing with low‐BHI PRF or high‐BHI PRF did not lead to growth inhibition, but low‐BHI SCF inhibited growth, and inhibition was further increased by high‐BHI SCF. Other classes of fatty acids may, therefore, be interacting with BHI resulting in differential effects on growth inhibition in human breast cancer cells.  相似文献   

15.
介绍了磷钼杂多酸的合成。通过正交试验探讨了反应物料量比、三氧化钼浓度、反应温度和反应时间对产物产率的影响。结果表明,最适宜的反应条件为:反应物量比n(三氧化钼)∶n(磷酸)=12∶1.0、反应温度t=70℃、反应时间7 h、三氧化钼与水的质量比1∶8。经红外光谱分析及熔点测定确定所得产品为磷钼杂多酸化合物。并以磷钼杂多酸取代硫酸作催化剂制备乙酸乙醋来研究其催化活性,并与硫酸做催化剂进行对比实验收率为70.75%,超过硫酸催化剂水平。  相似文献   

16.
This study aimed to evaluate the fatty acid profiles of sunflower oil extracted from hybrid grains produced and stored in different environments. The trials were conducted in Teresina (Piauí), Vilhena (Rondônia), and Jaguariúna (São Paulo) in randomized complete block design with 4 replicates. After harvesting, grains from 1 high oleic and 3 traditional hybrids were packed in kraft paper bags and stored in a covered shed and in a cold chamber up to 12 months. The fatty acid profiles were determined by gas chromatography after 0, 4, 8, and 12 months of storage. Analyses of variance were conducted in a split‐plot design, with hybrids being considered as whole plots and storage times as subplots. Tukey's test was performed to compare hybrids and regression analyses for storage times. The initial fatty acid profile of the grains of the same hybrid varied depending on the production location. The grain storage of high oleic and traditional sunflower hybrids during 12 months in covered shed and in cold chamber resulted in little changes in oil fatty acid profiles, regardless of the initial contents. These changes occurred only for linoleic and palmitic acids.  相似文献   

17.
This study aimed to verify whether the fatty acid profiles of mid-oleic genotypes grown in the tropical region of Brazil fit the Codex Alimentarius and to examine the possibility of using traditional inbred lines to produce high-oleic hybrids. For this purpose, we assessed the fatty acid profile of six mid-oleic hybrids grown in environments with different minimum temperatures during oil formation in the achenes. The tests were conducted between 2015 and 2017 in an experimentally randomized complete block design with four replications. The oleic, linoleic, palmitic, and stearic acid contents were determined using gas chromatography. The mid-oleic hybrids presented varying levels of fatty acids, with oleic acid ranging between 43.6% and 84.6%, linoleic acid between 8.5% and 45.6%, palmitic acid between 3.9% and 5.7%, and stearic acid between 2.2% and 6.2%. Some of the fatty acid values were outside the ranges established by the CODEX STAN 210-1999 and were characteristic of high-oleic type sunflowers. This finding shows that we can take advantage of the potential of combining traditional inbred lines to produce high-oleic hybrids for faster and more economical breeding programs in these environments.  相似文献   

18.
The objective of this work was to evaluate the quality of the oil extracted from sunflower achenes grown in Campo Novo de Parecis, the main producing region of Brazil, to optimize its use by the processing and food industries. In addition, the fatty acid profiles of the oil were checked for their adherence to the CODEX STAN 210–1999. Traditional and high-oleic genotypes were grown between 2014 and 2017 during trials with a randomized complete block experimental design with four replications. The contents of oleic, linoleic, palmitic, and stearic acids were determined using gas chromatography. The fatty acid profiles of traditional genotypes were observed to be outside the ranges established by the CODEX, with an oleic acid content above 39.4% and linoleic, palmitic, and stearic acid values lower than 48.3%, 2.7%, and 5.0%, respectively, as well as high-oleic sunflower oil with a stearic acid content of less than 2.6%. The availability of this information can, on the one hand, positively impact industries and encourage the use of better quality raw materials that are more technologically and nutritionally adequate. On the other hand, the commercialization of sunflower oil with a fatty acid profile outside the ranges established by CODEX can be difficult, because the contents are out of specification due to the climatic conditions in the cropping region.  相似文献   

19.
采用廉价的浓硫酸为催化剂,氧气为自由基捕集剂,以十二酸为原料,经氯化合成α-氯代十二酸。系统考察了反应温度、催化剂用量、氯气流量、氧氯比、反应时间等因素的影响,得到最佳工艺条件:十二酸20 g,在反应温度135℃、催化剂10%、氯气流量50 mL·min-1、vO2/vCl2=1∶2、反应时间3 h,可实现十二酸基本完全转化,目标产物α-氯代十二酸选择性达到94.5%。  相似文献   

20.
在无有机溶剂、无相转移催化剂条件下,以草酸作助剂,采用磷钨酸催化过氧化氢氧化环己醇的方法来制备己二酸。考察了磷钨酸用量、反应时间、反应温度、过氧化氢用量及草酸用量对己二酸的分离产率的影响,得到最佳工艺条件,即环己醇10.51 mL、磷钨酸0.6 mmol/L、草酸1.0 mmol/L,H2O2(30%)70 mL,温度85℃、时间8 h,己二酸的最大分离产率为77.83%,纯度为99.9%。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号