共查询到19条相似文献,搜索用时 62 毫秒
1.
2.
3.
对甲基丙烯酸与二氯亚砜反应制备分离的方法作了改进,提高了分离纯度,研究了反应的各个条件.实验得出反应的最佳反应条件为:二氯亚砜与甲基丙烯酸的进料比为2:1,反应温度为60-64℃,回流6个小时. 相似文献
4.
5.
采用三氯化磷作氯化剂合成异丁酰氯,研究确定了最佳物料比、反应温度和反应时间、获得了较高的产品收率,中试装置工艺简单,操作方便,能耗低,无三废排放,产品质量稳定,同时建立了异丁酰氯的分析方法。 相似文献
6.
7.
5-氯甲酰氧基异肽酰氯的制备 总被引:4,自引:0,他引:4
以三光气(简称BTC)为酰氯化剂,与 5 -羟基异酞酸在复合催化剂作用下制备了 5- 氯甲酰氧基异肽酰氯(简称CFIC),收率最高可达 42 .3%。分析了反应条件的改变对产品收率的影响。反应物量比R〔n(三光气)∶n(5- 羟基异酞酸)〕≤1 .1时,产品收率很低,几乎得不到产品; 1. 11 7时,影响不大。溶剂极性越大,反应越快,收率越高。复合催化剂(三乙胺 /咪唑、吡啶 /咪唑)的催化效果远远优于单一催化剂(N,N -二甲基甲酰胺、三乙胺、吡啶和咪唑)。反应适宜在 5 ~20℃操作,温度高于 30℃时,反应很难进行。反应时间较短时,对产品收率影响较大,当时间大于 24h后,影响不大。利用正交实验确定的最佳工艺条件为:反应物量比为 1. 67;催化剂为m(咪唑)∶m(吡啶) =1∶4及m(吡啶+咪唑)∶m(三光气) =0. 08∶1;反应温度5~10℃。用红外光谱仪分析产品的主要官能团:在 1785. 24、1764 .12、1603 .20cm-1和 1557. 99cm-1处有强吸收峰,它们分别为Ar—OCOCl、Ar—COCl与三取代基苯环。用高效液相色谱仪测得w(CFIC) =99. 4%,用数字熔点仪测得产品熔点为 56. 7~57. 0℃。推测了三光气在催化剂作用下的反应机理。 相似文献
8.
本文综述了3,4,5-三甲氧基苯甲酰氯的理化性质,测定方法,制备方法及应用领域。 相似文献
9.
《精细化工原料及中间体》2008,(4)
特戊酰氯的质量对合成药物的质量和收率有很大影响。氯化工艺特别是选择恰当的氯化剂很关键,目前主要使用的氯化剂有三氯化磷、氯化亚砜、光气等。国外产品主要采用光气法,成本高,质量好,有尾气处理问题,环保问题严重。我国特戊酰氯生产主要采用三氯化磷法,产品质量标准低,在合成医药产品中受到限制,主要用于农药领域。 相似文献
10.
酰卤通常采用对应的羧酸作为原料与卤化试剂发生取代反应的方法而制得,制备酰氯的常用试剂包括氯化亚砜、三氯化磷、五氯化磷、光气、固体光气作为原料,使用含磷氯化试剂作为酰氯化试剂,存在含磷废水或二氧化硫等污染物环保压力较大的缺点。为了确定采用光气法合成棕榈酰氯最佳的工艺条件,本研究中对光气法合成棕榈酰氯的工艺条件进行了研究,以棕榈酸和光气为原料、N,N-二甲基甲酰胺为催化剂,一步反应合成棕榈酰氯,确定了最佳的反应条件:催化剂投料比例1%,棕榈酸与光气配比1∶1.1,反应温度65℃,反应时间3 h。该条件下棕榈酰氯的纯度可达到98.2%。本方法避免使用含硫或磷的酰氯化试剂,操作工艺简单、反应可控、成本较低、而且产物的纯度和纯度都较高,特别适用于大规模工业化生产。 相似文献
11.
Silke Frömel Georg Radermacher Birgit Wibbeling Constantin G. Daniliuc Timothy H. Warren Gerald Kehr Gerhard Erker 《Israel journal of chemistry》2015,55(2):210-215
The intramolecular frustrated phosphane/borane Lewis pair Mes2PCH2CH2B(C6F5)2 ( 3 ) reacts with acetyl chloride to give a 1 : 1 mixture of the FLP-ketene adduct, 6a , and the FLP-HCl addition product, 7 . Similarly, the acyl chlorides phenylacetyl chloride and isobutyryl chloride react with 3 to give the respective substituted FLP ketene adducts, 6b and 6c , with HCl elimination. A series of aroyl chlorides reacts with 3 by formation of the respective aroyl-phosphonium/chloroborate zwitterions, 11a – d . The hetero-aromatic furoyl chloride reacts with 3 in a more complicated, but mechanistically probably closely related pathway, to form the 2 : 1 reaction product, 14 . Most of the products were characterized by X-ray diffraction. 相似文献
12.
13.
14.
A method is proposed for producing fatty acid esters of thermomechanical pulp (TMP) using fatty acids of intermediate chain length (C6-C12). The end objective is to use a stream of fatty acids produced via refining tall oil from Alberta's pulping mills. Depending on the degree of modification, these treated materials can serve either as reinforcement or as copolymers in composite applications. The effect of reaction conditions—reaction time, reaction temperature, fatty acyl concentration, and fatty acid chain length—on the degree of substitution of the pulp samples was studied. The reaction conditions were applied for each fatty acyl chloride and the pulp samples were characterized using X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, force tensiometry, time-of-flight secondary ion mass spectroscopy, atomic force microscopy, and thermal gravimetric analysis. The degree of substitution (DS) plateaued after two hours at a concentration of 0.25 M of hexanoyl chloride. These conditions were used for the other systems studied. The esterification of the pulp samples was heterogeneous as evident from both the AFM and SIMS images, because of the presence of lignin on the surface. Nevertheless, based on adhesion forces measured using AFM, the surface of the modified pulp samples was less polar. This was also confirmed via contact angle measurements. Also, the changes in chemical functionality were studied using FTIR and XPS with the appearance of peaks characteristic of C?O (esters) and an increase in intensity of the alkyl shifts, respectively. Finally, it was found that esterification significantly improved the thermal properties of the pulp samples. 相似文献
15.
为提高联合制备氯化亚砜和三氯氧磷间歇工艺的生产效率,采用多段釜式或塔式连续反应器,以三氯化磷为原料,通入二氧化硫和氯气,连续合成三氯氧磷和氯化亚砜。实验结果表明:氯化亚砜含量达到国家标准一级品指标,三氯氧磷质量分数达到99%以上,产品收率>90%。该工艺具有收率高、质量好、连续生产的优点,宜于规模化生产,是一种值得推广应用的工业制备方法。 相似文献
16.
17.
18.
19.
三氯氧磷及其衍生产品的生产及应用综述 总被引:3,自引:0,他引:3
简要介绍了三氯氧磷的生产方法,重点对三氯氧磷衍生产品中具有代表性的几种产品的生产与应用情况进行了综述,并根据国内生产现状提出了几点建设性的建议。 相似文献