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1.
研究了四溴双酚A双缩水甘油醚的合成方法,探索了不同原料摩尔比、溶剂、反应温度、第一步反应中碱的用量以及第一步反应时间对反应的影响,并对产品进行了环氧当量的测定。  相似文献   

2.
用四溴双酚S(TBS)为原料,以滴加方式加入醚化剂烯丙基氯,在NaOH水溶液中用十六烷基三甲基溴化铵(CTAB)催化醚化法和其它表面活性剂促进醚化法合成了收率、纯度均较高的阻燃剂四溴双酚S双烯丙基醚(ATBS)。研究了催化剂用量、滴加时间、异丙醇用量、水用量对ATBS收率及纯度的影响。在烯丙基氯用量为15 mL、TBS为28.3 g、CTAB为0.1~0.18 g、反应温度65~75℃、保温时间4 h,ATBS收率可达95.5%~97.5%,纯度为95.5%~98.0%。当n(烯丙基氯)∶n(TBS)=1∶2.5、反应温度80~90℃、保温时间8 h,表面活性剂DBS为0.8~1.0 g、OP-10为0.5 g、OS-15为0.8 g时,ATBS最佳收率分别为95.2%、97.3%和95.5%,纯度分别为94.0%、92.7%和90.1%。  相似文献   

3.
溴系阻燃剂在环境及人体中的存在和代谢转化   总被引:9,自引:0,他引:9  
溴系阻燃剂的广泛使用及其对环境和人体的危害,受到人们的广泛关注。本文简要介绍了在环境与生态系统及人体中存在的三种主要溴系阻燃剂:多溴联苯醚、六溴环十二烷和四溴双酚A,重点评述了它们在环境介质(污水、淤泥及沉积物)、生物体(微生物及动物)、人体中及光热作用下的代谢与转化,并详细介绍了其代谢途径及代谢产物。  相似文献   

4.
华川  杨晓健  刘兴丽  马培华  周清娣 《化学通报》2015,78(12):1102-1107
以溴代丁二酮为原料,分别从加料方式、酸度、原料摩尔比等方面优化了溴甲基取代甘脲的合成工艺。在溴代丁二酮与尿素的摩尔比为1∶5、加入水-乙醇混合溶剂、搅拌24h后加入溶剂体积2.5%的三氟乙酸、反应48h条件下,产率达60.8%。相对文献[10],本法产率提高了20%~30%。并利用溴甲基取代甘脲与多聚甲醛在氢溴酸-冰乙酸体系下75℃恒温反应1h,得溴甲基取代甘脲二醚,产率达65.5%。在利用核磁共振技术对化合物的结构及性能进行检测和表征的同时,使用X射线单晶衍射技术确定了其中两个化合物的晶体结构。  相似文献   

5.
李志刚 《分析测试学报》2017,36(10):1260-1264
采用固相萃取/超快速液相色谱-串联质谱技术(SPE/UFLC-MS/MS)建立了纺织品中四溴双酚A的测定方法。样品经甲醇超声提取,C_(18)-SPE净化后分析,在串联质谱电喷雾(ESI)离子多反应监测(MRM)模式下检测,以保留时间以及特征离子对进行定性、定量分析。实验结果表明,四溴双酚A在1.0~100.0μg/L范围内呈良好的线性关系。称样量为1.0 g时,方法的定量下限为1.0μg/kg。平均回收率为80.9%~95.3%,相对标准偏差(RSDs)为2.3%~5.9%。所建方法快速、准确、灵敏,可用于纺织中四溴双酚A的分析测定。  相似文献   

6.
建立了超声辅助-分散液相微萃取/高效液相色谱测定沉积物中双酚A,四溴双酚A,四溴双酚A双烯丙基醚,四溴双酚A双(2,3-二溴丙基)醚的方法。对萃取剂与分散剂的种类与用量、超声时间、盐效应及p H等萃取条件进行了优化。在优化的条件下,此方法的线性范围为0.1~100 mg/L,线性相关系数(r)为0.9996~0.9999。样品平均回收率为83%~91%,相对标准偏差为1.8%~4.9%。检出限(S/N=3)为0.01~0.15μg/L。方法可用于实际水库沉积物中双酚A及其衍生物的测定。  相似文献   

7.
肖进进  富玉  林舒  张姝 《色谱》2011,29(2):168-171
建立了电子产品中四溴双酚-A(TBBP-A)的气相色谱-质谱联用(GC-MS)检测方法。样品经丙酮提取后挥发至干,经二氯甲烷重新溶解后,用碳酸钾溶液反提取,反提取液与乙酸酐衍生化反应。衍生产物经正己烷提取后,采用GC-MS进行分析。结果表明,方法的线性范围为0.25~5.0 mg/L,相关系数为0.996;方法的检出限为0.05 mg/kg;平均回收率为87.3%~104.1%,相对标准偏差为5.6%~8.5%。该方法准确、灵敏,可用于实际电子产品中四溴双酚-A的分析。  相似文献   

8.
溴系阻燃剂是目前全世界范围内使用的主要阻燃剂,常用的有十溴联苯醚、四溴双酚A、四溴双酚A-双(2,3-二溴)丙醚、六溴环十二烷、三溴苯酚、十溴联苯乙烷等。溴系阻燃剂的分解温度大多在200~300℃左右,与各种高聚物的分解温度匹配,因此能在最佳时刻以气相及凝聚相同时起到阻燃作  相似文献   

9.
建立了一种同时检测鸡蛋中四溴双酚A(TBBP A)、六溴环十二烷(HBCD)和多溴联苯醚(PBDEs)及其衍生物羟基多溴联苯醚(OH-PBDEs)和甲氧基多溴联苯醚(MeO-PBDEs)的凝胶渗透色谱(GPC)-分散固相萃取(DSPE)-液相色谱-串联质谱(HPLC-MS/MS)和气相色谱-负化学源质谱(GC-NCI/MS)的检测方法。样品经正己烷、二氯甲烷(1∶1,V/V)加速溶剂萃取,凝胶渗透色谱净化后,经100 mg十八烷基键合硅胶(C18)分散固相萃取吸附剂去除杂质,液相色谱-串联质谱和气相色谱-负化学源质谱方法测定,外标法定量。在蛋白和蛋黄样品中添加1.0或5.0μg/kg的目标物,其回收率分别为64.5%~97.2%和65.6%~109.2%(除BDE-85为54.8%,OH-BDE-137为47.4%外),相对标准偏差小于20.2%,定量限为0.01~0.2μg/kg。  相似文献   

10.
溴化苄的合成工艺研究   总被引:1,自引:0,他引:1  
以二苄醚和氢溴酸为原料,SO42-/TiO2为催化剂,环已烷为带水剂,合成了溴化苄。实验分别考察了反应物摩尔比、反应时间、反应温度、带水剂的用量,催化剂的使用量等因素对溴化苄收率的影响,得出了用此方法合成溴化苄的最佳反应条件:氢溴酸与二苄醚的摩尔比为3:1,反应时间为8 h,环已烷为8 mL,SO42-/TiO2催化剂的用量为0.5 g,溴化苄的收率达80.2%。  相似文献   

11.
Tetrabromobisphenol A is the most widely used brominated flame retardant. A sensitive and selective enzyme-linked immunosorbent assay (ELISA) for the detection of tetrabromobisphenol A was developed. The limit of detection and the inhibition half-maximum concentration of tetrabromobisphenol A in phosphate buffered saline with 10% methanol were 0.05 and 0.87 ng mL−1, respectively. Cross-reactivity values of the ELISA with a set of important brominated flame retardants including tetrabromobisphenol A-bis(2,3-dibromopropylether), 2,2′,6,6′-tetrabromobisphenol A diallyl ether, hexabromocyclododecane, 1,2-bis(pentabromodiphenyl) ethane, 1,2-bis(2,4,6 tribromophenoxy) ethane, bis(2-ethylhexyl)-3,4,5,6-tetrabromophthalate, 2-ethylhexyl-2,3,4,5-tetrabromobenzoate, and polybrominated diphenyl ethers were <0.05%. Concentrations of tetrabromobisphenol A determined by ELISA in the soils from farmlands, the soils from an e-waste recycling site, and the sediments of a canal were in the range of non-detectable–5.6 ng g−1, 26–104 ng g−1 and 0.3–22 ng g−1 dw, respectively, indicating the ubiquitous pollution of tetrabromobisphenol A. The results of this assay for 16 real world samples agreed well with those of the liquid chromatography–tandem mass spectrometry method, indicating this ELISA is suitable for screening of tetrabromobisphenol A in environmental matrices.  相似文献   

12.
以4,4'-二硝基-6,6'-二甲基-2,2'-联吡啶-N,N'-二氧化物为起始原料,经过三氟乙酸酐酯化、羟甲基化、氢溴酸溴甲基化及亚氨基二乙酸二乙酯氢胺基甲基化合成了4,4'-二溴-6,6'-二(N,N-二(乙氧基羰甲基)氨甲基)-2,2'-联吡啶。通过熔点、红外光谱、核磁共振、高效液相色谱、高分辨质谱测试技术表征了该化合物的结构,为合成时间分辨荧光免疫分析新型双功能螯合剂提供了重要中间体。  相似文献   

13.
《Mendeleev Communications》2022,32(4):449-451
One-pot synthesis of cyclopentane-fused 5'-aryl-4- cycloalkylamino-2,2'-bipyridines based on the neat (200 °C) reaction of 3-(4-bromopyridin-2-yl)-1,2,4-triazines with enamines is reported. In the course of the transformation, consecutive aza-Diels–Alder reaction and nucleophilic substitution of bromine atom under the action of the liberating amine occur. The possibility of the solvent- and catalyst-free replacement of 4-positioned bromine atom in 2,2'-bipyridines by amino moieties was demonstrated.  相似文献   

14.
Summary: In the present work, a methodology of synthesis and characterization of the monomer 2,2′ diallylbisphenol-A (ABFA) was developed, aiming at getting a precursor, with adequate purity, for obtaining cross-linked membranes based on sulphonated poly(arylene ether sulphone)s. The monomer synthesis involved the synthesis of 2,2′ bis(4-allyloxiphenyl)propane (Bisphenol-A, diallyl ether - BFAAE), from Bisphenol-A (BFA), followed by Claisen rearrangement of BFAAE, for the production of the target compound 2,2′ diallylbisphenol-A (ABFA). All the compounds, reagent BFA and obtained products, intermediate product BFAAE and final product ABFA, were characterized by FTIR (Fourier Transform infrared spectroscopy), TGA (Thermo-gravimetric analysis) and HPLC (High-performance liquid chromatography). The compound BFAAE was obtained with a yield of 94.5% and a purity of 97.3%, the latter characterized by TGA and by HPLC. The structure of the product was confirmed by FTIR. The thermal Claisen rearrangement process was conducted by using Differential Scanning Calorimetry (DSC) technique, from a factorial experiment planning, with two factors and three levels, with temperature and time being the variables. The above cited techniques were used for monitoring the Claisen rearrangement and for the characterization of the final product. The best results yield ABFA purity between 85 and 90%, approximately, for 220 °C/60min, 230 °C/30min and 210 °C/90min conditions. The obtained results suggest that, in the studied range, polymerization and degradation of the monomer ABFA occur, simultaneously to its formation.  相似文献   

15.
Six ladder or partly ladder polymers have been prepared by the condensation reactions of combinations of two diaminodithiophenols, 4,6-diamino-1,3-dithiophenol and 3,3′-dimercaptobenzidine, with three tetrachloroquinoxaline derivatives, 2,3,7,8-tetrachloro-1,4,6,9-tetraazaanthracene, 2,2′,3,3′-tetrachloro-6,6′-bisquinoxaline, and 2,2′,3,3′-tetrachloro-6,6′-diquinoxalyl ether, with the use of dimethylacetamide, hexamethylphos phoramide, and polyphosphoric acid as reaction media. The polymers thus obtained are highly colored, powedery materials which are slightly soluble in methanesulfonic acid and concentrated sulfuric acid. These polymers (ηinh > 1) show good thermal stability.  相似文献   

16.
微波辅助二苯并-18-冠-6的合成   总被引:1,自引:1,他引:0  
陈凯  李鸿波  刘铠  刘浪  吴毅  马昌鹏  张永岗 《应用化学》2011,28(12):1453-1455
以邻苯二酚与二甘醇二取代物为原料,氢氧化钾为碱和模板剂,在微波辅助下,采用“一锅煮”法合成二苯并-18-冠-6。 经单因素及正交实验考察了原料、溶剂、时间、温度和功率对反应收率的影响,获得了最佳的工艺条件:以邻苯二酚与二氯乙醚为原料,二甲亚砜为溶剂,反应温度70 ℃,时间60 min,功率500 W,收率可达46.3%。  相似文献   

17.
Various routes were examined for the synthesis of chiral biphenyl species that are substituted at the 2,2', 4,4' and 6,6' positions. Because the biaryl bond is tetrasubstituted, many coupling reactions were not suitable. The most reliable coupling reaction proved to be the Ullmann, which gave the desired product in 82% yield. The products were required as the starting point for the preparation of chiral materials using these as the monomer. For this reason, a route was required that produced large quantities of both enantiomers. The two enantiomers were resolved at the penultimate step by the use of chiral HPLC. A complicating feature proved to be the necessity to have a reactive group at the 4,4' positions, which would permit polymerization though this point. Ultimately, we employed an Ullmann coupling on a dibrominated arene, which occurred selectively at the more hindered bromine by virtue of the directing effect of an ortho ester substituent.  相似文献   

18.
Di-μ-chlorobis(π-cycloocta-1,5-diene)diiridium, (I), reacts with allyl alcohol to give a complex, (II), of (I) and diallyl ether and byproducts: propene, propanal and diallyl ether. The same complex is readily obtained by direct reaction of (I) and diallyl ether. Some physicochemical properties (II) are described (IR spectra, stability, reactivity, etc.). Its structure is discussed, and a mechanism for the transformation of allyl alcohol during the reaction is given.  相似文献   

19.
脂肪腈是一类非常重要的化工原料和中间体,被广泛应用于医药、农用化学品、染料和合成树脂等领域.在诸多合成脂肪腈的路线中,脂肪醇氨氧化制备脂肪腈的路线使用可源于生物质资源的脂肪醇为原料,有助于“碳中和”和“碳达峰”目标的实现;同时,该反应副产物为水或氢气,符合“绿色”可持续发展的要求,具有重要的研究价值.根据脂肪醇氨氧化制备脂肪腈的过程中是否需要向体系中提供氧气,氨氧化过程可分为需氧氧化-氨化反应和脱氢氧化-氨化反应两类.需氧氧化-氨化反应在均相催化体系和非均相催化体系中均具有相关研究,而脱氢氧化-氨化反应的研究则主要集中在非均相体系中.按照以上分类,综述了脂肪醇氨氧化制备脂肪腈催化体系的研究进展,分析了不同种类催化体系的优势与尚存在的不足,并展望了该反应催化体系未来发展的方向.  相似文献   

20.
One step nickel-catalyzed electroreductive homocoupling among 2-bromopicolines and 2-bromopyridine has been investigated by our group in an undivided cell and using zinc or iron as sacrificial anode. In this work, it was developed mono and dihalopyridines coupling to obtain possible products from heterocoupling. A series of reactions were carried out in order to develop a synthetic method for the preparation of unsymmetrical 2,2′-bipyridines and 2,2′:6′,2″-terpyridines. Statistical yields (50%) were observed for 2-bromopyridines/2-bromo-6-methylpyridine heterocoupling. In a preliminary study devoted to terpyridines preparation, good results were obtained for 2,6-dihalopyridines homocoupling, affording 2,6-dichloro-2,2′-bipyridine (46%) and 2,6-dibromo-2,2′-bipyridine (56%), at controlled reaction time. At major reaction time, it was observed that the direct electroreduction of the 2,6′-dihalo-2,2′-bipyridines intermediates and 2,6″-dihalo-2,2′:6′,2″-terpyridines products on the cathode surface. A reasonable isolated product yield of 6,6″-dimethyl-2,2′:6′,2″-terpyridine (10%) was only observed in the reaction between 2,6-dichloropyridine and 2-bromo-6-methylpyridine (1:2).  相似文献   

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