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以DMF作溶剂,在四丁基氟化铵 (TBAF)存在下,对甲基苯基三甲硅基醚(1)和4,4'-二氯二苯砜(2)于100 ℃反应1 h,合成了4,4'-二(4-甲基苯氧基)二苯砜(3),产率为92%;加入催化量的N-溴代丁二酰亚胺(NBS)并在光照条件下,与氧气反应得到中间体-4,4'-二(4-羧基苯氧基)二苯砜(4),其产率达90%;将化合物4与二氯亚砜反应合成目标产物4,4'-二(4-氯甲酰基苯氧基)二苯砜(5),总收率为74.5%(以对甲基苯基三甲硅基醚为基准计算).  相似文献   

3.
对甲基苯基三甲硅基醚;二氯二苯砜;二(氯甲酰基苯氧基)二苯砜;合成  相似文献   

4.
变温核磁研究杂多酸催化芳烃磺化砜   总被引:1,自引:0,他引:1  
  相似文献   

5.
聚醚酮醚酮酮;4;4'-二苯氧基二苯砜、4;4'-二苯氧基二苯酮、对苯二甲酰氯三元共聚物的合成;聚醚砜醚酮酮;低温溶液浓缩聚  相似文献   

6.
4,4′-二羟基联苯是染料的稳定剂和高聚物中间体,也是制备烷氧基取代的联苯液晶的重要前体。4,4′-联苯二磺酸钠盐的碱熔,在催化剂存在下4,4′-二卤代联苯(X=Cl,Br)的水解,以及烷基取代的4,4′-二羟基联苯的去烷基化等已有的制备方法均需较高的温度、特殊催化剂及设备。通过卤代芳烃催化配合的制备方法,成本较高。用联苯胺盐酸盐重氮化后再水解的制备方法,则认为重氮化时盐酸中不可含有硫酸,因为联苯胺硫酸盐不易溶解。  相似文献   

7.
本文用(Ph_3P)_2PdCl_2为催化剂,合成了1,4-丁炔二醇(BD)与4,4-二乙炔联苯(DEBP)共聚物。对用不同比例的两种单体得到的共聚物测定了比重(d_4~(25)、溶胀度(θ_D)、最良溶剂及相邻两交联点之间的平均分子量(M_c)。实验表明,在两种单体摩尔比中,DEBP用量越多,共聚物中泡状微孔越多,颜色越淡,溶胀度和比重越小,交联度越大;DEBP/BD(摩尔比)大于1/5时,共聚物的最良溶剂为苯,溶度参数为9.15卡~(0.5)·cm~(-1.5),是1/10时,其最良溶剂为乙醇,溶度参数是12.7卡~0.5·cm~(-1.5)。对共聚物还做了红外光谱表征。  相似文献   

8.
以医药中间体合成过程中产生的副产物4,4′-二甲基联苯为原料,经氯代反应生成4,4′-双(三氯甲基)联苯,然后水解制得4,4′-联苯二甲酸;对氯代反应的历程进行了探讨,并通过正交实验考察了反应参数对4,4′-联苯二甲酸收率的影响,得到了优化工艺条件,优化工艺条件下的验证实验表明:反应总收率达到93.40%,纯度达99.20%。采用IR、~1HNMR对产物的结构进行表征,通过HPLC对生成的4,4′-联苯二甲酸的纯度进行测定。该合成工艺具有环境友好、工艺操作简单、转化率及收率高、经济性好等优点,适合工业化大规模生产。  相似文献   

9.
对碳酸二甲酯(DMC)与4,4′-二苯甲烷二胺(MDA)合成4,4′-二苯甲烷二氨基甲酸甲酯(MDC)的反应过程进行了研究,采用质谱、元素分析、红外光谱以及核磁共振氢谱等手段,对反应中间产物和最终产物进行了分离、组成结构分析和确认。研究结果表明,该反应是一个经过中间产物的串联反应,主产物为MDC,中间产物结构为4-(4′-氨苯基)苯甲烷氨基甲酸甲酯。  相似文献   

10.
利用变温核磁技术研究了杂多酸同芳磺酸的作用,提出了杂多酸催化芳烃磺化成砜的作用机理。  相似文献   

11.
新型层柱材料Zn2Al-SiW9M3的合成、表征及催化性能研究   总被引:1,自引:0,他引:1  
杂多阴离子柱撑粘土是一类新型层柱催化材料.本文采用水热合成与离子交换方法首次将三取代Keggin结构杂多阴离子α-[SiW9O37M3(H2O)3]n-(简写为SiW9M3,M=Mn2+,Cr3+,Ti3+,Fe3+)嵌入到Zn-Al型阴离子粘土层间,并通过XRD、IR、DTA和元素分析等手段对其结构进行了表征,考察了它们在顺丁烯二酸环氧化反应中的催化活性.  相似文献   

12.
甲苯二氨基甲酸甲酯(TDC),是碳酸酯法制备甲苯二异氰酸酯(TDI)的中间产物.碳酸二甲酯(DMC)代替光气与2,4-二氨基甲苯(TDA)反应合成TDC,TDC经催化或热分解制得TDI,这是一条没有污染物产生的绿色合成路线.……  相似文献   

13.
A laboratory study was carried out to investigate the secondary organic aerosol (SOA) products from photooxidation of the aromatic hydrocarbon toluene. The experiments were conducted by irradiating toluene/CH3ONO/NO/air mixtures in a home‐made smog chamber. The aerosol time‐of‐flight mass spectrometer (ATOFMS) was used to measure the size and the chemical composition of individual secondary organic aerosol particles in real‐time. According to a large number of single aerosol diameters and mass spectra, we obtained the size distribution and chemical composition of SOA statistically. Expeperimental results showed that aerosol created by toluene photooxidation is predominantly in the form of fine particles, which have diameters less than 2.5 μm (i.e. PM2.5), and the predominant components of aerosol are furane, methyl glyoxylic acid, phenol, benzaldehyde, benzyl alcohol, cresol, 3‐hydroxy‐2,4‐dioxo‐pentanal, methyl nitrophenol, and 5‐hydroxy‐4,6‐dioxo‐2‐heptenal. The possible reaction mechanisms leading to these products were also discussed.  相似文献   

14.
甲苯常压催化氧化制苯甲酸及其它芳烃的氧化反应的研究   总被引:2,自引:0,他引:2  
以25%甲苯无水乙酸作反应液,钴、锰和铵的混合盐作催化剂,乙腈作促进剂,纯氧为氧化剂,在110℃±2℃下,常压反应15h,苯甲酸收率达85%。用该催化剂体系氧化其它芳烃时,亦可获得类似结果。若芳烃侧链烷基R=C1~C6时,首先起反应的是与苯环相邻的碳原子,伯碳由醛变为酸;仲碳由酮升温后断链变酸;叔碳或烯键则直接断键变为酸。  相似文献   

15.
合成胶乳是合成橡胶的一个重要组成部分,而合成胶乳中丁苯胶乳又占主导地位。丁苯胶乳是由丁二烯(B)和苯乙烯(S)经过乳液聚合得到的一种固体含量为30%~50%的水性乳液。由于这种水性乳液具有橡胶的韧性,所以作为增强剂被广泛应用于造纸、涂料、纺织、建筑和粘合剂等各个领域,与人们的生活环境密切相关。对于胶乳性能的研究和改进也吸引了研究者的注意。但是生产原料如苯乙烯中普遍含有甲苯,所以造成胶乳产品含有痕量的甲苯,对人们健康形成潜在的威胁。  相似文献   

16.
A series of proton exchange membranes based on sulfonated polyarylene ether ketones(SPAEKs) was used to study the effect of sulfonation degree on proton conductivity, methanol permeation and performance of direct methanol fuel cells(DMFCs). Dependences of physical characteristics of the membranes, i. e., proton conductivity, water uptake, swelling ratio, methanol permeability and ion exchange capacity(IEC) were systematically studied. Both methanol permeability and proton conductivity of the SPAEK membrane grow rapidly as the increase in sulfonation degree since methanol molecules and protons share the same transfer channel. However,the methanol permeability plays more important role comparing to proton conductivity. As a result, the SPAEK membrane with a medium sulfonation degree(60%) was found to yield the best performance in a DMFC due to the acquirement of balanced conductivity and methanol permeability.  相似文献   

17.
Using the Hartree-Fock, MP2, and the B3LYP, BLYP, mPW1PW91 density functional methods, each combined with the 6-31G(d), 6-311G(d), 6-311+(d), 6-311++G(d, p) cc-pvdz and cc-pvtz basis sets, the equilibrium geometry of 4,4′ -bipyridine was optimized and the internal rotational potential barriers heights at 0° (AE0), 90° (AE90) were obtained. For the best basis set (cc-pvtz) , the predicted dihedral angle e ranges from 37.0 to 37.8° for all methods except the Hartree-Fock method (43.7). This agreed with the estimation from the electron diffraction experimental measurement (37.2°). The inter-ring C-C distance, ranging from 147.2 to 148.7 pm ( 147 pm experimental), is intermediate between the typical aromatic C-C bond and the aliphatic C-C bond. The results show that the inter-ring o-conjugation between two pyridyl rings stabilizes the co-planar conformer and the steric repulsion between the ortho neighboring hydrogens belonging to different rings favors the non-planar orthogonal conformer.  相似文献   

18.
Isatins react efficiently with 4-hydroxyproline in the presence of 10 mol% of PMA/SiO2 in acetonitrile/water (4:1) under reflux conditions to furnish N-substituted pyrroles in excellent yields. Similarly, 11H-indeno[1,2-b]quinoxalin-11-ones also participated in this reaction.  相似文献   

19.
锆钼杂多酸-耐尔蓝离子缔合显色反应的研究   总被引:2,自引:0,他引:2  
在聚乙烯醇(PVA)存在下,耐尔蓝(NB)与锆钼杂多酸(ZrMo)形成离子缔合物,其λ_(max)位于615nm,表观摩尔吸光系数e值为3.71×10~5L·mol~(-1)·cm~(-1),线性范围0~5μgzr/25ml。络合物至少稳定24h。考察了30多种共存离子的影响,允许25倍量铪存在。测定锆的适宜条件为[HClO_4]=0.9mol/L,[MoO_4~(2-)]=7.5×10~(-5)mol/L,[NB]=5.5×10~(-5)mol/L,PVA 0.08%。方法已用于岩矿中锆的测定,结果满意。用摩尔比法和平衡移动法测定缔合物的摩尔比为ZrMo:NB=1:4。探讨了反应机理。  相似文献   

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