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在脱水剂PCl3的存在下,噻吩-2,5-二甲酸与乙醇胺反应直接生成噻吩-2,5-双噁唑啉及未环化产物1和2。副产物1和2碱性关环生成噻吩-2,5-双噁唑啉,总收率达63%。此方法的优点是合成路线短,操作简单。 相似文献
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本文综述了近年来固载手性双噁唑啉的合成及其金属配合物作为手性催化剂在催化不对称反应中的研究进展。 相似文献
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以芳香酸为原料,通过酯化、肼解制得芳基甲酰肼,芳基甲酰肼再与芳香醛反应得到相应的酰腙,最后酰腙与三氟乙酸酐反应脱水环化成标题化合物,并利用IR、1HNMR、13CNMR、ESI-MS和元素分析对8个目标化合物的结构进行了表征.用MTT方法评价了它们在体外对HepG-2,A549-1和231-2 3种癌细胞株的体外生长抑制活性.结果表明,所合成的8个新化合物均具有潜在的体外抑制癌细胞生长活性,其中3-N-三氟乙酰基-2-(4-溴苯基)-5-(4-氟苯基)-1,3,4-(口恶)唑啉、3-N-三氟乙酰基-2-(4-氯苯基)-5-(4-氟苯基)-1,3,4-(口恶)唑啉活性最强. 相似文献
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4-甲氧基苯甲酰肼(1)与芳醛反应得到相应的酰腙(2a~2j),2a~2j分别与丙酸酐脱水环化成了3-N-丙酰基-1,3,4-(口恶)唑啉类化合物(3a~3j),通过元素分析、IR、1HNMR和MS对化合物3a~3j的结构进行了表征. 相似文献
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Two different bisoxazolines, 2,2′‐(1,3‐phenylene) bis(2‐oxazoline) (1,3‐PBO) and 2,2′‐bis(2‐oxazoline) (BO) were investigated as chain extenders for short chain unsaturated polyesters (UPEs). These extenders reacted readily with carboxyl ends of unsaturated polyesters, leading to rapid molecular weight increase through coupling of oligomeric chains. Commercially available unsaturated polyesters commonly have molecular weights around 1500, usually reached after a 20‐h polyesterification reaction. When bisoxazolines were reacted with short UPE chains obtained at the 6th hour of a commercial polyesterification reaction, the molecular weight of UPE reached 1500 within 5–30 min, which provides economies and prevents the glycol loss and yellowing which are associated with extended reaction times. Styrene solubility, gel time, and thermal and mechanical properties of the chain extended polyesters remained comparable to the commercial UPE, with 8–10 min of gel time and a storage modulus about 3000 MPa. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
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双(2-氯乙基)醚的合成新方法 总被引:1,自引:1,他引:0
作为冠醚合成的基本原料多甘醇二卤化物,在合成上,均是依照Pedersen C J在1967年及1972年时所提出的方法[1~3],该方法是将相应的多甘醇与氯化亚硫酰在苯中吡啶存在下反应.这个方法适用于二甘醇二氯化物(即双(2-氯乙基)醚,简称二氯乙醚)合成,产率一般较高,但反应进行得很缓慢,操作环境毒性很大,目标产品的分离提纯程序较多.本文提出一种新的合成双(2-氯乙基)醚的方法,使反应时间大大缩短;避免了在毒性很大的环境下操作;反应完全以后的分离提纯简单,目标产品可以直接从反应混合物中减压蒸馏得到;降低了产品的生产成本. 相似文献
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A C3-symmetric terbium complex {[Tb2(pztc)3]?6.5H2O}n (1) (pztc = pyrazine-2,3,5,6-tetracarboxylate), with hexagonal cavities, has been synthesized under hydrothermal conditions and characterized by X-ray single-crystal diffraction, elemental analysis, IR, TGA, PXRD and fluorescence measurements. The layer structure of the 2D complex is just like the structure of graphite. The most appealing structure is that a hexagonal C3-symmetric (H2O)7 guest fits into the hexagonal C3-symmetric terbium complex cavity very fitly. Furthermore, when the water clusters are driven off, the framework does not collapse and the luminescence intensity increases. 相似文献
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Procedures were developed for the large-scale synthesis of bis(2-hydroxyethyl) selenide and bis(2-aminoethyl) selenide. These bifunctional selenides were converted into a series of polyesters, polyureas, and polyurethanes. Methods of syntheses and properties of these condensation polymers are described. 相似文献