共查询到18条相似文献,搜索用时 281 毫秒
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硫酸氢钠催化合成羧酸环已酯 总被引:1,自引:0,他引:1
硫酸氢钠能够代替硫酸作为酯化作用的催化剂。研究了一水硫酸氢钠催化丙酸环已酯的反应条件。当mol羧酸:mol环已醇:mol硫酸氢钠=2.3:0.07,以环已烷为溶剂,合成了甲酸环已酯,乙酸环已酯、丙酸环已酯和丁酸环已酯,疏经为77.9%-89.0%。 相似文献
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梨圆蚧是对果林危害较大的害虫。该虫的性信息素包括三个组分:3-亚甲基-7-甲基-7-辛烯-1-醇丙酸酯(1)、(2Z)-3,7-二甲基-2,7-辛二烯-1-醇丙酸酯(2)和(2E)-3,7-二甲基-2,7-辛二烯-1-醇丙酸酯(3)。本文介绍了通过对月桂烯进行结构改造来合成梨圆蚧性信息素,从月桂烯到1,总产率为19%。工业上从月桂烯制龋萑花醇和香叶醇,再将橙花醇和香叶醇转变为相应的氯烯醇后再还原、丙酰化即得2和3,其总产率分别为30%和28%。(以橙花醇和香叶醇计)。月桂烯可从β-蒎烯裂解而得。我国有丰富的蒎烯资源,所以开辟从月桂烯合成梨圆蚧性信息素的新途径具有重要的意义。 相似文献
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以三氟丙烯和溴为原料加成制得1,2-二溴三氟丙烷,脱溴化氢得到2-溴三氟丙烯,再在一定条件下合成2-溴三氟丙烯的格氏试剂(三氟异丙烯基溴化镁),与CO2反应最终生成1-溴-2-三氟甲基丙酸。 用碳酸钠溶液萃取的方法得到0.8 g产品,纯度为99.6%,收率为3.6%。 对产物进行了MS、IR、1H NMR和13C NMR等表征,并分析了主要副产物1,2-二氟丙二烯和2,3-二三氟甲基-1,3-丁二烯及其与未反应的2-溴三氟丙烯间的[2+2]或[2+4]环加成反应产物。 确定以2-溴三氟丙烯为原料经格氏反应制羧酸较好的反应条件为:以THF为溶剂,1,2-二溴乙烷作引发剂,制备格氏试剂温度为30 ℃,CO2与格氏试剂反应温度为0 ℃。 相似文献
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分子筛催化羧酸与环氧化合物的加成反应 总被引:1,自引:0,他引:1
羧酸与环氧化合物的开环加成反应,由于原料易得,产物羧酸β-羟基丙酯在医药、涂料、胶粘剂以及合成纤维中有广泛应用,因此对这类反应的研究一直受到人们的重视。已见报道的反应催化剂有叔胺、季铵盐、无机碱、金属有机羧酸配合物或高分子配合物。 本文用离子交换法将HZSM-5改性为Fe-ZSM-5、Cu-ZSM-5、Co-ZSM-5、Ni-ZSM-5。以丙酸 相似文献
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双官能团修饰的新型有机锗倍半氧化物的合成 总被引:1,自引:0,他引:1
通过锗氯仿和3-烷氧羰基丙烯-2-磷酸二烷酯的反就,合成了β位置磷酰基团和羰基同时修饰的有机锗倍半氧化物,对合成方法作了一定的探讨。所有产物的结构均经过^1HNMR、^31P NMR、IR和元素分析等方法证明。 相似文献
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2-三氟甲基-3-氧杂-八氟己酸烯丙酯或2,5-二(三氟甲基)-3,6-二氧杂-十二氟壬酸烯丙酯可在钯的作用下产生相应的全氟碳负离子. 这些碳负离子能够质子化或者对取代苯甲酰氯发生亲核进攻, 后者为芳基氟烷基酮的合成提供了一条简捷途径. 另一方面,上述含氟酸的甲酯和取代苯甲酰氯在钯的作用下同样能发生反应而生成相应的芳基氟烷基酮. 相似文献
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Wang Y. Zhang J. Hou Y. Ruan G. Pan M. Liu T. 《Journal of Thermal Analysis and Calorimetry》2003,73(3):923-929
The polymerization kinetics of DL- and L-aspartic acid, either in the absence or presence of sodium bisulfate were studied with thermogravimetric analysis. The results
revealed that the polymerization of both types of aspartic acids proceeds through the dehydration in two steps, the loss of
one water molecule in each step, and the presence of sodium bisulfate effectively catalyzed the polymerization.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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Tao Gan Yanjuan Zhang Yang Su Huayu Hu Aimin Huang Zuqiang Huang Dong Chen Mei Yang Juan Wu 《Cellulose (London, England)》2017,24(12):5371-5387
The present study focused on investigating the catalytic mechanism of metal salts (sodium hypophosphite, sodium bisulfate and ammonium ferric sulfate) for esterification of bagasse cellulose carried out by mechanical activation-assisted solid phase reaction in a stirring ball mill. FTIR analysis of the products confirmed that these metal salts could catalyze the esterification of cellulose. XRD, SEM, FTIR, and 31P-NMR analyses of different samples indicated a synergistic effect between metal salt and ball milling, and the presence of metal salts enhanced the destruction on crystal structure of cellulose by mechanical force. The catalytic mechanism of three metal salts was difference: sodium bisulfate and ammonium ferric sulfate belonged to the catalytic mechanism of protonic acid and Lewis acid, respectively, while the catalytic mechanism of sodium hypophosphite was considered as that it could react with maleic acid to form active intermediates under ball milling. 相似文献
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D. V. Orekhov O. A. Kazantsev A. P. Sivokhin T. A. Khokhlova 《Russian Journal of Applied Chemistry》2014,87(7):881-886
Micellar catalysis with various polyoxyethylated compounds was used to synthesize sodium allyl sulfonate by the reaction of allyl chloride with an aqueous solution of sodium sulfite. It was shown that methoxy polyethylene glycol methacrylates and water soluble polymers based on these compounds are surfactants and can be used to intensify the synthesis of sodium allyl sulfonate, which is of interest in the case of its subsequent application to obtain copolymers with methoxy polyethylene glycol methacrylates. 相似文献
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3,7-Dinitrodibenzobromonium bisulfate 3 was prepared directly by the reaction of4,4' -dinitrobiphenyl with sodium bromide and potassium persulfate in the concentrated sulphuric acid. Metathetical reactions of 3 gave 3, T-dinitrodibenzobromonium chloride 4, bromide 5 and iodide 6, respectively. Crystal structure of 3a obtained by crystallization of 3 in formic acid showed that each molecule of 3a consists of two dibenzobromonium ions, two bisulfate anions and a formic acid. The dibenzobromonium ion is nearly coplanar. Compound 3 can dramatically increase mice's immunofunction. 相似文献