摘要
制备了全氟辛基磺酸镱(Yb(OSO2C8F17)3)催化剂,研究了该催化剂作用下以全氟萘烷(C10F18)为氟溶剂对芳烃进行氟两相硝化。含有催化剂的氟相通过简单的相分离,就可回收利用。反应具有强对位选择硝化能力,乙苯、溴苯和碘苯的对位硝化比例分别提高18%、15%和16%。测定了不同温度下氟化物在有机相中的溶解度。考察了反应温度、氟相和有机相的体积比与体系中的含水量对氟两相硝化区域选择性的影响。发现甲苯、乙苯、氟苯、氯苯、溴苯、碘苯和二苯醚的最佳氟两相选择性硝化温度分别为80℃、60℃、60℃、60℃、80℃8、0℃和70℃,当加入25%的水时,催化剂已基本失去活性,在氟相和有机相能完全互溶的体系中升高氟相和有机相的体积比有利于降低邻对位比值。
The catalyst of Ytterbium（Ⅲ） perfluorooctanesulfonate （Yb（OSO2C8F17）3） is prepared and the nitration of aromatics on Yb（OSO2C8F17）3 catalyst with fluorous biphasic system is investigated. Perfluorodecalin （C10F18） was used as a fluorous solvent for this reaction. By simple separation of the fluorous phase containing only catalyst, the nitration was repeated many times. The para-selectivities of mononitration in aromatic compounds such as ethylbenzene, bromobenzene and iodobenzene increased by 18 %, 15 % and 16 % respectively. The solubilities of the fluorous compounds in organic solvents under different temperature were measured. The effects of the reaction temperature, the ratio of fluorous phase and organic phase and the water in the reaction system on the nitration were investigated. It was observed that the optimum temperature for the fluorous biphasic regioselective nitrations of toluene, ethylbenzene, flurobenzene, chlorobenzene, bromobenzene, odobenzene and diphenyl ether were 80℃, 60℃, 60℃, 60℃, 80℃, 80℃ and 70℃ respectively. The catalyst had almost no activity when the reaction system contained 25 % （volume ratio） of water. Simultaneously, increasing the volume ratio of fluorous phase and organic phase in the system in which the fluorous phase can miscible with organic phase could decrease ortho-para ratio.
出处
《南京理工大学学报》
EI
CAS
CSCD
北大核心
2006年第1期97-101,共5页
Journal of Nanjing University of Science and Technology
基金
国防科工委"十五"预研项目
关键词
氟两相硝化
全氟萘烷
全氟辛基磺酸镱
芳烃
选择性硝化
nitration with fluomus biphasic system
perfluorodecalin
Ytterbium （Ⅲ） perfluorooctanesulfonate
aromatics
regioselective nitration
