我们最近开发了一种改进的合成路线,以合成1,1,2,2-四氟乙烷磺酸(HCF 2 CF 2 SO 3 H,TFESA),并探索了这种新获得的超强酸在催化中的应用。挥发性低,易于处理且方便11 H NMR处理使该酸成为三氟甲磺酸的有吸引力的替代物。TFESA也可以转化为几种衍生物:酸酐,磺酰氯和磺酰氟,它们为芳基磺酸盐的合成提供了良好的切入点。我们制备了1,1,2,2-四氟乙烷磺酸的几种芳基酯(芳基四氟甲磺酸),表明它们可用于许多钯催化的偶联反应(Suzuki,Heck和Buchwald-Hartwig偶联)。虽然四氟甲磺酸酯的反应性介于三氟甲磺酸酯和氯化物之间,但四氟甲磺酸酯似乎更热稳定。另外,四氟甲磺酸酯基团中氢原子的存在促进了反应的监测和衍生物的表征。
我们最近开发了一种改进的合成路线,以合成1,1,2,2-四氟乙烷磺酸(HCF 2 CF 2 SO 3 H,TFESA),并探索了这种新获得的超强酸在催化中的应用。挥发性低,易于处理且方便11 H NMR处理使该酸成为三氟甲磺酸的有吸引力的替代物。TFESA也可以转化为几种衍生物:酸酐,磺酰氯和磺酰氟,它们为芳基磺酸盐的合成提供了良好的切入点。我们制备了1,1,2,2-四氟乙烷磺酸的几种芳基酯(芳基四氟甲磺酸),表明它们可用于许多钯催化的偶联反应(Suzuki,Heck和Buchwald-Hartwig偶联)。虽然四氟甲磺酸酯的反应性介于三氟甲磺酸酯和氯化物之间,但四氟甲磺酸酯似乎更热稳定。另外,四氟甲磺酸酯基团中氢原子的存在促进了反应的监测和衍生物的表征。
A redox-initiated per(poly)fluoroalkylation of olefins by per(poly)fluoroalkyl chlorides
作者:Changming Hu、Fengling Qing
DOI:10.1021/jo00022a025
日期:1991.10
The per(poly)fluoroalkylation of olefins by per(poly)fluoroalkyl chlorides, initiated by ammonium persulfate/sodium formate (NH4)2S2O8/HCO2Na), is described. The reaction proceeds smoothly in polar aprotic solvents. The presence of functional groups like sodium carboxylate or sulfonate in the polyfluoroalkyl chloride appear to facilitate the reaction. The reaction appears to be initiated by a single-electron transfer, represents the first example of the reactivity of per(poly)fluoroalkyl chlorides, and also demonstrates their use as per(poly)fluoroalkylating agents. For alpha-chloro-omega-iodoperfluoroalkanes only the carbon-iodine bond is cleaved during the reaction. An explanation for the apparent stability of the carbon-chlorine bond in such compounds is given.