Developmental Research on Scale-up in Electrochemical Fluorination

电化学氟化放大研究进展本研究主要由两个项目组成。第一个是发展新的电化学全氟甲基化反应中的小囊状反应，第二个是放大电解的电化学三氟甲基化，在0。研究了丙烯酸甲酯、丙烯酰胺和丙烯腈的电化学全氟烷基化反应。全氟辛酸、丁酸和二氟乙酸以合理的产率提供了相应的全氟碳自由基的二聚体。在氧气气氛中，电解生成2-氧代或。2-羟基-4，4，4-三氟丁酯的产率为30-45%。这种氧代三氟甲基化反应有希望制备一些有价值的三氟甲基化合物，否则很难制备。当电流密度为50~80 mA/cm~2时，TFA和甲基丙烯酸甲酯的电解产率为50%。电解温度对电流效率有很大影响。为此目的，较低的温度在0摄氏度左右是可取的。

Developmental Research on Scale-up in Electrochemical FluorinationThis research consists of mainly two programs. The first is development of new electrochemical perfluoromethylation of olefins in a small sacle reactions and the second is a scale-up electrolysis of electrochemical trifluoromethylation, of methyl acrylate in 0. I kg scale by a flow cell electrolysis system.Electrochemical perfluoroalkylations of methyl acrylate, acrylamide, and acrylonitrile have been investigated. Perfluorooctanoic, butanoic, and difluoroacetic acids provided dimers of the corresponding perfluorinated carbon radicals in reasonable yields. In the oxygen atmosphere the electrolysis gave 2-oxo or. 2-hydroxy-4, 4, 4-trifluorobutylates in 30 - 45 % yields. This oxy-trifluoromethylation is promising for preparation of some valuable trifluoromethyl compounds otherwise difficult to prepare.A flow cell equipped with 10 X 10 cm^2 platinated titanium plates as electrodes was employed for 0. I Kg scale electrolysis of TFA and methylacrylate to give 50 % of the desired products at the current densities of 50 - 80 mA/cm^2. The temperature of the electrolysis affects current efficiency intensively. The lower temperature at around 0 C is desirable for the purpose.