The electrochemical fluorination of n-propyl-, diethyl- and triethylamine

Abstract

The electrochemical fluorination under many conditions of n-propyl-, diethyl- and triethylamine was studied. In the fluorination of these amines, many gaseous products such as CF 4, CHF 3, C 2F 6, C 3F 8 and NF 3 were formed, which resulted from the cleavage of carbon-carbon and carbon-nitrogen bonds. Increase in the concentration of the starting materials and of the cd caused increase of the total current efficiency of the gaseous products. In the fluorination of triethylamine, the maximum of the total current efficiency of the gaseous products was observed at 6° and −25°C for 2 and 10 mol-% solutions respectively. Furthermore, the molar ratio of CF 4 to C 2F 6 decreased with a rise of the temperature. These facts indicate that as the temperature becomes lower, the carbon-carbon bond is cleaved more violently, and that temperature has two opposite effects that accelerate and decelerate the cleavage of the carbon-nitrogen bond in triethylamine. Besides the gaseous products, a number of liquid products were formed. From the results of ir spectra, mass spectra and F 19 nmr they consisted of n-C 2F 10, (CF 3) 2C 2F 5N, (C 2F 5) 2CF 3N, (C 2F 5) 2C 2HF 4N, (C 2HF 4) 2C 2F 5N, (C 2F 5) 3N etc.