Aerosol Direct Fluorination. Syntheses of the Perfluoroalkyl Orthocarbonates, F-Tetramethyl and F-Ethylene Orthocarbonates

摘要

The extension of aerosol direct fluorination techniques to the syntheses of perfluoroalkyl orthocarbonates from the analogue alkyl orthocarbonates is described. These perfluorinated compounds, F-tetramethyl orthocarbonate and F-ethylene orthocarbonate have not been previously prepared by any other method. They are stable, relatively unreactive and highly volatile. The orthocarbonates are acid sensitive and like ketals can be fluorinated without decomposition only under the low acidity conditions which prevail in the aerosol direct fluorination system. The unoptimized yields of F-tetramethyl orthocarbonate and F-trimethyl orthoformate the major products in the fluorination of tetramethyl orthocarbonate are 8% and 19.2% respectively, and make up 30% and 59% respectively of the total product collected. F-ethylene orthocarbonate fragments less and can be produced in 98% purity and a 17% theoretical yield based on the total amount of ethylene orthocarbonate injected. (Author)