NEW POLYFLUOROALKOXYSULFONYL FLUORIDES .4. AROMATIC DERIVATIVES

The reactions of CF2CF2OSO2 and CF3CFCF2OSO2 with aromatic haloalkanes (RX, X Br) in the presence of silver fluoride were studied as a means for preparing novel aromatic polyfluoroalkoxysulfonyl fluorides. The following compounds have been prepared and characterized: ROCF2CF2SO2F and ROCF2CF(CF3)SO2F, where R is C6H5CH2, o-(CF3)2C6H3CH2, C6F5CH2. Infrared, mass and nmr spectra are presented in order to support the assigned structure. In a comparative study, the reaction of CFHCF2OSO2 with benzyl bromide, in the presence of different metal fluorides such as silver fluoride, cesium fluoride and tris(dimethylamino)sulfonium difluorotrimethylsilicate were investigated. In all cases decomposition products such as SO2F2, SOF2 and SO2 were obtained; no desired alkoxy product was found. Attempts to prepare the silver alkoxide salt, AgOCF2CFHSO2F or the corresponding aromatic alkoxy derivatives were unsuccessful. Apparently the intermediate silver salt is unstable and cannot be recovered or used for nucleophilic displacement reactions. © 1990.