SYNTHESES AND LIPOPHILICITIES OF TETRAARYLBORATE IONS SUBSTITUTED WITH MANY TRIFLUOROMETHYL GROUPS

Syntheses were investigated using various tetraarylborate ions with a large number of trifluoromethyl groups: tetrakis[3,5-bis(trifluoromethyl)phenyl]borate; tetrakis [3,5-bis(1-methoxy-2,2,2-trifluoro-1-(trifluoromethyl)ethyl)phenyl]borate; tetrakis[3-(1-methoxy-2,2-trifluoro-1-(trifluoromethyl)ethyl)-5-(trifluoromethyl) phenyl] borate; and tetrakis[3-(2,2,2-trifluoro-1-(2,2,2-trifluoroethyoxy)-1-(trifluoromethyl)ethyl)-5-(trifluoromethyl)phenyl]borate ions. The preparation of Grignard reagents and the subsequent reaction with boron trifluoride etherate are important steps for a higher yield and easier isolation of the product. Sodium- and tetramethylammonium salts of these borate ions are soluble in halocarbon solvents such as dichloromethane, chloroform and 1,2-dibromotetrafluoroethane.