PUB - Publikationen an der Universität Bielefeld

Weakly coordinating anions (WCAs) are of great academic as well as industrial interest. To advance the fluoroallcyl phosphate anion [P(C2F5)(3)F-3](-), which is ideally suited for technical applications, functional substituents X are attached to the Lewis acid (C2F5)(3)PF2. In keeping with this, the reaction of (C2F5)(3)PF2 with 4-(dimethylamino)pyridine (DMAP) yields the corresponding adduct [P(C2F5)(3)F-2(dmap)]. Treatment of this adduct with Bronsted acids (HX) leads to the selective formation of the corresponding phosphate anions [P(C2F5)(3)F2X](-) by trapping the proton with the liberated base DMAP. In this way, OH functions can be transformed in one step into WCAs, slightly increasing the coordination properties of the corresponding anion. An ion exchange to the corresponding [PPh4] salts results in solids, whereas the corresponding imidazolium salts are obtained as room-temperature ionic liquids.