Synthesis, Properties, and Application of Tetrakis(pentafluoroethyl)gallate, [Ga(C 2 F 5 ) 4 ] −

Weakly coordinating anions (WCAs) are important for academic reasons as well as for technical applications. Tetrakis(pentafluoroethyl)gallate, [Ga(C 2 F 5 ) 4 ] − , a new WCA, is accessible by treatment of [GaCl 3 (dmap)] (dmap=4‐dimethylaminopyridine) with LiC 2 F 5 . The anion [Ga(C 2 F 5 ) 4 ] − proved to be reluctant towards deterioration by aqueous hydrochloric acid or lithium hydroxide. Various salts of [Ga(C 2 F 5 ) 4 ] − were synthesized with cations such as [PPh 4 ] + , [CPh 3 ] + , [(O 2 H 5 ) 2 (OH 2 ) 2 ] 2+ , and [Li(dec) 2 ] + (dec=diethyl carbonate). Thermolysis of [(O 2 H 5 ) 2 (OH 2 ) 2 ][Ga(C 2 F 5 ) 4 ] 2 gives rise to a dihydrate of tris(pentafluoroethyl)gallane, [Ga(C 2 F 5 ) 3 (OH 2 ) 2 ]. All products were characterized by NMR and IR spectroscopy, mass spectrometry, X‐ray diffraction, and elemental analysis. Furthermore, an outlook for the application of [Li(dec) 2 ][Ga(C 2 F 5 ) 4 ] as a conducting salt in lithium‐ion batteries is presented.