text: A revolution in this area occurred in the 1990s with the introduction of the [[Tetrakis(3,5-bis(trifluoromethyl)phenyl)borate|tetrakis[3,5-bis(trifluoromethyl)phenyl]borate]] ion, , commonly abbreviated as  and colloquially called "BARF". This anion is far less coordinating than tetrafluoroborate, hexafluorophosphate, and perchlorate, and consequently has enabled the study of still more electrophilic cations. Related tetrahedral anions include tetrakis(pentafluorophenyl)borate , and .
  In the bulky borates and aluminates, the negative charge is symmetrically distributed over many electronegative atoms. Related anions are derived from tris(pentafluorophenyl)boron B(CF).  Another advantage of these anions is that their salts are more soluble in non-polar organic solvents such as dichloromethane, toluene, and, in some cases, even alkanes.  Polar solvents, such as acetonitrile, THF, and water, tend to bind to electrophilic centers, in which cases, the use of a non-coordinating anion is pointless.
  Salts of the anion  were first reported by Kobayashi and co-workers.  For that reason, it is sometimes referred to as Kobayashis anion. Kobayashis method of preparation has been superseded by a safer route.
  The neutral molecules that represent the parents to the non-coordinating anions are strong Lewis acids, e.g. boron trifluoride, BF and phosphorus pentafluoride, PF.  A notable Lewis acid of this genre is tris(pentafluorophenyl)borane, B(CF), which abstracts alkyl ligands:
  :(CH)Zr(CH) + B(CF) → [(CH)Zr(CH)][(CH)B(CF)]