Fluorinated tetraphenylborate anion

The fluorinated tetraphenylborates are a group of related anions, chemical compounds with a negative electrical charge. They are weakly coordinating anions, meaning they are very resistant to most chemical reactions, and can be used to study very reactive cations (positive ions) that can't form solid salts with more reactive anions.^[1] Fluorinated tetraphenylborates were discovered by a team led by Japanese chemist Hiroshi Kobayashi in 1981.^[2]

Fluorinated tetraphenylborates are given the shorthand chemical formula [BAr^F₄]⁻, and nicknamed "BARF". This is not a proper molecular formula: Ar^F just means "some aromatic group with some fluorines", without being more specific. Specific ions are also given shorthand names, usually including the number of fluorine atoms as a way to tell them apart.

Two important fluorinated tetraphenylborate anions are [BArF₂₄]⁻ (real formula [B((CF₃)₂C₆H₃)₄]⁻, systematic name tetrakis[3,5-bis(trifluoromethyl)phenyl]borate) and [BArF₂₀]⁻ (real formula [B(C₆F₅)₄]⁻, systematic name tetrakis(pentafluorophenyl)borate).^[3]

References

↑ Beil, Sebastian B.; Möhle, Sabine; Enders, Patrick; Waldvogel, Siegfried R. (2018). "Electrochemical instability of highly fluorinated tetraphenyl borates and syntheses of their respective biphenyls". Chemical Communications. 54 (48): 6128–6131. doi:10.1039/C8CC02996B. PMID 29808852.
↑ Yakelis, Neal A.; Bergman, Robert G. (2005). "Safe Preparation and Purification of Sodium Tetrakis[(3,5-trifluoromethyl)phenyl]borate (NaBArF₂₄): Reliable and Sensitive Analysis of Water in Solutions of Fluorinated Tetraarylborates". Organometallics. 24 (14): 3579–3581. doi:10.1021/om0501428. PMC 2600718. PMID 19079785.
↑ Wrede, Michael; Ganza, Viktoria; Kannenberg, Geraldt; Rominger, Frank; Straub, Bernd F. (2011). "Synthesis, structure, and unprecedented solubility of lipophilic borate salts". Inorganica Chimica Acta. 369: 71–75. doi:10.1016/j.ica.2010.12.039.

[1] Beil, Sebastian B.; Möhle, Sabine; Enders, Patrick; Waldvogel, Siegfried R. (2018). "Electrochemical instability of highly fluorinated tetraphenyl borates and syntheses of their respective biphenyls". Chemical Communications. 54 (48): 6128–6131. doi:10.1039/C8CC02996B. PMID 29808852.

[2] Yakelis, Neal A.; Bergman, Robert G. (2005). "Safe Preparation and Purification of Sodium Tetrakis[(3,5-trifluoromethyl)phenyl]borate (NaBArF₂₄): Reliable and Sensitive Analysis of Water in Solutions of Fluorinated Tetraarylborates". Organometallics. 24 (14): 3579–3581. doi:10.1021/om0501428. PMC 2600718. PMID 19079785.

[3] Wrede, Michael; Ganza, Viktoria; Kannenberg, Geraldt; Rominger, Frank; Straub, Bernd F. (2011). "Synthesis, structure, and unprecedented solubility of lipophilic borate salts". Inorganica Chimica Acta. 369: 71–75. doi:10.1016/j.ica.2010.12.039.

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