Non‐Coordinated Phenolate Anions and Their Application in SF<sub>6</sub> Activation
Robin F. Weitkamp, Beate Neumann, Hans‐Georg Stammler, Berthold Hoge
Abstract
Abstract The reaction of the strong monophosphazene base with the weakly acidic phenol leads to the formation of a phenol–phenolate anion with a moderately strong hydrogen bond. Application of the more powerful tetraphosphazene base (Schwesinger base) renders the isolation of the corresponding salt with a free phenolate anion possible. This compound represents the first species featuring the free phenolate anion [H 5 C 6 ‐O] − . The deprotonation of phenol derivatives with tetraphosphazene bases represents a great way for the clean preparation of salts featuring free phenolate anions and in addition allows the selective syntheses of hydrogen bonded phenol‐phenolate salts. This work presents a phosphazenium phenolate salt with a redox potential of −0.72 V and its capability for the selective activation of the chemically inert greenhouse gas SF 6 . The performed two‐electron reduction of SF 6 leads to phosphazenium pentafluorosulfanide ([SF 5 ] − ) and fluoride salts.