On the Structure of [K(crypt‐222)]+.

Due to disorder, [K(crypt‐222)]+ CF 3 − (<bold>1</bold>) is crystallographically indistinguishable from its isomer, a 1:1 fluoroform clathrate of deprotonated [K(crypt‐222)]+, [K(crypt‐222{‐H+})]·CHF3 (<bold>2</bold>). In our preceding publications, <bold>1</bold> was characterized on the basis of combined X‐ray diffraction, NMR, reactivity, labeling, acid‐base, and DFT studies. Herein we report that neither incorporation of deuterium nor any other transformation of [K(crypt‐222)]+ is observed in the presence of CD3OD/CD3OK at 70 °C or CD3S(O)CD2K/(D6)DMSO at 23 °C over hours and even days. Since fluoroform is easily and quickly deprotonated under such conditions, the demonstrated greater acidity of CHF3 relative to [K(crypt‐222)]+ provides additional evidence in favor of <bold>1</bold> and against <bold>2</bold>. Likewise, crystal packing analysis and DFT calculations support <bold>1</bold>, which has now been refined in the ultimately correct space group <italic>R</italic>32. Our previously drawn conclusions regarding [K(crypt‐222)]+ CF 3 − and the existence of a ‘naked’ trifluoromethyl anion in a condensed phase remain valid. The recent alternative refinement (<italic>Becker and Müller</italic>,<italic> Chem. Eur. J</italic>. <bold>2017</bold>, 23, 7081 – 7086) of our raw diffraction data has been improperly performed in the wrong space group to yield a non‐charge‐balanced model [K(crypt‐222)]+·CHF3, which is hereby repudiated. <italic>Becker and Müller</italic>'s attempts to resolve the charge balance issue have produced models that are inadequate from the perspective of both crystallography and chemistry. [ABSTRACT FROM AUTHOR]