Comment on “Crystallographic Snapshot of an Arrested Intermediate in the Biomimetic Activation of CO 2 ”

Out of focus : A recent Communication published in this journal describes the synthesis of [ n Bu 4 N]HCO 3 . The authors performed a single‐crystal X‐ray study that revealed a putative species described as an incipient hydroxide ion engaging in a long, and presumably weak, interaction with CO 2 . Our recent exploration of the coordination chemistry of CO 2 with small ions leads us to believe that such an exceptional bonding situation is unlikely. Instead, we argue that the crystal structure is that of [ n Bu 4 N]O 2 CCH 3 and therefore not representative of the bulk powder from the synthesis.