Amidines have been reported to react with CO2 to form astable and isolable zwitterionic adduct but previous studieswere performed in the presence of at least some water.However, spectroscopy of the reaction between DBU and CO2detects the rapid formation of the bicarbonate salt of DBUwhen wet DBU is exposed to CO2 and does not indicate thatan isolable zwitterionic adduct between DBU and CO2 formseither in the presence or the absence of water.
