Organocatalytic Deuteration Induced by the Dynamic Covalent Interaction of Imidazolium Cations with Ketones

In this article, we suggest a new organocatalytic approach based on the dynamic covalent interaction of imidazolium cations with ketones. A reaction of N‐alkyl imidazolium salts with acetone‐d6 in the presence of oxygenated bases generates a dynamic organocatalytic system with a mixture of protonated carbene/ketone adducts acting as H/D exchange catalysts. The developed methodology of the pH‐dependent deuteration showed high selectivity of labeling and good chiral functional group tolerance. Here we report a unique methodology for efficient metal‐free deuteration, which enables labeling of various types of α‐acidic compounds without trace metal contamination.