Exploring the Bifunctional Nature of L ‐Proline for the Organocatalytic Synthesis of 2‐Amino‐1,3,4‐thiadiazoles and 2‐Amino‐1,3,4‐oxadiazoles Under Mild Reaction Conditions

We demonstrate a simple and efficient one‐pot synthesis of 2‐amino‐1,3,4‐thiadiazoles and 2‐amino‐1,3,4‐oxadiazoles by integrating benzothioamide with phenylformamide and using L ‐proline as a naturally occurring organocatalyst. A wide range of substrates was successfully synthesized with moderate to high yields (70%–92%) by using isopropanol as a green solvent under metal‐free ambient conditions. The mechanistic insights capitalize on the bifunctional nature of L ‐proline, enabling the formation of the iminium transition state and intermolecular hydrogen bonding.