Chonnam National University researchers reported that dichloromethane and a basic salt can form amide bonds from carboxylic acids and alkyl amines using common lab chemicals.
The method emerged after a failed iridium-catalyzed decarboxylation unexpectedly produced chlorinated intermediates; follow-up tests showed the amide-forming reactivity came from DCM even without the metal catalyst.
A moderate range of starting materials worked, and the reaction usually preserved stereochemistry, though amino acids showed slight scrambling under basic conditions.
Limits remain: bulky amines react poorly, aromatic amines do not work, and DCM’s cancer-linked health risks have already driven tight US and EU regulation and industrial phaseouts.
Even so, the team says the protocol could offer a cheap, simple alternative to some amide-making routes that rely on costlier coupling reagents or generate toxic gases and heavy by-products.