What is "diaziridine"

n. (context organic compound English) A saturated, three-membered heterocycle containing one carbon atom and two nitrogen atoms

Diaziridines are heterocyclic compounds containing two nitrogen atoms in a three-membered ring. They can be considered as strained hydrazines. Due to the ring strain, the nitrogen atoms are configuration stable leading to cis-trans isomers. They are usually synthesized by a method developed by E. Schmitz: A carbonyl compound is treated with ammonia or respectively a primary aliphatic amine and an aminating reagent like hydroxylamine-O-sulfonic acid (HOSA) under slightly basic conditions. The final step is based on the intramolecular cyclization of an aminal.