Asinger reaction

[2] An α-halogenated carbonyl-component reacts with sodium hydrosulfide (NaSH) and forms a Thiol in situ.

The thiol reacts directly with another carbonyl component and ammonia to form a thiazoline.

The reaction works also by using elemental sulphur, an α–substituted ketone, another carbonyl component and ammonia; in this case, a mixture of products is formed.

An α-halogenated carbonyl compound reacts with sodium hydrosulfide (NaSH) and forms a thiol in situ which reacts directly with aldehydes or ketones and ammonia to 3-thiazolines.

[4] The chemical industry developed based on the Asinger-reaction multi stage processes for the production of pharmaceuticals like D-penicillamine[5] and the aminoacid DL-cysteine.