Sodium Hydroxide → 3-Aminoazepan-2-one hydrochloride

Participants

Reaction Steps

A stirred mixture of L-lysine hydrochloride 1 (55 g, 300 mmol) and NaOH (12 g, 300 mmol) in hexanol (1.2 L) is heated to reflux with a Dean-Stark trap used to remove H2O. The suspension is refluxed for 8 hours until all starting material is consumed (which maybe determined by 1 H NMR). The suspension is then cooled and filtered to remove byproduct NaCl. The filtrate is concentrated and the resulting crude α-amino-ε-caprolactam 2 is dissolved in water. After acidification to pH 6 with addition of concentrated HCl and partial concentration, crystals maybe formed at room temperature to afford α-amino-εcaprolactam hydrochloride (37 g) in 75% yield.

Provenance & Evidence