Hydrogen Bromide → 2,6-Diamino-4,5,6,7-tetrahydrobenzothiazole

Participants

Reaction Conditions

Reaction Steps

Bromine (112 g) was added dropwise to a solution of 4-acetamidocyclohexanone (100 g) in 500 ml water at room temperature. The mixture was warmed to approximately 45° C. and maintained at this temperature until the bromine colour had been lost. To this, thiourea (125 g) was added, and the mixture was heated to approximately 80° C. To this, aqueous hydrobromic acid (100 ml) was added, and the contents of the reaction vessel were refluxed. The contents were then cooled to approximately 10° C., and neutralized with caustic lye solution. The product, 2,6-diamino-4,5,6,7-tetrahydro-benzthiazole, was isolated by filtration, and washed with chilled water and dried. The product was off-white in colour, and the yield was approximately 60 g in weight.

Provenance & Evidence