Benzocaine → Ethyl 2-Aminobenzothiazole-6-carboxylate

Participants

Reaction Steps

Ethyl 4-aminobenzoate (23.2 g, 140.4 mmol) and potassium thiocyanate (40.9 g, 420.9 mmol) were dissolved in acetic acid (280 ml), and under an ice cooling, bromine (22.4 g, 140.4 mmol) was slowly added thereto. The mixture was stirred under an ice cooling for 10 minutes and then stirred at a room temperature overnight. To the mixture, purified water was added and then ice was added. Thereafter, the resulting mixture was neutralized with ammonia water. The precipitate was separated by filtration, washed with purified water, and then subjected to through circulation drying to give the title compound (25.2 g, 81%) as a white powder.

Provenance & Evidence