Dronedarone Hydrochloride → 2-Butylbenzofuran-5-amine

Participants

Reaction Steps

This method is very simple and economical as regards the number of the reaction steps. Its drawback is, however, that in the last step the hydrochloride salt of dronedarone is obtained in a rather contaminated form. This can be explained by the presence of the dibutylamino-propyl group in the Friedel-Crafts reaction. In the examples of WO02/48132 the yield is 90%, during the purification steps at first the raw dronedarone hydrochloride salt, then following treatment with hydrogen chloride solution in isopropanol, the purified dronedarone hydrochloride salt is obtained (90%). It means that the yield of the raw dronedarone hydrochloride is 90% and then the purification step has a yield of 90%. Another drawback of the method is that the reactants used in the Friedel-Crafts reaction and the obtained by-products are insoluble in water, thus they cannot be removed from the system by aqueous washing.

Provenance & Evidence