1. Lek Pharmaceuticals d. d., Sandoz Development Center Slovenia, API Development, Kolodvorska 27, 1234 Menge?, Slovenia;2. Lek Pharmaceuticals d. d., Sandoz Development Center Slovenia, Verov?kova 57, 1526 Ljubljana, Slovenia
Abstract:
A two-step process to synthesize racemic lorcaserin was developed from 2-(4-chlorophenyl)ethanol via formation of bromide or tosylate derivatives. These derivatives were reacted with allylamine in neat conditions to provide pure N-(4-chlorophenethyl)allylammonium chloride. This compound was cyclized in neat conditions using aluminum or zinc chloride to give racemic lorcaserin. After resolution of enantiomers, the wrong enantiomer was racemized and recycled to give new R-lorcaserin.