Boric Acid → 2-Ethoxy-4-(3-((S)-3-methy-1-(2-piperidin-1-yl-phenyl)-butylamino)-2-oxo-propyl)-benzoic acid ethyl ester

Participants

Reaction Conditions

Reaction Steps

In a round bottom flask fitted with a dean stark condenser, (S)-3-methyl-1-(2-piperidinophenyl)-1-butylamine (10 g, 0.0406 mol) was dissolved in toluene (100 ml), followed by the addition of 3-ethoxy-4-ethoxycarbonyl phenyl acetic acid (10.26 g, 0.0407 mol) and boric acid (0.26 g, 0.0042 mol). The reaction mixture was refluxed for 16-18 hours. The resulting mass was then cooled to 25-30° C. followed by filtration. The filtrate was washed with water and 1.0% sodium bicarbonate solution followed by complete distillation of toluene and the resulting residue was stirred with hexane (50 ml) for 1 hour. The precipitated solid was filtered and washed with hexane (10 ml). The wet product was dried at 50-55° C. under vacuum for 4-6 hours to produce Ethyl (S)-2-ethoxy-4-[N-(1-(2-piperidino-phenyl)-3-methyl-1-butyl)-aminocarbonyl methyl]-benzoate (Yield=73.3%; HPLC Purity: 99.50%).

Provenance & Evidence