Hydrochloric Acid → Trandolapril

Participants

Reaction Steps

(2S,3aR,7aS) octahydro-1H-indole-2-carboxylic acid (65 gms 0.384 moles) was stirred in dichloromethane (200 ml), triethyl amine (30 ml) was added under stirring at ambient temperature for 30 mins. N-[1-(S)-ethoxy carbonyl-3-phenyl propyl]-L-alanine N-carboxy anhydride (110 gms; 0.378 moles) (residue from Step A) dissolved in dichloromethane (50 ml) was added dropwise to the reaction mass at ambient temperature and further stirred for 3 hrs. Water (500 ml) was added and the reaction mass was cooled to 15° C., pH of the reaction mass was adjusted to 4.2 using 2N HCl. The organic layer was separated and aqueous layer reextracted with dichloromethane. The combined organic layer was dried with sodium sulphate and concentrated to residue. The residue was dissolved in ethylacetate at reflux temperature. The reaction mass was cooled to ambient temperature. The resulting solid was filtered and dried under vacuum to get 50 gms of Trandolapril (HPLC purity 99.5%)

Provenance & Evidence