Pyridine → N-[1-(S)-Ethoxycarbonyl-3-phenylpropyl]-L-alanine-N-carboxyanhydride

Participants

Reaction Steps

Disodium dihydrogen phosphate dihydrate (177 gms; 0.994 moles) was dissolved in water (300 ml) at 35° C. and cooled to ambient temperature. Dichloromethane (250 ml) was charged and stirred for 15 mins. N-[1-(S)-ethoxy carbonyl-3-phenyl propyl]-L-alanine (106 gms; 0.381 moles) was added to the above solution and the reaction mass was cooled to 15° C. Solution of triphosgene (52.8 gms; 0.177 moles) dissolved dichloromethane (40 ml) was added dropwise to the reaction mass in 40 mins at 15-20° C. The reaction mass was further stirred for 30 min. Pyridine (0.5 ml; 0.006 moles) was added and the reaction mass was stirred for 1 hr at 15-20° C. The reaction mass was settled and layers were separated. Organic layer was washed with 2N HCl till the neutral pH obtained. The organic layer was further washed with water and dried over sodium sulphate. The solvent was evaporated to residue (110 gms).

Provenance & Evidence