Acetic Acid → 3-[[1-(carboxy)-3-phenyl-propyl]amino]-1-t-butoxycarbonylmethyl-2,3,4,5-tetrahydro-1H-benzazepin-2-one

Participants

Reaction Steps

Ethyl 3-benzoylacrylate (13a) (55.6 g, 272 mmoles) is dropped into a solution of (3S)-3-amino-1-t-butoxycarbonylmethyl-2,3,4,5-tetrahydro-1H-benzazepin-2-one (11) (66.2 g, 228 mmoles) in 200 ml of toluene, at room temperature in 1 h. The resulting mixture is left under stirring for 18 h, added with 10% Pd—C (26 g, 22 mmoles) and hydrogenated at 3 atm for 18 h at room temperature. After completion of the reaction, 200 ml of acetic acid are added and the mixture is hydrogenated for a further 18 h, at 3 atm at room temperature, after that the catalyst is filtered off through Celite and the solvent mixture is evaporated to dryness. The residue is taken up with isopropanol (500 ml) and the resulting precipitate is filtered, washed with 20 ml of dichloromethane and dried to give 3-[[1-(carboxy)-3-phenyl-propyl]amino]-1-t-butoxycarbonylmethyl-2,3,4,5-tetrahydro-1H-benzazepin-2-one (15) (58.5 g, yield: 52%).

Provenance & Evidence