Oxalic acid dihydrate → Oxalic acid--3-{7-cyano-5-[(2R)-2-({2-[2-(2,2,2-trifluoroethoxy)phenoxy]ethyl}amino)propyl]-2,3-dihydro-1H-indol-1-yl}propyl benzoate (1/1)

Participants

Reaction Steps

Isopropyl alcohol (50 mL) and oxalic acid dihydrate (1.20 g) were added to 3-{7-cyano-5-[(2R)-2-({2-[2-(2,2,2-trifluoroethoxy)phenoxy]ethyl}amino)propyl]-2,3-dihydro-1H-indol-1-yl}propyl benzoate (6.40 g) which was obtained in the Example 1, and the mixture was dissolved by heating. After seeding of the title compound, the mixture was stood overnight. The precipitated crystals were collected by filtration and washed with a small amount of cooled isopropyl alcohol and dried under vacuum to give 3-{7-cyano-5-[(2R)-2-({2-[2-(2,2,2-trifluoroethoxy)phenoxy]ethyl}amino)propyl]-2,3-dihydro-1H-indol-1-yl}propyl benzoate mono oxalate (5.43 g). At this time, the content of by-product (C-a) in the obtained product was 0.9%.

Provenance & Evidence