Oxalic Acid → (1R,2S,3R,5R,6R)-2-amino-2-cyano-3-[(3,4-dichloro benzyl)oxy]-6-fluoro bicyclo[3.1.0]hexane-6-carboxamide oxalate

Participants

Reaction Steps

To ethyl acetate (5 mL) solution containing 251.0 mg of the mixture of (1R,2S,3R,5R,6R)-2-amino-2-cyano-3-[(3,4-dichloro benzyl)oxy]-6-fluoro bicyclo[3.1.0]hexane-6-carboxamide (6a) and (1R,2R,3R,5R,6R)-2-amino-2-cyano-3-[(3,4-dichloro benzyl)oxy]-6-fluoro bicyclo[3.1.0]hexane-6-carboxamide (8a) [containing (6a): 171.5 mg and (8a): 75.1 mg], 67.7 mg (content: 98 wt %) of oxalic acid was added and stirred for 17 hrs and 50 min at room temperature. The resulting slurry was filtered under suction, washed with 2 mL of ethyl acetate, and dried under reduced pressure at room temperature. 217.0 mg of the resulting colorless powder (229.1 mg obtained) was suspended in 2.5 mL of ethyl acetate, and stirred at room temperature for 15.5 hrs. The resulting slurry was filtered under suction, washed with 2 mL of ethyl acetate, and dried under reduced pressure at room temperature to obtain 193.5 mg of (1R,2S,3R,5R,6R)-2-amino-2-cyano-3-[(3,4-dichloro benzyl)oxy]-6-fluorobicyclo[3.1.0]hexane-6-carboxamide oxalate (6d) as a colorless solid.

Provenance & Evidence