Hydrochloric Acid → (3S)-1-amino-3-(4-bromophenyl)cyclopentane-1-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

To (7S)-7-(4-bromophenyl)-1,3-diazaspiro[4.4]nonane-2,4-dione (I-1B, 13.9 g, 45.0 mmol) in 1,4-dioxane (40 mL) in a round bottom flask was added aqueous NaOH (2N, 100 mL, 200 mmol). The mixture was heated to 95° C. and stirred for 24 hours. Additional NaOH (25 mL, 50 mmol) was added and heating continued for another two days. The solution was cooled with an ice-bath, neutralized with 5N HCl to approximately pH 7 resulting in the formation of a white precipitate. The solids were collected by filtration and dried under high vacuum for 2 days to provide 14 g of (3S)-1-amino-3-(4-bromophenyl)cyclopentanecarboxylic acid as a white solid which was used as such for the subsequent step without further purification. HPLC retention time=0.64 min (Condition G) LC/MS M+1=284/286.

Provenance & Evidence