Triethylamine → (3S,4S)-3-[3-(4-methanesulfonyl-benzyl)-2,4-dioxo-1,3,8-triaza-spiro[4.5]dec-8-ylmethyl]-4-phenyl-pyrrolidine-1-carboxylic acid tert-butyl ester

Participants

Reaction Steps

To 187 mg (0.50 mmol) of 3-(4-methanesulfonyl-benzyl)-1,3,8-triaza-spiro[4.5]decane-2,4-dione hydrochloride was added 5 mL of DCM followed by 0.066 mL of triethylamine (0.50 mmol) and a solution of (3R,4S)-3-formyl-4-phenyl-pyrrolidine-1-carboxylic acid tert-butyl ester (0.93 mL of a 148 mg/mL solution, 0.50 mmol). The solution was stirred at room temperature for 30 minutes and sodium triacetoxyborohydride was added (159 mg, 0.75 mmol). The solution was stirred overnight. The resulting mixture was evaporated to dryness and purified by chromatography on Bond Elute™ (10 g) using 1:1 EtOAc:Hexane followed by 1% methanol in DCM. After evaporation of the desired fractions, 93 mg (31%) of (3S,4S)-3-[3-(4-methanesulfonyl-benzyl)-2,4-dioxo-1,3,8-triaza-spiro[4.5]dec-8-ylmethyl]-4-phenyl-pyrrolidine-1-carboxylic acid tert-butyl ester as a white solid were obtained.

Provenance & Evidence