1,1'-Carbonyldiimidazole → HCID 57945182, compound

Participants

Reaction Steps

To a solution of (1R,2S)-1-(tert-butoxycarbonylamino)-2-(2,2-difluoroethyl)cyclopropanecarboxylic acid (665 mg, 2.507 mmol) in THF (20 mL) was added CDI (528 mg, 3.26 mmol) and the formed solution was stirred at rt for 3 h. Cyclopropanesulfonamide (395 mg, 3.26 mmol) and DBU (0.756 mL, 5.01 mmol) were added and the mixture was stirred at rt overnight. The reaction was diluted with EtOAc and washed with 1.0M HCl solution. The aqueous layer was extracted with EtOAc and the combined organics were washed with 5% citric acid, brine, dried over MgSO4, filtered and evaporated to give crude material. The crude product was purified on the Biotage (acetone/hexanes 5-30%) to give the pure product tert-butyl (1R,2S)-1-(cyclopropylsulfonylcarbamoyl)-2-(2,2-difluoroethyl)cyclopropylcarbamate (783 mg, 1.913 mmol, 76% yield) as a white solid. 1H NMR (500 MHz, MeOD) δ 1.01-1.15 (m, 2H), 1.16-1.35 (m, 2H), 1.49 (s, 10H), 1.58-1.77 (m, 2H), 1.92-2.19 (m, 2H), 2.90-2.99 (m, 1H), 5.80-6.10 (m, 1H).

Provenance & Evidence