Trifluoroacetic anhydride → N-[(R)-1-(5-bromo-2-fluoro-phenyl)-2-((R)-1-cyano-2,2,2-trifluoro-1-methyl-ethoxy)-1-methyl-ethyl]-2-nitro-benzenesulfonamide

Participants

Reaction Conditions

Reaction Steps

To a solution of (R)-2-[(R)-2-(5-bromo-2-fluoro-pheyl)-2-(2-nitro-benzenesulfonylamino)-propoxy]-3,3,3-trifluoro-2-methyl-propionamide (20.83 g, 35.6 mmol) in CH2Cl2 (300 ml) was added under argon NEt3 (12.5 ml, 89 mmol) and at 0-5° C. trifluoroacetic anhydride (6.15 ml, 42.7 mmol). After stirring for 4 h at 25° C. the reaction mixture was added to a cold NaHCO3 solution and the product was extracted with CH2Cl2. Combined extracts were washed with cold 0.1N aqueous HCl, water and saturated NaHCO3 solution, dried over MgSO4, filtered and concentrated to provide the title compound as a yellow oil, which was used as such for the next step: TLC (hexane-EtOAc 1:1): Rf=0.73; UPLC RtH5=1.364 min; ESIMS: 571, 573 [(M+NH4)+]; 1H NMR (360 MHz, CDCl3): δ 7.89 (d, 1H), 7.62 (ddd, 1H), 7.57 (ddd, 1H), 7.52 (m, 2H), 7.29 (m, 1H), 6.58 (dd, 1H), 6.19 (s, 1H), 4.17 (s, 2H), 1.81 (s, 3H), 1.72 (s, 3H).

Provenance & Evidence