Trifluoroacetic acid → HCID 118069745, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 3-(4-amino-1,2,5-oxadiazol-3-yl)-4-(3-bromo-4-fluorophenyl)-1,2,4-oxadiazol-5(4H)-one (68 mg, 0.20 mmol; from Step D) and benzyl {[(2,2-dimethoxyethyl)amino]sulfonyl}carbamate (191 mg, 0.60 mmol, 3.0 equiv.) in 1,2-dichloroethane (3.0 mL) was cooled to 0° C. To this mixture was added trifluoroacetic acid (1.0 mL, 13.0 mmol) and triethylsilane (105 μL, 0.66 mmol, 3.3 equiv.) drop-wise. This reaction mixture was stirred at 0° C. for 2 h. HPLC indicated reaction completion. The reaction mixture was cooled to 0° C. and quenched with saturated sodium bicarbonate to pH ˜8. and the quenched reaction mixture was extracted with EtOAc (3×10 mL). The combined organic extracts were washed with brine, dried over sodium sulfate and concentrated. The residue was then stirred in a mixture of heptane and diethyl ether overnight. The solids were collected by filtration, washed with heptane and dried in vacuum to give the desired product (125 mg, 99%) as a crude off-white solid. 1H NMR (300 MHz, DMSO-d6) δ 11.31 (s, 1H), 8.05 (m, 1H), 7.87 (m, 1H), 7.68 (m, 1H), 7.56 (m, 1H), 7.32 (m, 5H), 6.54 (m, 1H), 5.07 (s, 2H), 3.29 (m, 2H), 3.09 (m, 2H); C20H17BrFN7O7S (MW 598.36), LCMS m/e 598/600 (M++H).

Provenance & Evidence