hydroxylamine-O-sulfonic acid → 2-(5-Bromothiazol-2-yl)propane-2-sulfonamide

Participants

Reaction Steps

The product of Step 4 (2.50 g, 7.02 mmol) was taken up in THF (80 mL) at room temperature, and NaOMe (25% in MeOH, 1.52 g, 7.02 mmol) was added. After 30 min at room temperature, the suspension was evaporated to dryness, providing a white solid. The solid was taken up in water (50 mL), and a solution of NaOAc (3.17 g, 38.6 mmol) and hydroxylamine-O-sulfonic acid (3.97 g, 35.1 mmol) in water (25 mL) was added while cooling the reaction (0° C.). The reaction was vigorously stirred at room temperature overnight (a white solid precipitated after 15-30 min). The reaction was extracted with ethyl acetate (2×). The combined organic layers were washed with brine, dried (MgSO4), filtered and evaporated. The resulting white residue was triturated with CH2Cl2 and filtered to provide 2-(5-bromo-1,3-thiazol-2-yl)propane-2-sulfonamide (1.58 g, 79%) as a white powder. ESI: [M+H]+ m/z 284.9/286.9.

Provenance & Evidence