4-Toluenesulfonyl chloride → HCID 118079739, compound

Participants

Reaction Conditions

Reaction Steps

A solution of crude (S)-2-(3-amino-5-bromopyridin-2-ylamino)propane-1-ol (5.85 g, 23.77 mmol) dissolved in pyridine (58 mL) was cooled to 0° C. and treated with p-toluenesulfonyl chloride (4.53 g, 23.77 mmol) in one portion. The reaction mixture was stirred at 0° C. After 45 min, the solution was concentrated under reduced pressure. The residue was partitioned between water (60 mL) and ethyl acetate. The ethyl acetate layer was separated and washed with 5% aqueous sodium chloride solution (2×50 mL) and concentrated under reduced pressure. The resulting syrup was dissolved in toluene (100 mL), which was then removed under reduced pressure in an effort to remove residual pyridine. The crude product (10.4 g) was purified by column chromatography on silica gel (eluting with 3:1 dichloromethane-ethyl acetate followed by 2:1 dichloromethane-ethyl acetate and finally 3:2 dichloromethane-ethyl acetate). The product-containing fractions were combined and concentrated. The resulting syrup was dissolved in dichloromethane and the solution diluted with heptane. The mixture was concentrated under reduced pressure to yield (S)-N-(5-bromo-2-(1-hydroxypropan-2-ylamino)pyridin-3-yl)-4-methylbenzenesulfonamide (8.6 g, 21.5 mmol, 90%) as a nearly colorless foam/solid. MS (ESI, pos. ion) m/z 400, 402 [M+1]+.

Provenance & Evidence