Methanesulfonic Acid → 7-bromo-8-fluoro-3-(3-methoxy-3-methylbut-1-ynyl)-5'H-spiro[chromeno[2,3-b]pyridine-5,4'-oxazol]-2'-amine

Participants

Reaction Steps

A solution of 4-(2′-amino-7-bromo-8-fluoro-5′H-spiro[chromeno[2,3-b]pyridine-5,4′-oxazole]-3-yl)-2-methylbut-3-yn-2-ol (0.580 g, 1.342 mmol) in 10 mL MeOH was treated with methanesulfonic acid (0.871 mL, 13.42 mmol). The resulting solution was allowed to stir at RT for 72 hours and was then heated at 85° C. for 3 hours. The reaction mixture was poured into saturated NaHCO3 (50 mL) and was extracted with EtOAc (3×25 mL). The organics were washed with brine, dried over MgSO4 and concentrated in vacuo. Purification of the crude residue by column chromatgraphy [0-100% (95:5 EtOAc/MeOH)/CH2Cl2] afforded 7-bromo-8-fluoro-3-(3-methoxy-3-methylbut-1-ynyl)-5′H-spiro[chromeno[2,3-b]pyridine-5,4′-oxazol]-2′-amine

Provenance & Evidence