Ethyl Acetate → Trifluoro-methanesulfonic acid 6-methyl-8-nitro-5-oxo-2,3-dihydro-5H-thiazolo[3,2-a]pyridin-7-yl ester

Participants

Reaction Steps

Triflic anhydride (3.4 g, 12.06 mmol) was added to a stirred solution of 7-hydroxy-6-methyl-8-nitro-2,3-dihydro-thiazolo[3,2-a]pyridin-5-one (2.5 g, 10.96 mmol) and TEA (2.3 mL, 16.44 mmol) in DCM (20 mL) at −70° C. The resulting mixture was stirred at −70° C. to −50° C. for 2 hours. The reaction mixture was monitored by TLC (50% ethylacetate in hexane). The reaction mixture was diluted DCM and quenched with bicarbonate solution. The organic layer was washed with brine solution, dried over Na2SO4 and concentrated. Purification by column chromatography on silica gel (30% ethylacetate in hexane) afforded 0.9 g of the product (38% yield).

Provenance & Evidence