To a stirred solution of methyl 4-hydroxy-2-methoxybenzoate (364 mg, 2.0 mmol) in dry THF (4 mL) was added triphenylphosphine (524.6 mg, 2.0 mmol) and the solution was cooled to 0° C. A 2.5 mL volume of sulfonylpyran-4-ol (200 mg, 1.33 mmol) and diethyl azodicarboxylate (315 μL, 2.0 mmol) in THF was added dropwise via addition funnel over 0.5 h. The reaction was filtered and the solvent was removed under reduced pressure. The residue was chromatographed on a silica gel column packed in 60:40 hexanes:EtOAc and eluted with same. The appropriate fractions were combined and the solvent removed under reduced pressure to afford methyl 4-[4-sulfonylpyranoyloxy]-2-methoxybenzoate.
