Reaction #1770

Reaction equation

tetrahydro-4H-pyran-4-ol

diethyl azodicarboxylate

methyl 4-hydroxy-2-methoxybenzoate

triphenylphosphine

→

methyl 4-(4-tetra-hydropyranoyloxy)-2-methoxy-benzoate

Solvents

THF

THF

Conditions

Workup

1. 1
   FiltrationThe reaction was filtered
2. 2
   Otherthe solvent was removed under reduced pressure
3. 3
   OtherThe residue was chromatographed on a silica gel column
4. 4
   WashEtOAc and eluted with same
5. 5
   Otherthe solvent removed under reduced pressure

Procedure

To a stirred solution of methyl 4-hydroxy-2-methoxybenzoate (713 mg, 3.92 mmol) in dry THF (7.5 mL) was added triphenylphosphine (1.42 g, 5.4 mmol) and the solution was cooled to 0° C. A 2.5 mL volume of tetrahydro-4H-pyran-4-ol (466 mL, 4.90 mmol) and diethyl azodicarboxylate (850 μL, 5.4 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-tetra-hydropyranoyloxy)-2-methoxy-benzoate.

Source