Reaktion #1778

Reaktionsgleichung

4-chromanol

diethyl azodicarboxylate

methyl 4-hydroxy-2-methoxybenzoate

triphenylphosphine

→

methyl 4-(4-chromanoyloxy)-2-methoxybenzoate

Lösungsmittel

THF

THF

Reaktionsbedingungen

Aufarbeitung

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

Vorschrift

To a stirred solution of methyl 4-hydroxy-2-methoxybenzoate (364 mg, 2.0 mmol) in dry THF (1.25 mL) was added triphenylphosphine (525 mg, 2.0 mmol) and the solution was cooled to 0° C. A 500 mL volume of 4-chromanol (200 mg, 1.33 mmol) and diethyl azodicarboxylate (315 mL, 2.0 mmol) in THF was added dropwise via syringe 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 92:8 hexanes:EtOAc and eluted with same. The appropriate fractions were combined and the solvent removed under reduced pressure to afford methyl 4-(4-chromanoyloxy)-2-methoxybenzoate.

Quelle