Catechol → 1,4-Benzodioxan 2-ethylcarboxylate

Reaction equation

[OH:1][C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][C:3]=1[OH:8].C(=O)([O-])[O-].[K+].[K+].[C:15]([O:19]CC(Br)Br)(=[O:18])[CH2:16][CH3:17]>CC(C)=O>[O:1]1[C:2]2[CH:7]=[CH:6][CH:5]=[CH:4][C:3]=2[O:8][CH2:16][CH2:15]1.[CH3:17][CH2:16][C:15]([O-:19])=[O:18]

Participants

Procedure

Ortho-dihydroxybenzene (11 g, 100 mmol) and anhydrous acetone (70 mL) were refluxed under nitrogen. Potassium carbonate (5 g, 36 mmol), dibromoethyl propionate (6.56 g, 25.3 mmol) were added portion-wise in sequence over a period of 1.5 hours. After 4 hours, the reaction was completed, which was confirmed by thin film chromatography. The crude product was cooled to room temperature, concentrated under reduced pressure to remove acetone, added with NaHCO3 solution, and extracted with ethyl acetate. The organic layer was dried with anhydrous sodium sulfate, and condensed to afford 18.51 g the product (89% yield).