反应详情

To a solution of 4-bromo-2-methoxybenzaldehyde (5.2 g, 24.2 mmol) in methanol (20 ml) and trimethylorthoformate (14 ml, 5.5 eq.) was added p-toluenesulfonic acid (46 mg, 0.01 eq.) and the mixture was refluxed for 3 hr. Potassium carbonate (125 mg, 0.03 eq.) and silicagel was added, the solvent was removed under reduced pressure and the solid residue packed into a loading column and purified by MPLC (hexanes-ethylacetate 40-80% gradient). MS (EI+): 262, 260 (1/1, M+, 10%); 231, 229 (1/1, 90%); 215, 213 (1/1, 10%); 199, 170, 150, 118, 92, 75, 45 (100%).

1. temperaturethe mixture was refluxed for 3 hr
2. customthe solvent was removed under reduced pressure
3. custompurified by MPLC (hexanes-ethylacetate 40-80% gradient)