反应详情

The 3-bromo-2-methyl-benzaldehyde ((Example 6: step c) 813 mg, 4.08 mmol) was dissolved in dry MeOH (50 mL) and trimethyl orthoformate (8 mL). Toluenesulfonic acid (100 mg) was added and the solution was stirred for 6 h at rt. Solid NaHCO3 (200 mg) was added, the solution was stirred for 30 min, and the volatile components were removed in vacuo. The residue was dissolved in dry EtOAc (10 mL), the solution was filtered (45 micron filter), and the solvent was removed in vacuo. 1H NMR analysis of the crude material (918 mg, 92%) revealed approximately a 90% conversion of the starting material to the title compound, which was used without further purification. 1H-NMR (CDCl3): δ 7.47 (dd, 1H, J=1.2, 8.1 Hz), 7.44 (dd, 1H, J=0.9, 7.9 Hz), 6.99 (t, 1H, J=7.9 Hz), 5.37 (s, 1H), 3.25 (s, 6H), 2.37 (s, 3H).

1. stirringthe solution was stirred for 30 min
2. customthe volatile components were removed in vacuo
3. dissolutionThe residue was dissolved in dry EtOAc (10 mL)
4. filtrationthe solution was filtered
5. filtration(45 micron filter)
6. customthe solvent was removed in vacuo
7. customwas used without further purification