反应详情

A solution of 4-bromo-3,5-dimethoxybenzaldehyde (5.04 g, 20.57 mmole) and toluenesulfonylmethyl isocyanide (4.22 g, 21.6 mmole) in MeOH (50 ml) was heated at reflux for 3 hrs. After evaporation to near dryness, H2O (50 ml) and EtOAc (200 ml) were added with stirring. The organic layer was separated and washed with brine (50 ml), dried over Na2SO4 and concentrated in vacuo. Et2O (50 ml) was added with swirling and the product was collected by filtration, washed with Et2O (2×25 ml) and dried giving 5-(4-bromo-3,5-dimethoxyphenyl)oxazole as a pale yellow solid (2.25 g, 39% yield).

1. temperatureat reflux for 3 hrs
2. customAfter evaporation
3. additionwere added
4. customThe organic layer was separated
5. washwashed with brine (50 ml)
6. dry with materialdried over Na2SO4
7. concentrationconcentrated in vacuo
8. additionEt2O (50 ml) was added
9. filtrationthe product was collected by filtration
10. washwashed with Et2O (2×25 ml)
11. customdried