反应详情

In dry environment under N2, 2-(4-methoxy-phenyl)-4,4-dimethyl-4,5-dihydro-oxazole (20 g, 0.097 mole), prepared as described in example 1, was dissolved in ethyl ether (200 ml) and added at −2° C. with n-butyl lithium (44 ml, 0.11 mole), keeping the temperature below 5° C. The mixture was stirred and after 4 hours added with DMF (15.4 g, 16.3 ml, 0.21 mole). After stirring overnight at room temperature, the mixture was cooled and extracted with water/ice. The aqueous phase was extracted again with ethyl ether. The organic phase was washed with water/NaCl, discoloured with charcoal, anhydrified and concentrated under vacuum to give 19 g of the title compound (yield: 84%). 1H-NMR (CDCl3) δ: 10.75(s,1H); 7.84-7.05(m,3H); 4.10(s,2H); 3.86(s,3H); 1.37(s,6H).

1. customthe temperature below 5° C
2. stirringAfter stirring overnight at room temperature
3. temperaturethe mixture was cooled
4. extractionextracted with water/ice
5. extractionThe aqueous phase was extracted again with ethyl ether
6. washThe organic phase was washed with water/NaCl
7. concentrationconcentrated under vacuum