反应详情

温度

0 °C

A solution of 2-(4-methoxy-phenyl)-4,4-dimethyl-4,5-dihydro-oxazole (4.5 g, 21.9 mmoles), prepared as described in example 1, in dry ethyl ether (90 ml), under stirring and N2 at 0° C., was added with 2.5M n-butyl lithium (9.6 ml, 24.1 mmoles) in hexane. The reaction went on for 4 hours. In another flask a suspension of ZnCl2 (4.48 g, 33 mmoles) in dry ethyl ether (60 ml) was prepared and, at 0° C., dropwise added with the solution of the lithium derivative. At the end of the addition, the mixture was left at room temperature for 1.5 hours, then cooled to 0° C. and sequentially added with palladium acetate (0.25 g, 1.09 mmoles), triphenylphosphine (0.57 g, 2.19 mmoles) and, after 5 minutes, with propanoyl chloride (2.13 g, 23.02 mmoles). The mixture was left to stand for 20 hours, then poured into water/ice and extracted with ethyl acetate. The organic phase was anhydrified, discoloured and brought to dryness to give 6.6 g of the title compound (yield: 75%)

1. customwent on for 4 hours
2. customwas prepared and, at 0° C.
3. additionAt the end of the addition
4. waitThe mixture was left
5. waitto stand for 20 hours
6. extractionextracted with ethyl acetate