反应详情

To a mixture of 6,7-dichloro-5-hydroxy-α,α-dimethylbenzo[b]thiophene-2-methanol in 250 ml of 2-butanone is added a solution of 7.7 g of t-butyl bromoacetate in 50 ml 2-butanone and the resultant mixture is placed in a preheated oil-bath at 95°. To the mixture is added 6.7 g of potassium carbonate and 3 ml of dimethylformamide and the reaction mixture is refluxed at 95° for 21/2 hrs. The cooled mixture is filtered and 100 ml of water is added. The layers are separated and the aqueous phase is extracted two times with ethyl ether. The organic extracts are washed, dried over anhydrous magnesium sulfate, filtered and concentrated to give a solid. Recrystallization from ethyl ether and pentane gives 11.5 g of t-butyl [[6,7-dichloro-2-(1-hydroxy-1-methylethyl)benzo[b]thien-5-yl]oxy]acetate, mp 137°-138°.

1. temperaturethe reaction mixture is refluxed at 95° for 21/2 hrs
2. filtrationThe cooled mixture is filtered
3. addition100 ml of water is added
4. customThe layers are separated
5. extractionthe aqueous phase is extracted two times with ethyl ether
6. washThe organic extracts are washed
7. dry with materialdried over anhydrous magnesium sulfate
8. filtrationfiltered
9. concentrationconcentrated
10. customto give a solid
11. customRecrystallization from ethyl ether and pentane