反应详情

4 g of the product of Step A and 3.5 g of dicyclohexylcarbodiimide were added to a solution of 20 ml of methylene chloride and 1 ml of pyridine and the reaction mixture was stirred for 1 hour. 2.15 g of trifluoroethanol and 5 ml of methylene chloride were then added to the mixture which was stirred at 20° C. for 16 hours and was filtered. The filtrate was rinsed with methylene chloride and the filtrate was evaporated to dryness. The residue was taken up in ether and the solution was washed with N hydrochloric acid, then with water and dried and evaporated to dryness. The 5 g of residue was chromatographed over silica gel and was eluted with a 95-5 benzene-ethyl acetate mixture to obtain 3.5 g of 1,1-dimethylethyl (1R,cis) 2,2-dimethyl-3-[3-oxo-3-(2,2,2-trifluoroethoxy)-1-propynyl]-cyclopropane-carboxylate.

1. stirringwas stirred at 20° C. for 16 hours
2. filtrationwas filtered
3. washThe filtrate was rinsed with methylene chloride
4. customthe filtrate was evaporated to dryness
5. washthe solution was washed with N hydrochloric acid
6. dry with materialwith water and dried
7. customevaporated to dryness
8. customThe 5 g of residue was chromatographed over silica gel
9. washwas eluted with a 95-5 benzene-ethyl acetate mixture