反应详情

温度

0 °C

1.6 g of p-toluene sulonic acid monohydrate were added to a solution of 16.4 g of the product of Step B in 160 ml of toluene and the mixture was refluxed until gas evolution ceased (about 30 minutes) and was cooled to 0° C. and filtered The filtrate was evaporated to dryness under reduced pressure and the residue was chromatographed over silica gel. Elution with a 70-30-1 n-hexane-ethyl acetate-acetic acid mixture yielded 13.3 g of (S)α-cyano-3-phenoxy-4-fluoro-benzyl (1R,cis,Z) 2,2-dimethyl-3-[3-oxo-3-hydroxy-1-propenyl]-cyclopropane-carboxylate melting at 99° C. and having a specific rotation of [α]D20 =+52.5° ±2.5° (c=0.5% in chloroform).

1. temperaturethe mixture was refluxed until gas evolution
2. custom(about 30 minutes)
3. filtrationfiltered The filtrate
4. customwas evaporated to dryness under reduced pressure
5. customthe residue was chromatographed over silica gel
6. washElution with a 70-30-1 n-hexane-ethyl acetate-acetic acid mixture