反应详情

A mixture of 5 g of the product of Step A, 250 mg of p-toluene sulfonic acid and 30 ml of toluene was refluxed for one hour and was cooled and chromatographed over silica gel. Elution with a 1-1 hexane-ethyl acetate mixture containing 1% of acetic acid and crystallization from isopropyl ether yielded 3.05 g of benzyl(1R,cis,Z)2,2-dimethyl-3- [3-oxo-3-hydroxy-1-propenyl]-cyclopropane-carboxylate melting at 69° C.

1. temperaturewas refluxed for one hour
2. temperaturewas cooled
3. customchromatographed over silica gel
4. washElution with a 1-1 hexane-ethyl acetate mixture
5. additioncontaining
6. custom1% of acetic acid and crystallization from isopropyl ether