Cycloaddition reactions of ethyl ( E)- and ( Z)-3-fluoropropenoate

Abstract

Ethyl ( Z)-3-fluoropropenoate ( Z-5) has been prepared in a pure state in 68% yield by a Wittig procedure developed by Burton. Ethyl ( E)-3-fluoropropenoate ( E-6) was prepared in 38% yield following the synthetic method of Purrington. The Z isomer gives cycloaddition with 1,3-diphenylisobenzofuran and cyclopentadiene to give a product with completely endo configurations. The E isomer also gives cycloadducts with same dienes to give mixtures of endo and exo products.