Synthesis of gem-bromofluoroolefins using singlet bromofluorocarbene generated from ethyldibromofluoroacetate via a Wittig-type reaction

A halon-free method for the synthesis of gem-bromofluoroolefins utilizing ethyldibromofluoro-acetate is disclosed via Wittig type reaction. The reaction system takes advantage of inexpensive and readily available reagents. The method was applied to a wide variety of aryl aldehydes. Both electron donating and electron withdrawing moieties on the aryl ring were tolerated and the desired olefin products were obtained in good to excellent yields.