Diethylzinc-mediated one-step stereoselective synthesis of [alpha]-fluoroacrylates from aldehydes and ketones: two different pathways depending on the carbonyl partner

An efficient method is developed that has allowed the one-pot stereoselective synthesis of [alpha]-fluoroacrylates, which is based on the addition of ethyl dibromofluoroacetate to a carbonyl derivative using diethylzinc as organometallic mediator. Two different pathways are identified depending on the carbonyl partner and in the case of aldehydes, an E2-type mechanism is identifies, whereas ketones go through an E1cb-type mechanism.