The synthesis of α-fluoroacrylates and α-bromo-α-fluoroalkenes was achieved in very good yields using aldehydes and ketones, triphenylphosphine, diethylzinc as promoter, and ethyl dibromofluoroacetate or dibromofluoromethane, respectively. A change in the addition sequence was critical in order to obtain exclusively α-fluoroacrylates in good yields.
A Simple, Two-Step, Site-Specific Preparation of Fluorinated Naphthalene and Phenanthrene Derivatives from Fluorobromo-Substituted Alkenes
作者:Yi Wang、Jianjun Xu、Donald J. Burton
DOI:10.1021/jo061305k
日期:2006.9.1
two-step procedure for the site-specific preparation of fluorinated naphthalene and phenanthrenederivatives is described. The Sonogashira reaction of bromofluoro-substituted alkenes with terminal alkynes, followed by base-catalyzed cyclization in refluxing N-methyl-2-pyrrolidinone (NMP), affords the corresponding fluorinated naphthalene and phenanthrenederivatives in good yields.
Synthesis of 1-bromo-1-fluoroolefins was achieved in good yields via a Wittig reaction promoted by diethylzinc, even with nonactivated aldehydes and ketones as starting materials.
Organophotocatalysis Enables the Synthesis of <i>gem</i>-Fluorophosphonate Alkenes