A Facile and Mild Method for the Synthesis of Terminal Bromofluoroolefins via Diethylzinc-Promoted Wittig Reaction
摘要:
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.
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.
The reactions of fluorinated ylide, generated from tris(dimethylamino)phosphine and tribromofluoromethane, with simple aldehydes and reactive ketones gave the expected Wittig reaction products. How...
A highly diastereoselective and straightforward synthesis for (Z)-2-fluoroallylic alcohols via a Nozaki−Hiyama−Kishi-type reaction with the corresponding bromofluoroolefins was developed, providing an easy access to highly interesting fluorinated synthons.
This work describes the first transition metal-free stereospecificsynthesis of (E)-(1-fluoro-2-arylvinyl)phosphine boranes through the addition of diarylphosphido-boranes to gem-bromofluoroalkenes at room temperature. The reaction proceeds well under very mild conditions...