Zinc-Diethylaluminium Chloride Induced Coupling Reaction of Dibromofluoroacetate with Carbonyl Compounds. New Efficient and Selective Synthesis of α-Bromo-α-fluoro-β-hydroxy and α-Fluoro-β,β′-dihydroxy Esters
Treatment of ethyl dibromofluoroacetate with aldehydes or ketone in the presence of zinc and diethylaluminium chloride at −20 °C gave rise to the corresponding α-bromo-α-fluoro-β-hydroxy alkanoic a...
Treatment of α-bromo-α-fluoro-β-hydroxy esters with trimethylaluminum in dichloromethane, followed by reaction with allylic stannanes and a catalytic amount of triethylborane at −15°C, gave the corresponding threo-α-allylated α-fluoro-β-hydroxy esters in a highly stereoselective manner. On the other hand, the reaction of the β-hydroxyesters with allylic stannanes under the influence of a catalytic