Abstract
High yields of γ-alkyl, -silyl and -aryl-substituted difluoropropargyl bromides have been obtained by monitoring concentration and temperature in the reaction between CF2 Br2 and γ-substituted lithium acetylide. γ-Silyl substituents afforded the corresponding α,α,α-difluorobromopropargyl alcohols in good yields via cleavage of tetrabutylammonium fluoride in the presence of an aldehyde.
Key words
alkynylation - fluorine - building block - substituent effect
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