Anionic cascade reactions. One-pot assembly of (Z)-chloro-exo-methylenetetrahydrofurans from β-hydroxyketones

Abstract

The assembly of (Z)-chloro-exo-methylenetetrahydrofurans by an original and connective anionic cascade sequence is reported. Base-catalysed condensation of β-hydroxyketones with 1,1-dichloroethylene generates, in moderate to good yields, the corresponding (Z)-chloro-exo-methylenetetrahydrofurans. Acidic treatment of this motif leads to several unexpected dimers, possessing unique structural features.

Keywords

• acetylene addition
• dichloroethylene
• dimerisation
• dioxanes
• tetrahydrofurans