Multisubstituted α,β-Unsaturated γ-Lactones from 1-Chlorovinyl p-Tolyl Sulfoxides and tert-Butyl Carboxylates Using Pummerer-Type Cyclization as the Key Reaction
Multisubstituted α,β-Unsaturated γ-Lactones from 1-Chlorovinyl p-Tolyl Sulfoxides and tert-Butyl Carboxylates Using Pummerer-Type Cyclization as the Key Reaction
respectively, by the sulfoxide-magnesium exchange reaction in high yields. Comparing the stability of the γ-chloromagnesio γ-lactones with that of the δ-chloromagnesio δ-lactones, the former was found to be much more stable. The reaction of these γ-chloromagnesio γ-lactones and δ-chloromagnesio δ-lactones with electrophiles and the stereochemistry of the reactions are discussed. γ-chloromagnesio γ-lactone