1320211-13-9Relevant articles and documents
Multisubstituted α,β-unsaturated γ-lactones from 1-chlorovinyl p-tolyl sulfoxides and tert-butyl carboxylates using Pummerer-type cyclization as the key reaction
Katae, Takashi,Sugiyama, Shimpei,Satoh, Tsuyoshi
, p. 1435 - 1441 (2011/06/21)
The addition reaction of 1-chlorovinyl p-tolyl sulfoxides, derived from aldehydes and chloromethyl p-tolyl sulfoxide, with the lithium enolate of tert-butyl carboxylates gave adducts in quantitative yields. Treatment of the adducts with trifluoroacetic anhydride in the presence of sodium iodide resulted in the formation of γ-lactones bearing a p-tolylsulfanyl group at the γ-position through Pummerer-type cyclization. Oxidation of the sulfanyl group to the sulfinyl group followed by thermal syn-elimination gave α,β-unsaturated γ-lactones (γ-butenolides) in moderate to good yields. Trapping the intermediates of the addition reaction with iodoalkanes gave alkylated adducts, from which α,γ;- and β,γ-disubstituted γ-butenolides were obtained. These procedures provide a good way to synthesize multisubstituted γ-butenolides from aldehydes. Georg Thieme Verlag Stuttgart New York.