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
The first example of γ-chloromagnesio γ-lactones: their generation from γ-tolylsulfinyl γ-lactones with isopropylmagnesium chloride, stability, and reaction with electrophiles
作者:Shimpei Sugiyama、Hitomi Shimizu、Tsuyoshi Satoh
DOI:10.1016/j.tetlet.2006.09.165
日期:2006.12
The treatment of gamma-lactones having a sulfinyl group at the gamma-position, which were synthesized from I-chlorovinyl p-tolyl sulfoxides with lithium enolate of carboxylic esters, with isopropyl magnesium chloride in THF at -78 degrees C gave gamma-chloromagnesio gamma-lactones by the sulfoxide-magnesium exchange reaction in high yields. The generated gamma-chloromagnesio gamma-lactones were found to be stable at below -50 degrees C for at least 2 h. The reaction of these gamma-chloromagnesio gamma-lactones with electrophiles and the stereochemistry of the reactions were investigated. (c) 2006 Elsevier Ltd. All rights reserved.