99734-54-0Relevant academic research and scientific papers
Regio- and Stereoselective Ring Opening of ω-Alkenyllactones Using Organocopper Reagents
Kawashima, Masatoshi,Sato, Toshio,Fujisawa, Tamotsu
, p. 3255 - 3264 (2007/10/02)
New synthetic methods are described for the preparation of (E)-3, (E)-4, and (E)-5-alkenoic acids by the regio- and stereoselective ring opening of β, γ, and δ-lactones with unsaturated substituents at the ω-position using organocopper reagents such as halomagnesium diorganocuprates or Grignard reagents in the presence of copper(I) iodide.Both the organocopper reagents with primary, secondary, tertiary alkyl, and phenyl groups gave the corresponding carbon homologated alkenoic acids in good yields.Alkadienoic acids were also obtained in good yields by the reactions of ω-alkenyllactones with divinyl- and diallylcuprates.Utilizing the ring opening of β-isopropenyl-β-propiolactone, homoterpenoid carboxylic acids were easly obtained in good yields.The ring opening of β-(1-chlorovinyl)-β-propiolactone afforded 4-chloro-3-alkenoic acids which were easly transformed to 4-oxoalkanoic acids and 4-oxo-2-alkenoic acids.
ONE-STEP SYNTHESIS OF HOMOTERPENOIC ACIDS FROM Β-ISOPROPENYL-Β-PROPIOLACTONE AND ORGANOCOPPER REAGENTS
Fujisawa, Tamotsu,Sato, Toshio,Kawashima, Masatoshi,Nakagawa, Masakuni
, p. 1307 - 1310 (2007/10/02)
Regioselective reaction of Grignard reagents in the presence of a copper(I) catalyst or of organocuprates with the terminal vinyl carbon of β-isopropenyl-β-propiolactone through the SN2'pathway affords 4-methyl-3-alkenoic acids in which the (E)
