81752-87-6Relevant articles and documents
Synthesis of three putative kairomones of the beech leaf-mining weevil Orchestes fagi (L.)
Mayo,Silk,Abeysekera,MaGee
, p. 1124 - 1132 (2016/07/21)
The beech leaf-mining weevil, Orchestes fagi (L.), also known as the beech flea weevil, is a common and widespread pest of beech, Fagus sylvatica L., in its native Europe. It now appears to be well established in Nova Scotia, Canada. We report a novel synthesis of 9-geranyl-p-cymene and syntheses of 9-geranyl-α-terpinene and 1,1-dimethyl-3-methylene-2-vinylcyclohexane, making partial use of known methods. All three of these compounds are found in beech leaf volatiles and/or wood and are putative kairomones of the beech leaf-mining weevil.
Syntheses of the enantiomers of γ-cyclogeranic acid, γ-cyclocitral, and γ-damascone: Enantioselective protonation of enolates
Fehr,Galindo
, p. 539 - 552 (2007/10/02)
(R)- and (S)-γ-cyclogeranic acid ((R)- and (S)-9, resp.) were obtained by resolution of the racemate, and their absolute configurations determined by chemical correlation. The γ-acids (R)- and (S)-9 were converted into (R)- and (S)-methyl γ-cyclogeranate ((R)- and (S)-6, resp.), and (R)- and (S)-γ-damascone ((R)- and (S)-5, resp.). A more direct entry to (R)- and (S)-9 consisted in the enantioselective protonation of a thiol ester enolate with (-)- or (+)-N-isopropylephedrine ((-)- or (+)-20) and subsequent hydrolysis of the (R)- and (S)-S-phenyl γ-thiocyclogeranate ((R)- and (S)-24, resp.; 97% ee). The esters (R)- and (S)-24 were also used as precursors of (R)- and (S)-γ-damascone ((R)- and (S)-5, resp.). Alternatively, (S)-5 (75% ee) was obtained by enantioselective protonation of ketone enolate 29 with (-)-N- isopropylephedrine ((-)-20). Organoleptic evaluation demonstrated that the (S)-enantiomers of methyl γ-cyclogeranate and γ-damascone are markedly superior to their (R)-enantiomers.
β-Cleavage of Bis(homoallylic) Potassium Alkoxides. Synthesis of γ-Damascone
Snowden, Roger L.,Linder, Simon M.
, p. 1587 - 1597 (2007/10/02)
Starting from the γ-lactone cis-1, two new syntheses of γ-damascone ((E)-4) are described.In both syntheses, the key step involves the β-cleavage of a bis(homoallylic)potassium alkoxide, viz. the transformation of 3a to 20 and (E/Z)-4, and the conversion
