24286-45-1Relevant academic research and scientific papers
Facile synthesis of the fused 6-6-5 ring system containing chroman ring from 2-(1-hydroxy-5-alkenyl)phenol derivatives via intramolecular inverse- electron-demand diels-alder reaction
Shrestha, Kedar Shanker,Honda, Kiyoshi,Asami, Masatoshi,Inoue, Seiichi
, p. 73 - 83 (2007/10/03)
A simple and facile synthesis of the fused 6-6-5 ring system, i.e., 1,2,3,3a,4,9b-hexahydrocyclopenta[c][1]benzopyrans, was achieved through the intramolecular [4+2] cycloaddition of o-quinonemethides generated from 2-(1- hydroxy-5-alkenyl)phenol derivatives under acidic conditions. In general, cis-fused tricyclic compounds of 6-6-5 ring system were obtained as the major products. Reactivity and selectivity of the cycloaddition reaction depended on the substituents on the aromatic ring and in the dienophilic olefin moiety.
CHIRAL SYNTHESIS OF (R)-(+)-CITRONELLAL VIA STEREOSELECTIVE PROTONATION
Takano, Seiichi,Chiba, Hiroyuki,Kudo, Junko,Takahashi, Michiyasu,Ogasawara, Kunio
, p. 2461 - 2468 (2007/10/02)
Protonation of the enolates (8) and (12) generated from an epimeric mixture of the α,γ-disubstituted γ-lactone (7) is shown to yield the syn-α/γ-disubstituted γ-lactone (10) predominant over the anti-α/γ-disubstituted γ-lactone (11).When the silyl enol ether (12) generated in situ is protonated with trifluoroacetic acid, the best selectivity is obtained.The syn-epimer (10) thus obtained is converted into (R)-(+)-citronellal (17) in four steps of reactions.
Action d'organolithiens et organomagnesiens sur la propiolactone en presence de sel cuivreux Synthese d'acides carboxyliques
Normant, J. F.,Alexakis, A.,Cahiez, G.
, p. 935 - 938 (2007/10/02)
Organocuprate reagents, as well as Grignard reagents under the catalytic action of copper bromide, react with propiolactone to give the corresponding homologous acid with three more carbon atoms in good yields.
