Total synthesis of (±)−jolkinolide A, B, and E utilizing a new mild esterification followsd by intramolecular Wittig-Horner reaction
作者:Shigeo Katsumura、Akihiko Kimura、Sachihiko Isoe
DOI:10.1016/0040-4020(89)80132-2
日期:1989.1
Jolkinolide A, B, and E were efficiently synthesized from 9-methoxy-carbonyl-4,4,10-trimethyl-Δ6-8-octalone 8 through Δ8(14)-podocalpen-13-one . A new synthetic method of γ-ylidenbutenolide consisting of mild esterification and the succeeding intramolecular Wittig-Horner reaction of α-diketone was developed.
An efficient approach to chiral nonracemic trans- and cis-decalin scaffolds for drimane and labdane synthesis
作者:Gian Piero Pollini、Anna Bianchi、Alberto Casolari、Carmela De Risi、Vinicio Zanirato、Valerio Bertolasi
DOI:10.1016/j.tetasy.2004.07.064
日期:2004.10
Optically active trans- and cis-ring junction decalinic intermediates, which represent useful precursors for the synthesis of more complex natural targets, have been conveniently prepared starting from the β-ketoester 2 obtained by standard chemistry from β-ionone and dimethyl carbonate. The chiral auxiliary (−)-menthol, easily attached to 2 through DMAP-catalyzed transesterification, allowed a clean separation
Photochemical reaction of β-ionone derivatives in the presence of oxygen. A convenient synthesis of substituted 1,2,4-trioxanes
作者:Mirta P Mischne、Silvia N Huber、Juan Zinczuk
DOI:10.1139/v99-001
日期:1999.2.1
convenient method for the preparation of substituted 1,2,4-trioxanes. The scope of the one-pot photooxidation of β-ionones has been extended to include derivatives bearing additional functionalities in the beta-ionone ring. The relative stereochemistry of the products has been established by analysis of 1H and 13C NMR spectra.Key words: 1,2,4-trioxanes, photooxidation, cyclic peroxides, tetrahydrobenzopyranes
THERMAL ELECTROCYCLIC REACTION OF 4-CARBOMETHOXY-3-[<i>CIS</i>-2-(2,6,6-TRIMETHYL-1-CYCLOHEXENYL) VINYL] CYCLOHEX-2-EN-1-ONE
作者:Tong Hei Kim、Sachihiko Isoe
DOI:10.1246/cl.1983.539
日期:1983.4.5
Thermal cyclization of titled cis-trienone 3 leads to a mixture of tricyclic ketone 4 and an unexpected aromatic ketone 5, the latter being derived by the elimination of methyl group.
The beta-keto esters of formula I are useful for the delivery of organoleptic compounds, especially for flavours, fragrances and masking agents and antimicrobial compounds.