Design and Synthesis of Violet Odorants with Bicyclo[6.4.0]dodecene and Bicyclo[5.4.0]undecene Skeletons

Abstract

The Diels-Alder reaction of 1,2-bis(methylene)cyclooctane (13), 4-methylenespiro[2.7]decane (29), 4-methylenespiro[2.6]nonane (40) and 4-methylenespiro[2.7]dec-8-ene (46) with different a,b-unsaturated carbonyl compounds afforded various derivatives 16, 18, 20, 22, 24, 26, 32, 36, 38, 41, 42 and 47 of a molecular-modeled lead compound 9. These less flexible b-ionone-mimics with bicyclo[6.4.0]dodecene and bicyclo[5.4.0]undecene skeletons possess interesting fruity-woody-floral odor notes and provide insight into the structure-odor correlation of violet odorants. 5-(2-Methylcycloalk-1-en-1-yl)hex-3-en-2-ones (e.g. 35) were identified as byproducts of the Rh(I)-catalyzed reactions of the vinylcyclopropanes 29 and 40.

Odds and Trends: Recent Developments in the Chemistry of Odorants

“…Besides Meo Parf (93), Majantol (95), Mayol (96), and Florol (97), a derivative of rose oxide with a muguet odor and rose-petallike aspects, are representative muguet alcohols. However, aldehydes are more unstable, especially in oxidizing or alkaline media.…”

“…This is also true for rosy odorants. In ªComme des garçons 2º (Comme des garçons, 1999) about 9 % was combined with around 2.8 % of Mayol (96), and in ªSunwaterº (Lancaster, 1997) 1.4 % of 114 was used with 0.5 % of Florol (97). Compound 114 can convey the freshness of rose flower dew in compositions.…”

Allerlei Trends: die neuesten Entwicklungen in der Riechstoffchemie

“…[96] Hinsichtlich der Molekülgestalt ist ein Dimethylcyclohexenring einer Cycloocteneinheit fast gleichwertig und dies spiegelt sich auch in der erstaunlichen geruchlichen ¾hnlichkeit von 1-Bicyclo[6.4.0]dodec-1(8)-en-10-ylethan-1-on 174 mit b-Jonon 173 wider. [96] Hinsichtlich der Molekülgestalt ist ein Dimethylcyclohexenring einer Cycloocteneinheit fast gleichwertig und dies spiegelt sich auch in der erstaunlichen geruchlichen ¾hnlichkeit von 1-Bicyclo[6.4.0]dodec-1(8)-en-10-ylethan-1-on 174 mit b-Jonon 173 wider.…”

Present and Future of Cyclopropanations in Fragrance Chemistry

“…Cycloaddition of Vinylcyclopropanes. An intermolecular version of the Rh I -catalyzed cycloaddition of vinylcyclopropanes [42] has been developed by Kraft (Scheme 21) who applied it to the synthesis of various fragrance compounds such as Georgywood isomer 66 [43]. Rhodacyclic intermediates such as 64a and 64b have been proposed by Kraft and Wender.…”