64129-96-0Relevant articles and documents
Competitive Gold-Promoted Meyer-Schuster and oxy-Cope Rearrangements of 3-Acyloxy-1,5-enynes: Selective Catalysis for the Synthesis of (+)-(S)-γ-Ionone and (-)-(2S,6 R)-cis-γ-Irone
Bugoni, Serena,Merlini, Valentina,Porta, Alessio,Gaillard, Sylvain,Zanoni, Giuseppe,Nolan, Steven P.,Vidari, Giovanni
, p. 14068 - 14074 (2015)
We report a simple, highly stereoselective synthesis of (+)-(S)-γ-ionone and (-)-(2S,6R)-cis-γ-irone, two characteristic and precious odorants; the latter compound is a constituent of the essential oil obtained from iris rhizomes. Of general interest in this approach are the photoisomerization of an endo trisubstituted cyclohexene double bond to an exo vinyl group and the installation of the enone side chain through a [(NHC)AuI]-catalyzed Meyer-Schuster-like rearrangement. This required a careful investigation of the mechanism of the gold-catalyzed reaction and a judicious selection of reaction conditions. In fact, it was found that the Meyer-Schuster reaction may compete with the oxy-Cope rearrangement. Gold-based catalytic systems can promote either reaction selectively. In the present system, the mononuclear gold complex [Au(IPr)Cl], in combination with the silver salt AgSbF6 in 100:1 butan-2-one/H2O, proved to efficiently promote the Meyer-Schuster rearrangement of propargylic benzoates, whereas the digold catalyst [{Au(IPr)}2(μ-OH)][BF4] in anhydrous dichloromethane selectively promoted the oxy-Cope rearrangement of propargylic alcohols.
Synthesis and olfactory evaluation of (+)- and (-)-γ-ionone
Fuganti, Claudio,Serra, Stefano,Zenoni, Alessandro
, p. 2761 - 2768 (2007/10/03)
The synthesis of enantiomerically pure (+)- and (-)-γ-ionone 3 is reported. The first step in the synthesis is the diastereoisomeric enrichment of 4-nitrobenzoate derivatives of racemic γ-ionol 12. The enantioselective lipase-mediated kinetic acetylation