41641-14-9Relevant academic research and scientific papers
First total synthesis and assignment of the stereochemistry of crispatenine
Bourdron, Julien,Commeiras, Laurent,Audran, Gerard,Vanthuyne, Nicolas,Hubaud,Parrain, Jean-Luc
, p. 3770 - 3775 (2008/02/04)
(Figure Presented) The first racemic and enantioselective synthesis of crispatenine 1 has been achieved, which involved a few steps, enabling the assignment of the absolute and relative configurations.
A conjugate addition-radical cyclisation approach to sesquiterpene-phenol natural products
Crombie, Barry S.,Smith, Colin,Varnavas, Christalla Z.,Wallace, Timothy W.
, p. 206 - 215 (2007/10/03)
A conjugate addition-radical cyclization approach to sesquiterpenephenol natural products was discussed. The first step involved the conjugate addition of an organocopper species to a chromone-3-carboxylate which resulted in 2,2-disubstituted chroman-4-ones. The second step was the generation of a β-ketoester radical. The last step involved a stereoselective manganese(III) acetate-mediated radical cyclization reaction.
Synthesis of mono- and sesquiterpenoids, XXV: Synthesis of (6R*,7R*)-7-hydroxy-6,11-cyclofarnes-3(15)-en-2-one, the racemate of the antibacterial sesquiterpene from premna oligotricha, and its (6R*,7R*) isomer
Yajima, Arata,Takikawa, Hirosato,Mori, Kenji
, p. 891 - 897 (2007/10/03)
The structure of the antibacterial sesquiterpene from Premna oligotricha was shown to be not 1 but 2 (relative stereochemistry) by the unambiguous synthesis of both (±)-1 and (±)-2. VCH Verlagsgesellschaft mbH, 1996.
ASYMMETRIC AZA-CLAISEN REARRANGEMENT: SYNTHESIS OF (+)-DIHYDROPALLESCENSIN-2
Kurth, Mark J.,Soares, Christopher J.
, p. 1031 - 1034 (2007/10/02)
Synthetic confirmation of the C(1')-(S)-configuration of (+)-dihydropallescensin-2 (1) is reported, the key reaction being a chiron-mediated asymmetric aza-Claisen rearrangement (67).
New Synthesis of γ-Homocyclogeranial, γ-Dihydroionone and Their Derivatives
Kawanobe, Tsuneo,Kogami, Kunio,Hayashi, Kazuo,Matsui, Masanao
, p. 461 - 464 (2007/10/02)
A new and efficient synthesis of γ-homocyclogeranial (4), γ-dihydroionone (3) and their derivatives, 5, 6, 7 and 8, volatile components of ambergris, is described.Their compounds were synthesized via Claisen rearrangement of (3,3-dimethylcyclohexenyl)methyl vinyl ether (14).
Synthesis of trans-γ-Monocyclofarnesol
Vig, O. P.,Sharma, M. L.,Trehan, Navneet,Verma, N. K.
, p. 450 - 452 (2007/10/02)
The starting material, 2-formyl-6,6,dimethylcyclohexanone (II) in the synthesis of the title compound, is converted into the corresponding 2-isobutoxymethylene-6,6-dimethylcylohexanone (III).Reduction of (III) with LAH followed by treatment with 50percent sulphuric acid gives the α,β-unsaturated aldehyde (IV).LAH reduction of IV yields 1-hydroxymethyl-3,3-dimethylcylohex-1-ene (V) which on mercuric acetate catalysed transetherification with ethyl vinyl ether affords the vinyl ether (VI).Claisen rearragement of VI under an inert atmosphere furnishes 2-(6',6'-dimethyl-2'-methylenecylohexyl)ethanal (VII).Aldehyd VII on Wittig reaction with methoxymethylenetriphenylphosphorane provides the ether (VIII) which is readily converted into the ketal (IX) on treatment with ethylene glycol in the presence of catalytic amount of PTS in dry benzene.Deketalisation of IX with PTS in aq. acetone gives the aldehyde (X) which on Grignard reaction with methylmagnesium iodide furnishes 4-(6',6'-dimethyl-2'-methylenecylohexyl)butan-2-ol (XI).Oxidation of XI with pyridinium chlorochromate in anhydrous methylene chloride yields the ketone (XII) which when subjected to Grignard reaction with vinylmagnesium bromide in dry THF provides the vinylic alcohol (XIII).Treatment of XIII with acetic anhydride and glacical acetic acid in the presence of PTS furnishes the allylic acetate (XIV) which on refluxing with methanolic potassium hydroxide in the presence of a little water gives trans-γ-monocyclofarnesol (I).
Cycloaliphatic unsaturated ketones as odour- and taste-modifying agents
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, (2008/06/13)
Process for the preparation of unsaturated cycloaliphatic ketones useful as perfuming and odour-modifying agents in the manufacture of perfumes and perfumed products, and as flavouring and taste-modifying agents in the aromatization of foodstuffs in general and imitation flavours for foodstuffs, beverages, animal feeds, pharmaceutical preparations and tobacco products. Compositions of matter relating to some of said unsaturated cycloaliphatic ketones which are new, and perfume- and flavouring compositions containing same.
