2630-39-9Relevant academic research and scientific papers
Further explorations into the synthesis of Dehydro-Hedione
Winter, Béat,Chapuis, Christian,Brauchli, Robert,De Saint Laumer, Jean-Yves
, p. 246 - 258 (2013/03/28)
Dehydrohedione (DHH) 1 may be obtained in 20% overall yield by a Reformatsky reaction with enone methyl ether 3b, followed by acidic workup of the crude reaction mixture. Alternatively, epoxidation (3-chloroperbenzoic acid, CH2Cl2, 84% yield) of the tertiary allyl alcohol derivative 4 affords a 1: 2 mixture of 8a and 8b. The latter epoxy ester 8b may also be obtained stereoselectively either from 4 (tBuO2H, [Mo(CO)6], 1,2-dichloroethane, 70°, 62% yield; or tBuO2H, [VO(acac)2], decane, 20°, 92% yield), or from 5 (AcOMe, LiN(SiMe3)2, THF, -78°, 84-87%). BF3×Et2O-Catalyzed cascade rearrangement and OH elimination of 8a afford selectively DHH 1 in 88% yield. The cis disposition of the side chains of the weakly odoriferous hedione-like analogues 2b and 2c was maintained by means of either an epoxy or a cyclopropane moiety. Copyright
Identification of novel decenoic acids in heated butter
Ito, Nobuhiko,Wada, Shigeru,Yamanaka, Yousuke,Takagaki, Hitoshi,Nakamura, Hironori
, p. 2416 - 2420 (2008/02/03)
Novel decenoic acids such as (E)-4-decenoic acid and (E)- and (Z)-5-,6-decenoic acid were detected as minor components in heated butter using GC and GC/MS. The formation mechanism of these novel decenoic acids is discussed on the basis of the result of the reaction of δ-decalactone with active clay in a model experiment.
Synthesis of (±)-methyl epijasmonate and (±)-methyl dihydroepijasmonate by diastereoselective protonation
Krause, Norbert,Ebert, Sophia
, p. 3837 - 3841 (2007/10/03)
The synthesis of (±)-methyl epijasmonate (1) was carried out by Michael addition of lithium diallylcuprate to enone 3 and diastereoselective enolate protonation with the chelating proton source 2-(methyliminomethyl)phenol (4; 85% ds), followed by ozonolysis, oxidation, esterification, and Lindlar hydrogenation. During the ozonisation, epimerization to the thermodynamically more stable trans-isomer takes place to some extent, so that 1 was isolated with a cis:trans ratio of 72:28. The analogous transformation of enone 7 with lithium diallylcuprate and 2-(methyliminomethyl)phenol (4) furnished ketone 8 with 94% ds; this was then transformed into (±)-methyl dihydroepijasmonate (2) with a cis:trans ratio of 91:9. The olfactory properties of this product are superior to those available from commercial sources.
1,4-Addition of chiral 2-propenylphosphonamide anions to α-substituted cyclopentenones: Use in enantioselective syntheses of methyl dihydrojasmonates and methyl jasmonates
Hailes, Helen C.,Isaac, Ben,Javaid
, p. 7325 - 7328 (2007/10/03)
The addition of chiral 2-propenylphosphonamide anions, generated from the reaction products of (1R,2S)-ephedrine and 2-propene-1-phosphonyl dichloride, to α-substituted cyclopentenones is described. Ozonolysis of the addition products led to the synthesis of both enantiomers of methyl dihydrojasmonate and methyl jasmonate.
A new variant of the Claisen rearrangement from malonate-derived allylic trimethylsilyl ketene acetals: Efficient, highly enantio- and diastereoselective syntheses of (+)-methyl dihydroepijasmonate and (+)-methyl epijasmonate
Fehr, Charles,Galindo, Jose
, p. 569 - 573 (2007/10/03)
Complete chirality transfer occurs in the smooth Claisen rearrangement of the trimethylsilyl (TMS) ketene acetals, which were prepared from allylic malonates (R)-1 (R = pentyl, 2-(Z)-pentenyl). These are in turn accessible by enantioselective reduction/esterification or by enzymatic kinetic resolution. The cis configuration in (+)-3 was achieved by highly syn-selective epoxidation of (+)-2, followed by suprafacial 1,2-H migration.
Enantioselective synthesis of both enantiomers of methyl dihydrojasmonate using solid-liquid asymmetric phase-transfer catalysis
Perrard, Thierry,Plaquevent, Jean-Christophe,Desmurs, Jean-Roger,Hebrault, Dominique
, p. 2959 - 2962 (2007/10/03)
Both enantiomers of methyl dihydrojasmonate (-)-1 and (+)-1 were obtained by a short route using asymmetric Michael addition of dimethyl malonate onto pentyl enone 3, followed by nonracemizing demethoxycarbonylation. The key enantioselective step involves a new system of asymmetric solid - liquid phase-transfer catalysis using solvent-free conditions. Enantiomeric excess as high as 90% (91% yield) was achieved.
CYCLOPENTANE FATTY ACIDS FROM GIBBERELLA FUJIKUROI
Miersch, Otto,Brueckner, Bettina,Schmidt, Juergen,Sembdner, Guenther
, p. 3835 - 3838 (2007/10/02)
Several mutants of the fungus Gibberella fujikuroi were shown to produce cyclopentane fatty acids of the jasmonic acid type.Detailed investigation of the culture filtrate of one mutant resulted in the isolation and structural elucidation of (+)-7-iso-jasmonic acid and (-)-jasmonic acid as well as their (S)-isoleucine conjugates and 4,5-didehydro-9,10-dihydrojasmonic acid.Out of nine further mutants studied, all of them produced the two isoleucine conjugates but in only four of them could free jasmonic acid be detected (max amount of 2.5 mg l-1). Key Word Index: Gibberella fujikuroi; Fusarium moniliforme; (+)-7-iso-jasmonic acid; (-)-jasmonic acid; 4,5-didehydro-9,10-dihydrojasmonic acid; N--(S)-isoleucine.
Synthesis of 12-Oxophytodienoic Acid (12-OxoPDA) and the Compounds of its Enzymic Degradation Cascade in Plants, OPC-8:0, -6:0, -4:0 and -2:0 (epi-Jasmonic Acid), as their Methyl Esters
Crombie, Leslie,Mistry, Kamlesh M.
, p. 1981 - 1991 (2007/10/02)
The synthesis of 12-Oxophytodienoic acid, and the compounds of its enzymatic degradation sequence, OPC-8:0, -6:0, -4:0 and -2:0, important plant metabolites derived from linolenic acid, is reported.The syntheses use the known cyclopent-3-ene-1,2-diacetic acid as an early intermediate, and this is derived from the Cope rearrangement of 5-vinyltrinorborn-2-ene via bicyclonona-3,7-diene.Iodolactonisation and tributyltin hydride reduction provides the key intermediate (3-oxo-2-oxabicyclooctan-6-yl)acetic acid for the OPC series, whilstphenylselenolactonisation and elimination provides the necessary unsaturated lactone (7-oxo-8-oxabicyclooct-2-en-4-yl)acetic acid for 12-oxoPDA.Members of the OPC-series were made by chain extending the saturated oxabicyclooctane acid: that for the OPC-4:0 involved double Arndt-Eistert reaction, whilst the intermediates for OPC-6:0 and -8:0 were made by Kolbe anodic crossed coupling.The lactones were than converted via their lactols, Wittig reaction, esterfication and oxidation, into the compounds of the OPC ester series, including OPC-2:0 (methyl epi-jasmonate).The unsaturate lactone 8-(7-oxo-8-oxabicyclooct-2-en-4-yl)octanoic acid required for 12-oxoPDA synthesis could also be prepared by anodic synthesis either from (7-oxo-8-oxa-bicyclooct-2-en-4-yl)acetic acid, or from its 2-phenylseleno-2,3-dihydro precursor as elimination occurred concomitantly during the reaction.Since yields were low, the unsaturated acid lactone was converted into its lactol and the (Z)-pent-2-enyl side-chain was inserted first.After TBDMS blocking of the cyclopentene hydroxy group, the side-chain was elaborated to give5-(pent-2-enyl)cyclopent-2-enylacetaldehyde and chain extension carried out by a Grignard-demesylation procedure.Sequential desilylation and depyranylation, followed by oxidation of the diol, gave 12-oxoPDA, isolated as its methyl ester.
ELECTROREDUCTIVE INTRAMOLECULAR COUPLING OF γ- AND δ-CYANOKETONES
Shono, Tatsuya,Kise, Naoki
, p. 1303 - 1306 (2007/10/02)
Electroreduction of γ- and δ-cyanoketones in i-PrOH gave cyclized products α-hydroxyketones and their dehydroxylated ketones, and this reaction was applied to the synthesis of dihydrojasmone, methyl dihydrojasmonate, and Rosaprostol.
JASMONIC ACID-LIKE SUBSTANCES FROM THE CULTURE FILTRATE OF BOTRYODIPLODIA THEOBROMAE
Miersch, Otto,Schmidt, Juergen,Sembdner, Guenther,Schreiber, Klaus
, p. 1303 - 1306 (2007/10/02)
Four cyclopentanoidal fatty acids were isolated from the fungus Botryodiplodia theobromae and identified as jasmonic acid-like substances.Their structures are (+)-4,5-didehydro-7-iso-jasmonic acid , ethyl (+)-7-iso-jasmonate , (1R,2S)-(+)-3-oxo-2-(2Z-pentenyl)cyclopent-1-yl-propionic acid and (1S,2S)-3-oxo-2-(2Z-pentenyl)cyclopent-1-yl-butyric acid. - Keywords: Botryodiplodia theobromae; Sphaeropsidaceae; (+)-4,5-didehydro-7-iso-jasmonic acid; ethyl (+)-7-iso-jasmonate; (1R,2S)-(+)-3-oxo-2-(2Z-pentenyl)cyclopent-1-yl-propionic acid; (1S,2S)-(+)-3-oxo-2-(2Z-pentenyl)cyclopent-1-yl-butyric acid.
