34019-86-8Relevant academic research and scientific papers
Pheromone specificity in Eriocrania semipurpurella (Stephens) and E. sangii (Wood) (lepidoptera: eriocraniidae) based on chirality of semiochemicals
Kozlov, Michail V.,Zhu, Junwei,Philipp, Peter,Francke, Wittko,Zvereva, Elena L.,Hansson, Bill S.,Loefstedt, Christer
, p. 431 - 454 (1996)
1966 Plenum Publishing Corporation. The fifth abdominal segment of female Eriocrania semipurpurella (Stephens) and E, sangii (Wood) contains a pair of exocrine glands. Hexane extracts of this segment were prepared from both species and analyzed by gas chromatography with simultaneous flame ionization and electroantennographic detection (EAD). For both species, the EAD active peaks were identified as nonan-2-one, (Z)-6-nonen-2-one, and (Z)-6-nonen-2-ol by means of mass spectrometry and comparison of retention indices with those of synthetic standards. Enantiomeric separation of chiral alcohols from the female extracts was achieved by gas Chromatographic analysis on a cyclodextrin column. In E. semipurpurella, a mixture of (2S,6Z)-nonen-2-ol and (2R,6Z)-nonen-2-ol (2:1) was found, whereas in E. sangii (2S,6Z)-nonen-2-ol was the predominant enantiomer and only traces of the R enantiomer were indicated by the antennal response. In field tests, a blend of the three compounds was not attractive to conspecific males. A subtractive assay showed that the alcohol in various enantiomeric mixtures was the only attractive compound, whereas addition of (Z)-6-nonen-2-one to the alcohol completely inhibited the attraction of both species. A trapping experiment including a wide range of ratios between the R and 5 enantiomers showed that baits containing 95-100% of the S enantiomer were attractive to male E. sangii, whereas males of E, semipurpurella were attracted to all tested ratios of the enantiomers. However, the response profiles of male E. semipurpurella differed between populations from southern Sweden, south Finland, and the Kola Peninsula in Russia. In south Sweden males were maximally attracted to a racemic mixture of the alcohols. At the Kola Peninsula E. semipurpurella was attracted to baits containing 95-100% of the A enantiomer. In south Finland all tested ratios between 0 and 100% R enantiomer trapped E. semipurpurella, but the trap catches appeared to be bimodally distributed with peaks around 15 and 70% R enantiomer. The trapping results suggest the existence of pheromone races or sibling species among the specimens identified as E. semipurpurella.
Synthesis of undecan-3-one; (+/-) frontalin; (+/-)-endo-, and (+/-)-exo-brevicomin under sonochemical aqueous conditions
Trehan, I. R.,Singh, Jasvinder,Arora, Ajay K.,Kaur, Jasamrit,Kad, G. L.
, p. 396 - 398 (2007/10/03)
Conjugate addition of 1-bromohexane (1) to 2-penten-3-one under sonochemical aqueous conditions, using Zn/Cu catalyst give undecan-3-one (3).Also, Zn-Cu catalysed conjugate addition of 1-bromo-2-methylpropene to 3-buten-2-one yield 6-methyl-6-hepten-2-one (6), which is tailored to furnish (+/-)-frontalin (7).Similarly, conjugate addition of 1-bromo-2-pentenes (8 and 8a) to 3-buten-2-one afford Z-6-nonen-2-one (9) and E-6-nonen-2-one (9a) respectively.An ice-cooled solution of 9/9a on tretament with m-chloroperbenzoic acid give (+/-)-exo-(10) and (+/-)-endo-brevicomin (10a) respectively.
Chemoselective conversion of conjugated nitroalkenes into ketones by sodium borohydride-hydrogen peroxide: A new synthesis of 4-oxoalkanoic acids, dihydrojasmone and (±)exo-brevicomin
Ballini,Bosica
, p. 723 - 726 (2007/10/02)
A new, simple, cheap, and practical procedure for the direct transformation of α,β-unsaturated nitroalkenes into ketones has been realized by the NaBH4/H2O2 system. By this method, other functional groups such as C-C double bonds, ketals or aromatic nitro groups were preserved. Application of this methodology to the preparation of 4-oxoalkanoic acids, dihydrojasmone, and (±)-exobrevicomin is also reported.
New and Convenient Synthesis of (Z)-Heneicos-6-en-11-one, the Douglas Fir Tussock Moth (Orgyia pseudotsugata) Sex Pheromone, and (Z)-Non-6-en-2-one, the Immediate Precursor for the Synthesis of Brevicomin, the Sex Attractant of the Western Pine Beetle Dentroctonus brevicomis
Ballini, Roberto
, p. 1419 - 1421 (2007/10/02)
Convenient syntheses of (Z)-heneicos-6-en-11-one and (Z)-non-6-en-2-one were achieved from (Z)-1-nitrodec-4-ene and (Z)-1-nitrohept-4-ene.Solvent-free nitroaldol reaction of (Z)-1-nitro-alkenes 1 with the aldehydes 2 on Amberlyst A-21, followed by in situ oxidation, gave the α-nitro ketones 3.Denitration via p-tolylsulphonylhydrazones and removal of the protecting group gave the title compounds 6a and 6b in 60 and 53 percent overall yield.
SYNTHESIS OF β-SILYL KETONES VIA REACTION OF TRIMETHYLSILYLLITHIUM WITH UNSATURATED HYDRAZONES. APPLICATION TO THE SYNTHESIS OF BREVICOMIN
Hudrlik, Paul F.,Hudrlik, Anne M.,Yimenu, Tilahun,Waugh, Morris A.,Nagendrappa, G.
, p. 3791 - 3804 (2007/10/02)
Trimethylsilyllithium undergoes conjugate addition to dimethylhydrazones of α,β-unsaturated ketones.The resulting metalloenamine intermediates can be alkylated, and the resulting hydrazone products cleaved to give α-substitued-β-silyl ketones.These reacti
Convenient Synthetic Route tp 6,8-Dioxabicyclooctanes, the Aggregation Pheromone Components of Bark Beetles
Joshi, Navalkishore N.,Mamdapur, Vasant R.,Chadha, Mohindra S.
, p. 2963 - 2966 (2007/10/02)
Convenient syntheses of (+/-)-frontalin (I) and (+/-)-brevicomins (IIa) and (IIb) were achieved from pent-4-en-1-ol (2) and pent-4-yn-1-ol (3).In a few simple and unambiguous steps, the alkenol (2) and the alkynol (3) were transformed into the acetal bromide (7) and the alkenyl bromides (14) and (17), respectively.Acylation of Grignard reagents of these bromides provided the corresponding methyl ketones (8), (15), and (18), the key intermediates for the synthesis of the title bicyclic acetals.The ketone (8) was converted into the olefin (9) which, on epoxidation followed by acid hydrolysis, yielded (+/-)-frontalin, whereas epoxidation of the alkenones (15) and (18) and subsequent cyclization afforded exo- and endo-brevicomin, stereoselectively.
