16644-98-7Relevant articles and documents
Preparative singlet oxygenation of linoleate provides doubly allylic dihydroperoxides: Putative intermediates in the generation of biologically active aldehydes in vivo
Zhang, Wujuan,Sun, Mingjiang,Salomon, Robert G.
, p. 5607 - 5615 (2006)
Photoinduced oxygenation generates biologically active, oxidatively truncated lipids in the retina. Previously, doubly allylic dihydroperoxides, 9,12-dihydroperoxyoctadeca-10,13-dienoic acid (9,12-diHPODE) and 10,13-dihydroperoxyoctadeca-8,11-dienoic acid (10,13-diHPODE), were postulated as key intermediates in the free radical-promoted oxidative fragmentation of linoleate that generates aldehydes, such as the cytotoxic γ-hydroxyalkenal 4-hydroxy-2-nonenal (HNE), in vivo. We now report an efficient preparation of regioisomerically pure 9,12- and 10,13-diHPODE, devised to enable studies of their fragmentation reactions. Free radical-induced oxygenation of linoleate initially generates conjugated monohydroperoxy octadecadienoates (HPODEs) that are then converted into diHPODEs. In contrast, we found that singlet oxygenation of conjugated HPODEs does not produce diHPODEs. Unconjugated HPODEs are unique products of singlet oxygenation of linoleate that are coproduced with conjugated HPODEs. Preparative separation of the mixture of regioisomeric mono and diHPODEs generated by singlet oxygenation of linloeate is impractical. However, a simple tactic circumvented the problem. Thus, selective conversion of the undesired conjugated HPODEs into Diels-Alder adducts could be accomplished under mild conditions by reaction with N-phenyltriazolinedione. These adducts were readily removed, and the two remaining unconjugated HPODEs could then be easily isolated regioisomerically pure. Each of these was subsequently converted into a different, regioisomerically pure, diHPODE through further singlet oxygenation.
Chemical characterization and synthesis of the major component of the sex pheromone of the sugarcane borer Diatraea saccharalis
Svatos, Ales,Kalinova, Blanka,Kindl, Jiri,Kuldova, Jelena,Hovorka, Oldrich,Do Nascimento, Ruth Rufino,Oldham, Neil J.
, p. 1682 - 1690 (2001)
(9Z,11E)-Hexadeca-9,11-dienal (1) was identified as a major component of the sex pheromone of the sugarcane borer Diatraea saccharalis. The identification is based on mass spectral examination of the extracts prepared from calling females, derivatization experiments with 4-methyl-3,5-dihydro-1,2,4-triazole-3,5-dione (2), stereospecific synthesis of dienal 1, and gas chromatography (GC) with electroantennographic detection (GC-EAD). In GC analysis, the antennaly active component and synthetic dienal 1 show identical retention times on several GC phases. However, the behavioral activity of synthetic 1 was much weaker than that of natural extracts. This suggests that an additional component(s) might be involved in sexual communication of this species.
Total Synthesis of Natural Bicyclic Lactones (+)-Dihydrocanadensolide, (±)-Avenociolide, and (±)-Isoavenociolide via Tungsten-π-Allyl Complexes
Chen, Ming-Jung,Narkunan, Kesavaram,Liu, Rai-Shung
, p. 8311 - 8318 (1999)
A synthetic method using tungsten-π-allyl compounds is developed for total syntheses of natural bislactones including (+)-dihydrocanadensaolide (2), (±)-avenociolide (3), and (±)-isoavenociolide (4). Syntheses of these natural compounds are based on a com
STEREOSPECIFIC SYNTHESIS OF (Z)-13-HEXADECEN-11-YN-1-YL ACETATE THE SEX PHEROMONE OF THE PROCESSIONARY MOTH, AND OF (5Z,7E)-5,7-DODECADIEN-1-OL, A SEX PHEROMONE COMPONENT OF THE FOREST TENT CATERPILLAR
Rossi, Renzo,Carpita, Adriano
, p. 287 - 290 (1983)
(Z)-13-hexadecen-11-yn-1-yl acetate (2), the sex pheromone of Thaumetopoea pytyocampa, and (5Z,7E)-5,7-dodecadien-1-ol (3), sex pheromone component of Malacosoma disstria, have been prepared in high chemical and stereoisomeric purity by synthetic schemes involving the stereospecific coupling of ω-functionalized 1-alkynes with (Z)- or (E)-1-iodo-1-alkenes in the presence of a catalytic amount of (PPh3)4Pd and CuI, under phase transfer conditions.
Hydroboration. 55. Hydroboration of Alkynes with Dibromoborane-Dimethyl Sulfide. Convenient Preparation of Alkenyldibromoboranes
Brown, Herbert C.,Campbell, James B.
, p. 389 - 395 (1980)
Dibromoborane-dimethyl sulfide undergoes direct hydroboration of both terminal and internal alkynes with remarkable facility to give alkenyldibromoboranes.These reactive alkenylboranes, which may be isolated, undergo many synthetically useful transformations.Oxidation provides the carbonyl compounds, while protonolysis with acetic acid occurs stereospecifically to yield the corresponding alkenes. 1-Alkenyldibromoboranes can be converted easily to 1-iodo-1-alkenes by basic hydrolysis and iodination.Both internal and 1-alkenyldibromoboranes serve as convenient precursors to symmetrical conjugated dienes by reaction with 3 equiv of methylcopper.Hydroboration of alkynes with HBBr2*SMe2 is critically examined in terms of relative reactivities of both alkyne and alkene substrates.A very broad reactivity spectrum is evident, with internal acetylenes reacting with remarkable facility.The regiospecifity of the hydroboration of unsymmetrically substituted alkynes indicates HBBr2*SMe2 to be a highly selective reagent, sensitive to both steric and electronic effects.The regioselectivity is compared with that of other hindered hydroborating reagents, such as 9-BBN and disiamylborane.
Stereoselective Csp3?Csp2 Cross-Couplings of Chiral Secondary Alkylzinc Reagents with Alkenyl and Aryl Halides
Skotnitzki, Juri,Kremsmair, Alexander,Keefer, Daniel,Gong, Ye,de Vivie-Riedle, Regina,Knochel, Paul
supporting information, p. 320 - 324 (2019/11/26)
We report palladium-catalyzed cross-coupling reactions of chiral secondary non-stabilized dialkylzinc reagents, prepared from readily available chiral secondary alkyl iodides, with alkenyl and aryl halides. This method provides α-chiral alkenes and arenes with very high retention of configuration (dr up to 98:2) and satisfactory overall yields (up to 76 % for 3 reaction steps). The configurational stability of these chiral non-stabilized dialkylzinc reagents was determined and exceeded several hours at 25 °C. DFT calculations were performed to rationalize the stereoretention during the catalytic cycle. Furthermore, the cross-coupling reaction was applied in an efficient total synthesis of the sesquiterpenes (S)- and (R)-curcumene with control of the absolute stereochemistry.
Oxidative Addition of Alkenyl and Alkynyl Iodides to a AuI Complex
Bower, John F.,Cadge, Jamie A.,Russell, Christopher A.,Sparkes, Hazel A.
supporting information, p. 6617 - 6621 (2020/03/13)
The first isolated examples of intermolecular oxidative addition of alkenyl and alkynyl iodides to AuI are reported. Using a 5,5′-difluoro-2,2′-bipyridyl ligated complex, oxidative addition of geometrically defined alkenyl iodides occurs readily, reversibly and stereospecifically to give alkenyl-AuIII complexes. Conversely, reversible alkynyl iodide oxidative addition generates bimetallic complexes containing both AuIII and AuI centers. Stoichiometric studies show that both new initiation modes can form the basis for the development of C?C bond forming cross-couplings.
One-Shot Radical Cross Coupling Between Benzyl Alcohols and Alkenyl Halides Using Ni/Ti/Mn System
Suga, Takuya,Takahashi, Yuuki,Ukaji, Yutaka
supporting information, p. 5622 - 5626 (2020/10/22)
A “one-shot” cross coupling between benzyl alcohols and alkenyl halides has been established. A combination of low-valent Ti-mediated C?OH homolysis and the prominent chemistry of Ni-based radical catalysis afforded the desired cross-coupled product with good efficiency. The reaction proceeded regardless of the electronic property of benzyl alcohols, and Ar?B bond remained intact throughout the reaction. Alkenyl bromides with various substitution patterns were applicable to this reaction. Attempts for utilizing sterically demanding tri-substituted alkenes indicated that the steric hinderance mainly inhibited the radical-trapping by Ni species. This reaction can be a simple and efficient strategy for synthesizing densely substituted allylbenzene derivatives. (Figure presented.).
First total synthesis of Debilisone C
Saikia, Bishwajit,Joymati Devi, Thongam,Barua, Nabin C.
, p. 905 - 913 (2013/03/14)
Total synthesis of Debilisone C, a lactone containing conjugated endiyne has been achieved. The adopted strategy involves the stereoselective construction of the five membered lactone ring and the C20 endiyne chain followed by regioselective coupling of both the parts. The lactone was obtained from the oxidative cleavage of the hydroxy olefin which was derived from the benzyl protected S-epichlorohydrine by regioselective epoxide opening with allyl trimethyl silane in presence of a Lewis acid at -78 °C. Takai olefination, Pd0/Ag1 catalyzed cross-coupling reaction and selective substitution of trimethylsilyl groups were successfully utilized to establish the C20 polyyne chain. The final coupling of both the parts have been carried out by alkyl coupling using LDA in THF-DMPU (1 : 1).
Reactions of perfluorinated alkenyl-, alkynyl-, alkyltrifluoroborates, and selected hydrocarbon analogues with the halogenating agents Hal2 (Hal = F, Cl, Br), "brF" (BrF3-Br2 1:1), and ICl
Bardin, Vadim V.,Adonin, Nicolay Yu.,Frohn, Hermann-Josef
experimental part, p. 565 - 579 (2012/05/20)
Reactions of [Bu4N][RBF3] [R = CnF 2n+1CF=CF (cis, trans), CF2=CF, CF2=C(CF 3), trans-C4H9CF=CF, trans-C6H 5CF=CF, C4H9CH=CH (cis, trans), CF 3C≡C, and C4H9C≡C] with chlorine, bromine, BrF3 + Br2 (as equivalent of "BrF"), and ICl in solution (CH2Cl2, CHCl3, CF 3CH2CF2CH3) led to 1, 2-addition of halogen and/or replacement of boron by halogen (halodeboration). The reaction of [Bu4N][CF3C≡CBF3] with less than equimolar amounts of diluted fluorine (5 %) in 1, 1, 1, 3, 3-pentafluorobutane (PFB) showed only [Bu4N][CF3CF2CF 2BF3] as fluorine addition product besides extensive fluorodeboration. Suspensions of the insoluble K[CF2=CFBF 3] salt reacted with Cl2 and Br2 in CH 2Cl2 giving preferentially products of halogen addition across the C=C bond. In reactions with ICl iododeboration with formation of CF2=CFI occurred besides 1, 2-addition with formation of [CF 2I-CFClBF3]-. The halodeboration reaction of[Bu4N][trans-C4H9CF=CFBF3] with Br2, "BrF", and ICl, of K[trans-C6H 5CF=CFBF3] with Br2, and of [Bu 4N][trans-C4F9CF=CFBF3] with ICl proceeded stereospecifically. Copyright
