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Dienic acid

In addition to these extensive studies on electrophile-mediated intramolecular peroxydation of electron-rich C=C bonds, some examples of intramolecular hydroperoxide addition to electron-poor C=C bonds have been described. For example, several racemic analogues 371 of the naturally occurring plakinic acid were readily obtained by peroxymercuration followed by hydridodemercuration of the dienic acids 370 (Scheme 95 f °. Intramolecular Michael addition of hydroperoxide function to the double... [Pg.242]

Mestres et al. [40] published a regioselective addition of a lithium trienediolate (generated from hexa-2,4-dienoic acid or dihydropyran-2-one) to p-ionone. Dehydration of the hydroxyacid, afforded a mixture of 9E/Z, 13E/Z retinoic acids which, isomerised in the presence of I2, led to all E retinoic acid in 35% and 30% yield, starting from dienic acid and pyranone, respectively, Fig. (16). [Pg.79]

Pappo, Bloom, and Johnson effected acetylation of the 3/3-hydroxyl group of the steroid dienic acid (1) by ester interchange with excess phenyl acetate in the presence of sodium hydride. Conventional acetylation is complicated by the formation of a mixed anhydride and the necessity for a step of selective hydrolysis. [Pg.1148]

Canevet, J.C., and Sharrard, E, Synthesis of cyclic enones and dienic acids by Wittig-Homer-Emmons reaction. Tetrahedron Lett., 23, 181, 1982. [Pg.321]

Antheridiol.—The structure determination of antheridiol (100), the first specifically functioning steroidal sex hormone to be found in the plant kingdom which, when secreted by the female mycelia of the aquatic fungus Achlya bisexualis, initiates sexual reproduction, has been rapidly followed by its synthesis. Aldol condensation of ethyl 3,4-dimethylpent-2-enoate with the aldehyde (96) produced the unsaturated lactone (98) which could be op>ened to the dienic acid (99) with... [Pg.420]

Andreev, V.G. Kolomiets, A.F. Fokin, A.V. Synthesis and properties of 2-trifluoromethyl-substituted pent-4-en-, pent-3,4-dienic acids and their esters. Izv. Akad. Nauk SSSR, Ser. Khim. 1991, 12, 2805-2809. [Pg.218]

The product of Ireland-Claisen rearrangement of a propargylic ester is a penta-3,4-dienic acid. In contrast to rearrangements of allyic esters, there has been considerably less work on propargylic esters [141]. [Pg.201]

For the synthesis of (+)-desoxynq irimycin starting with an AD of a dienic acid ester see Lindstroem, U. M. Somfai, P. Tetrahedron Lett. 1998,39,7173. [Pg.427]


See other pages where Dienic acid is mentioned: [Pg.239]    [Pg.240]    [Pg.81]    [Pg.501]    [Pg.427]    [Pg.371]    [Pg.410]    [Pg.207]    [Pg.196]    [Pg.31]    [Pg.32]    [Pg.17]    [Pg.600]    [Pg.336]   
See also in sourсe #XX -- [ Pg.387 ]




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