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Pentadien-l-ol

Jung and Nichols have reported a tandem [l,2]-Brook/[l,6]-retro-Brook rearrangement of a l-(trimethylsilyl)-2,4-pentadien-l-ol anion to the aldehyde 181 (equation 112) . Representative examples of [1,5]- and [l,6]-retro-Brook rearrangements are summarized in Table 11. [Pg.814]

Uraneck and Smith (45) recently have described that the product of 2,4-pentadiene-l-ol and sec-butyl-lithium can be used to synthesize polymers with hydroxyl end groups. However, some of the sec-butyl-lithium ( - 137 ) remains unreacted. [Pg.430]

Methyl-2,4-pentadien-l-ol, AH75 3-Methyl-2,4-pentadlenyl acetate, A0O6... [Pg.637]

Uraneck and Smith [125] reported that the product of 2,4-pentadien-l-ol and sec-butyllithium [Eq. (41)] can be used to prepare polymers with terminal hydroxyl groups. [Pg.92]

Using this method, Biichi and Wiiest were able to synthesize a-sinen-sal (27) from rranj-3-methyl-2,4-pentadien-l-ol in an overall yield of 27%.20... [Pg.121]

Optically active C synthons are obtained by stereoselective hydrogenation of methyl-substituted pentadien-l-ols with baker s yeast. They represent useful building blocks for the synthesis of <5- and y-cyclic ethers or lactones37. [Pg.1071]

Different regioselectivities were observed in the reaction of 3,4-pentadien-l-ols 387 with aryl iodides. The expected products 390 and 391 from the tt-allylpalladium intermediates 389 were not formed [151]. Exclusive formation of the dihydrofuran 388 is explained by concerted inter- and intramolecular exo-oxypalladation as shown by 392 to give 7r-allylpalladium 393, and reductive elimination gives rise to the dihydrofuran 394, showing that the intramolecular oxypalladation is faster than the intermolecular carbopalladation with Ar-Pd-I. [Pg.162]

Unusual Pd-catalyzed fragmentation occurred in the reaction of 1-phenyl-2,2-dimethyl-3,4-pentadien-l-ol (395) with iodobenzene. The arylated diene 397 and benzaldehyde were obtained in high yields. In this reaction, phenylpalladium attacked the central carbon to generate the 7r-allylpalladium intermediate 396. Then decarbopalladation ( -carbon elimination) occurred to provide the arylated diene 397 and a-hydroxybenzylpalladium 398, which collapsed to benzaldehyde and Pd(0) [152]. [Pg.162]

Much more favorable results can be obtained with 2-iodoallyl alcohol derivatives. In the syntheses of highly acid-sensitive nakienones and it was not readily feasible to zincate (Z)-2-iodo-2,4-pentadien-l-ol derivatives due to competitive /3-elimination. It was therefore desirable to incorporate the cyclic enone moiety as nucleophiles, as summarized in Scheme 33. [Pg.748]

Methoxy-l,2-nonad1ene, 38 - (22) 3-Methoxy-3,4-pentadien- -l-ol, 39 - (23) 3-Hethoxy-4-ethoxy-l,2-butadiene, 40 - 14) 3-Methoxy--4-ethoxy-l,2-pentadiene, 40 - IS) 1-Triraethylsilyl-l-methoxyallene,... [Pg.145]

An equimolar mixture of 3,4-pentadien-l-ol and pyridine allowed to react with triphenyl phosphite dibromide l-bromo-3,4-pentadiene. Y 76-80%.—Similarly Propargyl alcohol propargyl bromide. Y 72-77%. F. e. s. D. K. Black et al., Tetrah. Let. 1963, 483. [Pg.435]

Thus raM -l,3-pentadiene-Fe(CO)3 fails to react with the triphenyl-methyl fluoroborate under conditions favorable for hydride abstraction in the cyclic series. On the other hand ctf-l,3-pentadiene-iron tricarbonyl (LXXXV) reacts readily under the identical conditions to yield pentadienyl-iron tricarbonyl fluoroborate (LXXXVI) 32). The same cation is obtained from reaction with strong acids (37). Hydrolysis of the cation (LXXXVI) regenerates the alcohol complex while reduction with NaBH4 produces (LXXXV) this latter reaction constitutes the only means to date of making the ar-pentadiene complex (32). These reactions are given in Eq. 14. [Pg.33]


See other pages where Pentadien-l-ol is mentioned: [Pg.39]    [Pg.171]    [Pg.189]    [Pg.677]    [Pg.92]    [Pg.168]    [Pg.93]    [Pg.954]    [Pg.954]    [Pg.403]    [Pg.287]    [Pg.178]    [Pg.24]    [Pg.1236]    [Pg.146]    [Pg.146]    [Pg.146]    [Pg.233]    [Pg.242]    [Pg.674]    [Pg.91]   


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1,4-Pentadiene

2.4- Pentadien

L,4-Pentadien

Pentadienals—

Pentadienes 1,3-pentadiene

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