Categories: C-C Bond Formation > Chains >
Synthesis of 1,4-dienes
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Recent Literature

A microwave synthesis of 1,4-pentadienes has been developed involving the
palladium-catalyzed cross-coupling of potassium vinyltrifluoroborates with
allyl acetates.
G. W. Kabalka, M. Al-Masum, Org. Lett.,
2006,
8, 11-13.

An enhanced Lewis acid system of InCl3 and Me3SiBr can be used to promote a
wide range of direct coupling reactions between alcohols and silyl nucleophiles
in non-halogenated solvents. Highly chemoselective allylations toward a hydroxyl
moiety over ketone and acetoxy ones have been demonstrated.
T. Saito, Y. Nishimoto, M. Yasuda, A. Baba, J. Org. Chem., 2006,
71, 8516-8522.

A mild, cobalt-catalyzed 1,4-hydrovinylation of acyclic 1,3-dienes with
various functionalized terminal alkenes is described. Unsymmetrical
1,3-dienes yield products, where the new carbon-carbon bond is formed at the
less substituted end of the 1,3-diene.
G. Hilt, S. Lüers, Synthesis,
2002, 609-618.

Use of copper(I) tert-butoxide and allylic halides enables the
substitution of the silyl group in vinylsilanes by an allylic group. This
synthetic application of a 1,3 Csp2-to-O silyl migration provides a
useful method for the generation of vinyl anion equivalents.
A. Tsubouchi, M. Itoh, K. Onishi, T. Takeda, Synthesis,
2004, 1504-1508.

On exposure to BuLi, 3-bromo-2-iodocyclopent-2-enol O-TBS ether
undergoes iodine-lithium permutation with complete regioselectivity.
Reaction with different electrophiles affords the corresponding
2-substituted-3-bromocyclopentenol derivatives. Subsequent bromo-lithium
exchange with t-BuLi, followed by reaction with an equal or different
electrophile, affords 2,3-disubstituted cyclopentenols.
M. Luparia, A. Vadalà, G. Zanoni, G. Vidari, Org. Lett.,
2006,
8, 2147-2150.
