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Highly efficient and selective synthesis of conjugated triynes and higher oligoynes of biological and materials chemical interest via palladium-catalyzed alkynyl-alkenyl coupling.

ABSTRACT: Iteration of a Pd-catalyzed reaction of alkynyl- and oligoynylzincs with (E)-ICH=CHCl followed by metalation-termination with electrophiles(E) has provided a linear route to conjugated tri- and tetraynes, and Pd-catalyzed monoalkynylation of 1,1-dibromoenynes accompanied by dehydrobromination has provided a convergent route to conjugated tri- , tetra- , and pentaynes. Both display unprecedented high efficiency and selectivity. [reaction: see text]

SUBMITTER: Metay E

PROVIDER: S-EPMC3891648 | biostudies-literature | 2006 Dec

REPOSITORIES: biostudies-literature

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Highly efficient and selective synthesis of conjugated triynes and higher oligoynes of biological and materials chemical interest via palladium-catalyzed alkynyl-alkenyl coupling.

Métay Estelle E Hu Qian Q Negishi Ei-ichi E

Organic letters 20061201 25

Iteration of a Pd-catalyzed reaction of alkynyl- and oligoynylzincs with (E)-ICH=CHCl followed by metalation-termination with electrophiles(E) has provided a linear route to conjugated tri- and tetraynes, and Pd-catalyzed monoalkynylation of 1,1-dibromoenynes accompanied by dehydrobromination has provided a convergent route to conjugated tri- , tetra- , and pentaynes. Both display unprecedented high efficiency and selectivity. [reaction: see text] ...[more]

PMID: 17134269

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