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Multimetallic Ni- and Pd-Catalyzed Cross-Electrophile Coupling To Form Highly Substituted 1,3-Dienes.

ABSTRACT: The synthesis of highly substituted 1,3-dienes from the coupling of vinyl bromides with vinyl triflates is reported for the first time. The coupling is catalyzed by a combination of (5,5'-bis(trifluoromethyl)-2,2'-bipyridine)NiBr2 and (1,3-bis(diphenylphosphino)propane)PdCl2 in the presence of a zinc reductant. This method affords tetra- and penta-substituted 1,3-dienes that would otherwise be difficult to access and tolerates electron-rich and -poor substituents, heterocycles, an aryl bromide, and a pinacol boronate ester. Mechanistically, the reaction appears to proceed by an unusual zinc-mediated transfer of a vinyl group between the nickel and palladium centers.

SUBMITTER: Olivares AM

PROVIDER: S-EPMC5821523 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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