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Double N-arylation reaction of polyhalogenated 4,4'-bipyridines. Expedious synthesis of functionalized 2,7-diazacarbazoles.

ABSTRACT: Unusual 2,7-diazacarbazoles were prepared in one step from readily available tetra-halogenated 4,4'-bipyridines by using a double N-arylation reaction in the presence of the Pd-XPhos catalyst system. Moderate to good yields were obtained in this site-selective Buchwald-Hartwig double amination. The functionalization of these tricyclic derivatives was performed by using Pd-catalyzed cross-coupling reactions such as the Stille and Suzuki couplings. Two compounds were analyzed by X-ray diffraction and show ?-? stacking involving the diazacarbazole moieties and the phenyl rings of functionalized groups.

SUBMITTER: Abboud M

PROVIDER: S-EPMC3302087 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Double N-arylation reaction of polyhalogenated 4,4'-bipyridines. Expedious synthesis of functionalized 2,7-diazacarbazoles.

Abboud Mohamed M Aubert Emmanuel E Mamane Victor V

Beilstein journal of organic chemistry 20120214

Unusual 2,7-diazacarbazoles were prepared in one step from readily available tetra-halogenated 4,4'-bipyridines by using a double N-arylation reaction in the presence of the Pd-XPhos catalyst system. Moderate to good yields were obtained in this site-selective Buchwald-Hartwig double amination. The functionalization of these tricyclic derivatives was performed by using Pd-catalyzed cross-coupling reactions such as the Stille and Suzuki couplings. Two compounds were analyzed by X-ray diffraction ...[more]

PMID: 22423292

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