title: 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 π-π stacking involving the diazacarbazole moieties and the phenyl rings of functionalized groups.
authors.affiliation: Structure et Réactivité des Systèmes Moléculaires Complexes (SRSMC), UMR CNRS-UHP 7565 Nancy Université, BP 70239, Bd des Aiguillettes, 54506 Vandoeuvre-les-Nancy, France.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Abboud
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Aubert
authors.forename: Victor
authors.initials: V
authors.lastname: Mamane