Tribenzoazaasepentalenit anyonu: Olağandışı düzlemsel aromatik bileşiğin keşfi̇

With the discovery of fullerenes, the interest in synthesis of non-planar aromatic compounds increased significantly and these types of materials became important targets among the synthetic chemistry community. The dihydroacepentalenediide, the dianion of acepentalene was one of the widely sought targets which was synthesized in 1986 starting from triquinacene. Triquinacene itself also attracted significant attention due being potential precursor of dodecahedrane and possible homoaromaticity it might possess. Although many derivatives of triquinacene structure has been synthesized, hetero-analogues of the compound did not get attention until much later. The Mascal group was the first to realize the synthesis of nitrogen and oxygen containing derivatives where both showed remarkable structural properties and reactivities. The tribenzotriquinacene was also widely examined similar to triquinacene and many derivatives were realized over the years. Yet its heteroanalogues have never been studied. This study describes our efforts for nitrogen analogue, tribenzoazatriquinacene and its aromatic anion tribenzoazaacepentalenide. Tribenzoazatriquinacene was successfully synthesized starting from commercially available 5-dibenzosuberenone in 8 steps, including a remarkable cascade of cyclization/hydrogenation reaction. The existence of the corresponding 22 aromatic anion, tribenzoazaacepentalenide, was also successfully shown via a low-temperature NMR experiment.