Synthesis, structure, and reactivity of fully aryl-substituted pyrroles: toward the synthesis of nitrogen-doped buckybowls

This study describes the synthesis and potential applications of pentaaryl-substituted pyrroles. We report a Pd-catalyzed approach for their preparation from 4,5-diyne-9-fluorenone (1,7-diyne) and aromatic amines. The target nitrogen-doped corannulenes (CO-hub-Ncor) were investigated computationally to understand their electronic properties. While the conversion of pyrroles to CO-hub-Ncor is underway, the pyrroles themselves hold promise as valuable building blocks for N-doped buckybowls. Additionally, the synthesized pyrrole derivatives exhibit interesting reactivity, including pyrrole oxidation, leading to a ring-opening product, specifically a dicarbonyl compound.

π-Expanded and N-Doped Fluoranthenes

Novel π-expanded and N-doped fluoranthenes were synthesized and thoroughly investigated. These eight unsubstituted compounds are obtained in a multistep synthesis with CH activation as the last key reaction step. The structures vary in their position of π-expansion on the fluoranthene scaffold and the location of the pyridinic nitrogen atom. This facilitates an in-depth investigation of the impact of such alterations in the fluoranthene structure on their overall properties. Accordingly, optical and electrochemical properties of these polyaromatic heterocycles were investigated, and DFT/TD-DFT and NICS calculations were performed. This paper entails a thorough study on b- and l,j-expanded and N-doped fluoranthenes.

Recent Advances in Heterocyclic Nanographenes and Other Polycyclic Heteroaromatic Compounds

This review surveys recent progress in the chemistry of polycyclic heteroaromatic molecules with a focus on structural diversity and synthetic methodology. The article covers literature published during the period of 2016-2020, providing an update to our first review of this topic (Chem. Rev. 2017, 117 (4), 3479-3716).

Domino Cross-Scholl Reaction of Tetracene with Molecular Benzene: Synthesis, Structure, and Mechanism

A domino-type multiple C-H functionalization of tetracene with molecular benzene is reported. Under the typical conditions of the Scholl reaction, a domino reaction occurs between tetracene and six molecules of benzene in one pot to furnish an aromatic compound with a curved π-system. This reaction sequence involves oxidative cross-dehydrogenative coupling/annulation and Friedel-Crafts-type reactions. Eight C-C bonds are formed via this intermolecular domino reaction without mediation by a metal or the assistance of a specific substituent.