Construction of Benzo-Fused Polycyclic Heteroaromatic Compounds through Palladium-Catalyzed Intramolecular C-H/C-H Biaryl Coupling

Dibenzo-fused five-membered heteroaromatic compounds, including dibenzofuran, carbazole, and dibenzothiophene, are fundamental structural units in various important polycyclic heteroaromatic compounds. The intramolecular C-H/C-H biaryl coupling of diaryl (thio)ethers and amines based on palladium(II) catalysis under oxidative conditions is known to be one of the most effective, step-economic methods for their construction. Representative examples for the construction of structurally intriguing π-extended polycyclic heteroaromatics through catalytic coupling reactions are briefly summarized in this mini-review.

Tuning the properties of truxene by successive substitution of nitrogen and sulphur heteroatoms: a DFT insight

In this study, truxene, along with its nitrogen- and sulphur-substituted counterparts were investigated for their properties. The important characteristic properties of a potential conducting material such as HOMO-LUMO gap, electron affinity, ionization potential, and density of states were calculated and compared for analysis. Furthermore, Fukui function and dual descriptor analyses were also carried out, to identify the reactive sites in each of the molecules, as well as understand the effect of substituted heteroatoms. It was seen that the di-substituted candidates were convincingly better fitting for optoelectronic applications.

From truxenes to heterotruxenes: playing with heteroatoms and the symmetry of molecules

As a result of the modification of truxene, we can change the electronic structure or create multidimensional materials. Thus, the use of truxenes is very wide.

Synthesis and circularly polarized luminescence properties of BINOL-derived bisbenzofuro[2,3-b:3',2'-e]pyridines (BBZFPys)

A series of optically active bisbenzofuro[2,3-b:3’,2’-e]pyridine (BBZFPy) derivatives was synthesized starting with the readily available (S)- and (R)-1,1’-bi-2-naphthols through a palladium-catalyzed multiple intramolecular C–H/C–H coupling as the key ring-closure step. The effect of terminal tert-butyl substituents on the BBZFPy skeleton was systematically investigated to uncover a unique aggregation-induced enhancement of CPL characteristics in the solid state. The crystal structures of the coupling products were also evaluated by single crystal X-ray analysis and the well-ordered intermolecular stacking arrangements appeared to be responsible for the enhanced CPL.