Pyridine-borane complexes were synthesized from 2-arylpyridines through an electrophilic aromatic borylation reaction with BBr(3). The intermediate 2-(2-dibromoborylaryl)pyridines were stable enough to be handled in air and served as the synthetic platform for variously substituted pyridine-borane complexes. This facile method would be useful for the synthesis of aza-π-conjugated materials having boron-nitrogen coordination.

[reaction: see text] Silicon-bridged 1,6-diynes underwent [2 + 2 + 2] cycloaddition with alkynes in the presence of an iridium(I)-phosphine catalyst to afford densely substituted silafluorene derivatives. Extended silafluorene skeletons were constructed by the [2 + 2 + 2] cycloaddition of tetraynes.

The palladium-catalyzed intramolecular oxidative C-H/C-H coupling of 2-aryloxypyridines as challenging substrates is investigated to construct an important class of N,O-mixed heteroacenes, i.e. benzofuropyridines. It is found that 2,6-diaryloxypyridines efficiently undergo double cyclization to provide bisbenzofuro[2,3-b:3',2'-e]pyridines of interest in materials chemistry.

From six to seven: 2,2′‐Di(arylethynyl)biphenyls undergo a skeletal rearrangement in the presence of a platinum(II) catalyst to afford polycyclic aromatic compounds containing an azulene unit. The reaction involves CC bond cleavage of a benzene ring, which expands into a seven‐membered ring.

Cationic gold(I) complexes having Buchwald-type biarylphosphines effectively catalyzed twofold hydroarylation of 2,6-dialkynylbiphenyls to construct pyrene skeletons.

Exploring the design principle for switching thermally activated delayed fluorescence (TADF) and room temperature phosphorescence (RTP) is a fundamentally imporant research in developing triplet-mediated photofunctional organic materials. Herein systematic studies...

A new family of thermally activated delayed fluorescence (TADF) emitters based on a twisted donoracceptor (DÀ A) dyad scaffold comprising of dihydrophenazasiline (D) and pyrido[2,3-b]pyrazine (A) has been developed, and their properties have been investigated. Time-resolved spectroscopic analysis in matrices revealed the detailed photophysical properties of the DÀ A compounds. These DÀ A compounds serve as the emitter for organic light-emitting diodes (OLEDs), showing a moderate external quantum efficiency (EQE) up to 9% in CBP matrix. Furthermore, theoretical calculations uncovered the excited states nature of the developed TADF emitters.

No abstract