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Aromatic compounds containing triazenyl groups (N3RR′) have a profound impact on synthetic organic and medicinal chemistry. In contrast, the chemistry of vinyl and alkynyl triazenes was a largely uncharted territory until recently. The situation has changed over the last five years, and it has become apparent that vinyl and alkynyl triazenes are highly interesting compounds with a unique reactivity. The electron‐donating properties of the triazenyl group provide alkynyl triazenes with an ynamide‐like reactivity, which can be exploited in reactions of the triple bond. Vinyl triazenes, on the other hand, can be used for electrophilic vinylation reactions. The foundation for this new triazene chemistry are synthetic pathways which allow preparing vinyl and alkynyl triazenes in few steps from readily available starting materials. In this Minireview, we summarize recent developments in this area. [ABSTRACT FROM AUTHOR]

Tetraarylethenes are obtained by acid‐induced coupling of vinyl triazenes with aromatic compounds. This new C−H activation route for the synthesis of aggregation‐induced emission luminogens is simple, fast, and versatile. It allows the direct grafting of triarylethenyl groups onto a variety of aromatic compounds, including heterocycles, supramolecular hosts, biologically relevant molecules, and commercial polymers. [ABSTRACT FROM AUTHOR]

Highly substituted Δ3‐1,2,3‐triazolines can be prepared by reaction of triarylvinyl Grignard reagents with functionalized organic azides. The heterocycles are fluorescent in the solid state, and—depending on the substituents—they can display aggregation‐induced emission. Upon oxidation, the triazolines form stable radical cations with altered photophysical properties. Therefore, they represent rare examples of solid‐state emitters with intrinsic electrofluorochromic behavior. [ABSTRACT FROM AUTHOR]

Dichalcogenolenes are archetypal redox non-innocent ligands with numerous applications. Herein, a diselenolene ligand with fundamentally different electronic properties is described. A mesoionic diselenolene was prepared by selenation of a C2-protected imidazolium salt. This ligand is diamagnetic, which is in contrast to the paramagnetic nature of standard dichalcogenolene monoanions. The new ligand is also redox-active, as demonstrated by isolation of a stable diselenolene radical dianion. The unique electronic properties of the new ligand give rise to unusual coordination chemistry. Thus, preparation of a hexacoordinate aluminum tris(diselenolene) complex and a Lewis acidic aluminate complex with two ligand-centered unpaired electrons was achieved., (© 2022 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

Borylated triazenes were synthesized by the dehydrocoupling of triazenes with 9-borabicyclo(3.3.1)nonane, by the condensation of triazenes with BEt 3 , or by the reaction of sodium triazenides with dialkyl- or diarylboron halides. The structures of the products were found to depend on the size of the substituents. Sterically demanding mesityl groups at boron or nitrogen gave rise to open-chain structures, whereas smaller substituents led to the formation of novel BN 3 heterocycles.

Tetraarylethenes are obtained by acid-induced coupling of vinyl triazenes with aromatic compounds. This new C-H activation route for the synthesis of aggregation-induced emission luminogens is simple, fast, and versatile. It allows the direct grafting of triarylethenyl groups onto a variety of aromatic compounds, including heterocycles, supramolecular hosts, biologically relevant molecules, and commercial polymers., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Highly substituted Δ 3 -1,2,3-triazolines can be prepared by reaction of triarylvinyl Grignard reagents with functionalized organic azides. The heterocycles are fluorescent in the solid state, and-depending on the substituents-they can display aggregation-induced emission. Upon oxidation, the triazolines form stable radical cations with altered photophysical properties. Therefore, they represent rare examples of solid-state emitters with intrinsic electrofluorochromic behavior., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Vinyl triazenes were obtained by enantioselective [2+2] cycloaddition reactions of bicyclic alkenes with 1-alkynyl triazenes in the presence of a Ru II catalyst with a chiral cyclopentadienyl ligand. These triazenes serve as unique vinyl cation surrogates. Under acidic conditions, the triazene functionality can be replaced with a variety of groups, including halides, alkoxides, sulfoxides, amides, arenes, and heteroarenes, thus providing efficient access to a pool of chiral polycyclic compounds., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)