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Four substituted nonacenes were prepared and characterized by UV‐vis and EPR spectroscopy and X‐ray crystallography. The compounds are the most stable and soluble nonacenes to date – due to six strategically placed triisopropylsilyl(TIPS)‐ethynyl groups. They are stable for several weeks in the solid state. In dilute solution their half‐life is 5–9 h. Crystal structure analyses of two nonacenes prove their structures. A nonacene derivative was tested in a solution‐processed transistor and exhibits ambipolar charge transport (μe=0.007 cm2/Vs; μh=0.023 cm2/Vs). [ABSTRACT FROM AUTHOR]

The incorporation of heteroatoms into hydrocarbon compounds greatly expands the chemical space of molecular materials. In this context, B−N doping takes a center stage due to its isosterism with a C=C‐bond. Herein, we present a new and modular synthetic concept to access novel diazadiborabenzo[b]triphenylenes 7 a–h using the B−N doped biradical 16 as intermediate. Characterization of the photophysical properties revealed the emission spectra of the diazadibora benzo[b]triphenylenes 7 a–h can conveniently be tuned by small changes of the substitution on the boron‐atom. All of the diazadibora compounds show a short life‐time phosphorescence. Additionally, we were able to rationalize the excited‐state relaxation of the diazadiboraacene 7 a via intersystem crossing by quantum chemical calculations. The new synthetic strategy provides an elegant route to various novel B−N doped acenes with great potential for applications in molecular materials. [ABSTRACT FROM AUTHOR]

Buchwald‐Hartwig coupling of a triisopropylsilyl (TIPS)‐ethynylated dibromo‐N,N'‐dihydrotetraazapentacene with 1,4‐bis(TIPS‐ethynyl)‐2,3‐diaminonaphthalene furnishes a dihydrohexaazaoctacene. Its oxidation with MnO2 results in a 7,7'‐bi(hexaazaoctacenyl). In addition to eight TIPS‐ethynyl groups, the bioctacene motif protects the azaoctacene subunits. The biazaoctacenyl displays a τ1/2 of > 5 d in dilute solution under ambient conditions. In the crystalline state it is persistent for > 10 months. [ABSTRACT FROM AUTHOR]

Sixfold TIPS‐ethynylation combined with fourfold bromination of the armchair edges furnishes a long‐lived, soluble heptacene; π‐extension via Stille coupling accesses a persistent tetrabenzononacene. Both types of acenes were stabilized best by double TIPS‐ethynylation on every other benzene ring. Tetrabromoheptacene is an ambipolar transistor material (up to 0.036 cm2 V−1 s−1 n‐channel), which was corroborated by generation of its monoanion and monocation. [ABSTRACT FROM AUTHOR]