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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]

Cyclopentannulation was explored as a strategy to access large, stable azaarenes. Buchwald–Hartwig coupling of previously reported di‐ and tetrabrominated cyclopentannulated N,N′‐dihydrotetraazapentacenes furnished stable azaarenes with up to 13 six‐membered rings in a row and a length of 3.1 nm. Their optoelectronic and semi‐conducting properties as well as their aromaticity were investigated. [ABSTRACT FROM AUTHOR]

Eine Cyclopentanellierungsstrategie wird für den Zugang zu langen, stabilen Azaarenen vorgestellt. Buchwald–Hartwig‐Kupplung von literaturbekannten di‐ und tetrabromierten cyclopentanelierten N,N′‐Dihydrotetraazapentacenen lieferte stabile Azaarene mit bis zu 13 linear anellierten Benzolringen und einer Länge von 3.1 nm. Ihre optoelektronischen und halbleitenden Eigenschaften sowie ihre Aromatizität wurden untersucht. [ABSTRACT FROM AUTHOR]

Brominated pentannulated dihydrotetraazapentacenes were prepared by gold- or palladium-catalyzed 5-endo-dig cyclization of TIPS-ethynylated dihydrotetraazaacenes (TIPS = triisopropylsilyl). Post-functionalization was demonstrated by Sonogashira alkynylation and Rosenmund-von Braun cyanation. Calculations predict these species to act as n-type semiconductors, which was verified for two derivates through characterization in organic field-effect transistors., (© 2022 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

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 cm 2  V -1  s -1 n-channel), which was corroborated by generation of its monoanion and monocation., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The synthesis of novel (N-)acene-based cyclooligomers is reported. Glaser-Hay coupling of the bisethynylated monomers results in cyclodimers and cyclotrimers that are separable by column and gel-permeation chromatographies. For the diazatetracene, the use of sec-butyl-silylethynyl groups is necessary to achieve solubility. Diazatetracene-based cyclodimers and cyclotrimers were used as semiconductors in thin-film transistors. Although their optoelectronic properties are quite similar, their electron mobilities in proof-of-concept thin-film transistors differ by an order of magnitude., (© 2021 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

The syntheses, properties and application of the air-stable electron acceptors, diindenopyrazines 4 a-g are reported demonstrating the introduction of functional aryl groups in the 6- and 12-positions. The targets are accessible on the hundred milligram to gram scale. The structure of the aryl groups in 4 a-g modulates their solubility, redox potentials and optical properties. The introduction of electron-poor aryl groups to the electron-poor diindenopyrazine backbone reduces the electron affinity to -4 eV, making the compounds attractive as n-semiconductors. A simple organic field-effect transistor of 4 e -without optimization- shows electron transport with a mobility of up to 0.037 cm 2  V -1  s -1 ., (© 2021 The Authors. Published by Wiley-VCH GmbH.)