Diindenopyrazines: Electron‐Deficient Arenes

Abstract

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 cm2 V−1 s−1.

Dark State of the Thiele Hydrocarbon: Efficient Solvatochromic Emission from a Nonpolar Centrosymmetric Singlet Diradicaloid

“…Singlet diradicaloids (SDs) are emerging as a promising class of molecular materials due to their potential multiple applications in several fields. , Many examples of SDs have been reported as conductive materials, , semiconductors in organic field-effect transistors (OFETs), − singlet-fission species for organic photovoltaics (OPV), − near-infrared (NIR)-absorbing chromophores, and dyes for nonlinear optics (NLO). , A widely underestimated property of these versatile compounds is their luminescence. ,− This is quite surprising since the first-ever synthesized SD, the Thiele hydrocarbon ( TH ) (Figure ), was described as fluorescent in solution and slightly oxygen- and light-sensitive . Probably, its photosensitivity and essentially quinoidal ground-state configuration limited the interest in the luminescence properties owned by the simplest para -quinodimethane ( p QDM) diradicaloid.…”

Recent progress in pyrazinacenes containing nonbenzenoid rings: synthesis, properties and applications

“…Furthermore, a long spin lattice relaxation time ( T 1 ) of 4.3 ms and quantum phase memory time ( T 3 ) of 3.0 ms were observed in m-DIP2 solution, indicating its promising applications in organic spintronics. Later on, the Bunz group 56 did a similar work and successfully synthesized a group of diindenopyrazines 43a–g through three different routes depending on the substitution groups (Scheme 7b). They found that the solubility, redox potentials, and optical properties could be modulated by the introduction of different functional aryl groups on the 6- and 12-positions.…”

Recent advances in versatile pyridazine-cored materials: principles, applications, and challenges

“…This has increased the demand for HAH-related structural design, simple and affordable synthesis techniques, and efficient device performance optimization. Hence, a significant variety of HAHs based on various p-conjugated core units, such as sixmembered diazines, [7][8][9][10][11][12][13] acridones, [14][15][16][17] quinoxalines, [18][19][20][21] pyrimidines, 22,23 triazines, 24 and five-membered imidazoles [25][26][27] and pyrroles, 28,29 have emerged in the past decades. Among these, p-conjugated pyridazine derivatives (PDs), [29][30][31][32][33][34][35] a type of HAH with PD-unit(s) in the conjugated skeleton, have drawn great attention because of their distinct properties, relating to the adjacent sp 2 -N pair, including excellent structural modifiability, unique supramolecular recognition and assembly capability, and potentially excellent optoelectronic properties in devices.…”