The charge transport properties of dicyanomethylene-functionalised violanthrone derivatives

• Sondos A. J. Almahmoud,
• Joseph Cameron,
• Dylan Wilkinson,
• Michele Cariello,
• Claire Wilson,
• Alan A. Wiles,
• Peter J. Skabara and
• Graeme Cooke

Beilstein J. Org. Chem. 2024, 20, 2921–2930, doi:10.3762/bjoc.20.244

• dicyanomethylene-functionalised violanthrone derivatives (3a, 3b and 3c) featuring different alkyl substituents. It is found that the introduction of the electron-deficient dicyanomethylene groups significantly improves the optical absorption compared to their previously reported precursors 2a–c. All compounds are

• field-effect transistor; organic semiconductor; violanthrone; Introduction Recently, organic semiconductors have received considerable attention due to their potential technological applications in semiconductor devices, such as organic field-effect transistors (OFETs) [1][2], organic light-emitting

• structural features of violanthrones suggest that these materials may possess similar charge transport, optical and electrochemical properties to those of PDIs. However, the larger π-conjugated system of violanthrone, along with the two carbonyl groups, increases the possibility of stronger π–π

Metal and metal-free photocatalysts: mechanistic approach and application as photoinitiators of photopolymerization

• Jacques Lalevée,
• Sofia Telitel,
• Pu Xiao,
• Marc Lepeltier,
• Frédéric Dumur,
• Fabrice Morlet-Savary,
• Didier Gigmes and
• Jean-Pierre Fouassier

Beilstein J. Org. Chem. 2014, 10, 863–876, doi:10.3762/bjoc.10.83

• (R3SiH) and exhibits a relatively similar performance in photoinitiating systems of cationic polymerization [45][46][47][48][49][50][51][52][54][55]. Examples of metal-free pure organic PICs for FRP and FRPCP have also been very recently reported [54][55][61][62]. For example, they involve a violanthrone

• dye Vi [61][62] or an anthracene derivative (e.g. bis[(triisopropylsilyl)ethynyl]anthracene) [54][55] as PIC, Ph2I+ as eA and TTMSS as Add (see the simplified Scheme 9 based on Scheme 6). Using violanthrone-79/Ph2I+/TTMSS allowed, for the first time, the formation of an initiating cationic species

• +) as PIC which is reduced here into Ru(bpy)3+ although as shown above, it usually works through an oxidation cycle [61][62]. A violanthrone derivative (violanthrone-79) is employed as eD and Ph2I+ as B-Y+ (see Scheme 5); TTMSS is added. This multicomponent system works according to the detailed Scheme