On‐Surface Bottom‐Up Synthesis of Azine Derivatives Displaying Strong Acceptor Behavior

• Published in: Angewandte Chemie International Edition 2018-07, Vol.57 (28), p.8582-8586
• Main Authors: Ruiz del Árbol, Nerea, Palacio, Irene, Otero‐Irurueta, Gonzalo, Martínez, José I., de Andrés, Pedro L., Stetsovych, Oleksander, Moro‐Lagares, María, Mutombo, Pingo, Svec, Martin, Jelínek, Pavel, Cossaro, Albano, Floreano, Luca, Ellis, Gary J., López, María F., Martín‐Gago, José A.
• Format: Article
• Language: English
• Subjects: ab initio calculations; Aminophenol; Carbonyls; charge transfer; Chemical speciation; Chemical synthesis; Communication; Communications; Conjugation; Copper; Electronic structure; Interfaces; Molecular chains; Optoelectronic devices; Organic chemistry; photoelectron spectroscopy; scanning probe microscopy; Surface chemistry; Surface properties
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201804110

On‐surface synthesis is an emerging approach to obtain, in a single step, precisely defined chemical species that cannot be obtained by other synthetic routes. The control of the electronic structure of organic/metal interfaces is crucial for defining the performance of many optoelectronic devices. A facile on‐surface chemistry route has now been used to synthesize the strong electron‐acceptor organic molecule quinoneazine directly on a Cu(110) surface, via thermally activated covalent coupling of para‐aminophenol precursors. The mechanism is described using a combination of in situ surface characterization techniques and theoretical methods. Owing to a strong surface‐molecule interaction, the quinoneazine molecule accommodates 1.2 electrons at its carbonyl ends, inducing an intramolecular charge redistribution and leading to partial conjugation of the rings, conferring azo‐character at the nitrogen sites. A facile on‐surface route was used to synthesize the strong electron‐acceptor organic molecule quinoneazine directly on a Cu(110) surface, via thermally activated covalent coupling of para‐aminophenol precursors. The mechanism is described using in situ surface characterization and theoretical methods. Owing to a strong surface‐molecule interaction, the quinoneazine molecule accommodates 1.2 electrons at its carbonyl ends.