Resumen: On-surface synthesis is emerging as a highly rational bottom-up methodology for the synthesis of molecular structures that are unattainable or complex to obtain by wet chemistry. Here, oligomers of meta-polyaniline, a known ferromagnetic polymer, were synthesized from para-aminophenol building-blocks via an unexpected and highly specific on-surface formal 1, 4 Michael-type addition at the meta position, driven by the reduction of the aminophenol molecule. We rationalize this dehydrogenation and coupling reaction mechanism with a combination of in situ scanning tunneling and non-contact atomic force microscopies, high-resolution synchrotron-based X-ray photoemission spectroscopy and first-principles calculations. This study demonstrates the capability of surfaces to selectively modify local molecular conditions to redirect well-established synthetic routes, such as Michael coupling, towards the rational synthesis of new covalent nanostructures. Idioma: Inglés DOI: 10.1002/anie.202009863 Año: 2020 Publicado en: ANGEWANDTE CHEMIE-INTERNATIONAL EDITION 59, 11 (2020), 23220-23227 ISSN: 1433-7851 Factor impacto JCR: 15.336 (2020) Categ. JCR: CHEMISTRY, MULTIDISCIPLINARY rank: 16 / 178 = 0.09 (2020) - Q1 - T1 Factor impacto SCIMAGO: 5.831 - Chemistry (miscellaneous) (Q1) - Catalysis (Q1)