The design of supramolecular organic radical cages and frameworks is one of the main challenges in supramolecular chemistry. Their interesting material properties and wide applications make them very promising for (photo)redox catalysis, sensors, or host-guest spin-spin interactions. However, the high reactivity of radical organic systems makes the design of such supramolecular radical assemblies challenging. Here, we report the on-surface synthesis of a purely organic supramolecular radical framework on Au(111), by combining supramolecular and on-surface chemistry. We employ a tripodal precursor, functionalized with 7-azaindole groups that, catalyzed by a single gold atom on the surface, forms a radical molecular product constituted by a π-extended fluoradene-based radical core. The radical products self-assemble through hydrogen bonding, leading to extended 2D domains ordered in a Kagome-honeycomb lattice. This approach demonstrates the potential of on-surface synthesis for developing 2D supramolecular radical organic chemistry.

CATRIN RCPTM Palacký University Šlechtitelu° 27 783 71 Olomouc Czech Republic

Département de Raffinage et Pétrochimie Faculté de Pétrole Gaz et Énergies Renouvelables Université de Kinshasa BP 127 Kinshasa XI République Démocratique du Congo

Department of Organic Chemistry University of Murcia Campus of Espinardo 30100 Murcia Spain

Department of Physical Chemistry Faculty of Science Palacký University 17 Listopadu 12 779 00 Olomouc Czech Republic

Faculty of Nuclear Sciences and Physical Engineering Czech Technical University Prague Břehová 78 7 11519 Prague 1 Czech Republic

Institute of Physics of Czech Academy of Sciences Cukrovarnická 10 16200 Prague 6 Czech Republic

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