Highly Structure‐Selective On‐Surface Synthesis of Isokekulene Versus Kekulene
Abstract
Abstract The role of different facets of metal nanoparticles in steering reaction pathways is crucial for the design of heterogeneous catalysts with superior selectivity. As a prominent class of reactions, transition‐metal‐catalyzed carbon‐hydrogen (C─H) bond activation is widely used for the synthesis of base chemicals, modern organic materials, and pharmaceuticals. Here, we report orthogonal selectivity in intramolecular cyclodehydrogenation of a nonplanar cyclic precursor steered by different facets of a copper single crystal. On the Cu(110) surface, the previously unknown cycloarene isokekulene forms with a high selectivity of 92%, whereas reaction on the Cu(111) surface exclusively yields kekulene (>99%). Combining scanning tunneling microscopy with CO‐functionalized tips and density functional theory, we identify two adsorption geometries of the precursor, which react to the respective products. Isokekulene adopts two nonplanar adsorption configurations and exhibits strong molecule‐substrate interactions, explaining its preferential formation on Cu(110). This combined in‐solution and on‐surface synthesis approach represents an alternative route for the highly selective synthesis of molecules that are challenging to synthesize and process via conventional methods.
Article Details
Authors (18)
Zilin Ruan
Philipps-Universität Marburg, Fachbereich Chemie, Hans-Meerwein-Str. 4, 35032 Marburg, Germany
Qitang Fan
Hefei National Research Center for Physical Sciences at the Microscale, CAS Center for Excellence in Quantum Information and Quantum Physics, and New Cornerstone Science Laboratory
Alexander Reichmann
Institute of Physics, University of Graz, NAWI Graz Graz 8010 Austria
Faming Kang
Tim Naumann
Philipps-Universität Marburg, Fachbereich Chemie, Hans-Meerwein-Str. 4, 35032 Marburg, Germany
Simon Werner
Department of Chemistry Marburg University 35037 Marburg Germany
Olaf Kleykamp
Department of Chemistry Marburg University 35037 Marburg Germany
Jose Martinez‐Castro
Peter Grünberg Institute (PGI‐3), Forschungszentrum Jülich 52425 Jülich Germany
Felix Lüpke
Peter Grünberg Institute (PGI‐3), Forschungszentrum Jülich 52425 Jülich Germany
Anja Haags
Peter Grünberg Institute (PGI‐3), Forschungszentrum Jülich 52425 Jülich Germany
François C. Bocquet
Peter Grünberg Institute (PGI‐3), Forschungszentrum Jülich 52425 Jülich Germany
Christian Kumpf
Serguei Soubatch
Jörg Sundermeyer
Philipps-Universität Marburg, Fachbereich Chemie, Hans-Meerwein-Str. 4, 35032 Marburg, Germany
Peter Puschnig
Institute of Physics, NAWI Graz University of Graz Graz Austria
F. Stefan Tautz
J. Michael Gottfried
Philipps-Universität Marburg, Fachbereich Chemie, Hans-Meerwein-Str. 4, 35032 Marburg, Germany
Sabine Wenzel
Department of Chemistry Marburg University 35037 Marburg Germany