Triplet Metallovinylidenes of Palladium and Platinum Based on a Chelating P/Diazoalkene Ligand
Abstract
Abstract Triplet carbenes featuring a metal adjacent to the carbene center (metallocarbenes; R─C─M) are an emerging class of diradicals within the field of reactive intermediates. Here, we report the synthesis of the first spectroscopically characterized triplet metallovinylidenes (R─C→M; M = Pt, Pd). The synthetic access is based on a rigid P/C chelating diazoalkene ligand and its coordination to Pt and Pd. The C/P chelating ligand geometrically constrains the R─C→M angle and inhibits free bending. Irradiation of the free diazoalkene ligand generates a triplet vinylidene, characterized by Q‐band electron paramagnetic resonance (EPR) spectroscopy. Irradiation of the metal coordination complexes (Pt and Pd) affords triplet metallovinylidenes, which were characterized at low temperatures including photochemically triggered in crystallo X‐ray diffraction. Combined FD‐FT THz‐EPR spectroscopy and SQUID measurements allowed the determination of the large triplet zero‐field splitting (ZFS) with D values of 124.5 cm −1 (Pt) and 8.0 cm −1 (Pd) in excellent agreement with the electronic structure obtained by high‐level quantum chemical calculations.
Article Details
Authors (12)
Max Amann
Fakultät für Chemie und Chemische Biologie Technische Universität Dortmund Otto‐Hahn‐Str.6 44227 Dortmund Germany
Maria Drosou
Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, Mülheim an der Ruhr 45470, Germany
Tarek Al Said
Helmholtz Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner-Platz 1, Berlin 14109, Germany
Alexander Allgaier
Institut für Physikalische Chemie Universität Stuttgart Stuttgart Germany
Yury Kutin
Department of Chemistry and Chemical Biology, Technical University Dortmund, Faculty for Chemistry and Chemical Biology
Patrick W. Antoni
Fakultät für Chemie und Chemische Biologie Technische Universität Dortmund Dortmund Germany
Julian J. Holstein
Department of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn Str. 6, Dortmund 44227, Germany
Müge Kasanmascheff
Department of Chemistry and Chemical Biology, Technical University Dortmund, Faculty for Chemistry and Chemical Biology
Joris van Slageren
Institute of Physical Chemistry and Center for Integrated Quantum Science and Technology, University of Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
Alexander Schnegg
Max Planck Institute for Chemical Energy Conversion, 34-36 Stiftstraße, Mülheim an der Ruhr 45470, Germany
Dimitrios A. Pantazis
Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, Mülheim an der Ruhr 45470, Germany
Max M. Hansmann
Fakultät für Chemie und Chemische Biologie Technische Universität Dortmund Dortmund Germany