Chemical and Redox Noninnocence of Pentane-2,4-dione Bis(S-methylisothiosemicarbazone) in Cobalt Complexes and Their Application in Wacker-Type Oxidation

Author(s)

Vincent Porte, Miljan N.M. Milunovic, Ulrich Knof, Thomas Leischner, Tobias Danzl, Daniel Kaiser, Tim Gruene, Michal Zalibera, Ingrid Jelemenska, Lukas Bucinsky, Sergio A.V. Jannuzzi, Serena DeBeer, Ghenadie Novitchi, Nuno Maulide, Vladimir B. Arion

Abstract

Cobalt complexes with multiproton- and multielectron-responsive ligands are of interest for challenging catalytic transformations. The chemical and redox noninnocence of pentane-2,4-dione bis(S-methylisothiosemicarbazone) (PBIT) in a series of cobalt complexes has been studied by a range of methods, including spectroscopy [UV-vis, NMR, electron paramagnetic resonance (EPR), X-ray absorption spectroscopy (XAS)], cyclic voltammetry, X-ray diffraction, and density functional theory (DFT) calculations. Two complexes [Co^III(H₂L^SMe)I]I and [Co^III(L^SMe)I₂] were found to act as precatalysts in a Wacker-type oxidation of olefins using phenylsilane, the role of which was elucidated through isotopic labeling. Insights into the mechanism of the catalytic transformation as well as the substrate scope of this selective reaction are described, and the essential role of phenylsilane and the noninnocence of PBIT are disclosed. Among the several relevant species characterized was an unprecedented Co(III) complex with a dianionic diradical PBIT ligand ([Co^III(L^SMe••)I]).

Organisation(s)

Department of Organic Chemistry, Department of Inorganic Chemistry, Core Facility Crystal Structure Analysis, Research Platform Next Generation Macrocycles to Address Challenging Protein Interfaces

External organisation(s)

Novartis Pharma AG, Slovak University of Technology in Bratislava, Max-Planck-Institut für Chemische Energiekonversion, Centre National de la Recherche Scientifique (CNRS), Grenoble

Journal

JACS Au

Volume

4

Pages

1166-1183

No. of pages

18

ISSN

2691-3704

DOI

https://doi.org/10.1021/jacsau.4c00005

Publication date

03-2024

Peer reviewed

Yes

Austrian Fields of Science 2012

104015 Organic chemistry, 104017 Physical chemistry

Keywords

ASJC Scopus subject areas

Analytical Chemistry, Chemistry (miscellaneous), Physical and Theoretical Chemistry, Organic Chemistry

Portal url

https://ucrisportal.univie.ac.at/en/publications/03180687-0ae9-4a6e-857e-c82226b4ed79