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Congratulations to Martin B. Johansen, Oliver R. Gedde, Thea S. Mayer and Troels Skrydstrup on their newly published article!

Access to Aryl and Heteroaryl Trifluoromethyl Ketones from Aryl Bromides and Fluorosulfates with Stoichiometric CO

Abstract
We report a sequential one-pot preparation of aromatic trifluoromethyl ketones starting from readily accessible aryl bromides and fluorosulfates, the latter easily prepared from the corresponding phenols. The methodology utilizes low pressure carbon monoxide generated ex situ from COgen to generate Weinreb amides as reactive intermediates that undergo monotrifluoromethylation affording the corresponding aromatic trifluoromethyl ketones (TFMKs) in good yields. The stoichiometric use of CO enables the possibility for accessing ¹³C-isotopically labeled TFMK by switching to the use of ¹³COgen.

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Congratulations to the Leif Hammarström research group at Uppsala University on their ercently accepted manuscript!

From non-innocent to guilty: on the role of redox-active ligand in the electro-assisted reduction of CO₂ mediated by a cobalt(II)-polypyridyl complex
N. Queyriaux, K. Abel, J. Fize, J. Pécaut, M. Orio and L. Hammarström
Sustainable Energy & Fuels (2020) accepted 11/5 2020

 Abstract

The electrochemical behavior of [Co(bapbpy)Cl]⁺ [1-Cl]⁺, a pentacoordinated polypyridyl cobalt(II) complex containing a redox-active pseudo-macrocyclic ligand (bapbpy: 6,6’-bis-(2-aminopyridyl)-2,2’-bipyridine) has been investigated in DMF. Cyclic voltammograms (CV), recorded in the presence of increasing amounts of chloride anions, highlighted the existence of an equilibrium with the neutral hexacoordinated complex. Under a CO₂ atmosphere, CVs of [Co(bapbpy)Cl]⁺ exhibit significant current enhancement assigned to CO₂ catalytic reduction. Controlled-potential electrolysis experiments confirmed formation of CO and HCOOH as the only identifiable products. The addition of water or chloride ions was shown to affect the distribution of the products obtained, as well as the faradaic efficiency associated with their electrocatalytic generation. A combination of electrochemical techniques, chemical reductions, spectroscopic measurements (UV-Vis and IR) and quantum chemical calculations suggests that the ability of the bapbpy ligand to be reduced at moderately negative potentials drastically limits the catalytic performances of [1-Cl]⁺, by stabilizing the formation of a catalytically-competent CO₂-adduct that only slowly reacts with oxide acceptors to evolve towards the desired reduction products.