Analyzing mechanisms in Co(i) redox catalysis using a pattern recognition platform

Abstract

Redox catalysis has been broadly utilized in electrochemical synthesis due to its kinetic advantages over direct electrolysis. The appropriate choice of redox mediator can avoid electrode passivation and overpotential, which...

Comparing Halogen Atom Abstraction Kinetics for Mn(I), Fe(I), Co(I), and Ni(I) Complexes by Combining Electroanalytical and Statistical Modeling

“…This complexity also can be manifested in measuring essential kinetic data for these processes, which is often a requirement to gain insight into the controlling events that can influence catalysis [9,10] . In this context, we have recently reported the use of a series of electroanalytical methods to analyze several ligated Co(I) complexes in the activation of a wide range of benzylic halides [11–13] . These tools provided access to rapid kinetic data collection allowing for the application of traditional physical organic experiments (e. g., kinetic isotope effects, Hammett studies), combined with statistical modelling of catalyst/substrate descriptors to provide insight into the mechanism of substrate activation.…”

“…Specifically, analysis of a pyridine−oxazoline (Pyrox) bidentate ligand set, [11] resulted in the proposal of a halogen atom abstraction mechanism for the resulting Co(I) complexes. In contrast, investigation of a Co(I) complex bearing two 2,6‐bis(pyrazol‐1‐yl)pyridine (BPP) tridentate ligands [12] provided evidence of an alternative mechanism of an outer‐sphere electron transfer pathway of benzylic halides. A more recent study by Liu and Diao et al disclosed a halogen‐atom dissociation mechanism for the activation of alkyl halides by a catalysis‐relavent square planar Ni(I)(BPy) complex [9c] .…”

Homogeneous molecular catalysis of the electrochemical reduction of N2O to N2: redox vs. chemical catalysis

“…3 Being able to distinguish if a given catalyst is acting as a redox mediator or a chemical catalyst is therefore of prime importance in the endeavour to design efficient molecular catalysts for given small molecule activation. 4 It is in particular crucial to understand how the catalytic effect is related to the nature of the catalyst, a subject of debate in O 2 or CO 2 reduction for example. [5][6][7][8] We have recently emphasized the potential of the nitrous oxide (N 2 O) electrochemical reduction reaction leading to inert dinitrogen (N 2 ) 9 since N 2 O is a greenhouse gas presenting a long lifetime, a higher global warming potential than CO 2 and CH 4 and playing a major role in the cycles of ozone destruction.…”

Computational Organometallic Catalysis: Where We Are, Where We Are Going

“…[62] Electroanalytical techniques have been combined with parameterization tools, which include DFT calculations, to uncover reaction mechanism in redox catalysis. [63]…”

“…The total data set used consisted of 1510 catalytic cycles derived from DFT computations and 491 catalytic cycles derived from machine learned profiles [62] . Electroanalytical techniques have been combined with parameterization tools, which include DFT calculations, to uncover reaction mechanism in redox catalysis [63] …”