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[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
Reductive elimination of ArCF3 from bidentate Pd(II) complexes: a computational study.
Philipp Anstaett1, Franziska Schoenebeck
1Laboratory for Organic Chemistry, ETH Zürich, Wolfgang-Pauli-Strasse 10, 8093 Zürich, Switzerland.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|September 20, 2011
Summary
Computational studies reveal that Xantphos ligands enhance palladium-catalyzed ArCF(3) reductive elimination by reducing steric repulsion and increasing electronic interactions in the transition state. Ligand substituents, not bite angle, primarily dictate reactivity.
Area of Science:
- Organometallic Chemistry
- Computational Chemistry
- Catalysis
Background:
- Palladium-catalyzed cross-coupling reactions are vital in organic synthesis.
- Understanding ligand effects on reductive elimination is crucial for catalyst design.
- ArCF(3) compounds are important synthetic intermediates.
Purpose of the Study:
- Investigate the reductive elimination of ArCF(3) from Pd(II) complexes.
- Elucidate the role of phosphine ligand bite angle and substituents on reactivity.
- Determine factors governing catalytic efficiency.
Main Methods:
- Quantum mechanics/Quantum mechanics' (QM/QM') and QM/Molecular Mechanics (QM/MM) studies.
- CP2K molecular dynamics simulations.
- Ligand decomposition analysis to assess steric and electronic properties.
Main Results:
- Xantphos-derived complexes show higher reactivity due to reduced steric repulsion and enhanced electronic interactions in the transition state.
- DPPE complexes exhibit increased steric hindrance in the transition state, raising the reaction barrier.
- No direct correlation between bite angle and reactivity was observed, except for ligands with large substituents.
Conclusions:
- Ligand substituents significantly influence the steric and electronic landscape of the transition state.
- Reactivity is governed by a balance of steric and electronic factors, not solely bite angle.
- Catalyst design should consider substituent effects for optimizing ArCF(3) reductive elimination.
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