title: Palladium-Catalysed Cross-Coupling Reactions Controlled by Noncovalent Zn⋅⋅⋅N Interactions.
abstract: Non-covalent interactions between halopyridine substrates and catalytically inert building blocks, namely zinc(II)-porphyrins and zinc(II)-salphens, influence the catalytic outcome of Suzuki-Miyaura and Mizoroki-Heck palladium-catalysed cross-coupling reactions. The weak Zn⋅⋅⋅N interactions between halopyridine substrates and zinc(II)-containing porphyrins and salphens, respectively, were studied by a combination of1H NMR spectroscopy, UV/Vis studies, Job-Plot analysis and, in some cases, X-ray diffraction studies. Additionally, the former studies revealed unique supramolecular polymeric and dimeric rearrangements in the solid state featuring weak Br⋅⋅⋅N (halogen bonding), C-H⋅⋅⋅π, Br⋅⋅⋅π and π⋅⋅⋅π interactions. The reactivity of halopyridine substrates in homogeneous palladium-catalysed cross-coupling reactions was found to correlate with the binding strength between the zinc(II)-containing scaffolds and the corresponding halopyridine. Such observation is explained by the unfavourable formation of inactive over-coordinated halopyridine⋅⋅⋅palladium species. The presented approach is particularly appealing for those cases in which substrates and/or products deactivate (or partially poison) a transition-metal catalyst.
authors.affiliation: Organometallics: Materials and Catalysis Laboratory, Institut des Sciences Chimiques de Rennes-UMR 6226, CNRS-Université de Rennes 1, 35042, Rennes Cedex, France.|Département de Chimie, Université Kasdi Merbah d'Ouargla, 30000, Ouargla, Algeria.|Ecole Nationale Polytechnique d'Oran, Laboratoire de Chimie Fine, Université d'Oran-1 Ahmed Ben Bella, 31100, Oran, Algeria.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Kadri
authors.affiliation: Organometallics: Materials and Catalysis Laboratory, Institut des Sciences Chimiques de Rennes-UMR 6226, CNRS-Université de Rennes 1, 35042, Rennes Cedex, France.
authors.forename: Jingran
authors.initials: J
authors.lastname: Hou
authors.affiliation: X-ray Diffraction Centre, Institut des Sciences Chimiques de Rennes-UMR 6226, CNRS-Université de Rennes 1, 35042, Rennes Cedex, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Dorcet
authors.affiliation: X-ray Diffraction Centre, Institut des Sciences Chimiques de Rennes-UMR 6226, CNRS-Université de Rennes 1, 35042, Rennes Cedex, France.
authors.forename: Thierry
authors.initials: T
authors.lastname: Roisnel
authors.affiliation: Département de Chimie, Université Kasdi Merbah d'Ouargla, 30000, Ouargla, Algeria.
authors.forename: Lazhar
authors.initials: L
authors.lastname: Bechki
authors.affiliation: Ecole Nationale Polytechnique d'Oran, Laboratoire de Chimie Fine, Université d'Oran-1 Ahmed Ben Bella, 31100, Oran, Algeria.
authors.forename: Abdellah
authors.initials: A
authors.lastname: Miloudi
authors.affiliation: Organometallics: Materials and Catalysis Laboratory, Institut des Sciences Chimiques de Rennes-UMR 6226, CNRS-Université de Rennes 1, 35042, Rennes Cedex, France.
authors.forename: Christian
authors.identifier: http://orcid.org/0000-0002-2220-1458
authors.initials: C
authors.lastname: Bruneau
authors.affiliation: Organometallics: Materials and Catalysis Laboratory, Institut des Sciences Chimiques de Rennes-UMR 6226, CNRS-Université de Rennes 1, 35042, Rennes Cedex, France.
authors.forename: Rafael
authors.identifier: http://orcid.org/0000-0002-0961-4530
authors.initials: R
authors.lastname: Gramage-Doria
keywords: noncovalent interactions; palladium; porphyrin; pyridine; salphen