Synthesis of polyfunctional ligands for the coordination chemistry and catalysis

Le but de ce travail de thèse été de développer de nouvelles familles de ligands polyfonctionnels pour étudier, dans un premier temps, leur chimie de coordination vis-à-vis de centres métalliques et dans un second temps, en fonction des espèces formées, lThe objective of this thesis was the developement of new polyfunctional ligands families to study, in a first time, their coordination chemistry towards metallic centers, and in a second time, in view of the nature of the species formed their physical an

Synthèse de ligands polyfonctionnels pour la chimie de coordination et la catalyse

Le but de ce travail de thèse été de développer de nouvelles familles de ligands polyfonctionnels pour étudier, dans un premier temps, leur chimie de coordination vis-à-vis de centres métalliques et dans un second temps, en fonction des espèces formées, leurs propriétés physiques et/ou catalytiques. Les combinaisons potentiellement les plus intéressantes étaient basées sur l association de sites donneurs connus pour former des liaisons fortes avec les métaux envisagés, comme les phosphines (P-) ou les carbènes N-hétérocycliques (CNHC-), avec des sites donneurs plus labiles, comme une fonction thioéther (S-). Ce type d association permet l élaboration de systèmes dits hémilabiles , qui se sont montrés d excellents candidats pour des applications en catalyse homogène. Des ligands de type : diaminophosphine/thioéther : P-, P-, S- ont ainsi été développés. Ces ligands ont montré une grande richesse de modes de coordination, dont il a résulté une grande diversité de complexes organométalliques. Les seconds ligands ciblés étaient de type carbènes N-hétérocycliques (NHC), portant soit un groupement thioéther sur un des atomes d azote du cycle : S,CNHC ou sur chaque azote : S,CNHC,S. Leurs précurseurs ont pu être synthétisés dans des conditions ecofriend , novatrices et permettant une grande variabilité. Ces ligands offrent une grande variété de modes de coordination qui s est traduit dans leurs complexes de coordination d argent(I) et de palladium(II). Le potentiel catalytique de ces composés a été évalué en réaction de couplage croisé de Suzuki-Miyaura, et a révélé une très bonne activité vis-à-vis des substrats bromés.The objective of this thesis was the developement of new polyfunctional ligands families to study, in a first time, their coordination chemistry towards metallic centers, and in a second time, in view of the nature of the species formed their physical and/or catalytic properties. The combination of donor sites which seems the most interesting was based on the association of donors known to form strong interactions with the metals envisaged, like phosphines (P-) or N-heterocyclic carbenes (CNHC-), with more labile donors, like a thioether function (S-). This association allows the formation of systems called hemilabiles , which showed good candidates for homogenous catalytic applications. Ligands of type: diaminophosphine/thioether: P-, P-, S- have been developed. These ligands showed various coordination modes, from which a large variety of organometallic complexes were obtained. The second target ligands were of type: N-heterocyclique carbenes (NHC), bearing a thioether group on one nitrogen atom from the cycle: S,CNHC or on both nitrogen: S,CNHC,S. Their precursors have been prepared in ecofriend conditions and allowing a large variability. The ligands offer also various coordination modes illustrated by their silver(I) and palladium(II) complexes. The catalytic potential of these compounds has been evaluated in the Suzuki- Miyaura cross-coupling reaction and revealed a very good activity towards brominated substrates.STRASBOURG-Sc. et Techniques (674822102) / SudocSudocFranceF

Homolytically weak metal-carbon bonds make robust controlled radical polymerizations systems for “less-activated monomers”

International audienceThis article is an account of work, mostly carried out in the authors' laboratory, on the use of organometallic compounds with homolytically fragile metal-carbon bonds as dormant species in the controlled radical polymerization of a variety of monomers in what is now universally called "organometallic-mediated radical polymerization" (OMRP). The article retraces a brief history of OMRP, shows how it can potentially intervene in every radical polymerization process based on atom transfer (ATRP), which is a more popular controlling method where the metal plays a catalytic role, and how it can be in competition with another catalyzed process involving chain transfer to monomer (CCT). It highlights the challenges of controlled radical polymerization in the area of the "less activated monomers" (LAMs) and particularly the problem of the monomer addition errors, demonstrating how ligand engineering and coordination chemistry constitute additional handles, not available to other moderating species, providing acceptable ad hoc solutions. It details how OMRP could achieve unsurpassed levels of control for two specific monomers: vinyl acetate (VAc) and vinylidene fluoride (VDF). Finally, it lays the principles for the development of efficient chain transfer catalysts for less activated monomers

Recent advances in S-functionalized N-heterocyclic carbene ligands: From the synthesis of azolium salts and metal complexes to applications

International audienc

Thioether-Functionalized N-Heterocyclic Carbenes: Mono- and Bis-(S,CNHC) Palladium Complexes, Catalytic C−C Coupling, and Characterization of a Unique Ag4I4 (S,CNHC)2 Planar Cluster

International audienc

Coordination chemistry of neutral mono-oxide, sulfide and selenide bis(diphenylphosphino)amine (DPPA)-based ligands and their N-substituted/functionalized derivatives

International audienceThis review provides a summary, including spectroscopic and structural data, of the metal complexes accessible with mono-oxide, sulfide and selenide bis(diphenylphosphino)amine (DPPA)-based ligands and their N-substituted/functionalized derivs. The nature of the E (O, S, Se) donor in these mixed P,P=E donor ligands strongly influences the nature of the resulting metal complexes, which can incorporate the DPPA-type ligand(s) as P-monodentate or P,E-chelate. When available, a comparison between the reactivity of the mixed P,P=E and parent P,P systems is given. The catalytic applications of P,E-supported metal complexes are also discussed

Versatile coordination modes of novel hemilabile S-NHC ligands

International audienc

Mono-, di- and tetranuclear complexes and clusters with bromine-functionalized bis(diphenylphosphino)-amine ligands

International audienc

Metal Complexes as Catalysts/Moderators for Polymerization Reactions

International audienceThis article highlights the most representative results on the use of coordination compounds in polymerization reactions, since the version of the Comprehensive Coordination Chemistry II by Gibson and Marshall (2003). Noteworthy developments of more efficient catalysts and related significant advancements in coordination polymerization of olefins, radical polymerization, lactide and related cyclic esters polymerization and CO2/epoxides polymerization are discussed therei