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The integration of catalytically active centers into a solid support without loss of performance compared to their homogeneous analogs is still a major challenge. In this context, a molecularly defined support as macroligand, i.e. a solid acting like the ligand in the corresponding molecular complex, can be considered as a key to bridge the gap between molecular and heterogeneous catalysis. Porous solids such as Metal-Organic Frameworks (MOF) and purely organic Porous Organic Polymers (POP) are appealing candidates. Using a series of heterogeneous catalysts based on MOF and POP as macroligands of organometallic complexes, we show that both homogeneous and heterogenized catalysts follow the same linear correlation between the electronic effect of the ligand, described by the Hammett parameter, and the catalytic activity. The rational design of novel heterogeneous catalysts can thus be guided by rules from molecular chemistry., L'intégration de centres catalytiquement actifs sur un support solide sans perte de performance par rapport à la version en solution reste un défi majeur. Dans ce contexte, un support défini au niveau moléculaire en tant que macroligand, c'est-à-dire un solide agissant comme le ligand dans le complexe moléculaire correspondant, permet de créer un lien entre la catalyse homogène et hétérogène. Les solides poreux tels que les Metal-Organic Frameworks (MOF) et Polymères Organiques Poreux (POP) sont des candidats prometteurs. En utilisant une série de catalyseurs hétérogènes à base de MOF et de POP en tant que macroligands pour des complexes organométalliques hétérogénéisés, nous montrons que les catalyseurs homogènes et hétérogènes suivent la même corrélation linéaire entre l'effet électronique du ligand, décrit par la constante de Hammett, et l'activité catalytique. La conception rationnelle de nouveaux catalyseurs hétérogènes peut donc être guidée par des règles de la chimie moléculaire.

C123 is a €6.4 million European Horizon 2020 (H2020) integrated project running from 2019 to 2023, bringing together 11 partners from seven different European countries. There are large reserves of stranded natural gas waiting for a viable solution and smaller scale biogas opportunities offering methane feedstocks rich in carbon dioxide, for which utilisation can become an innovation advantage. C123 will evaluate how to best valorise these unexploited methane resources by an efficient and selective transformation into easy-to-transport liquids such as propanol and propanal that can be transformed further into propylene and fed into the US$6 billion polypropylene market. In C123 the selective transformation of methane to C3 hydrocarbons will be realised via a combination of oxidative conversion of methane (OCoM) and hydroformylation, including thorough smart process design and integration under industrially relevant conditions. All C123 technologies exist at TRL3 (TRL = technology readiness level), and the objectives of C123 will result in the further development of this technology to TRL5 with a great focus on the efficient overall integration of not only the reaction steps but also the required purification and separation steps, incorporating the relevant state-of-the-art engineering expertise.

International audience; The integration of catalytically active centers into a solid support without loss of performance compared to their homogeneous analogs is still a major challenge. In this context, a molecularly defined support as macroligand, i.e. a solid acting like the ligand in the corresponding molecular complex, can be considered as a key to bridge the gap between molecular and heterogeneous catalysis. Porous solids such as Metal-Organic Frameworks (MOF) and purely organic Porous Organic Polymers (POP) are appealing candidates. Using a series of heterogeneous catalysts based on MOF and POP as macroligands of organometallic complexes, we show that both homogeneous and heterogenized catalysts follow the same linear correlation between the electronic effect of the ligand, described by the Hammett parameter, and the catalytic activity. The rational design of novel heterogeneous catalysts can thus be guided by rules from molecular chemistry.; L'intégration de centres catalytiquement actifs sur un support solide sans perte de performance par rapport à la version en solution reste un défi majeur. Dans ce contexte, un support défini au niveau moléculaire en tant que macroligand, c'est-à-dire un solide agissant comme le ligand dans le complexe moléculaire correspondant, permet de créer un lien entre la catalyse homogène et hétérogène. Les solides poreux tels que les Metal-Organic Frameworks (MOF) et Polymères Organiques Poreux (POP) sont des candidats prometteurs. En utilisant une série de catalyseurs hétérogènes à base de MOF et de POP en tant que macroligands pour des complexes organométalliques hétérogénéisés, nous montrons que les catalyseurs homogènes et hétérogènes suivent la même corrélation linéaire entre l'effet électronique du ligand, décrit par la constante de Hammett, et l'activité catalytique. La conception rationnelle de nouveaux catalyseurs hétérogènes peut donc être guidée par des règles de la chimie moléculaire.

International audience; A protocol for ab initio structure determination of powdered solids at natural isotopic abundance by combining solid-state NMR spectroscopy, crystal structure prediction and DFT chemical shift calculations is used to determine the crystal structures of a series of drug molecules: flutamide, flufenamic acid, cocaine and theophylline. For flutamide and flufenamic acid we find that assigned 1H isotropic chemical shifts provide sufficient discrimination so as to determine the correct structures from a set of predicted structures using the root-mean-square deviation between experimentally determined and calculated chemical shifts. In both cases neither unassigned 1H shifts nor 13C shifts could be used to determine the structures. The correct structures were determined to within an atomic rmsd of less than0.12 Å with respect to the known structures. For theophylline the NMR spectrum is too simple to allow unambiguous structure selection. We show how the information contained in the NMR chemical shifts is complementary (orthogonal) to PXR D. Combining 1 H NMR chemical shift, CSP/DFT and PXRD leads to a very robust structure determination protocol, with no hypothesis, and no bias. We also use this procedure to determine for the first time the crystal structure of a pharmaceutically pertinent molecule with previously unknown structure, where previous attempts by X-ray diffraction alone had not been successful. Combining 1H solid-state NMR spectroscopy with first-principles calculations can also be applied to the crystal structure determination of metal organic frameworks. We demonstrate this by reporting the discovery of the previously unknown crystal structure of a novel porous imidazolate substituted metal organic framework with possible applications as a H2 storage material. 1H NMR experiments provided a description of the proton environments within the MOF, which in combination with DFT chemical shift calculations and PXRD led to the elucidation of the complete crystal structure.

The enantiomerically pure iridium title complex, [Ir(C/sub>13H19N2O2S)(C10H15)Cl]•CHCl3, has the Ir atom in the S configuration, with a distorted octahedral geometry.