Publications by authors named "Murielle Berlande"

The Cu-glutathione (GSH) redox system, essential in biology, is designed here as a supramacromolecular assembly in which the tetrahedral 18e Cu(I) center loses a thiol ligand upon adsorption onto ZIF-8, as shown by EXAFS and DFT calculation, to generate a very robust 16e planar trigonal single-atom Cu(I) catalyst. Synergy between Cu(I) and ZIF-8, revealed by catalytic experiments and DFT calculation, affords CO conversion into high-value-added chemicals with a wide scope of substrates by reaction with terminal alkynes or propargyl amines in excellent yields under mild conditions and reuse at least 10 times without significant decrease in catalytic efficiency.

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Hydrogen (H) generation and storage are actively investigated to provide a green source of energy, and formic acid (HCOOH), a major product obtained from the biomass, is regarded as a productive source of H. Therefore, improvements in heterogeneous catalysts are called for. Here, a novel type of catalyst support is proposed involving simple addition of the mixture of metal ion precursors to core-shell ZIF-8@ZIF-67, followed by reduction with NaBH, with performances surpassing those obtained using nanocatalysts in ZIF-8 or ZIF-67.

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The first example of an enantioselective carbocyclization of an alkyne-containing substrate catalyzed by chiral Brønsted acids was achieved. The use of the 2-hydroxynaphthyl substituent on the alkyne as a directing group constituted the key parameter enabling both efficient regioselective protonation of the carbon-carbon triple bond and chiral induction. The key cationic intermediate could be depicted either as a cationic vinylidene ortho-quinone methide or a stabilized vinyl cation.

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In order to explore the different mechanisms possibly occurring in the Au-catalysed cross-coupling of ArN2BF4 and ArB(OH)2 in the presence of CsF, various stoichiometric experiments were performed on gold complexes with (P,N) ligands. Employing 2-pyridylphenyl-diphenylphosphine allowed us to suggest three different mechanistic pathways, starting either with a transmetallation step, via two consecutive single electron transfers, or by implying a transmetallation between Au(i) and Au(iii) species. Moreover, when using commercially available chiral (P,N) ligands, the asymmetric formation of atropoisomeric biaryls from suitable aryldiazonium salts and arylboronic acids could be achieved with e.

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A new class of silicon-based fluoride acceptors with a C-linked heterocycle as the leaving group was synthesized in one step from commercial chemicals, and linked to biomolecules. The resulting conjugates were efficiently 19F-fluorinated in aqueous mixtures, and switching to 18F-labelling provided nucleoside- and peptide-based bioconjugates with excellent molar activities suitable for biological applications.

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