7 research outputs found
Bases de données périnatales et assurance de qualité. Validation des données, qualité des soins, contrôle des coûts
No full textCarbosilane Dendrons Containing a P-Stereogenic Phosphine at the Focal Point. Catalytic Behavior of Their Allylpalladium Complexes in the Asymmetric Hydrovinylation of Styrene
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Long-Lived Hole Stabilized at a Triphenylamine Core and Shielded by Rigid Phenylazomethine Dendrons: A Pulse Radiolysis Study
No full textDendrimers with a Copper(I) Bis(phenanthroline) Core: Synthesis, Electronic Properties, and Kinetics
No full textRole of Adamantane Amide Based on L-Proline Double-H Potential Organocatalyst in Aldol Reaction with Product Separated via Host-guest Interaction
No full textPhosphorus Functionalized Dendrimers and Hyperbranched Polymers: Is There a Need for Perfect Dendrimers in Catalysis?
No full textIn this paper we describe the facile and straightforward covalent functionalization of commercially available dendritic poly(propylenimine) and hyperbranched poly(ethylenimine) with P-containing functional groups. The P-functionalized macromolecules have been applied as multivalent ligands in the Pd-catalyzed allylic substitution reactions (batch and continuous process) using either morpholine or thiophenol as nucleophile. Palladium complexes of all described molecules are active in allylic substitution reactions. The PEI functionalized polymers appear more sensitive to small changes in the P/Pd ratio than the PPI analogues, but form catalysts that are more active. When used in a continuous flow process the macromolecules are completely retained by the nanofiltration membrane, while the catalytic activity decreases with time because of palladium depletion. This is more severe for the allylic thiolation, probably because of the stronger affinity of sulfur for palladium, facilitating palladium leaching
