Gallou, Fabrice (2022) Selectivity Arising from Synergy Between Two Metals and Aqueous Micelle: Nickel-Palladium Bimetallic Nanoparticles for Facile and Highly Selective 1,4-Reduction of Chalcones. ACS Appl. Mater. Interfaces, 14 (5). pp. 6754-6761.

Abstract

By harnessing the synergy between Ni(0), Pd(0), and an aqueous micelle of proline-derived PS-750-M amphiphile, phosphine ligand-free ultrasmall nanoparticles (NPs) of Ni(0)-Pd(0) are developed for highly selective 1,4-reductions of enones. In the NP, Ni(0)-bound Pd(0) atoms are found to only react with the most electron-deficient double bond due to the electron enriching character of Pd and fine-tuning of the bimetallic NP’s d-band. Most notably, NPs containing a minimal amount of Pd (Ni:Pd = 25:1) were highly selective for 1,4-reductions of enones without affecting different types of N-and O-benzyl, aldehyde, nitrile, and nitro functional groups. The catalytic selectivity is investigated on a broad range of substrates, including a gram-scale reaction. Control experiments reveal Ni, Pd, and a micelle of PS-750-M are required for higher selectivity. Evidence of the metal-micelle binding was supported by a surface-enhanced Raman spectroscopy (SERS) study of the NPs and their components. Optical imaging, high-resolution transmission electron microscopy (HRTEM), and energy-dispersive X-ray spectroscopy (EDX) analyses were performed to reveal the formation of NP-containing micelles or vesicles, NP morphology, particle size distribution, and chemical composition, while X-ray photoelectron spectroscopy (XPS) measurements unveiled the oxidation state of each metal in the bimetallic NPs.

Item Type:	Article
Date Deposited:	08 Mar 2022 00:45
Last Modified:	08 Mar 2022 00:45
URI:	https://oak.novartis.com/id/eprint/45916