Palladium Nanoparticles in Polyols: Synthesis, Catalytic Couplings, and Hydrogenations

Abstract

Alcohols, in particular polyols, are well-known for the synthesis of metal nanoparticles often acting as reducing agents, solvents, and stabilizers. Given not only their structural flexibility depending on the number of OH functions and their inherent H bonding interactions, but also the wide range of polyol molecular weights readily available, different physico-chemical properties (boiling point, polarity, viscosity) could be exploited towards the synthesis of well-defined nanomaterials. In particular, the relevance of the supramolecular structure of polyols has a fundamental impact on the formation of metal nanoparticles thereby favoring the dispersion of the nanoclusters. In the field of the metal-based nanocatalysis, palladium occupies a privileged position mainly due to its remarkable versatility in terms of reactivity representing a foremost tool in synthesis. In this review, we describe the controlled synthesis of Pd-based nanoparticles in polyol medium focusing on the progress in terms of tailoring size, morphology, structure, and surface state. Moreover, we discuss the use of 4.2. C(sp)-C(sp 2) Sonogashira cross-coupling 4.3. C(sp 2)-C(sp 2) Hiyama-Denmark cross-coupling 4.4. C(sp 2)-C(sp 2) Heck-Mizoroki cross-coupling 4.5. C(sp 2)-C(sp 2 /sp 3) Suzuki-Miyaura cross-coupling 4.5.1. In PEG and glycerol media 4.5.2. Solid-supported nanocatalysts 4.6. C(sp 2)-C(sp 2)-C(sp 2) Carbonylative Suzuki cross-coupling 4.7. C(sp 2)-C(sp 2) Ullmann-type homo-coupling 4.8. Miscellaneous: SiN and C-N amination reactions 5. Conclusions and outlook

A decennary update on applications of metal nanoparticles (MNPs) in the synthesis of nitrogen- and oxygen-containing heterocyclic scaffolds

“…40 Recently, Gómez et al summarized the use of PdNPs for the synthesis of polyols via catalytic coupling and hydrogenation. 41 Dandia et al recently reported the synthesis of three-, ve-, six-and seven-membered ring systems using nanocatalysts. 42 Chaudret et al recently covered the role of several MNPs in s-H-H, s-C-H, and s-Si-H bond activation.…”

Palladium Oxide Nanoparticles: Preparation, Characterization and Catalytic Activity Evaluation

“…Since heterogeneous catalysis is based on processes taking place at the surface, the use of finely dispersed catalysts is often adopted in order to reduce the amount of material and maximize its catalytic effect [3,4]. For this purpose, palladium nanoparticles are widely used to catalyze organic reactions [5][6][7][8][9][10][11][12][13][14]. Similar to palladium, palladium(II) oxide (PdO) has also found applications in many catalytic processes [15][16][17][18], but few studies were carried out on the production of palladium oxide nanoparticles compared to the wide range of works concerning metallic palladium particles [19][20][21][22].…”

Tetraalkylammonium Functionalized Hydrochars as Efficient Supports for Palladium Nanocatalysts

“…Palladium nanoparticle‐based catalysts play a pivotal role in H 2 ‐based reactions, such as hydrodehalogenations of haloarenes and the reduction of unsaturated substrates, including oxidized nitrogen derivatives, especially for the production of anilines at industrial scale . This versatile reactivity offers great potential towards contaminated water/soil remediation via degradation of pollutants and environmentally friendly processes by means of selective catalytic reduction approaches precluding NO x emissions .…”