Acceptorless dehydrogenation of alcohols to carboxylic acids by palladium nanoparticles supported on NiO: delving into metal–support cooperation in catalysis

Abstract

Pd nanoparticles (NPs) supported on NiO as an efficient heterogeneous catalyst for acceptorless dehydrogenation of primary alcohols to carboxylic acids with a low catalyst loading.

Ni(OH)2 nanoparticles as a recyclable catalyst in acceptorless dehydrogenation of alcohols to acids/acid salts under aerobic conditions

“…Although the yield of benzoic acid can be improved by employing a heterogeneous Pd/C catalyst, [24] it needs to carry out the reaction in reduced pressure to realize optimal yields of products and thus it provided an operational difficulty to perform the reaction. Moreover, the reaction can easily be carried out in the presence of catalytic systems such as ZnO, [26] in‐situ generated Ag nanoparticles, [29] magnetic Ag nanoparticles, [28] zeolite imidazolate framework‐8, Co‐clusters decorated with N‐doped carbon nanotube (Co/N‐CNTs), [27,33] palladium nanoparticles supported on NiO, [32] self‐supported Ru‐NHC single site catalyst [14k] in the presence of either NaOH or KOH base. Remarkably, a graphene‐supported Ru‐NHC catalytic system has been employed to synthesize a multitude of acids from corresponding alcohols in an aqueous basic medium [14l] .…”

Iridium Nanoparticles on NiO as Heterogeneous Catalysts for Acceptorless Dehydrogenation of Primary Alcohols with Tunable Product Selectivity

“…The nanostructured NiO-supported iridium catalyst (IrNP@NiO) was prepared via a wet chemical approach (Scheme 1) by a procedure previously reported by our group for the preparation of a conceptually similar Pd nanoparticle catalyst. 49 The transmission electron microscopy (TEM) images of the parent NiO material demonstrated formation of near-flake-like structures with a narrow size distribution, and the majority of the particles were within the size range of 20−30 nm (80−100 particles per site count) (Figure 1). High-resolution TEM (HR-TEM) micrographs of neat NiO and their corresponding selected area electron diffraction (SAED) patterns were found to be consistent with polycrystalline NiO nanoparticles.…”

“…A similar trend was also observed in the literature for a Pd/NiO catalyst. 49 Substrate Scope for the Dehydrogenation Reaction of Primary Alcohols to Acids. Intrigued by the above findings, we explored the ability of our catalytic system for dehydrogenation of a broad range of primary alcohols.…”

“…48 Recently, we demonstrated the catalytic activity of a Pd-based heterogeneous catalyst that showed a dramatic improvement in catalyst loading (0.08 mol % Pd) and substrate scope for the AD reactions of alcohols to afford carboxylic acids. 49 To further expand the scope of acceptorless dehydrogenation reactions, herein, we report the synthesis and characterization of a nanostructured iridium catalyst and its development as a recyclable heterogeneous catalyst for the selective conversion of primary alcohols to aldehydes or acids without the addition of any oxidant. The product selectivity is tuned to aldehydes in the absence of a base and to carboxylic acids in the presence of a base.…”

Cucurbit[6]uril supported β-Ni(OH)2 nanoparticles as a heterogeneous catalyst for the synthesis of quinazolines via acceptorless dehydrogenative coupling of alcohols with nitriles

“…36 Recently, nickel salts/complexes have been extensively used in o-arylation of esters, 37 hydrogenation, dehydrogenation, cyclization, cycloaddition, and multicomponent reactions. 38,39 Nickel nanoparticles and their oxides have emerged as efficient catalysts in hydrogenolysis, 40,41 dehydrogenation, 42 condensation reactions, 43,44 reduction reactions, 45 and C-C bond formation. [46][47][48] A perusal of the literature reveals that Ni(OH) 2 NPs have been used in the field of electrocatalysis, [49][50][51][52][53] photocatalysis, [54][55][56][57] supercapacitors, [58][59][60][61] and heterogeneous catalysis, [62][63][64] yet Ni(OH) 2 NPs remain relatively less explored in the arena of catalysis.…”