In situ generated Pd(0) nanoparticles stabilized by bis(aryl)acenaphthenequinone diimines as catalysts for aminocarbonylation reactions in water

Abstract

Aminocarbonylation of aryl iodides with aromatic and aliphatic amines, leading to formation of the corresponding amides, was efficiently carried out in water under 1 atm of CO using palladium nanoparticles (Pd NPs) formed in situ from [PdCl2(Ar2-BIAN)] complexes. The role of Ar2-BIAN ligands in the stabilization of Pd NPs was evidenced. The nature of the catalytically active species was confirmed by poisoning experiments, which highlighted that the catalyst is actually in the form of Pd NPs rather than soluble palladium complexes. In the aminocarbonylation of iodobenzene with substituted anilines good yields of amides were obtained, although the activity was depleted by the presence of substituents in the ortho positions of the aniline. On the other hand, in the reaction with aliphatic amines α-ketoamides were formed in addition to the amides. The selectivity towards α-ketoamides was increased by increasing the CO pressure to 10 atm, at equimolar amounts of PhI and amine. Pd NPs were successfully recovered after the catalytic reaction and recycled in five subsequent runs with only a marginal loss of activity after the fourth cycle

A rare example of the in situ formation of palladium nanoparticles: The emergence of catalytically active palladium nanoparticles from Pd (II) phosphine complexes in the Suzuki–Miyaura coupling reaction

“…Some examples can be found in the literature indicating that metal complexes, especially those with N and/or O donors, can transform into metal NPs in the reaction medium and that catalytic activity is carried out on these NPs via heterogeneous catalysis. [8,26,27] In all these studies, the formation of a dark suspension during the reaction, the stopping or slowing of the reaction with the addition of Hg(0), and the reusable nature of the recovered catalyst are all noted. [4,8] Although the dark suspension formation during the catalytic activity tests was observed in this study, other features such as Hg(0) test and reusability should be checked as well.…”

Alkyl Levulinates and 2-Methyltetrahydrofuran: Possible Biomass-Based Solvents in Palladium-Catalyzed Aminocarbonylation

“…However, an efficient homogeneous CC coupling, as well as an aminocarbonylation reaction, are often restricted, due to the limited solubility of reagents (substrates, amine nucleophiles) and amide products or the decomposition of the catalyst. Consequently, many more heterogeneous [ 16 , 17 , 18 , 19 , 20 , 21 ] or biphasic [ 22 ] aminocarbonylation processes have been described than homogeneous processes [ 23 , 24 , 25 ]. Additionally, it has been described by our research group that water can act as an O -nucleophile during aminocarbonylative conditions, resulting in the formation of carboxylic acid when low-reactive nucleophile reaction partners are used [ 26 ].…”

Novel synthesis of oxoacetamides via reaction of salicylaldehyde and isocyanide under mild reaction condition

“…Due to the chemical and biological value of α-ketoamides, various synthetic methods have been introduced and reported for the synthesis of this class of products over the past decades [2,14,15,16]. The methods that have been introduced so far for the synthesis of this valuable scaffold describe as following and an overview of the newest and important methods is outlined in Scheme 1.…”