Mono- and double carbonylation of aryl iodides with amine nucleophiles in the presence of recyclable palladium catalysts immobilised on a supported dicationic ionic liquid phase

Abstract

Silica modified with organic dicationic moieties proved to be an excellent support for palladium catalysts used in the aminocarbonylation of aryl iodides. By an appropriate choice of the reaction conditions, the same catalyst could be used for selective mono-or double carbonylations leading to amide and aketoamide products, respectively. The best catalyst could be recycled for at least 10 consecutive runs with a loss of palladium below the detection limit. By the application of the new support, efficient catalyst recycling could be achieved under mild reaction conditions (under low pressure and in a short reaction time). Palladium-leaching data support a mechanism with dissolution-re-precipitation of the active palladium species. † Electronic supplementary information (ESI) available: Preparation of the catalysts, general procedure for aminocarbonylation reactions, 29 Si CP MAS NMR spectrum of 3, TEM images and XPS spectra of catalysts, data of recycling experiments with CAT-1 and CAT-2, characterisation of products, and 1 H and 13 C-NMR spectra of isolated products, references. See

27 Years of Catalytic Carbonylative Coupling Reactions in Hungary (1994–2021)

“…By an appropriate choice of the reaction conditions, the same catalyst could be used for selective mono-or double carbonylations leading to amide and α-ketoamide products, respectively. The best catalyst could be recycled for at least 10 consecutive runs with a loss of palladium below the detection limit [107]. The efficiency of a palladium catalyst, immobilized on a supported ionic liquid phase (SILP) with adsorbed 1-butyl-4-methylpyridinium chloride (Figure 22), was scrutinized in aminocarbonylation reactions.…”

Pd(triNHC)‐catalyzed Double Carbonylation of Aryliodides With Amines: The Effect of triNHC Ligands

“…The palladium‐catalyzed carbonylation of amines with aryl halides has been intensively studied to form synthetically valuable α‐ketoamides; the choice of palladium catalysts and the reaction optimization were critical to selectivity forming α‐ketoamides 1–16 . Due to the abundance of α‐ketoamides in natural products and pharmaceuticals, 17 efficient and selective catalytic conditions for forming α‐ketoamides are attractive.…”

“…The palladium-catalyzed carbonylation of amines with aryl halides has been intensively studied to form synthetically valuable α-ketoamides; the choice of palladium catalysts and the reaction optimization were critical to selectivity forming α-ketoamides. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] Due to the abundance of α-ketoamides in natural products and pharmaceuticals, 17 efficient and selective catalytic conditions for forming α-ketoamides are attractive. Based on prior work regarding the carbonylative coupling of amines and aryl halides, the effect of ligands, bases, and CO pressure are key factors that control the selectivity of α-ketoamides over amides; the double carbonylation forms α-ketoamides, and amides are produced by a single CO insertion (Figure 1).…”

“…It has been previously reported that electron-rich t Bu 3 P and N-heterocyclic carbene (NHC) promote the double carbonylation to form α-ketoamides (Scheme 1). 8,12,13 In this work, we present a new palladium catalyst modified with a tridentate triNHC ligand for the synthesis of α-ketoamides (Scheme 1). The electronic properties of the triNHC ligand are reflected in the carbonylation of amines.…”

Palladium nanoparticles stabilized by chitosan/PAAS nanofibers: A highly stable catalyst for Heck reaction

“…Moreover, due to the harsh reaction condition (e.g. polar solvents and high temperature), the aggregation and leaching of Pd NPs in catalysis procedure would reduce its catalytic activity . Therefore, there is an urgent need to develop a cost‐effective process to fabricate high performance nanomaterials to stabilize the Pd NPs.…”