Exploiting Chloroform-COware Chemistry for Pd-Catalyzed Carbonylation of Naturally Occurring and Medicinally Relevant Phenols

In this study, a ligand-free palladium-catalyzed carbonylation of phenols is conducted under ambient conditions, utilizing the "Chloroform-COware" chemistry. The developed methodology enables the conversion of diverse medicinally relevant phenols, encompassing both natural and synthetic derivatives, into their respective aryl ester counterparts. This transformation is achieved through the reaction with a broad spectrum of aryl and heteroaryl iodides. The protocol is characterized by its simplicity, generality, and wide substrate scope, delivering bioactive aryl ester derivatives in good to excellent yields. A direct comparison with the one-pot approach, resulting in poor yields of aryl esters, highlights the superior efficiency of the two-chamber setup (COware). Moreover, we successfully applied this two-chamber technique for gram-scale synthesis and postmodification of the synthesized ester to a pharmaceutically important benzocoumarin core.

Photo-Induced Carbonylation of Aryl Bromides for the Synthesis of Aryl Esters and Amides Under Transition Metal-Free Conditions

In this work, we developed a photo-induced carbonylation of aryl bromides under transition metal-free conditions. The reaction shows good activity with alcohol and amine nucleophiles. Various esters and amides were formed from aryl halides and alcohols and amines under mild conditions in moderate to good yields.

Tandem utilization of CO2 photoreduction products for the carbonylation of aryl iodides

Photocatalytic CO₂ reduction reaction has been developed as an effective strategy to convert CO₂ into reusable chemicals. However, the reduction products of this reaction are often of low utilization value. Herein, we effectively connect photocatalytic CO₂ reduction and amino carbonylation reactions in series to reconvert inexpensive photoreduction product CO into value-added and easily isolated fine chemicals. In this tandem transformation system, we synthesize an efficient photocatalyst, NNU-55-Ni, which is transformed into nanosheets (NNU-55-Ni-NS) in situ to improve the photocatalytic CO₂-to-CO activity significantly. After that, CO serving as reactant is further reconverted into organic molecules through the coupled carbonylation reactions. Especially in the carbonylation reaction of diethyltoluamide synthesis, CO conversion reaches up to 85%. Meanwhile, this tandem transformation also provides a simple and low-cost method for the ¹³C isotopically labeled organic molecules. This work represents an important and feasible pathway for the subsequent separation and application of CO₂ photoreduction product.

Palladium nanoparticles on a pyridinium supported ionic liquid phase: a recyclable and low-leaching palladium catalyst for aminocarbonylation reactions

SILP catalyst with grafted pyridinium ions was used for either mono- or double carbonylation depending on the reaction conditions. Good recyclability and low palladium loss were observed during the synthesis of pharmaceutically active compounds.

Synthesis and Structural Analysis of Palladium(II) Complexes Containing Neutral or Anionic C 2-Symmetric Bis(oxazoline) Ligands: Effects of Substituents in the 5-Position

A series of neutral and cationic palladium(II) complexes containing C ₂-symmetric bis(oxazoline) (BOX) ligands, (BOX)PdCl₂ (2a-d), (BOX)Pd(Me)Cl (3a-d), and [(BOX)PdMe(2,6-Me₂C₅H₃N)]⁺PF₆ ^- (4a-d) [BOX: 2,2'-(2-propylidene)bis{(4R)-4-phenyl-5,5-dimethyl-2-oxazoline}, 2,2'-methylenebis{(4R)-4-phenyl-5,5-dimethyl-2-oxazoline}, 2,2'-methylenebis{(4R)-4,5,5-triphenyl-2-oxazoline}, and 2,2'-methylenebis{(4R,5S)-4,5-diphenyl-2-oxazoline}], were prepared, and their structures were determined by X-ray crystallography. It was found that substituents at the 5-position (Ph, Me) in addition to substituents on the bridgehead carbon directly affect the structure around palladium, especially the BOX bite angle and the dihedral angles between the phenyl rings at the 4-position and the N₂Pd plane. Treatment of the bridged methylene proton in the BOX ligand (1b-d) with KH afforded the anionic BOX ligand; also, the neutral Pd complexes, (BOX)PdMe(2,6-Me₂C₅H₃N) (5b-d), could thus be prepared by reaction with Pd(Me)Cl(cod) (cod = 1,5-cyclooctadiene); 5b-d showed strong coordination to Pd, as demonstrated by X-ray crystallographic analysis.

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

Silica modified with organic dicationic moieties proved to be an excellent support for palladium catalysts used in the aminocarbonylation of aryl iodides.