Pd-Catalyzed Oxidative Aminocarbonylation of Arylboronic Acids with Unreactive Tertiary Amines via C-N Bond Activation

Pd/C-Catalyzed Oxidative Aminocarbonylation of Aryldiazonium Tetrafluoroborate Salts through sp3CN Bond Activation of Inert Tertiary Amines to Tertiary Amides

Aryldiazonium tetrafluoroborate salts are highly accessible from readily available and inexpensive amines, and by realizing these advantages, an efficient protocol is developed that employs aryldiazonium tetrafluoroborate salts as an effective electrophile for oxidative aminocarbonylation with unreactive tertiary amines. In this, molecular oxygen has been used as an ideal and green oxidant, which activates the inert CN bond. Various derivatives of aryldiazonium tetrafluoroborate salts are prepared, which include different electron-withdrawing and electron-donating group substituents. This protocol utilizes Pd/C as a heterogeneous catalyst, which is smoothly recyclable. Moreover, this developed method is ligand and cocatalyst free, and it does not require any base to activate the amines as nucleophile, and the new process effectively provides a mild pathway toward a variety of tertiary amide moieties with significant yield. This way, the potent protocol is economical, simple, recyclable, and operates at milder conditions and contributes toward valuable products that are vital in an industrial domain.

Copper catalyzed carbon-selenium bond formation via the coupling reaction of aryl halides, phenylboronic acid and Se

This is the first report for C-Se bond formation involving the reaction of aryl halides with arylboronic acid and selenium powder to synthesis of unsymmetrical diaryl selenides in the presence of CuI as a homogeneous catalyst. A wide range of aryl halides react with various substituted groups under optimal conditions to provide the desired unsymmetrical diaryl selenides with good to high yields. Also, the same reactions were investigated in the presence of M-MCF@Gua-Cu as a reusable magnetic nanocatalyst under optimal conditions. The M-MCF@Gua-Cu catalyst allows for simpler (easy work-up) and greener methodology. In addition, the advantages of the presented method include the use of arylboronic acid/Se as a safe and cost-effective arylselenating system, the simplicity of operation, and green and cheap solvent.

Tandem Electro-Thermo-Catalysis for the Oxidative Aminocarbonylation of Arylboronic Acids to Amides from CO2 and Water

Direct CO2 electroreduction to valuable chemicals is critical for carbon neutrality, while its main products are limited to simple C1 /C2 compounds, and traditionally, the anodic O2 byproduct is not utilized. We herein report a tandem electrothermo-catalytic system that fully utilizes both cathodic (i.e., CO) and anodic (i.e., O2 ) products during overall CO2 electrolysis to produce valuable organic amides from arylboronic acids and amines in a separate chemical reactor, following the Pd(II)-catalyzed oxidative aminocarbonylation mechanism. Hexamethylenetetramine (HMT)-incorporated silver and nickel hydroxide carbonate electrocatalysts were prepared for efficient coproduction of CO and O2 with Faradaic efficiencies of 99.3 % and 100 %, respectively. Systematic experiments, operando attenuated total reflection surface-enhanced Fourier transform infrared spectroscopy characterizations and theoretical studies reveal that HMT promotes *CO2 hydrogenation/*CO desorption for accelerated CO2 -to-CO conversion, and O2 inhibits reductive deactivation of the Pd(II) catalyst for enhanced oxidative aminocarbonylation, collectively leading to efficient synthesis of 10 organic amides with high yields of above 81 %. This work demonstrates the effectiveness of a tandem electrothermo-catalytic strategy for economically attractive CO2 conversion and amide synthesis, representing a new avenue to explore the full potential of CO2 utilization.

Carbonylative Self-Coupling of Aryl Boronic Acids Using a Confined Pd Catalyst within Melamine Dendron and Fibrous Nano-Silica: A CO Surrogate Approach

Development of heterogeneous catalysts with tunable activity and selectivity has posed a persistent challenge. This study addresses this challenge by fabricating a hybrid environment through the combination of mesoporous silica and N-rich melamine dendron via covalent grafting, allowing for controllable growth and encapsulation of Pd NPs. This catalyst presented an excellent catalytic activity for the oxidative carbonylative self-coupling of aryl boronic acids to afford symmetric biaryl ketones using N-formyl saccharin as a sustainable solid CO source and Cu as a co-catalyst.

KOH-promoted cascade C-Cl bond activation and amidation of trichloromethyl aromatic compounds with formamides in water

A KOH-promoted cascade C-Cl bond activation and amidation of trichloromethyl aromatic compounds with formamides using water as a solvent has been developed. This methodology suggested an alternative synthetic approach for the synthesis of aryl amide compounds in the absence of catalysts, additives and organic solvents. In addition, the yields of gram-scale reactions are good and provide a basis for synthetic application.

Organic photoredox catalyzed dealkylation/acylation of tertiary amines to access amides

A mild metal-free C-N bond activation strategy for the direct conversion of inert tertiary amines with acyl chlorides into tertiary amides via organic photoredox catalysis is presented. In this protocol, a novel organic photocatalyst (Cz-NI-Ph) that showed excellent catalytic performance during C-N bond cleavage is developed. Moreover, this reaction features green and mild conditions, broad substrate scope, and readily available raw materials.

Visible-light-mediated amidation from carboxylic acids and tertiary amines via C-N cleavage

In this communication, we report a photocatalyzed amidation strategy from carboxylic acids and tertiary amines through the C-N bond cleavage. A wide scope of structurally diverse carboxylic acids participates smoothly...

Tunable Pd/C-catalyzed Oxidative Alkoxycarbonylation /Aminocarbonylation of Aryl hydrazines with Alcohols / Inert Tertiary amines through C−N Bond Activation

We report Pd/C-catalyzed oxidative aminocarbonylation and alkoxycarbonylation of unactiavated aryl hydrazines. This protocol employs inert tertiary amines as an aminal source and arylhydrazines via oxidative sp3 and sp2 C−N bond...