One-pot synthesis of amides via the oxidative amidation of aldehydes and amines catalyzed by a copper-MOF

Gut microbiome-derived hydrolases-an underrated target of natural product metabolism

In recent years, there has been increasing interest in studying gut microbiome-derived hydrolases in relation to oral drug metabolism, particularly focusing on natural product drugs. Despite the significance of natural product drugs in the field of oral medications, there is a lack of research on the regulatory interplay between gut microbiome-derived hydrolases and these drugs. This review delves into the interaction between intestinal microbiome-derived hydrolases and natural product drugs metabolism from three key perspectives. Firstly, it examines the impact of glycoside hydrolases, amide hydrolases, carboxylesterase, bile salt hydrolases, and epoxide hydrolase on the structure of natural products. Secondly, it explores how natural product drugs influence microbiome-derived hydrolases. Lastly, it analyzes the impact of interactions between hydrolases and natural products on disease development and the challenges in developing microbial-derived enzymes. The overarching goal of this review is to lay a solid theoretical foundation for the advancement of research and development in new natural product drugs and personalized treatment.

Metal-Organic Frameworks/Graphdiyne/Copper Foam Composite Membranes for Catalytic Applications

Graphdiyne (GDY) with a three-dimensional network structure was synthesized on a copper foam (CF) via an in situ Glaser-Hay coupling reaction. A metal-organic framework/GDY composite membrane was designed and synthesized for the first time. CF serves as a template and catalyst for the directed polymerization of GDY membranes. The catalytic activities of HKUST-1/GDY/CF membrane in wet peroxide oxidation of phenol, oxidation of benzyl alcohol, and ring opening of epoxide were studied. The composite membrane has the advantages of appropriateness for continuous operation, simple use process, easy recycling, high catalytic efficiency, etc. It was found that the incorporation of GDY can facilitate electron transfer and effectively improve the catalytic activity of HKUST-1 in membrane catalysis.

K2CO3-promoted synthesis of amides from 1-aryl-2,2,2-trifluoroethanones and amines under mild conditions

A base-promoted amidation of 1-aryl-2,2,2-trifluoroethanones with amines via Haller-Bauer reaction has been developed. In this reaction, the direct transformation of 1-aryl-2,2,2-trifluoroethanones into amides via C(O)-C bond cleavage occurs without the use of any stoichiometric chemical oxidants or transition-metal catalysts. A series of primary and secondary amines are shown to be compatible with this transformation, and several pharmaceutical molecules were synthesized.

Synthesis and characterization of rare earth/lithium complexes stabilized by ethylenediamine-bridged bis(phenolate) ligands and their activity in catalyzing amidation reactions

Rare earth/lithium complexes stabilized by ethylenediamine-bridged bis(phenolate) ligands have been synthesized and characterized. In addition to five rare earth/lithium amides isolated as major complexes, two other rare earth/lithium complexes bearing two phenolate ligands were also isolated. The activities of rare earth/lithium amides in catalyzing the amidation of aldehydes and amines were studied, which revealed that the yttrium/lithium complex was highly active for a wide range of substrates, generating 58 examples of amides in 42-99% yields under mild conditions (i.e., room temperature, 3-hour reaction time, additive-free). More importantly, this is the first example of rare earth-based catalysts capable of catalyzing the amidation of primary aliphatic amines.

Solvent- and additive-free oxidative amidation of aldehydes using a recyclable oxoammonium salt

A range of acyl azoles have been prepared from aromatic, heteroaromatic, and aliphatic aldehydes by means of an oxidative amidation reaction. The methodology employs a substoichiometric quantity of an oxoammonium salt as the oxidant. It avoids the need for additives such as a base, is run solvent-free, and the oxoammonium salt is recyclable.

Diamine-functionalized porous graphene oxide sheets decorated with palladium oxide nanoparticles for the oxidative amidation of aldehydes

C–N coupling between aldehydes and amines by ultra-small PdO NPs adorned diamine functionalized porous GO sheets as retrievable nano-catalyst.

Amide Bond Formation via Aerobic Photooxidative Coupling of Aldehydes with Amines Catalyzed by a Riboflavin Derivative

We report an effective, operationally simple, and environmentally friendly system for the synthesis of tertiary amides by the oxidative coupling of aromatic or aliphatic aldehydes with amines mediated by riboflavin tetraacetate (RFTA), an inexpensive organic photocatalyst, and visible light using oxygen as the sole oxidant. The method is based on the oxidative power of an excited flavin catalyst and the relatively low oxidation potential of the hemiaminal formed by amine to aldehyde addition.

Direct synthesis of amides and imines by dehydrogenative homo or cross-coupling of amines and alcohols catalyzed by Cu-MOF

Oxidative dehydrogenative homo-coupling of amines to imines and cross-coupling of amines with alcohols to amides was achieved with high to moderate yields at room temperature in THF using Cu-MOF as an efficient and recyclable heterogeneous catalyst under mild conditions. Different primary benzyl amines and alcohols could be utilized for the synthesis of a wide variety of amides and imines. The Cu-MOF catalyst could be recycled and reused four times without loss of catalytic activity.

Cu2O nanoparticles anchored on carbon for the efficient removal of propofol from operating room wastewater via peroxymonosulfate activation: efficiency, mechanism, and pathway

Anesthetic drug wastage has increasingly become the main resource of operating room sewage, which poses a great risk to the safety of humans and other organisms. Propofol is the most widely used anesthetic drug in the world, and also occupies the largest proportion of the total anesthetic wastage in the operating room. In this work, a 2D Cu₂O anchored carbon catalyst (Cu₂O@NC) was prepared by the assembly-pyrolysis process and successfully applied to peroxymonosulfate (PMS) activation. We took propofol as a typical example and investigated the removal activity through heterostructure-enhanced advanced oxidation processes (AOPs). Through the degradation process, propofol can be removed from 20 ppm to ultralow levels within 5 min using the PMS/Cu₂O@NC system. The degradation pathway of propofol was deduced through quantum chemical calculation and LC/GC-MS results. The final products were verified as CO₂ and H₂O. Moreover, sulfate radicals (SO₄˙⁻) proved to be the dominant reactive oxidation species by radical scavenger experiments and ESR results. In addition, it has great universality for various pharmaceuticals such as tetracycline (TC), amoxicillin (AMX), cephalexin (CPX), and norfloxacin (NFX). Our work provided the possibility to treat operation room sewage in a rapid, high-efficiency, and feasible way.

The 2D Cu₂O@NC catalyst obtained by thermal decomposition of MOF, could effectively enhance the propofol removal from wastewater by activating peroxymonosulfate in the advanced oxidation process.

Covalent functionalization of carbon materials with redox-active organic molecules for energy storage

Carbon-based materials (CBMs) have shown great versatility because they can be chemically combined with other materials for various applications. Chemical modification of CBMs can be achieved via covalent or non-covalent interactions. Non-covalent interactions are weak and fragile, causing structural change and molecule dissociation. Therefore, in this review, we summarize the covalent modification of CBMs via organic chemistry techniques, aiming at forming more robust and stable CBMs. Besides, their application as electrode materials in energy storage systems is also within the scope of this review. Covalent binding of redox-active organic molecules with CBMs improves the transfer rate of electrons and prevents the dissolution of redox-active molecules, resulting in good conductivity and cycle life. Numerous papers on the functionalization of CBMs have been published to date, but some of them lack scientific evidence and are unable to understand from chemistry viewpoint. Reliable articles with adequate evidence are summarized in this review from a synthetic chemistry viewpoint.

Oxidative amidation by Cu(ii)–guanidine acetic acid immobilized on magnetized sawdust with eggshell as a natural base

Copper(ii)–guanidine acetic acid complex was immobilized on the surface of magnetized raw waste sawdust (SD) as an abundant natural biopolymer and employed as an efficient and recoverable catalyst in oxidative amidation reaction, while waste eggshell (ES) powder was used as a low-cost solid base.