Graphene oxide immobilized 2-morpholinoethanamine as a versatile acid–base catalyst for synthesis of some heterocyclic compounds and molecular docking study

Abstract

In this study, a new heterogeneous catalyst was synthesized based on graphene oxide (GO) as a natural material. On the surface of nanosheet graphene oxide, 2-Morpholinoethanamine was immobilized using a non-toxic, green, and simple method. This resulted in the preparation of a bifunctional acid–base nanocatalyst. The synthesized composite was fully characterized using various methods, including Fourier transform infrared spectrometry (FT-IR), scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDS), mapping, Raman spectroscopy, X-ray diffractometry (XRD), thermogravimetric analysis (TGA), and CHN elemental analysis. The catalytic reactivity of GO-mor was investigated in the one-pot synthesis of some benzo[b]pyran, pyrano[3,2-c]chromene, and polyhydroquinoline derivatives, yielding good efficiency and short reaction times. In addition, several recent studies have shown that some derivatives of pyran, chromene, and quinoline have remarkable anti COVID activity. Particularly, COVID-19 3CLpro/Mpro is considered a potential target for the treatment of this virus. For this purpose, docking models were constructed using the corresponding crystal structures with the synthesized derivatives. Based on the docking score and similarity of the binding mode to remdesivir and elvitegravir (the only approved drugs for the treatment of COVID-19), A2, B1, and C4 were selected as promising candidates for further research.

Tuning Acid–Base Chemistry at an Electrified Gold/Water Interface

“…Acid–base equilibrium is one of the most ubiquitous reactions in chemistry and plays an essential role in both fundamental research and technological applications. − Especially in the realm of electrochemistry, acid–base reactions are pivotal since proton transfer is one of the most common processes in electrocatalysis that often involves proton-coupled electron transfer reactions. − It determines the state and adsorption of reactive molecules, as well as the pH effects on electrochemical reactions, e.g., in water splitting and CO 2 reduction. , Therefore, the acid dissociation constant (p K a ) of molecules at electrified metal/water interfaces is a key parameter for understanding and optimizing the electrocatalytic performance.…”