Sulfonated reduced graphene oxide as a highly efficient catalyst for direct amidation of carboxylic acids with amines using ultrasonic irradiation

Ultrason Sonochem. 2016 Mar:29:371-9. doi: 10.1016/j.ultsonch.2015.10.009. Epub 2015 Oct 22.

Abstract

Sulfonated reduced graphene oxide nanosheets (rGO-SO3H) were prepared by grafting sulfonic acid-containing aryl radicals onto chemically reduced graphene oxide (rGO) under sonochemical conditions. rGO-SO3H catalyst was characterized by Fourier-transform infrared (FT-IR) spectroscopy, Raman spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and X-ray photoelectron spectroscopy (XPS). rGO-SO3H catalyst was successfully applied as a reusable solid acid catalyst for the direct amidation of carboxylic acids with amines into the corresponding amides under ultrasonic irradiation. The direct sonochemical amidation of carboxylic acid takes place under mild conditions affording in good to high yields (56-95%) the corresponding amides in short reaction times.

Keywords: Amines; Carboxylic acids; Direct amidation; Solid acid catalyst; Sonochemical reaction; Sulfonated reduced graphene oxide.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amides / chemistry*
  • Amines / chemistry*
  • Carboxylic Acids / chemistry*
  • Catalysis
  • Graphite / chemistry*
  • Kinetics
  • Nanostructures / chemistry
  • Oxidation-Reduction
  • Oxides / chemistry*
  • Sulfonic Acids / chemistry*
  • Ultrasonic Waves*

Substances

  • Amides
  • Amines
  • Carboxylic Acids
  • Oxides
  • Sulfonic Acids
  • Graphite