Efficient synthesis of xanthene derivatives using carboxyl functionalized graphene quantum dots as an acidic nano-catalyst under microwave irradiation

Abstract

Carboxyl functionalized graphene quantum dots (CGQDs) was applied as a highly efficient and green acidic catalyst for the coupling reaction of 2-naphthole and benzaldehyde derivatives for the preparation of 14H-dibenzo xanthene derivatives, under solvent-free microwave irradiation conditions. The structures of the 14H-dibenzo xanthene derivatives were confirmed by FT-IR, 1 H-NMR and 13 C-NMR spectroscopic techniques. The structure of catalyst was also confirmed by FT-IR, XRD, TEM and PL techniques. In order to demonstrate the positive impact of CGQDs catalyst, the reaction times and yields of the products were compared with similar products which have been reported previously. 14H-Dibenzo xanthene derivatives were synthesized in simple procedure, good to excellent yields via the present procedure.

Fabrication of poly(vinyl alcohol)‐graphene quantum dots coated with poly(3,4‐ethylenedioxythiophene) for supercapacitor

“…The peaks of PVA are still observable for samples containing PEDOT indicating that the PVA nanofibers still present after the electrodeposition of PEDOT. The FTIR spectrum of GQD shows the presence of two major peaks of oxygen functional groups appeared at 1730 and 3345 cm −1 , which corresponding to CO and OH group . The adsorption bands of PEDOT were observed at 1473, 630, 1315, and 1033 cm −1 that assigned to the CC, CS, CC, and CO stretching vibrations from the thiophene and ethylenedioxy group of PEDOT .…”

“…The FTIR spectrum of GQD shows the presence of two major peaks of oxygen functional groups appeared at 1730 and 3345 cm 21 , which corresponding to C@O and OAH group. 32 The adsorption bands of PEDOT were observed at 1473, 630, 1315, and 1033 cm 21 that assigned to the C@C, CAS, CAC, and CAO stretching vibrations from the thiophene and ethylenedioxy group of PEDOT. 33,34 The main peaks of PEDOT still can be observed in the spectrum of PVA/PEDOT and PVA-GQD/PEDOT, indicating that PEDOT was successfully electrodeposited on the electrospun nanofibers.…”

Graphene quantum dots for energy storage and conversion: from fabrication to applications

“…65 Mohammad-Rezaei et al oxidized rGO with nitric acid and sulfuric acid under microwave conditions. 66 The carboxyl functionalized GQDs they obtained were used to catalyse the coupling reaction of 2-naphthol with a benzaldehyde derivative (Fig. 4b).…”

Boron/Nitrogen Co-doped carbon quantum dots as a high sensitive and selective fluorescent sensor for PO43- detection

“…15 Phosphate ion detection have also been reported using silver nanoclusters/metal-organic shell composite in aqueous solutions. 16 In continuation of our interest in preparation and using CQD and modified CQD as a reagent and/or catalyst in chemical reactions, [17][18][19] we decided to prepare B-doped CQD and examine its applicability for the sensing of some important anions.…”