Design and introduction of quaternary ammonium hydroxide-functionalized graphene oxide quantum dots as a pseudo-homogeneous catalyst for epoxidation of α,β-unsaturated ketones

Mohammed Salim Mohammed; Homa Targhan; Kiumars Bahrami

doi:10.1038/s41598-023-34635-5

Design and introduction of quaternary ammonium hydroxide-functionalized graphene oxide quantum dots as a pseudo-homogeneous catalyst for epoxidation of α,β-unsaturated ketones

Sci Rep. 2023 May 19;13(1):8140. doi: 10.1038/s41598-023-34635-5.

Authors

Mohammed Salim Mohammed¹, Homa Targhan², Kiumars Bahrami^{3

4}

Affiliations

¹ Nanoscience and Nanotechnology Research Center (NNRC), Razi University, Kermanshah, 67144-14971, Iran.
² Department of Organic Chemistry, Faculty of Chemistry, Razi University, Kermanshah, 67144-14971, Iran.
³ Nanoscience and Nanotechnology Research Center (NNRC), Razi University, Kermanshah, 67144-14971, Iran. kbahrami2@hotmail.com.
⁴ Department of Organic Chemistry, Faculty of Chemistry, Razi University, Kermanshah, 67144-14971, Iran. kbahrami2@hotmail.com.

Abstract

In present work, design and synthesis of a novel pseudo-homogeneous catalyst is described. For this purpose, amine-functionalized graphene oxide quantum dots (N-GOQDs) were prepared from graphene oxide (GO) by a facile one-step oxidative fragmentation approach. The prepared N-GOQDs were then modified with quaternary ammonium hydroxide groups. Various characterization techniques clearly revealed that the quaternary ammonium hydroxide-functionalized GOQDs (N-GOQDs/OH^-) have been successfully synthesized. TEM image revealed that the GOQDs particles are almost regularly spherical in shape and mono-dispersed with particle sizes < 10 nm. The efficiency of the synthesized N-GOQDs/OH^- as a pseudo-homogeneous catalyst in epoxidation of α,β-unsaturated ketones in the presence of aqueous H₂O₂ as an oxidant at room temperature was investigated. The corresponding epoxide products were obtained in good to high yields. This procedure has the advantages of a green oxidant, high yields, involvement of non-toxic reagents and reusability of the catalyst without discernible loss in activity.