Reusable zinc oxide nanoflowers for the synthesis of α-aminophosphonates under solvent-free ultrasonication

Abstract

A simple wet chemical method is used to prepare zinc oxide nanoflowers (ZnO NFs) which were subjected to various characterization techniques such as XRD, FTIR, UV–Vis, FE-SEM, and XPS. XRD pattern indicates pure, crystalline, and monodispersed form with hexagonal wurtzite phase. The 3-D flower shape morphology with hexagonal ZnO nanorods was confirmed in FE-SEM. The synthesized ZnO NFs was used to study catalytic behavior in Kabachnik–Fields reaction under controlled ultrasound cavitation technique. High surface-to-volume ratio of ZnO NFs and the effect of ultrasonication enhances the yield of α-aminophosphonate. The catalyst was recycled and reused four times without any significant loss of its catalytic activity. Moreover, existing method becomes attractive and practical due to its easy, clean, fast, cost-effective, and eco-friendly procedure.

Graphical Abstract

Keywords:

• Kabachnik–Fields reaction
• reusability
• solvent-free
• ultrasonication
• ZnO nanoflowers

Acknowledgments

One of the authors (Sarika Rasal) is thankful to DST-PURSE, New Delhi for award of research fellowship. We are also thankful to Microanalytical Laboratory, Department of Chemistry and University of Mumbai for providing characterization facilities.