Meglumine sulfate-catalyzed one-pot green synthesis and antioxidant activity of α-aminophosphonates

Abstract

A green and efficient synthetic protocol has been developed for the synthesis of a new series of substituted diethyl(((2-methoxy-5-(trifluoromethyl)phenyl)amino)(phenyl)methyl)phosphonates via a one-pot three-component reaction of 2-methoxy-5-trifluoromethyl aniline with various aromatic-substituted aldehydes and diethyl phosphite using meglumine sulfate as an eco-friendly catalyst at room temperature under solvent-free conditions. The merits of this method are high product yield, short reaction time, easy workup, and purification. All the synthesized compounds were evaluated for the antioxidant activity by DPPH, NO, and H₂O₂ methods using ascorbic acid as a standard. The compounds 4a and 4g showed the highest antioxidant activity than that of the standard ascorbic acid.

Graphical Abstract

Keywords:

• α-Aminophosphonates
• antioxidant activity
• meglumine sulfate
• one-pot
• solvent-free

Acknowledgments

T. Sreekanth is thankful to the University Grants Commission (UGC), New Delhi, India for providing financial support through Senior Research Fellowship (File No: 21/12/2014(ii)EU-V dated 29/06/15); G. Mohan thanks the funding from DST-PURSE Centre, S.V. University, Tirupati, [SRF (File No. 17118-UGCIII(3)/DST-PURSE-2nd phase/2017, dated 23/08/2018)].

Additional information

Funding

T. Sreekanth is thankful to the University Grants Commission (UGC), New Delhi, for providing financial support through Senior Research Fellowship (File No: 21/12/2014(ii)EU-V dated 29/06/15); G. Mohan thanks the funding from S.V. University, Tirupati, [SRF (File No. 17118-UGC-III(3)/DST-PURSE-2nd phase/2017, dated 23/08/2018)]