Enol phosphates from 3-diethylphosphonocoumarin: synthesis and transformations under phase-transfer conditions

Abstract

Enol phosphates were prepared from 3-diethylphosphonocoumarin under phase-transfer conditions as altered conditions for tandem hydrogenation / phosphorylation reactions. The optimized reaction conditions are characterized with high regioselectivity for O-phosphorylation and O-acylation. The newly synthesized enol phosphates were fully characterized by NMR Spectroscopic techniques and the single (Z)-isomers were assigned.

Graphical Abstract

Keywords:

• Coumarins
• enol phosphates
• phase-transfer conditions
• phosphorylation reactions
• tandem reactions

Acknowledgments

The authors would like to express their gratitude to Prof. Nestor A. Rodios from Laboratory of Organic Chemistry, Department of Chemistry, Aristotle University of Thessaloniki, for the initial NMR data and MS spectra. The authors wish to express their appreciation to Prof. Athanassios Giannis, University of Leipzig, Germany, for HRMS analyses.

Additional information

Funding

This work was supported by the Bulgarian National Science Fund under Grant KP-06-N-39/15 project “Dimeric coumarin structures – new synthetic approaches and quantum-chemical investigations.”