Syntheses and utilizations of pyrroline and tetrahydropyridine nitroxide-based phosphonate esters, a phosphate ester and a bisphosphonate

Abstract

Five- and six-membered cyclic nitroxide-based allylic phosphonate esters, α-ketophosphonate esters were obtained from the corresponding paramagnetic allyl bromides and acyl chlorides respectively via the Arbuzov reactions. The α-hydroxyphosphonate esters were accessed by Pudovik reactions from the corresponding paramagnetic ketones and aldehydes. The β-ketophosphonate esters were obtained from the appropriate 1-alkynylphosphonate esters via PdCl₂-catalyzed hydration. The synthesis of an allylic phosphate ester and a paramagnetic geminal bisphosphonate was also reported.

Graphical Abstract

Keywords:

• Arbuzov reaction
• acetylenes
• nitroxides
• phosponates
• Pudovic reaction

Acknowledgments

The study was financed by the Higher Education Institutional Excellence Programme of the Ministry of Human Capacities in Hungary within the framework of the 2020-4.1.1.-TKP2020 Innovation for sustainable and healthy living and environment thematic programme of the University of Pécs.