The Michaelis–Becker Reaction in Phosphonium and Imidazolium Ionic Liquids

Abstract

The Michaelis–Becker reaction was performed in imidazolium ionic liquids using sodium hydroxide as base or sodium dialkylphosphites with good yield and selectivities. The analogous reaction performed in phosphonium ionic liquids resulted in decomposition to phosphine oxides.

Keywords:

• Imidazolium
• ionic liquid
• Michaelis–Becker
• phosphonium

Acknowledgments

We would like to acknowledge the National Science Foundation (NSF, Grant No. DUE-0535957) and the Motorola Foundation for financial support. We would also like to thank R. Hartsock, W. D. Stegbauer, and R. Barnum for early observations and preliminary data.

Notes

^a Isolated yields.

^b Sodium organophosphonates were pre-prepared from Na metal prior to use.

^{c 31}P NMR spectra were recorded at 161.9 MHz in CDCl₃ and referenced to external H₃PO₄.