Thallium(III) p-Tosylate Mediated Oxidative 2,3-Aryl Rearrangement: A New Useful Route to Ipriflavone and Its Analogs

Abstract

A new route for the synthesis of ipriflavone, an antiosteoporotic agent, is described that has four steps and 60% yields starting from resacetophenone (2). The key step of the present methodology is thallium(III) p-tosylate mediated oxidative 2,3-aryl rearrangement of flavanone to generate the isoflavone ring system of ipriflavone in a highly efficient manner.

Keywords:

• Flavanones
• ipriflavone
• isoflavones
• oxidative rearrangement
• thallium(III) p-tosylate

ACKNOWLEDGMENTS

The authors are grateful to the International Foundation of Science, Sweden, and the State Committee on Science, Technology, and Environment, Thiruvananthapuram, Government of Kerala, India, for financial support.