LiBr/β-CD/IBX/H₂O-DMSO: A new approach for one-pot biomimetic regioselective ring opening of chalcone epoxides to bromohydrins and conversion to 1,2,3-triketones

ABSTRACT

Highly regioselective ring cleavage of chalcone epoxides to bromohydrins has been carried out in good yields with LiBr in the presence of β-CD using DMSO-H₂O as solvent system. The ring-opened product, i.e., bromohydrin, was well adapted to IBX-mediated oxidation in such a fashion that the bromohydrins are transformed to their corresponding 1,2,3-triketones in moderate-to-good yields in one pot.

GRAPHICAL ABSTRACT

KEYWORDS:

• Bromohydrin
• chalcone epoxide
• IBX
• triketones
• β-cyclodextrin

Acknowledgments

The authors wish to express their gratitude to DST, New Delhi, for providing HRMS and NMR facility and CSIR, New Delhi, for awarding SRF to S. Kumar and N. Verma.