Hypervalent iodine promoted transformation of 4H-chromenes into dihydrofurans and 2H-chromenes

Abstract

A novel protocol to synthetic transformation of 4H-chromenes into dihydrofurans (3) and 2H-chromenes (11) promoted by hypervalent iodine has been accomplished in a one-pot reaction at ambient temperature. Dihydrofurans are exclusively formed under basic reaction conditions, whereas, 2H-chromenes are the products under acidic condition. Simple reaction conditions with a broad substrate scope inclusive of various heterocycles and high yields are the attractive features of this protocol.

Graphical Abstract

Keywords:

• 1,3-Diones
• hypervalent iodine
• 2H-chromenes
• 4H-chromenes
• dihydrofurans

Acknowledgements

We gratefully acknowledge the help received from Centre for NMR & Structural Chemistry and Analytical Chemistry & Mass Spectrometry, CSIR–IICT.

Additional information

Funding

We are grateful to SERB-DST, New Delhi, for financial support (grant no. EEQ/20l6/000066) and we thank director CSIR-IICT for the support (IICT/pubs./2019/333).