Platinum(II)-Catalyzed Novel Synthesis of 3,4-Fused Furans

Abstract

A novel synthesis of 3,4-fused furans (both tricyclic and bicyclic) through platinum-catalyzed cyclization of 3-(2-formylcycloalkenyl)-acrylic amides 2 in methanol is described (up to 90% yield). Tricyclic 3,4-fused dihydrofuran derivatives were also obtained via reductive cyclization of 2. The substrates 2 were obtained from β- bromovinyl aldehydes by a Pd-catalyzed Heck reaction.

GRAPHICAL ABSTRACT

Keywords:

• 3-(2-Formylcycloalkenyl)-acrylic amide
• 3,4-fused furans
• Heck reaction
• Michael addition

ACKNOWLEDGMENTS

We are grateful to the Chemistry Department of Jadavpur University for the facilities for NMR spectroscopy, Atanu Jana for his expertise in x-ray crystollagraphy, and Arup Kumar Adak and Biswanath Mondal for constant inspiration.

SUPPORTING INFORMATION

Electronic supplementary information (ESI) (¹H and ¹³C spectra of representative compounds) for this article and can be accessed on the publisher’s website.