An Efficient Synthesis of Naphtho[2,3-b]furan-4,9-diones via Visible-Light-Mediated [3+2] Cycloaddition Reaction

Abstract

Naphtho[2,3-b]furan-4,9-dione is an important privileged structural motif which is present in natural products, drugs, and drug candidates. Herein, visible-light-mediated [3+2] cycloaddition reaction for the synthesis of naphtho[2,3-b]furan-4,9-diones and dihydronaphtho[2,3-b]furan-4,9-diones has been developed. Under environmentally friendly conditions, a variety of title compounds were delivered in good yields. This new protocol shows excellent regioselectivity and remarkable functional group tolerance. This approach provides a powerful, green, efficient, and facile means to expand the structural diversity of naphtho[2,3-b]furan-4,9-diones and dihydronaph-tho[2,3-b]furan-4,9-diones as promising scaffolds for novel drug discovery.

Visible-Light-Mediated Catalyst-Free [2+2] Cycloaddition Reaction for Dihydrocyclobuta[b]naphthalene-3,8-diones Synthesis under Mild Conditions

“…[2+2] cycloaddition reaction for the synthesis of DHCBNDOs. To supplement our initial research in the synthesis of tricyclic or polycyclic fused organic compounds using photocatalytic reactions [26][27][28][29], we would like to report a green, facile and visible-light-mediated [2+2] cycloaddition reaction for DHCBNDOs synthesis at ambient temperature. We believe this approach not only represents a mild, clean and economical method for the preparation of DHCBNDOs, but also exhibits promising prospects in synthetic chemistry, such as constructing organic molecules of complex structures.…”

“…Some great improvements via [2+2] photocycload made by Zhang's (high-pressure mercury lamp) [15] and Shah's (visib [2+2] cycloaddition) groups [25]. However, the reported methods severe unfriendly conditions, such as heating, high-pressure mercury lamp, acid idants, which created some drawbacks in these strategies in terms of en tection, safety, economy, reaction selectivity and functional group tole significant progress has been achieved in the synthesis of DHCBNDO s vious decades, the development of approaches for preparing DHCBNDO green and facile way is an ongoing challenge that urgently needs to be a To supplement our initial research in the synthesis of tricyclic or organic compounds using photocatalytic reactions [26][27][28][29], we would green, facile and visible-light-mediated [2+2] cycloaddition reaction for D thesis at ambient temperature. We believe this approach not only repres and economical method for the preparation of DHCBNDOs, but also ex prospects in synthetic chemistry, such as constructing organic molecules tures.…”