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Sulfur/DABCO Promoted Reductive Coupling/Annulation Cascade Reaction between o-Hydroxy/Amino Nitrobenzenes and Benzaldehydes

Minh-Huy Dinh Dang, Linh Ho Thuy Nguyen, Phuong Hoang Tran*

*Department of Organic Chemistry, Faculty of Chemistry, University of Science, Vietnam National University, Ho Chi Minh City (VNU-HCM) 721337, Vietnam, Email:

M.-H. D. Dang, L. H. T. Nguyen, P. H. Tran, Synthesis, 2020, 52, 1687-1694.

DOI: 10.1055/s-0039-1690823 (free Supporting Information)

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The combination of sulfur and DABCO efficiently promotes a reductive coupling/annulation of o-nitrophenols or o-nitroanilines with benzaldehydes. This method represents a simple, straightforward, and green approach to the construction of benzoxazoles and benzimidazoles.

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Key Words

benzoxazoles, sulfur, reductive coupling, annulation, green chemistry

ID: J66-Y2020