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Updated: Sep 27, 2025

Efficient Synthesis of Polyfunctionalized Benzenes in Water via Persulfate-promoted Benzannulation of α,β-Unsaturated Compounds and Alkynes
Published on: December 16, 2019
Regiocontrolled Annulation of Benzocyclobutenols with Alkynes
Qin-Qiong Zeng1, Yong-Qi Wang1, Lang Cheng1
1College of Chemistry and Materials Science, Sichuan Normal University, Chengdu, Sichuan 610066, P. R. China.
Abstract:
A tandem reaction that involves an unprecedented Rh-catalyzed intramolecular annulation of benzocyclobutenols with alkynes and subsequent ZnCl2-promoted dehydration was developed, offering an efficient approach to 2H-furan-, pyran-, and oxepine-fused naphthalenes. Furthermore, the 2H-furan motif may undergo a ring-opening reaction through Fe-catalyzed reductive C-O bond cleavage. As a consequence, the formal intermolecular annulation of 2-hydroxybenzocyclobutenols with alkynes was realized with complete regioselectivity through a two-step protocol.
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