Cascade Annulation Strategy for Expeditious Assembly of Hydroxybenzo[c]chromen-6-ones and Their Photophysical Property Studies

Abstract

A 1,8-diazabicyclo[5.4.0]undec-7-ene-promoted cascade double-annulation of ortho-alkynyl quinone methide (in situ generated from modular propargylamine) for constructing of 2aryl-4-hydroxybenzo[c]chromen-6-ones is developed. This synthetic strategy offers remarkable operational simplicity as it allows the use of benchtop-grade solvents without the need for predrying measures and inert atmosphere protection. Additionally, it demonstrates good functional group compatibility. The photophysical properties of these compounds were also examined, revealing bright fluorescence with high quantum yields.

BF3·OEt2 Catalyzed Cascade [4 + 2] Benzannulation of Vinyloxiranes with Coumarins to Construct Benzocoumarin Derivatives

“…Given the remarkable bioactivities exhibited by these scaffolds, extensive studies have been conducted on related synthetic methodologies. Currently, the synthesis of benzocoumarin primarily relies on approaches to construct pyranone portion, with limited reports utilizing benzannulation reactions to deliver the aryl motif. Therefore, it is imperative to develop rapid and efficient strategies for constructing benzocoumarin through benzannulation reactions.…”