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

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 2-aryl-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.

Automated summary

A 1,8-diazabicyclo[5.4.0]-undec-7-ene-promoted cascade double-annulation of ortho-alkynyl quinone methide is developed for constructing of 2-aryl-4-hydroxybenzo-[c]-chromen-6-ones. This method offers operational simplicity and good functional group compatibility.