Details

Autor(en) / Beteiligte

• Sorabad, Ganesh Shivayogappa
• Yang, Ding-Yah

Titel

Lewis Acid-Catalyzed 1,4-Addition and Annulation of 4‑Hydroxy-coumarins with o‑Hydroxyphenyl Propargyl Amines: Entry to Regio-Selective Synthesis of Furano[3,2‑c]coumarins and Pyrano[3,2‑c]coumarins

Ist Teil von

• Journal of organic chemistry, 2023-04, Vol.88 (7), p.4730-4742

Ort / Verlag

United States: American Chemical Society

Erscheinungsjahr

2023

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• A facile and regioselective Lewis acid-catalyzed cascade annulation of o-hydroxyphenyl propargyl amines with 4-hydroxycoumarin to afford furano­[3,2-c]­coumarin and pyrano­[3,2-c]­coumarin derivatives is reported. The reaction presumably proceeds by the conjugate addition of 4-hydroxycoumarin to the in situ-generated alkynyl o-quinone methide and is followed by intramolecular 5-exo-dig and 6-endo-dig annulation to form furano­[3,2-c]­coumarins and pyrano­[3,2-c]­coumarins, respectively. The prepared o-hydroxyl substituted pyrano­[3,2-c]­coumarins could be readily transformed into the corresponding coumarin-derived dioxabicycles by acid-mediated cyclization.