Cascade oxa-Michael–Henry reactions of salicylaldehyde derivatives with β-nitrostyrenes
catalyzed by potassium carbonate via solvent-free ball milling are demonstrated. The
corresponding 3-nitro-2H-chromene products were obtained in moderate to excellent yields. This method offers
significant advantages, particularly in terms of high yields, short reaction times
and mild conditions.
Key words
solvent-free - ball milling - cascade - oxa-Michael–Henry reaction - 3-nitro-2
H-chromenes