Facile Metal-Free Synthesis of 3-Aryl-4-Substituted Coumarins from<i>O</i>-Hydroxy Carbonyl Compounds
作者:Kiran Taksande、D. S. Borse、Pradeep Lokhande
DOI:10.1080/00397910903222082
日期:2010.7.12
The intramolecular cyclization of the esters of salicylaldehyde, O-hydroxyacetophenones, methylsalicylate, and 2′-hydroxy chalcones by potassium hydroxide in pyridine leads to a short and convenient synthesis of 3,4-disubstituted coumarins. Twenty 3-phenyl coumarins were synthesized in 80–90% yields. No other by-product, such as 2-benzylchromone or β-diketones, was observed the reactions. The mild