2-Alkyl-5-hydroxychromones (2-alkyl-5-hydroxy-4-oxo-4H-1-benzopyran) and 3-alkoyl-2-alkyl-5-hydroxychromones (3-alkoyl-2-alkyl-5-hydroxy-4-oxo-4H-1-benzopyran) were prepared in one-step and one pot reaction by condensation of 2′,6′-dihydroxyacetophenone with an alkoyl chloride in the presence of K2CO3.
Unified Approach to (Thio)chromenones via One-Pot Friedel–Crafts Acylation/Cyclization: Distinctive Mechanistic Pathways of β-Chlorovinyl Ketones
作者:Hun Young Kim、Eunsun Song、Kyungsoo Oh
DOI:10.1021/acs.orglett.6b03348
日期:2017.1.20
method to chromenones and thiochromenones has been developed using a one-pot Friedel–Craftsacylation of alkynes with suitably substituted benzoyl chlorides. This unified approach to (thio)chromenones is readily applicable to aryl- and alkylalkynes where the stereochemically well-defined β-chlorovinyl ketone intermediates undergo distinctively different cyclization pathways. The ready availability