Regioselective Halogenation of 2H-Chromenones Promoted by Oxone and NaX: A Facile Approach for the Preparation of Halochromenones and 2H-Chromenone Natural Products

摘要

A systematic study has been conducted for the regioselective halogenation of 2H-chromenones to prepare 3-halo-2H-chromenones,4-substituted 3-halo-2H-chromenones and 3-(2-haloacetyl)-2H-chromenones.Commercially available NaCl/NaBr has been used as halogen source and oxone as an oxidant to produce the compounds.Further,the method has been successfully applied for the preparation of pharmaceutically important halogenated 2H-chromenone natural products.The present approach is simple,economically viable and provided the target compounds with good yields.