Synthesis of 3-halochromones with simple KX halogen sources enabled by in situ halide oxidation†
Abstract
On the basis of a designated in situ oxidation tactic, the synthesis of 3-halochromones has been realized for the first time by using simple KX (X = Br, I) salts as halogen sources. Instead of the free radical process, the control experiments indicate that the reported reactions proceed through a halogenium intermediate. Compared to the known synthetic methods relying on molecular halogen, haloid acid or N-halosuccinimide as the halogen source, the present method is attractive due to its higher atom economy and being more friendly to the operator, thus providing a practical complimentary approach to the preparation of useful halochromone compounds.