Chalkones: reactivity of some aryl alkoxystyryl ketones and their dihalides

Abstract

An investigation of the reaction of some aryl alkoxystyryl ketones and their dihalides has shown that the alkoxystyryl nucleus, if free from halogen, is readily halogenated. Potassium iodide in acetone removes the side-chin halogen from the chalkone dihalides, and this reaction can be used to determine the position of the halogen in the nucleus. The side-chin halogen atom adjacent to the numceus containing the alkoxy-group is readily replaced by alkoxyl on treatment with alcohols. The dihalides with alcoholic potassium cyanide give b-aroyl-a-phenylpropionitriles. With bases the chalkone dohalides give a-halogenostyryl derivatives and b-alkoxystyryl ketones. The production of isooxazoles from the dihalides by the action of hydroxyl-amine and the condensation of the chalkones with acetoacetic ester have also been examined. The production of benzylidenecoumaranones in place of flavones from o-hydroxy- or o-acetoxy-phenyl alkoxy-phenyl alkoxystyryl ketone dibromides probably depends on whether or no a b-alkoxy-compund is intermediately formed.