New Entries to 3‐Acylchromones: TM‐Catalysed Decarboxylative Cross‐Coupling of α‐Keto Acids with ortho‐Hydroxyarylenaminones, 2,3‐Unsubstituted Chromones and 3‐Iodochromones

Herein we report three new synthetic routes for the construction of a 3‐acyl‐substituted chromone scaffold by employing an acylation of ortho‐hydroxyarylenaminones, 2,3‐unsubstituted chromones and 3‐iodochromones through decarboxylative C–C cross‐coupling with α‐keto acids. This study indicates that the title transformations can be effectively catalysed by a set of silver and palladium salts. However, maximum efficiency in terms of overall yields was reported for the route starting from ortho‐hydroxyarylenaminones. The scope of this methodology was thoroughly studied. It indicated a synthesis of 26 chromone derivatives in good to excellent yields.