Decarboxylative Aminocatalytic Cascade for the Synthesis of Dihydroxanthones

A novel decarboxylative aminocatalytic strategy for the synthesis of 4,4a-dihydroxanthones is described. It was realized by employing dienamine activation and utilizes readily available beta, beta-disubstituted enals and chromone-3-carboxylic acids as starting materials. A decarboxylation reaction is the key step of the cascade making the aminocatalyst turnover possible.