Aromatic compounds as synthons for 1,3-dicarbonyl derivatives

This tutorial review covers the applications of aromatic compounds such as anisole derivatives as synthetic equivalents (synthons) for 1,3-dicarbonyl compounds. The aromatic nucleus is first converted under reductive Birch conditions to the corresponding 1,4-cyclohexadiene compound which is then subjected to ozonolysis. The reductive work-up of the ozonides generates the 1,3-dicarbonyl compounds. The usefulness of this reaction sequence is demonstrated in several syntheses of complex molecules. A new access to 1,3-dicarbonyl compounds by an alternative approach utilising a cobalt-catalysed Diels-Alder reaction or a 1,4-hydrovinylation reaction to generate the needed 1,4-diene derivatives is briefly discussed.