Bringing a Mechanistic Lens to the Development of New Transfer Hydroarylation Isodesmic Reactions for the Synthesis of Amides, Thioamides, Amidines, Alkenes and Ketones from Carboxylic Acids via Extrusion and Insertion Elementary Steps

The wide availability, ease of handling and structural and functional diversity make carboxylic acids prized building blocks in organic synthesis. The past two decades has seen an explosion of interest in the development of new modes of reactivity of carboxylic acids and their derivatives. Of these, metal-mediated decarboxylation reactions are attractive as they produce organometallic intermediates that can subsequently be used in C-X (where X=C, N, S etc) bond coupling reactions. Here the results of mechanistic studies integrating both gas- and condensed-phase work are described for development of new extrusion-insertion (ExIn) classes of reactions for the synthesis of amides, thioamides, amidines, alkenes and ketones from arylcarboxylic acids and suitable (hetero)cumulenes.