Synthesis of α‐Quaternary Carboxylic Acids through Cu‐Catalyzed Hydrocarboxylation of Allenes with Diisobutylaluminum Hydride and Carbon Dioxide

Abstract

AbstractA regioselective method for synthesizing β,γ‐unsaturated α‐quaternary carboxylic acids through the copper‐catalyzed hydrocarboxylation of allenes with CO2 is described. Allenes undergo hydroalumination with diisobutylaluminum hydride, followed by carboxylation of the resulting allylaluminum intermediate. The presence of an N‐heterocyclic carbene ligand is essential for enhancing the reactivity of the reaction. The good functional group compatibility of the reaction allows the synthesis of a wide range of functionalized α‐quaternary carboxylic acids with high regio‐ and stereoselectivities for synthetic and medicinal applications.