Elemental Sulfur/DMSO-Promoted Multicomponent One-pot Synthesis of Malonic Acid Derivatives from Maleic Anhydride and Amines

Malonic acid derivatives could be conveniently prepared with high degree of functional flexibility via redox condensation reactions between anhydride maleic, amines, elemental sulfur and DMSO as oxidant. This multicomponent decarboxylative transformation consists in a cascade of ring opening, decarboxylative oxidative thioamidation at temperature as low as 50 degrees C.