Herein, a metal- and photosensitizer-free protocol has been developed for decarboxylative C–H (amino)alkylation of heteroarenes using carboxylic acids as the (amino)alkylating reagents. This reaction is performed in a sustainable solvent (dimethyl carbonate, DMC). Various carboxylic acids (tertiary, secondary, and primary carbon) are well tolerated, providing the target products in acceptable yields. More importantly, such an approach can also efficiently convert a wide range of amino acids and carboxyl-containing drugs into desired products. This protocol provides a green and efficient approach for the rapid conversion of abundant feedstock materials into medically relevant “drug-like” moieties.