Selective Removal of Aminoquinoline Auxiliary by IBX Oxidation

8-Aminoquinoline (AQ) is a widely used bidentate auxiliary in metal-catalyzed directed C-H functionalization reactions. Herein, we report an efficient and chemoselective method to convert various N-quinoly carboxamides to primary amides with the treatment of stoichiometric amount of 2-iodoxybenzoic acid (IBX) oxidant or the combination of catalytic amount of 2-iodobenzoic acid (2-IBA) and Oxone co-oxidant in mixed solvents of H2O and HFIP. Its unique compatibility with the Phth-protected α-amino acid (αAA) substrates enhances the overall synthetic utility of AQ-directed palladium-catalyzed C-H functionalization strategy for synthesis of complex αAAs.