Metal-Free sp3 C-H Functionalization: PABS/I2-Promoted Synthesis of Polysubstituted Oxazole Derivatives from Arylethanones and 2-Amino-2-alkyl/arylacetic Acid

A nonmetal-catalyzed process for the synthesis of polysubstituted oxazoles from inexpensive and readily available -amino acids and methyl ketones is established. This reaction is proposed to achieve oxidative cleavage of C(sp(3))-H bonds, followed by decarboxylation and annulation. The mild reaction conditions employed in both cases enable the tolerance of a wide range of functional groups as well as high reaction efficiency.