Versatile Butenolide Syntheses via a Structure-Oriented C–H Activation Reaction

-butyl hydroperoxide (TBHP) as the sole oxidant. The unprecedented triazole-pyridone ligand is essential for realizing this "butenolide-oriented" C-H activation reaction. The availability of diverse aliphatic acids allows rapid access to unexplored but medicinally interesting chemical space of butenolides. Improved syntheses of a wide range of bioactive natural products and drug molecules were achieved using this reaction, including anticancer and anti-HIV compounds. As low as 1 mol % catalyst loading, ready scalability, and product purification through a simple aqueous washing represent rare practical advantages for C-H activation reactions.