Copper‐Catalyzed Oxidative Decarboxylative Olefination of Sp ³ C─H Bonds Using Cinnamic Acid

ABSTRACT A copper(II)‐catalyzed strategy has been developed for the decarboxylative coupling of cinnamic acids with toluene, enabling the formation of new C(sp 2 )—C(sp 3 ) bonds through C(sp 3 )—H functionalization in the presence of di‐tert‐butyl peroxide (DTBP) as an oxidant. The Cu(II)‐DMAP/DTBP catalytic system promotes this transformation via a radical addition–elimination mechanism. This efficient and cost‐effective method provides rapid and selective access to a wide range of olefins in moderate to high yields under mild, air‐stable conditions.