Direct esterification of allylic C(sp ³ )–H via iron nanoparticle–loaded kaolin-catalyzed cross dehydrogenative coupling

Iron is the most abundant transition metal on Earth. In this study, we have demonstrated an iron nanoparticle–loaded kaolin-catalyzed cross dehydrogenative coupling (CDC) reaction via C(sp3)–H activation. We use CDC of carboxylic acids with cyclohexenes to discuss various reaction parameters such as the amount of catalyst, oxidant, reaction temperature, and time. Under optimized reaction condition, the corresponding allylic ester was obtained with good yield of (85%). Screening of substituted benzoic acids and cyclic and acyclic olefins shows broad catalytic activities. Notably, the catalyst can be easily separated from the reaction mixture via simple centrifugation and remains active over five cycles of reuse.