C(sp3)–H Selective Benzylic Borylation by In Situ Reduced Ultrasmall Ni Species on CeO2

Herein, we report that highly dispersed Ni hydroxide species supported on CeO2 act as an efficient heterogeneous catalyst for the selective borylation of benzylic C­(sp3)–H bonds of alkylarenes including secondary derivatives, using pinacolborane as the borylating agent. A thorough physicochemical analysis reveals that in situ reduced ultrasmall Ni species on CeO2 during the reaction are the actual active species responsible for the borylation.