Efficient borylation of sp3 C–O bonds by supported Au catalysts is described. Au nanoparticles supported on TiO2 showed high activity under mild conditions employing low catalyst loading conditions without the aid of any additives, such as phosphine and bases. A variety of allyl, propargyl, and benzyl substrates participated in the heterogeneously catalyzed reactions to furnish the corresponding allyl, allenyl, and benzyl boronates in high yields. Besides, Au/TiO2 was also effective for the direct borylation of allylic and benzylic alcohols. A mechanistic investigation based on a Hammett study and control experiments revealed that sp3 C–O bond borylation over supported Au catalysts proceeded through SN1′-type mechanism involving the formation of a carbocationic intermediate. The high activity, reusability, and environmental compatibility of the supported Au catalysts as well as the scalability of the reaction system enable the practical synthesis of valuable organoboron compounds.

Heterogeneous gold‐catalyzed C(sp2)−H silylation is described. A variety of heteroarenes and electron‐rich arenes participated in gold‐catalyzed silylation to afford the corresponding heteroaryl and arylsilanes in good to excellent yields. A detailed mechanistic investigation corroborated that the cooperative catalysis of ether and O2‐activated gold nanoparticles realized heterolysis of the Si−H bond to generate silyl cations, which enabled subsequent electrophilic C−Si bond formation. The high activity, reusability and environmentally‐friendly nature of the heterogeneous gold catalysts as well as the scalability of the reaction system realize the sustainable synthesis of aryl and heteroarylsilanes.

Gold-catalyzed thioetherification of C(sp3)–O bonds is described. The reaction of allyl phosphates and thiosilanes in the presence of gold nanoparticles supported on ZrO2 proceeded efficiently under mild reaction conditions to...

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