Plasmonic Silver‐Nanoparticle‐Catalysed Hydrogen Abstraction from the C(sp3)−H Bond of the Benzylic Cαatom for Cleavage of Alkyl Aryl Ether Bonds

Abstract

AbstractSelective activation of the C(sp3)−H bond is an important process in organic synthesis, where efficiently activating a specific C(sp3)−H bond without causing side reactions remains one of chemistry's great challenges. Here we report that illuminated plasmonic silver metal nanoparticles (NPs) can abstract hydrogen from the C(sp3)−H bond of the Cαatom of an alkyl aryl etherβ‐O‐4 linkage. The intense electromagnetic near‐field generated at the illuminated plasmonic NPs promotes chemisorption of theβ‐O‐4 compound and the transfer of photo‐generated hot electrons from the NPs to the adsorbed molecules leads to hydrogen abstraction and direct cleavage of the unreactive ether Cβ−O bond under moderate reaction conditions (≈90 °C). The plasmon‐driven process has certain exceptional features: enabling hydrogen abstraction from a specific C(sp3)−H bond, along with precise scission of the targeted C−O bond to form aromatic compounds containing unsaturated, substituted groups in excellent yields.