Herein, a novel metal–organic
framework (MOF) with a pillared-layer
structure was rationally synthesized to initiate intermolecular atom-transfer
radical addition (ATRA) via photoinduced electron transfer activation
of haloalkanes. The MOF synthesized via the controllable pillared-layer
method is of excellent visible-light absorption and high chemical
stability. Photocatalytic experiments show the atom transfer of various
alkyl halides (R–X, X = Cl/Br/I) onto diverse olefins was successfully
achieved to produce functional ATRA products. The mechanism and experimental
investigations reveal the prepared MOF serves as an efficient photocatalyst
with strong reduction potential to activate haloalkane substrates
via photoinduced electron transfer, generating a highly reactive alkyl
radical to trigger the ATRA reaction. Key events in the ATRA reaction,
including alkyl radical photogeneration as well as halide transfer,
have been further regulated to achieve preferable photocatalytic performance
with higher yields, shorter reaction time, and desirable cycling capability.
It is notable that the work is the first report on photoinduced electron
transfer activation of halides by a MOF photocatalyst for the ATRA
reaction, providing a new blueprint for MOFs to develop photoinduced
radical reactions.