Self-Assembly of Catalytically Active Supramolecular Coordination Compounds within Metal–Organic Frameworks

Supramolecular
coordination compounds (SCCs) represent the power
of coordination chemistry methodologies to self-assemble discrete
architectures with targeted properties. SCCs are generally synthesized
in solution, with isolated fully coordinated metal atoms as structural
nodes, thus severely limited as metal-based catalysts. Metal–organic
frameworks (MOFs) show unique features to act as chemical nanoreactors
for the in situ synthesis and stabilization of otherwise
not accessible functional species. Here, we present the self-assembly
of PdII SCCs within the confined space of a pre-formed
MOF (SCCs@MOF) and its post-assembly metalation to give a PdII–AuIII supramolecular assembly, crystallography
underpinned. These SCCs@MOFs catalyze the coupling of boronic acids
and/or alkynes, representative multi-site metal-catalyzed reactions
in which traditional SCCs tend to decompose, and retain their structural
integrity as a consequence of the synergetic hybridization between
SCCs and MOFs. These results open new avenues in both the synthesis
of novel SCCs and their use in heterogeneous metal-based supramolecular
catalysis.