Entrapment of Metal Clusters in Metal–Organic Framework Channels by Extended Hooks Anchored at Open Metal Sites

Reported
here are the new concept of utilizing open metal sites
(OMSs) for architectural pore design and its practical implementation.
Specifically, it is shown here that OMSs can be used to run extended
hooks (isonicotinates in this work) from the framework walls to the
channel centers to effect the capture of single metal ions or clusters,
with the concurrent partitioning of the large channel spaces into
multiple domains, alteration of the host–guest charge relationship
and associated guest-exchange properties, and transfer of OMSs from
the walls to the channel centers. The concept of the extended hook,
demonstrated here in the multicomponent dual-metal and dual-ligand
system, should be generally applicable to a range of framework types.