Stepwise Construction of Extra-Large Heterometallic Calixarene-Based Cages

Utilizing
presynthesized large Na2Ni12Ln2 clusters
(Ln = Dy and Tb) supported by calixarene as molecular building blocks
(MBBs), we have obtained a series of cationic trigonal prismatic heterometallic
organic nanocages (HMONCs) with tunable sizes through a stepwise method.
Specially, in each structure of the HMONCs, three linear dicarboxylate
linkers substitute the peripheral coordinated acetate ligands of two
Na2Ni12Ln2 clusters to form an unprecedented
Na4Ni24Ln4 HMONC through a M2L3 condensation. Moreover, magnetic study reveals
that the Na2Ni12Dy2 core retains
its slow magnetic relaxation behavior. Gas sorption behaviors of these
HMONCs were also studied. To the best of our knowledge, these HMONCs
built from large heterotrimetallic Na2Ni12Ln2 MBBs, which are based on smaller Ni4-calix ones,
have not been reported in any other cages to date. In addition, this
research also provides a new strategy for the design and construction
of HMONCs with predictable structures and functional properties.