Metal-Coordination-Induced Fusion Creates Hollow Crystalline Molecular Superstructures

In this work, we
report the formation of superstructures assembled
from organic tubular crystals mediated by metal-coordination chemistry.
This template-free process involves the crystallization of molecules
into crystals having a rectangular and uniform morphology, which then
go on to fuse together into multibranched superstructures. The initially
hollow and organic crystals are obtained under solvothermal conditions
in the presence of a copper salt, whereas the superstructures are
subsequently formed by aging the reaction mixture at room temperature.
The mild thermodynamic conditions and the favorable kinetics of this
unique self-assembly process allowed us to ex-situ monitor the superstructure formation by electron microscopy, highlighting
a pivotal and unusual role for copper ions in their formation and
stabilization.