A nanoscale supramolecular hexagon, 1, and its supramolecular isomeric chain structure, 2, have been prepared from self-assembly of 5-NO2-bdc and Cu(II) cations. The hexagon is neutral and soluble and has outer and inner diameters of 3.1 and 0.8 nm, respectively.

The self-assembly of [Cu2(dicarboxylate)2]4 nanoscale secondary building units (nSBUs) into coordination polymers can occur in such a way that a range of calix-like atropisomers can exist. Eight compounds have been prepared and crystallographically characterized via reaction between Cu(NO3)2 and angular dicarboxylate ligands:  {[Cu2(bdc)2(py)2]4•guest} n (1a), {[Cu2(bdc)2(py)2]4•4nitrobenzene•2EtOH} n (1b), {[Cu2(bdc)2(4-pic)2]4•4o-dichlorobenzene} n (2), {[Cu2(5-OEt-bdc)2(py)2]4•8H2O} n (3), {[Cu2(5-OPr-bdc)2(py)2]4•guest } n (4), {[Cu2(pdc)2(py)2]4•4MeOH} n (5), {[Cu2(pdc)2(4-pic)2]4•4H2O} n (6), and {[Cu2(tdc)2(MeOH)2]4•4naphthalene•8MeOH} n (7). The following atropisomers, all of which have also been observed in calixarenes, were observed:  (a) cone (1a, 3, and 4); (b) partial cone (1b); (c) 1,2-alternate (2 and 5−7); and (d) 1,3-alternate (1a, 3, and 4). The similarities and differences between the crystal structures of 1−7 are detailed herein.