Gil-Jae Park's research while affiliated with Pohang University of Science and Technology and other places

Syntheses of molecular necklaces and open framework materials using coordiantion bonds are described. In the synthesis of molecular necklaces, the barrel-shape molecule cucurbituril is used as a molecular “bead” and metal ions or metal complexes are used as “glue” or “angle connectors”. Two different approaches were taken. In one approach, linear pseudorotaxanes react with Pt(en)(NO3)2 (en = ethylenediamine) to produce [4]MNs and [5]MNs. In the other approach, a′ 2 + 2′ approach, preorganized, L-shaped pseudorotaxanes containing two molecular “beads” react with a metal ion (or a metal complex with cis vacant coordination sites) to form [5]MNs. Rubidium and cucurbituril form a one-dimensional coordination polymer in the solid state, in which cucurbituril molecules stack atop one another through coordination of their carbonyl groups to the rubidium ions in between. The coordination polymer chains are arranged in such a way as to produce a honeycomb structure with large linear hexagonal channels parallel to the polymer chains.

Eine Perle der supramolekularen Art: Eine rechteckige molekulare „Perlenkette” mit vier molekularen Perlen entsteht durch Umsetzung zweier L-förmiger, je zwei molekulare Perlen (Cucurbituril, symbolisiert durch die Fässer) enthaltender Pseudorotaxane mit Cu2 +-Ionen [Gl. (1)].

Like with a string of pearls, four molecular “beads” are threaded on a molecular rectangle to form a molecular necklace. This rectangular species is synthesized from two L-shaped, preorganized pseudorotaxanes with two molecular beads each (cucurbituril, schematically symbolized by the barrels), held together by Cu2+ ions [Eq. (1)].