Propanediurea-Based Molecular Clips Bind Halide Anions: An Insight into the Mechanism of Cucurbituril Formation.
The synthesis and supramolecular properties of the first methylene-bridged propanediurea-based dimers are described. These dimers, bearing an aromatic sidewall, have the shape of molecular clips. Unlike glycoluril-based dimers, these clips neither dimerize nor accept any organic guests, due to their small cavities. Both propanediurea- and glycoluril-based dimers bind halide anions on the convex side of the molecules, even in highly polar organic solvents. This observation brings new insights into the mechanism of cucurbituril formation.
Department of Chemistry and ‡RECETOX, Masaryk University , Kamenice 5, 62500 Brno, Czech Republic.
Tomas
T
Lizal
Department of Chemistry and ‡RECETOX, Masaryk University , Kamenice 5, 62500 Brno, Czech Republic.
Lukas
L
Ustrnul
Department of Chemistry and ‡RECETOX, Masaryk University , Kamenice 5, 62500 Brno, Czech Republic.
Marek
M
Necas
Department of Chemistry and ‡RECETOX, Masaryk University , Kamenice 5, 62500 Brno, Czech Republic.
Vladimir
V
Sindelar