Synthesis and NaOTf mediated self-assembly of monodendritic crown ethers.

The synthesis of ten benzyl ether based self-assembling monodendrons containing benzo[15]crown-5 at their focal point is presented. These dendritic building blocks self-assemble either directly or via complexation with NaOTf in two-dimensional smectic B, smectic A, and p6mm hexagonal columnar (Phi(h)) and three-dimensional Pm3n cubic lattices. Retrostructural analysis of these lattices and of the lattices generated from the same monodendrons containing various other functional groups at their focal point by X-ray diffraction experiments provided for the first time a correlation between the molecular structure and the shape of the monodendron, the shape of the supramolecular dendrimer and the symmetry of the lattice.

Exploring and expanding the three-dimensional structural diversity of supramolecular dendrimers with the aid of libraries of alkali metals of their AB(3) minidendritic carboxylates.

The synthesis of the alkali metal salts of 3,4,5-tris(n-alkan-1-yloxy)benzoic acid [(3,4,5)nG1-CO(2)M, where n is the number of methylenic units in the alkane group for n=12, 14, 16, 18 and M=Li, Na, K, Rb, Cs] is described. The structural analysis of these AB(3) molecules by a combination of methods which includes X-ray diffraction experiments was performed. These experiments have demonstrated that (3,4,5)nG1-CO(2)M self-assemble at low temperatures into supramolecular cylinders and at high temperatures into spheres which subsequently self-organize into two-dimensional c2mm rectangular columnar, p6mm hexagonal columnar, three-dimensional Pm(-)3n and Im(-)3m cubic lattices.