| Abstract
| - The syntheses of eight new star-shaped D3-symmetric arrays in which three 15-(pyrid-4-yl)porphyrinsubunits are attached to the 1, 3, and 5 positions of a benzene core through linkers consisting ofcollinear repetitive phenylethynyl units have been carried out using Pd(0)-catalyzed couplingreactions. By the same procedure, an analogous 10-(4-pyridin-yl)porphyrin hexamer in which allpositions of the benzene core are substitued has been obtained. Likewise, the preparation of suitablysized cyclic porphyrin hexamers, in which all six or at least three alternate porphyrin rings arecomplexed with Zn(II) ions, is described in detail. In solution, such cyclic porphyrin hexamers formsupramolecular assemblies with the star-shaped polyporphyrins in which the latter are held inthe interior of the macrocycle through coordination of the apical pyridine rings with the Zn(II)ions. The suggested structures are supported by 1H NMR spectroscopic and MALDI-TOF massspectrometric measurements. They agree with the high values of the binding constants of thecorresponding supramolecules, which range between K = 1.1 × 1010 and 1.4 ×109 M-1.
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