Synthesis of oligopyrrolic cluster bearing thiophene spacer as potential anion receptors

The oligopyrrolic clusters and tripyrrylmethane have been synthesized and characterized by the utilization of 2-formylpyrroles and their derivatives as building blocks. Condensation of dialdehydes 9 with pyrrole in the presence of BF3(Et2O) resulted in the formation of tripyrrlymethane 10, while similar condensation performed in trifluoroacetic acid afforded oligopyrrolic cluster 11 on the other hand. The nature of substituents at meso-positions resulted in the formation of completely different products.