π-Conjugated [2]Catenanes Based on Oligothiophenes and Phenanthrolines: Efficient Synthesis and Electronic Properties

Novel π-conjugated topologies based on oligothiophenes and phenanthroline have been assembled by combining their outstanding electronic and structural benefits with the specific properties of the topological structure. Macrocycles and catenanes are prepared by using an optimized protocol of transition metal-templated macrocyclization followed by efficient Pd-catalyzed cross-coupling reaction steps. By using this method, [2]catenanes comprising two interlocked π-conjugated macrocycles with different ring sizes have been synthesized. The structures of the [2]catenanes and corresponding macrocycles are confirmed by detailed (1) H NMR spectroscopy and high resolution mass spectrometry. Single crystal X-ray structural analysis of the quaterthiophene-diyne macrocycle affords important insight into the packing features and intermolecular interaction of the new systems. The fully conjugated interlocked [2]catenanes are fully characterized by spectroscopic and electrochemical measurements.