An Aromatic Oligomer Micelle: Large Enthalpic Stabilization and Selective Oligothiophene Uptake.

An aromatic oligomer micelle, featuring both  high stability and  high uptake ability , was quantitatively formed in water from amphiphilic oligomers, composed of three bent polyaromatic amphiphiles connected alternately by two hydrophilic chains. The well-defined micelle, with a diameter of ~2 nm, remains intact even under highly diluted conditions (~3 μM) and at elevated temperature (>130 oC), due to the polyaromatic chelate effect. The thermodynamic studies reveal that large enthalpic gain ( Δ H  = -110 kJ mol -1 ) is the key for the micelle formation. The oligomer micelle selectively encapsulates unsubstituted oligothiophenes (≥4-mer) to a high degree and the resultant, aqueous host-guest complexes display unusual emission derived from the multiply stacked oligomers. Furthermore, facile uptake and release of unsubstituted polythiophenes can be achieved using the oligomer micelle.