A Polyaromatic Gemini Amphiphile That Assembles into a Well-Defined Aromatic Micelle with Higher Stability and Host Functions.
Tomoya NishiokaKiyonori KurodaMunetaka AkitaMichito YoshizawaPublished in: Angewandte Chemie (International ed. in English) (2019)
A gemini-type amphiphilic molecule, constituted of two V-shaped polyaromatic amphiphiles linked by a linear acetylene spacer, was synthesized. The gemini amphiphile assembles into a well-defined aromatic micelle (ca. 2 nm in core diameter), providing higher stability in water even at low concentration (0.09 mm) and high temperature (>130 °C). Unlike common gemini amphiphiles with aliphatic chains, the present amphiphile and its micellar assembly emit green and orange fluorescence (ΦF =33 and 9 %), respectively. Despite strong and multiple π-stacks of the polyaromatic panels of the amphiphiles, the water-soluble gemini aromatic micelle incorporates medium-size to large hydrophobic compounds into the frameworks. Interestingly, the guest binding capability toward large planar molecules was enhanced by more than two times through the pre-encapsulation of spherical molecules in the cavity.