Size-selective recognition by a tubular assembly of phenylene-pyrimidinylene alternated macrocycle through hydrogen-bonding interactions.

Study of artificial tubular assemblies as a useful host scaffold for size-selective recognition and release of guest molecules is an important subject in host-guest chemistry. We describe well-defined self-assembled nanotubes (NT6mer) formed from π-conjugated m-phenylene-pyrimidinylene alternated macrocycle 16mer that exhibit size-selective recognition toward a specific aromatic acid. In a series of guest molecules, a size-matched trimesic acid (G3) gives inclusion complexes (NT6mer⊃G3) in dichloromethane resulting in an enhanced and red-shifted fluorescence.