Template-directed synthesis of a covalent organic capsule based on a 3 nm-sized metallocapsule.

A 4 nm-sized covalent organic capsule having 24 pyridyl groups was synthesized in extremely high yield (43% in three steps) using an octahedron-shaped metallocapsule as a template molecule. The entity was fully characterized by NMR and MALDI-TOF MS measurements. N-Methylation of the 24 pyridyl groups of the organic capsule produced a 5 nm-sized polycationic capsule, which is larger than the neutral precursory capsule because of the electrostatic repulsion between the positive charges on the pyridinium groups of the capsule.