A self‐assembled homochiral radical cage with paramagnetic behaviors

Condensation of an inherently C 3 -symmetric polychlorotriphenylmethyl (PTM) radical trisaldehyde with tris(2-aminoethyl)amine (TREN) yields a [4+4] tetrahedral radical cage as a racemic pair of homochiral enantiomers in 75% isolated yield. The structure was characterized by X-ray crystallography, confirming the homochirality of each cage framework. The homochirality results from intramolecular [CH‧‧‧π] and hydrogen-bonding interactions within the cage framework. The four PTM radicals in a cage undergo weak through-space coupling. Magnetic measurements demonstrated that each cage bears 3.58 spins.