Science, Vol.361, No.6408, 1242-1245, 2018
Self-assembly of lattices with high structural complexity from a geometrically simple molecule
Here we report an anomalous porous molecular crystal built of C-H center dot center dot center dot N-bonded double-layered roof-floor components and wall components of a segregatively interdigitated architecture. This complicated porous structure consists of only one type of fully aromatic multijoint molecule carrying three identical dipyridylphenyl wedges. Despite its high symmetry, this molecule accomplishes difficult tasks by using two of its three wedges for roof-floor formation and using its other wedge for wall formation. Although a C-H center dot center dot center dot N bond is extremely labile, the porous crystal maintains its porosity until thermal breakdown of the C-H center dot center dot center dot N bonds at 202 degrees C occurs, affording a nonporous polymorph. Though this nonporous crystal survives even at 325 degrees C, it can retrieve the parent porosity under acetonitrile vapor. These findings show how one can translate simplicity into ultrahigh complexity.