Formation of Diquinoline Molecular Bricks and Their Assembly into Lattice Inclusion Compounds

The dibromodiquinoline derivative 2 yields crystalline lattice inclusion compounds with a wide range of guest molecules. The solvent-free crystal structure is also formed. In all these, pairs of dibromodiquinoline molecules form centrosymmetric brick-like dimers by means of three different aromatic edge−face (EF) interactions. The resultant (EF)6 building blocks, which are virtually identical across the series of 13 crystal structures described, act as tectons that pack into layers. Guest molecules occupy interlayer spaces near the corners of the tectons, with the host−guest attractions acting as molecular mortar and allowing variation of the inclusion structures dependent on guest size, shape, and functionality. The apohost crystal structure demonstrates that guest-free packing of these molecular bricks (analogous to the dry stone construction method) is also favorable. The molecular substitution of a dibromodiquinoline unit required to ensure dimeric (EF)6 tecton formation is explained.