Self-assembly of chiral coordination polymers and macrocycles: A metal template effect on the polymer-macrocycle equilibrium

The self-assembly of racemic and enantiopure binaphthyl-bis(amidopyridyl) ligands 1,1'-C20H12{NHC(=O)-4-C5H4N}(2), 1, and 1,1'-C20H12{NHC(=O)-3-C5H4N}(2), 2, with mercury(II) halides (HgX2; X = Cl, Br, I) to form extended metal-containing arrays is described. It is shown that the self-assembly can lead to homochiral or heterochiral polymers or macrocycles, through self-recognition or self-discrimination of the ligand units, and the primary materials can further self-assemble through hydrogen bonding between amide substituents. In addition, the formation of macrocycles or polymers can be influenced by the presence or absence of excess mercury(II) halide, through a template effect, and mercury(II) halide inclusion complexes may be formed. In one case, an unusual polymeric compound was obtained, with 1 guest HgX2 molecule for every 12 mercury halide units in the polymer.