Coordinating nature of ML double-stranded macrocycles: co-ligand competition of perchlorate, water, and acetonitrile depending on metal() ions

Self-assembly of M(ClO 4 ) 2 (M( ii ) = Mn( ii ), Co( ii ), Ni( ii ), Cu( ii ), and Zn( ii )) with dicyclopentyldi(pyridine-3-yl)silane (L) as a donor in a mixture of acetonitrile and toluene produces crystals consisting of M 6 L 12 double-stranded macrocycles. The geometry around the M( ii ) cations is a typical octahedral arrangement, but the metallamacrocycles' outer axial coordination environment is sensitive to the M( ii ) cations. The conformation of the unique metallamacrocycles is informatively dependent on the nature of the coordination around the M( ii ) cations via subtle co-ligand competition among perchlorate anions, water, and acetonitrile. Both the coordinated acetonitriles and the solvate molecules of the crystals are removed at 170 °C, thereby transforming the crystals into new crystals that return to their original form in the mixture of toluene and acetonitrile. Catalytic oxidation of 3,5-di- tert -butylcatechol using [Cu 6 (ClO 4 ) 8 (CH 3 CN) 4 L 12 ]4ClO 4 ·5C 7 H 8 is much faster than those using the transformed product, [Cu(ClO 4 ) 2 L 2 ], and a simple mixture of Cu(ClO 4 ) 2 + L. The outer coordinating nature of a unique M 6 L 12 (M( ii ) = Mn( ii ), Co( ii ), Ni( ii ), Cu( ii ), and Zn( ii )) metallamacrocyclic system is informatively dependent on M( ii ) cations via subtle co-ligand competition among ClO 4 − anions, H 2 O, and CH 3 CN.