Flexible and Redox-Active Coordination Polymer: Control of the Network Structure by Pendant Arms of a Macrocyclic Complex

The coordination polymer {[Ni(C20H32N8)](2)[TCM]}center dot 5DMF center dot 8H(2)O (1) has been assembled from a Ni-II macrocyclic complex that contains two pyridyl pendant arms, [Ni(C20H32N8)(ClO4)(2), and sodium tetrakis[4-(carboxyphenyl)oxamethyl]methane (Na4TCM) in DMF/water. The X-ray structure of 1 reveals that the pyridyl pendant arms in the macrocyclic complex play a crucial role in determining the network structure through the pi-pi interactions. Compound 1 forms doubly catenated rhombic grids that generate 11) channels. It exhibits flexible behavior upon desorption/resorption and exchange of organic guest molecules as well as temperature change. Solid 1 is redox active due to the incorporated Ni-II macrocyclic species, and reacts with Pd(NO3)(2) dissolved in acetonitrile at room temperature to produce small Pd nanoparticles[(2.9 +/- 0.4) nm in diameter] in the channels in the absence of extra reducing or capping agents.