New classes of organic Chelate-Free coordination Polymers: An End-On Azido-Bridged Cu(II) 1-D chain composed of {Cu6(N3)12} repeating units

Abstract

The use of Me3SiN3 in CuII chemistry, under basic conditions, in the absence of any ancillary organic chelate, has led to an unusual 1-D coordination polymer (1) composed of {Cu6(N3)12} repeating units. The metal ions in 1 are exclusively bridged by μ3-1,1,1 and μ-1,1 end-on N3– groups. Peripheral ligation about the {Cu6(N3)12} core is provided by eight MeCN solvate molecules. IR and UV/Vis spectroscopic data fully support the presence of end-on azides and d-d transitions of the metal ions, respectively. Magnetic susceptibility measurements revealed a continuous drop of the χΜΤ product and an overall antiferromagnetic response, which results in a local S = 0 spin for the {Cu6(N3)12} repeating units of 1. The combined results demonstrate the flexibility of this synthetic approach to purely inorganic-bridged coordination complexes (clusters and polymers) and its ability to yield new molecule-based materials with several potential applications, i.e., in molecular magnetism, catalysis, high energy materials and photochemistry.