Structure analysis & property of tetrazole-based transition metal complexes

Abstract

The inorganic coordination polymers including 5-(2-hydroxyphenyl)-1H-tetrazole(=tzOH) as the main-ligand role and 2,2’-bipyrimidine(=bpym) as the sub-ligand role were induced with 4-period transition metals. At the first, in case of Ni(II), monomeric compound of zero-dimensional structure, $Ni(bpym)_2(TzO)$, (1), including one tzOH ligand and two bpym ligands used as the terminal ligands could be obtained. Second, in case of Cu(II) and Zn(II), Cu(II) compound $[Cu(bpym)(TzO)]_n$, (2), which has 1-dimensional structure of zigzag type and Zn(II) compound, $[Zn(bpym)(TzO)]_n$, (3), which has 2-dimensional structure could be obtained. In these compounds, tzOH was used by bridging ligands connecting between metal and metal and bpym was used by a terminal ligand blocking two coordination sites of metal. In two cases, the fundamental unit composed of one tzOH and one bpym ligand per one metal is the same, however, in case of Zn(II) compound, new dimer unit was formed as the two unit combined with each other differently about Cu(II) compound. Lastly, in case of Fe(III), the fundamental unit that is composed of three tzOH ligands and Fe(III) and has distorted octahedral structure and $C_3$ symmetry could be obtained. This unit has two sides; oxygen side and nitrogen side. Using these sides, the unit was connected with potassiums. As a consequence, it could be found structurally that Fe(III) compound grew along three axis and that has 3-dimensional structure. In addition, it could be also found that the distance, 3.540Å, between Fe(III) and potassium is sufficiently close as 3.540Å compared with some values that had already been reported. Therefore, it could be referred that dimensionality of complexes could be controlled by kinds of transition metals using common ligands, tzOH and bpym. In case of Ti(IV), the compounds of three types were synthesized and characterized structurally; $[(η^5-C_5H_5)TiCl_2(TzO)](THF)_{1.5}$ , (1), $[TiCl_3(TzO)(THF)](THF)$, (2), $[TiCl_2...