Tetra-2-pyridinylpyrazine (TPP) or 2,3,5,6-tetra-2-pyridinylpyrazine (tppz) is a poly-N-donor ligand. Application Tetra-2-pyridinylpyrazine (tppz, tpyprz) may be used as a ligand in the synthesis of the following metal complexes: [{CuCl}2(μ-tppz)][PF6]2 (PF6=hexafluorophosphate) [(Cp*2Ln)2(μ-tppz.)](BPh4) (Cp*=pentamethylcyclopentadienyl; Ln=Gd, Tb, Dy; BPh4=tetraphenyl borate) [Fe(tpyprz)2]2[Mo8O26]·3.7H2O (Mo8O26=octamolybdate)