Cu(II) coordination polymer containing N2S2 type tetradentate ligand, N,N′-bis(β-methylmercaptoethyl)piperazine (mmepa)

[Cu(mmepa)(MeCN)](ClO4)2 (1) and [Cu2(mmepa)(1,1-N3)2(N3)2]n (2) containing the flexible N2S2 type tetradentate ligand, N,N′-bis(β-methylmercaptoethyl)piperazine (mmepa), have been synthesized and their molecular structures have been determined by single crystal X-ray analyses. The square pyramidal environment of Cu(II) centre of 1 is consisted with two nitrogen atom and two sulfur atoms of the mmepa ligand in square plane and another nitrogen atom of MeCN in axial position. Meanwhile, [Cu2(mmepa)(1,1-N3)2 (N3)2]n (2) formed 1D infinite structure, in which azido ligand bridge Cu(II) centres as an end-on mode.