Syntheses and structure of 2,11-dithia[3.3](2,6)pyrazinophane and its coordination complexes of Cu(I) and Co(II)

The cyclophane ligand, 2,11-dithia[3.3](2,6)pyrazinophane (L), was synthesized by a simpler method and characterized by 1H NMR, which was used to synthesize coordination complexes by reactions with Cu+ (I) and Co2+ (II) cations. Single-crystal X-ray analysis revealed that the conformation of the ligand L is syn(boat-chair), while in I and II it adopts syn(boat-chair) and syn(chair-chair), respectively. In the former coordination compound, Cu(I) is coordinated with two nitrogen and one sulfur atom of the ligand. In the latter one, Co(II) is coordinated with two nitrogen and two sulfur atoms of the ligand. In complexes I and II, the formation of three-dimensional structure depends on π-π-stacking and hydrogen bonds.