The transition-metal complexes of the thiamacrocycle containing two ferrocene nuclei in the main chain. Synthesis, properties, and molecular structure of Ag(I), Cu(I), Pd(II), and Pt(II) complexes of 1,5,16,21-tetrathia[5.5]ferrocenophane

1,5,16,21-Tetrathia[5.5]ferrocenophane reacted with (MeCN)(4)CuClO4 and AgBF4 in THF to give the 1:1 complexes in good yields. The treatment of the ligand with (MeCN)(2)MCl2 (M = Pd and Pt) and two equivalents of AgBF4 in MeCN gave the 1:1 complexes in good yields. A reversible two-electron redox wave was observed near +0.3 V in the Cu(I) and Ag(I) complexes. The Pd(II) and Pt(II) complexes showed the irreversible two-electron oxidation wave near +0.7 V and that of the Pd(II) complex exhibited a slight peak separation, inferring a small interaction between the two Fe atoms through the central Pd(II) atom. As can be seen by X-ray analysis, the free ligand employed the pseudo-square conformation with regard to the thiamacrocycle in the molecular structure. The Pt(II) complex took the square-planar arrangement around the Pt(II) atom, while the Cu(I) and Ag(I) complexes maintained the tetrahedral configuration around the metal center. (C) 1998 Elsevier Science S.A. All rights reserved.