Synthesis and Crystal Structures of S 2 O 2 Macrocycle L, and its Silver(I) and Platinum(II) Complexes (Where L = 5,8-dioxa-2,11-dithia-[12]-o-cyclophane)

The S₂O₂-donor macrocycle, L(5,8-dioxa-2,11-dithia-12]-o-cyclophane or 3,4-benzo-1,6-dithia-9,12-dioxocyclo-tetradecane-3-ene) was synthesized by ring closure reaction of 2,2'-(ethylenedioxy)diethanethiol with ,'-dibromo-o-xyleneunder high dilution and crystallized from methanol. The X-ray structure of L has a C₂ axis and is shown to have two S atoms oriented exodentate and two O atoms positionedendodentate to the ring cavity. Reaction of AgNO₃ with L affords monomeric Ag(L)(NO₃)], (1)in which the Ag atom is in a distorted trigonal plane coordinated by two S atoms in a ring and to one O atom from the NO₃ ^- ion. The behavior of complex 1 in solution was also characterized by NMR titration. Reaction between K₂PtCl₄ and L affords Pt(L)Cl₂], (2) in which the Pt atom has a distorted square-planar environment, coordinated to two S atoms of Land to two Cl^- ions in a cis arrangement.