Synthesis and Crystal Structures of Silver Thianthrene Complexes with Weakly Coordinating Anions

Abstract

Two novel silver complexes with thianthrene (TA) as a ligand have been synthesized in the poorly coordinating solvent liquid sulfur dioxide, using silver salts with weakly coordinating anions [BF4]− and [SbF6]−. Both colorless compounds contain discrete molecular entities and SO2 molecules included in the crystal structure. Selection of crystals and the diffraction data collection were performed at low temperatures (123 K). The tris(μ-thianthrene-κ2S)disilver(I) bis(hexafluoroantimonate) sulfur dioxide solvate [Ag2(TA)3][SbF6]2·5SO2 (1) (monoclinic, P21/c, a = 21.644(3), b = 12.4216(4), c = 21.934(3) Å , β = 115.04(1)°, Z = 4) is made up of complexes bearing three TA units acting as bridging ligands with both S atoms towards two Ag+ ions with d(Ag+-Ag+) = 2.911 Å giving the [Ag2(TA)3]2+ unit approximately D3h molecular symmetry. The bis(μ-thianthrene-κ2S)disilver(I) bis(tetrafluoroborate) sulfur dioxide solvate [Ag2(TA)2][BF4]2・3SO2 (2) (monoclinic, C2/c, a = 21.0045(6), b = 7.4553(2), c = 22.6024(6) A° , β = 109.65(0)°, Z = 4) is made up of [Ag2(TA)2]2+units with two bridging TA units coordinating two Ag+ ions with d(Ag+-Ag+) = 2.925 Å giving the complexes approximately D2h molecular symmetry. Weak, secondary bonds between Ag+ and the F atoms of the anions, such as Ag···F-SbF5 = 2.862(4) Å in 1 or Ag···F-BF3 = 2.773(2) Å in 2, and with O atoms of SO2 molecules link the complexes with the anions and the solvate molecules, respectively.