Silver(I) Sandwich Complexes of Oxa‐Crowned Derivatives of Dithiomaleonitrile

The coordination chemistry of the four oxa‐crowned derivatives of dithiomaleonitrile mn‐12S 2 O 2 , mn‐15S 2 O 3 , mn‐18S 2 O 4 , and mn‐21S 2 O 5 as well as of the acyclic bis(methylthio)maleonitrile mn‐S 2 with Ag I was investigated by X ray structural and spectroscopic methods. The 2:1 complexes (ligand/Ag I ) [Ag(mn‐12S 2 O 2 ) 2 ]PF 6 , [ 1 ]PF 6 , [Ag(mn‐15S 2 O 3 ) 2 ]PF 6 , [ 2 ]PF 6 , and [Ag(mn‐S 2 ) 2 ]PF 6 , [ 6 ]PF 6 , and the 1:1 complexes [Ag(mn‐15S 2 O 3 )]ClO 4 , [ 3 ]ClO 4 , [Ag(mn‐18S 2 O 4 )]PF 6 , [ 4 ]PF 6 , and [Ag(mn‐21S 2 O 5 )]PF 6 [ 5 ]PF 6 , were obtained with AgPF 6 or AgClO 4 in MeOH. The stoichiometry of the macrocyclic Ag I complexes and the coordination mode of mn‐S 2 O n +1 coronands ( n = 1–4) is determined by the length of the macrocyclic oligoethylene chain. – The mn‐crown dithioethers mn‐12S 2 O 2 and mn‐15S 2 O 3 form with AgPF 6 the new sandwich complexes [Ag(mn‐12S 2 O 2 ) 2 ]PF 6 , [ 1 ]PF 6 , and [Ag(mn‐15S 2 O 3 ) 2 ]PF 6 , [ 2 ]PF 6 . [ 1 ]PF 6 crystallises in the triclinic space group P 1. In the centrosymmetric cation [ 1 ] + each mn‐12S 2 O 2 ligand is coordinated to the Ag I centre in an endo manner via both S atoms and one O atom. The distance of the second O atom of mn‐12S 2 O 2 to Ag I is somewhat longer than a normal Ag–O ether bond. The overall environment around Ag I in [ 1 ] + is that of a distorted cubic S 4 O 4 set of donors. [ 2 ]PF 6 crystallises in the monoclinic space group C 2/ c . In the centrosymmetric cation [ 2 ] + silver(I) is planar‐coordinated by the four S atoms of both mn‐15S 2 O 3 molecules. The six O atoms of both mn‐15S 2 O 3 ligands show only long‐range interactions to the Ag I ion. They surround Ag I almost vertically to the planar S 4 set of donors in a crown‐like manner. – The crystal structures of the 1:1 complexes [Ag(mn‐18S 2 O 4 )]PF 6 , [ 4 ]PF 6 , and [Ag(mn‐21S 2 O 5 )]PF 6 , [ 5 ]PF 6 , consist of linear chain polymers. [ 5 ]PF 6 forms an N‐bridged chain polymer of endocyclic [Ag(mn‐21S 2 O 5 )] + units with S 1 O 4 N Nitrile coordination at the Ag I centre. In the 2:1 complex [Ag(mn‐S 2 ) 2 ]PF 6 , [ 6 ]PF 6 , each mn‐S 2 acts as a monodentate N Nitrile donor. – 13 C‐NMR studies in nitromethane solution confirm that the Ag I ions in the complexes of the mn‐crown dithioethers remain coordinated. However, the Ag I ion in complex of mn‐S 2 is decoordinated.