Synthesis and X-ray structure of [Ag2(Ph2X2)4][AsF6]2(X = S or Se); six-membered silver–sulphur and silver–selenium rings

Abstract

The reaction of diphenyl disulphide with AgAsF₆ in liquid SO₂ leads to [Ag₂(Ph₂S₂)₄][AsF₆]₂- The X-ray structure [space group P, a= 10.902(4), b= 10.976(6), c= 13.308(7)Å, α= 112.82(4), β= 92.43(3), γ= 107.69(3)°, Z= 1, and R= 0.041 for 5 139 unique observed reflections] shows a centrosymmetric six-membered ring, in which two silver atoms are connected by two bridging Ph₂S₂ ligands; further unidentate sulphur ligands complete irregular three-co-ordination at silver. The analogous reaction with diphenyl diselenide leads to the isostructural [Ag₂(Ph₂Se₂)₄][AsF₆]₂[space group P, a= 10.676(3), b= 11.253(3), c= 13.625(4)Å, α= 66.40(2), β= 89.67(2), γ= 71.40(2)°, Z= 1, and R= 0.044 for 4 439 reflections].