Complexes of the Bicyclic Multifunctional Sulfur‐Nitrogen Ligand F 3 CCN 5 S 3 with Co 2+ , Zn 2+ , Cu 2+ , and Cd

The ability of the sulfur‐nitrogen‐carbon bicycle F 3 CCN 5 S 3 to act as a donor towards transition metal cations has been investigated. F 3 CCN 5 S 3 forms complexes with [M(SO 2 ) 2 ](AsF 6 ) 2 [M = Co, Cu, Zn, Cd] in the ratio 2:1 of the composition [M(F 3 CCN 5 S 3 ) 2 (OSO) 2 (FAsF 5 ) 2 ] [M = Co ( 1 ), Zn ( 3 )], [Cu(F 3 CCN 5 S 3 ) 2 (μ‐F)(μ‐F 2 AsF 4 )] 2 ( 4 ), and [Cd(F 3 CCN 5 S 3 )(μ‐F 3 CCN 5 S 3 )(η 2 ‐F 2 AsF 4 ) 2 ] 2 ( 5 ) in liquid sulfur dioxide. In the octahedral Co and Zn complexes F 3 CCN 5 S 3 coordinates as a monodentate ligand through the bridging nitrogen atom N5, which carries the highest negative charge according to theoretical calculations. With Cu 2+ a dinuclear structure with a central planar, four‐membered Cu 2 F 2 ring is formed, which has the shortest Cu ··· Cu distance of all structurally characterized Cu 2 F 2 units. Similar to the Co and Zn complexes, F 3 CCN 5 S 3 acts as a terminal monodentate ligand in the Cu compound. The reaction with the larger and softer Cd 2+ cation results in a dinuclear complex that contains terminal and bridging F 3 CCN 5 S 3 ligands. The bridging ligands coordinate through N5 and a nitrogen atom neighboring the carbon atom. In addition, a third weak bonding interaction between one fluorine atom of the trifluoromethyl substituent and the Cd 2+ center is observed. The formation of the different structures and the versatile coordination modes of the F 3 CCN 5 S 3 ligand are discussed. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)