A Diamagnetic Six-Coordinate Ag(III) Complex

Abstract

Abstract The octahedral complex AgIII(CF3)3tpy (2Ag), attainable from AgIII(CF3)3py (1Ag) and terpyridine (tpy), has been isolated and characterized using NMR spectroscopy and Sc-XRD. Strikingly, 2Ag proved to be diamagnetic and showed tridentate coordination of the tpy ligand, thus forging an unprecedented 20-valence-electron AgIII complex. A comparative structural and theoretical study on the bonding of 2Ag vs. the coinage metal analogues 2M has unveiled the preferred six-coordination in the lighter counterparts, 2Cu and 2Ag, while five-coordination is favored in 2Au. A rationale to the unexpected diamagnetism of 2Ag is also provided.