Nitrato displacement in [Ag2(NO3)2(μ-dppf)2]. Molecular structure of a homoleptic dppf complex, [Ag2(μ-dppf)(dppf)2] (PF6)2 (dppf = 1,1′-bis(diphenylphosphino)ferrocene)

Abstract

Addition of 1,1′-bis(diphenylphosphino)ferrocene (dppf) to AgNO3 or [Ag2(NO3)2(μ-dppf)2] at room temperature gives rise to a homoleptic dppf complex [Ag2(μ-dppf)(dppf)2]2+ 1. Single-crystal X-ray diffractometric analysis of its PF6 - salt revealed a dinuclear structure with dppf singly and symmetrically bridging two trigonal planar AgI centres each of which contains a chelating dppf. The chelate angle [105.6(2)°] is significantly more acute than the PAgP angles subtended between the chelate and the bridging ligands [127.2(2)°]. Complex 1 reacts further with dppf to yield a bis(chelate) complex [Ag(dppf)2](PF6). Metathetic reactions of [Ag2(NO3)2(μ-dppf)2] with Na+ or K+ salts of X- (X Cl, OCN, SCN, Et2NCS2) at room temperature readily give good yields of, respectively, [Ag(μ-Cl)(μ-dppf)]4, [Ag2(μ-NCO,N)2(μ-dppf)2], [Ag2(μ-SCN- S,N)2(dppf)2], and [Ag2(S2CNEt2)2(μ-dppf)2]. © 1994.