The Mercury(II) Trifluoroacetate–Bipyridyl System

Three complexes of mercury(II) trifluoroacetate and 2,2′-bipyridyl, of different stoichiometry, have been investigated and their structures compared with the previously published structure of bis[(2,2′-bipyridyl­N,N')bis(trifluoroacetato­O)mercury(II)], [Hg(C2F3O2)2(C10H8N2)]2 (BHG). The complete series, AHG {(2,2′-bipyridyl­N,N')(trifluoroacetato­O)mercury(II) hemi[tetrakis(trifluoroacetato­O)mercury(II)], [Hg(C2F3O2)(C10H8N2)][Hg(C2F3O2)4]0.5}, BHG, GHG {bis­(2,2′-bipyridyl­N,N')(trifluoroacetato­O)mercury(II) (2,2′-bipyridyl­N,N')tris(trifluoroacetato­O)mercury(II), [Hg(C2F3O2)(C10H8N2)2][Hg(C2F3O2)3(C10H8N2)]}, and DHG {bis(2,2′-bipyridyl­N,N')mercury(II) bis(trifluoroacetate), [Hg(C10H8N2)2](C2F3O2)2}, shows the progressive replacement of trifluoroacetate by the bidentate 2,2′-bipyridyl. Within the series, mercury may be coordinated to zero, one or two bidentate bipyridyl groups. In the extreme case, i.e. DHG, the complex ion [Hg(bipyridyl)2]2+ is formed with exclusion of trifluoroacetate from the mercury coordination.