Crystal structures of three copper(II)–2,2′-bipyridine (bpy) compounds, [Cu(bpy)2(H2O)][SiF6]·4H2O, [Cu(bpy)2(TaF6)2] and [Cu(bpy)3][TaF6]2 and a related coordination polymer, [Cu(bpy)(H2O)2SnF6]n

Abstract

We report the hydrothermal syntheses and crystal structures of aquabis(2,2′-bipyridine-κ2N,N′)copper(II) hexafluoridosilicate tetrahydrate, [Cu(bpy)2(H2O)][SiF6]·4H2O (bpy is 2,2′-bipyridine, C10H8N2), (I), bis(2,2′-bipyridine-3κ2N,N′)-di-μ-fluorido-1:3κ2F:F;2:3κ2F:F-decafluorido-1κ5F,2κ5F-ditantalum(V)copper(II), [Cu(bpy)2(TaF6)2], (II), tris(2,2′-bipyridine-κ2N,N′)copper(II) bis[hexafluoridotantalate(V)], [Cu(bpy)3][TaF6]2, (III), and catena-poly[[diaqua(2,2′-bipyridine-κ2N,N′)copper(II)]-μ-fluorido-tetrafluoridotin-μ-fluorido], [Cu(bpy)(H2O)2SnF6]n, (IV). Compounds (I), (II) and (III) contain locally chiral copper coordination complexes with C2, D2, and D3 symmetry, respectively. The extended structures of (I) and (IV) are consolidated by O—H...F and O—H...O hydrogen bonds. The structure of (III) was found to be a merohedral (racemic) twin.

Keywords

• crystal structure
• hydrothermal synthesis
• racemic compounds
• copper
• main group
• d0 early transition metal