Di‐μ‐pivalamidato‐κ4N:O;O:N‐bis­[(2,2′‐bi­pyridine‐κ2N,N′)(sulfato‐κO)­platinum(III)] tetrahydrate in a head‐to‐tail isomerism

The title compound, Pt₂^III(C₅H₁₀NO)₂(SO₄)₂(C₁₀H₈N₂)₂]·4H₂O, is the first reported example of a complex in which an amidate‐bridged Pt(bpy) dimer is stabilized in the oxidation level of Pt^III (bpy is 2,2′‐bi­pyridine). The asymmetric unit consists of one half of the formula unit with a twofold axis passing through the center of the dimer. The intradimer Pt^III—Pt^III bond distance 2.5664 (6) Å] is comparable to those reported for α‐pyridonate‐bridged cis‐diammineplatinum(III) dimers 2.5401 (5)–2.5468 (8) Å; Hollis & Lippard (1983). Inorg. Chem. 22 , 2605–2614], in spite of the close contact between the bpy planes within the dimeric unit. The axial Pt—O_sulfate distance is 2.144 (7) Å.