Synthesis and Characterization of the First Acyl(hydrido)platinum(IV) Complexes

The platina-β-diketone [Pt₂{(COMe)₂H}₂(μ-Cl)₂] (1) reacts with 2,2‘-bipyridine (bpy), 4,4‘-dimethyl-2,2‘-bipyridine (me₂bpy), or 4,4‘-di(tert-butyl)-2,2‘-bipyridine (t-bu₂bpy) to give novel acyl(hydrido)platinum(IV) complexes [PtCl(H)(COMe)₂(NN)] (NN = bpy (2a), me₂bpy (2b), t-bu₂bpy (2c)). The complexes 2 show an astonishing thermal stability in the solid state up to 180 °C. They decompose with cleavage of acetaldehyde to form the acylplatinum(II) complexes [PtCl(COMe)(NN)] (3). The identities of 2 and 3 were determined by microanalysis and NMR (¹H, ¹³C) and IR spectroscopies. The crystal structure of [PtCl(H)(COMe)₂(t-bu₂bpy)] (2c) has been determined. The Pt−H bond distance was found to be 1.72(5) Å.