Synthesis and reactivity of bis(o-nitrophenyl)platinum. X-Ray crystal and molecular structure of [Pt{o-C6H4N(O)O}(o-C6H4NO2)(PPh3)]

Reaction of [Hg(o-C6H4NO2)2] with K2[PtCl4] or PtCl2(2 : 1) yields the complex [P[graphic omitted]}2]. It reacts (i) with monodentate ligands L (PPh3, AsPh3, or pyridine)(1 : 1) to give complexes of the type [[graphic omitted]}(o-C6H4NO2)L] or (ii) with monodentate L (PPh3, AsPh3, pyridine, or CO)(1 : 2) or bidentate ligands L2[cyclo-octa-1, 5-diene, 1,10-phenanthroline, 2, 2′-bipyridine, 1, 2-bis(diphenylphosphino)ethane, or bis(diphenylphosphino)methane](1 : 1) to give complexes [Pt(o-C6H4NO2)2L2]. The crystal structure of [[graphic omitted]}(o-C6H4NO2)(PPh3)] shows both chelating and monodentate o-nitrophenyl groups. They show no significant differences in the bond lengths Pt–C [2.018(9) and 1.983(8)Å, respectively] and N–C [1.446(11) and 1.468(12)Å, respectively]. The co-ordinated oxygen atom has a longer N–O bond length [1.273(10)Å] than the unco-ordinated one [1.221(10)], cf. those in the unco-ordinated o-nitrophenyl group [1.220(10) and 1.230(11)Å].