Dehydrohalogenation and dimeric complex formation proceeded at the solid-phase heating of trans-[Pt(3-methyl-4-acetyl-5- aminopyrazole)(dimethyl sulphoxide)Cl 2]. X-ray structure of the DI-μ-N 1,N 2-(3-methyl-4-acetyl- 5-aminopyrazolate)bis(dimethyl sulphoxide)dichlorodiplatinum(II)

Abstract

The bridge-splitting reaction of [Pt(Me 2SO)(μ,Cl)Cl] 2 with 3-methyl-4-acetyl-5-aminopyrazol (R 3PzH) in acetone leads to the formation and isolation of the trans-[Pt(Me 2SO)(R 3PzH)Cl 2] complex. On heating, in the solid phase trans-[Pt(Me 2SO) (R 3PzH)Cl 2] undergoes thermal conversion with the formation of[Pt 2(R 3Pz) 2(Me 2SO) 2Cl 2] and the abstraction of HCl. The structure of the complex [Pt 2(R 3Pz) 2(Me 2SO) 2Cl 2] was determined by X-ray diffraction analysis. The complex exhibits a head-to-tail dimeric structure with two bridged pyrazolate anions. The dimerization reaction studied represents an unusual type of the solid-phase conversion of platinum complexes, which can be considered as a variant of the “Anderson rearrangement”.