Premium
cis‐trans Isomerization of bis(Dialkylsulfide)Dihaloplatinum(II) Complexes in Solution
Author(s) -
Roulet Raymond,
Barbey Claude
Publication year - 1973
Publication title -
helvetica chimica acta
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.74
H-Index - 82
eISSN - 1522-2675
pISSN - 0018-019X
DOI - 10.1002/hlca.19730560707
Subject(s) - isomerization , chemistry , endothermic process , kinetics , ligand (biochemistry) , chloroform , solvent , medicinal chemistry , stereochemistry , photochemistry , catalysis , organic chemistry , biochemistry , physics , receptor , adsorption , quantum mechanics
The equilibrium energetics and the kinetics of cis ‐ trans isomerization of some bis(dialkylsulfide)dihaloplatinum(II) complexes have been examined by 1 H‐NMR. spectroscopy. The isomers are stable in chloroform but each form isomerizes to an equilibrium mixture when free dialkylsulfide is added. The cis to trans process is endothermic and the position of the equilibrium is markedly dependent on the nature of the donor atoms and of the solvent. The rate of isomerization of Pt(Me 2 S) 2 Cl 2 is first order in complex and in Me 2 S. The isomerization proceeds by a double displacement mechanism as it is shown that the tris(dimethylsulfide)chloroplatinum(II) cation is an isolable intermediate of the reaction. When free Me 2 S is added to trans ‐Pd(Me 2 S) 2 Cl 2 , isomerization does not occur and one observes instead a fast ligand exchange. Its mechanism is the usual associative one for substitutions in square planar d 8 complexes.