Volumes of activation for the substitution reactions of cis- and trans-[PtL2(Cl)X] with pyridine in various solvents

Influence of Solvent on Ligand‐Substitution Reactions of PtII Complexes as Function of the ‐Acceptor Properties of the Spectator Chelate

“…On changing the solvent to methanol, ethanol, 1-propanol and 1-pentanol, an acceleration of all substitution reactions for the complexes apa, pap and ppp was observed. This tendency was also observed by Kotowski et al [9] for substitution reactions on related Pt II complexes. Various attempts were undertaken to correlate the reported secondorder rate constants with physical parameters that describe the solvent properties.…”

“…[7] Kotowski et al determined rate and activation parameters for the reaction of trans-[Pt(py) 2 (NO 2 )Cl] with pyridine in nitromethane, methanol, ethanol and dichloromethane. [8,9] The solvent dependence of the activation volume, ΔV ϶ , could be used to separate intrinsic and solvational volume contributions which result from changes in bond lengths and angles, and changes in polarity, dipole interactions and electrostriction during formation of the transition state of the reaction, respectively. Such information is crucial for a full understanding of the intimate nature of the substitution mechanism.…”

“…Such information is crucial for a full understanding of the intimate nature of the substitution mechanism. [8,9] In this paper we report the effect of solvent on ligandsubstitution reactions of Pt II complexes as a function of the π-acceptor properties of the spectator chelate. The investigated reaction is given in Equation (1).…”

Substitution Reactions of cis‐ and/or trans‐Bromomesitylbis(triethylphosphine) Platinum (II) with Thiourea in Ethanol, Dimethylsulfoxide, and Acetone

“…Furthermore, changes in the dipole moments of these complexes during the activation process may be expected to be considerably smaller than for the substitution reactions of cis-and trans-[PtCl(NO,) (py),] with yyridine [S]. 1 1 1 the latter system, the dipole moments of the initial state species were substantially lower than those of the corresponding isomers of the title complex [8,101. Therefore, the development of a highly polar transition state gave risc to a large increase in electrostriction in the previous work [S], but is not expected to play such an important role here.…”

Application of High Pressure in the Elucidation of Inorganic and Bioinorganic Reaction Mechanisms

“…A high-pressure cell capable of being used for monitoring conductivity changes has been designed and constructed, 83 but not widely used. More recently, an updated version of a pill box-based high-pressure apparatus, in which detection has been extended from the UV/visible range to the near-IR region and for pressures up to 400 MPa has been described.…”