Trans-effect kinetic

Small particles, luminescence, 35 350-351 Smooth muscle light-chain kinase, 46 447-448 Sn, delocalization, 35 382 [Sn,(DIPT)J, 40 450 [SnCTIPTlj], 40 450 SO, -, 33 95-96 SO, -, chemistry, 33 93-94 SOj -, kinetic trans effect, 34 163 SO2, square-pyramidal adducts, 34 268 SOD, see under individual superoxide dismu-tases Sodium... 

VC13 treated with Bu NC produces mer-[VCl3(CNBu,)3]. The structure was determined by X-ray diffraction.182 The HNMR spectra in CDC13 showed that the free ligand exchanges more rapidly with the isocyanide tram to chloride than with the trans isocyanide groups. Therefore, the kinetic trans effect of chloride ion is larger than that of isocyanide. 

Table 17 The Kinetic trans Effect of Neutral Ligands...

In the kinetic trans effect, the departure of the trans ligand is probably aided by a stabilization of the transition state via the same mechanisms operative for the trans influence.114 Both associative and dissociative ligand substitution processes seem to be facilitated in this way.117... 

This ground-state phenomenon is known as the trans influence, and depends mostly on the a bonding capability and the polarizability of the ligand. Some ligands such as CN- do not show much trans influence but nevertheless have a large kinetic trans effect, because their p-acceptor properties help in the stabilisation of the transition state. 

Basolo and Pearson (5b) as part of a discussion of the kinetic trans effect (for definition see Ref. 5a) established a qualitative trans influence... 

It seems that the BAE and salen complexes are also labilized when they contain an alkyl ligand (60, 61). There are unfortunately no unambiguous data on the kinetic trans effect in the corrinoids. 

Substitution reactions of platinum(II) complexes containing one or more metal carbon bond(s) have a long history.217 Interest in such complexes and their reactivity is associated with their function as catalysts in synthetic procedures and in environmental applications. One important characteristic is the kinetic trans effect this is ascribed to the labilisation of a ra/is-positioned group caused by a C-bonded ligand,218 typically alkyl or aryl. In a mechanistic study in which kinetics measurements at elevated pressures were employed, cyclometallated Pt(II) complexes were used.219 The complex shown in Scheme 4 is water-soluble permitting the kinetics of substitution by a wide range of nucleophiles to be studied in aqueous solution. 

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