Mechanisms of metal complexes

On the basis of the available mechanistic information, a challenging question is to what extent can the substitution mechanism of metal complexes be adjusted by structural modifications of the systems. These usually involve the tuning of steric and electronic effects. A number of such examples are treated in the following sections. 

Robert W. Hay. Reaction Mechanisms of Metal Complexes. Albion/Harwood Pub 2000... 

Ultrasonic absorption played a major historical role in an understanding of the mechanisms of metal complex formation. It has also been used to study stereochemical change in metal... 

Hay R.W., Reaction Mechanisms of Metal Complexes, Horwood, Chichester, 2000. Cox B.G., Modem Liquid Phase Kinetics, Oxford University Press, Oxford, 1994. 

The remarkable chemical and coirfigurational stability of octahedral Cr complexes see Octahedral) was responsible for their role in the groundbreaking work of Alfred Werner, the father of modem coordination chemistry see Coordination Chemistry History). In the twentieth century, the same properties led to their use in studies of the reaction mechanisms of metal complexes. In recent years, the chemistry of the chromium carbon bond has been the most active area of research in chromium chemistry see Chromium Organometallic Chemistry), motivated in part... 

A consideration of the previous statements leads one to expect a relatively simple substitution chemistry for the alkali ions in solution. Due to their noble gas like electron configuration, the substitution rates should show a straightforward relationship to physical properties such as charge and size. However, it is naive to assume that complex formation involving main group metal ions is an easily resolved problem. There exist several non-trivial facts, which cannot readily be explained. It is a close examination of these, which will provide some interesting insight into the mechanism of metal complex formation of alkali ions. 

Normal-pulse polarography may be applied to solid-electrode voltammetry, which often is beset by electrode fouling (there is no periodic renewal of the electrode surface, as there is at the dme). This can be demonstrated for the electrolytic deposition of Ag and Au at solid electrodes and for the study of redox mechanisms of metal complexes ... 

Hay, R. W. Reaction Mechanisms of Metal Complexes Horwood Chichester, UK, 2000. 

Recent work in ultrafast IR studies has provided new insight into the mechanisms of metal complex radical generation and reactivity. Photochemical studies62 of Et-W (CO)3Cp have shown that the primary photochemical pathway was CO loss, as exemplified in Equation 10.43 for the methyl complex Me-W(CO)3Cp. A side reaction did produce radicals, but this may have occurred from vibrationally hot parent molecules. Both a and p C-H activation processes were observed. A general scheme elucidated for the ethyl complex is shown in Figure 10.3. 

R.W. Flay (2000) Reaction Mechanisms of Metal Complexes, Florwood Publishing Ltd, Chichester - Includes excellent coverage of substitution reactions, and isomerization, racemi-zation and redox processes. 

A form of EGA involves heating the sample at a constant rate in the probe of a mass spectrometer and the resulting TA technique is known as programmed probe analysis or more simply as analytical pyrolysis . By such a process, samples are pyrolyzed in high vacuum since the sample environment is equivalent to the operating pressure of the mass spectrometer. This technique has been used by Bratspies et al. to determine thermal decomposition mechanisms of metal complexes, particularly tin dithiocarba-mate complexes and this definitive study has been reviewed. 

KINETICS AND MECHANISM OF METAL-COMPLEX FORMATION IN AQUEOUS MICELLAR AND OIL INVERSE-MICELLAR SYSTEMS... 

Scheme 1 Mechanism of metal complex-mediated ATRA and ATRP reactions (Cf. Scheme 2 for a discussion of the terms used in this scheme).

In this chapter, we consider the mechanisms of metal complex catalysis. 

Figure 8.1 Mechanism of metal complex-mediated ATRA and ATRP.

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