Applications in synthetic and analytical chemistry

Micelles exert large rate effects upon organic reactions and can in principle discriminate between different reactions, depending upon their charge type or molecularity. There are a number of examples of this type of discrimination in the literature, and they are easily explained in terms of the generally accepted models of kinetic micellar effects. 

Bimolecular E2 reactions involving OH in aqueous solution are speeded by cationic and inhibited by anionic micelles (Minch et al., 1975) whereas spontaneous reactions are generally inhibited strongly by cationic micelles and less strongly by anionic micelles it is therefore relatively easy to observe micellar control of product formation. 

In much the same way it should be possible to discriminate between attack by anionic and non-ionic nucleophiles. Micelles, regardless of charge, generally speed attack by non-ionic nucleophiles, but the enhancements are typically small, whereas large inhibition or enhancement is observed for attack of nucleophilic anions, depending upon micellar charge. 

Most studies of micellar effects upon rates or products of organic reactions have been made with very low concentrations of reactants, and this small scale of work is not very encouraging for the synthetic organic chemist. An additional disadvantage is that surfactants complicate product separation by extraction or distillation, and to date most studies in this general area have been exploratory and have been aimed at solving these problems. 

A limited degree of regioselectivity of aromatic chlorination in surfactant solutions has been observed (Jaeger and Robertson, 1977). Somewhat similar observations were made by Onyivruka et al. (1983) who also used n.m.r. spectroscopy to probe the substrate orientation, and they concluded that it controlled regioselectivity. 

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Applications in synthetic and analytical chemistry 279 Acknowledgements 281 Appendix 282... 

In the first part of the present review, new techniques of preparation of modified electrodes and their electrochemical properties are presented. The second part is devoted to applications based on electrochemical reactions of solute species at modified electrodes. Special focus is given to the general requirements for the use of modified electrodes in synthetic and analytical organic electrochemistry. The subject has been reviewed several times Besides the latest general review by Murray a number of more recent overview articles have specialized on certain aspects macro-molecular electronics theoretical aspects of electrocatalysis organic applicationssensor electrodes and applications in biological and medicinal chemistry. 

Ozonolysis has both synthetic and analytical applications m organic chemistry In synthesis ozonolysis of alkenes provides a method for the preparation of aldehydes and ketones... 

The Patai Series publishes comprehensive reviews on all aspects of specific functional groups. Each volume contains outstanding surveys on theoretical and computational aspects, NMR, MS, other spectroscopical methods and analytical chemistry, structural aspects, thermochemistry, photochemistry, synthetic approaches and strategies, synthetic uses and applications in chemical and pharmaceutical industries, biological, biochemical and environmental aspects. 

Ozonolysis has both synthetic and analytical applications in organic chemistry. In synthesis, ozonolysis of alkenes provides a method for the preparation of aldehydes and ketones. When the objective is analytical, the products of ozonolysis are isolated and identified, thereby allowing the structure of the alkene to be deduced. In one such example, an alkene having the molecular formula CgHig was obtained from a chemical reaction and gave acetone and 2,2-dimethylpropanal as the products. 

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