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Amines basic principles

The basic principle of all diazotizations of aromatic amines with a hydroxy- or a sulfonamido group in the 4-position relative to the amino group involves a deprotonation of the OH or NH group, respectively, after diazotization of the amino group. There is also a case of a deprotonation of a CH group in the 4-position of an aniline derivative, namely in the diazotization of 4-aminophenylmalononitrile (2.41) which, by the sequence of steps shown in Scheme 2-23, yields 3-diazo-6-dicyanomethylene-1,4-cyclohexadienone (2.42), as found by Hartzler (1964). This product can also be represented by a zwitterionic carbanion-diazonium mesomeric structure. [Pg.30]

Scheme 14 Basic principle of the hydroformylation/reductive amination... Scheme 14 Basic principle of the hydroformylation/reductive amination...
Abstract The basic principles of the oxidative carbonylation reaction together with its synthetic applications are reviewed. In the first section, an overview of oxidative carbonylation is presented, and the general mechanisms followed by different substrates (alkenes, dienes, allenes, alkynes, ketones, ketenes, aromatic hydrocarbons, aliphatic hydrocarbons, alcohols, phenols, amines) leading to a variety of carbonyl compounds are discussed. The second section is focused on processes catalyzed by Pdl2-based systems, and on their ability to promote different kind of oxidative carbonylations under mild conditions to afford important carbonyl derivatives with high selectivity and efficiency. In particular, the recent developments towards the one-step synthesis of new heterocyclic derivatives are described. [Pg.244]

Figure 2.8, is generated, presenting peaks correspondent to functional groups, such as epoxide, primary and secondary amines, and hydroxyl. The values of the absorption bands for these groups can be found in the papers referenced earlier. The basic principle of all these methods is the comparison between the spectrum of reference substances and spectra of the reactants and products of a curing reaction subjected to radiation. A qualitative and quantitative identification of the components is then possible. [Pg.89]

Fractional solidification and its applications to obtaining ultrapure chemical substances, has been treated in detail in Fractional Solidification by M.Zief and W.R.Wilcox eds, Edward Arnold Inc, London 1967, and Purification of Inorganic and Organic Materials by M.Zief, Marcel Dekker Inc, New York 1969. These monographs should be consulted for discussion of the basic principles of solid-liquid processes such as zone melting, progressive freezing and column crystallisation, laboratory apparatus and industrial scale equipment, and examples of applications. These include the removal of cyclohexane from benzene, and the purification of aromatic amines, dienes and naphthalene. [Pg.13]

This book does not follow a chronological sequence but rather builds up in a hierarchy of complexity. Some basic principles of 51V NMR spectroscopy are discussed this is followed by a description of the self-condensation reactions of vanadate itself. The reactions with simple monodentate ligands are then described, and this proceeds to more complicated systems such as diols, -hydroxy acids, amino acids, peptides, and so on. Aspects of this sequence are later revisited but with interest now directed toward the influence of ligand electronic properties on coordination and reactivity. The influences of ligands, particularly those of hydrogen peroxide and hydroxyl amine, on heteroligand reactivity are compared and contrasted. There is a brief discussion of the vanadium-dependent haloperoxidases and model systems. There is also some discussion of vanadium in the environment and of some technological applications. Because vanadium pollution is inextricably linked to vanadium(V) chemistry, some discussion of vanadium as a pollutant is provided. This book provides only a very brief discussion of vanadium oxidation states other than V(V) and also does not discuss vanadium redox activity, except in a peripheral manner where required. It does, however, briefly cover the catalytic reactions of peroxovanadates and haloperoxidases model compounds. [Pg.257]

The basic principle of this chemistry is that rf-alkene-Pd(II) complexes, usually generated in situ, are easily attacked by nucleophiles to form (T-alkyl-Pd species, which in turn are able to react further in a variety of ways. In general, several kinds of nucleophiles (e.g. alcohols, amines and enolethers) are able to attack the alkene complex intermediates in an intra- or intermolecular fashion. This article, however, focusses exclusively on intramolecular alkoxypalladations, i.e. transformations of the type 2 3, which are of particular synthetic relevance. [Pg.83]

Compare and contrast the dynamic kinetic resolution of amines with dera cemization. For each approach, outline the basic principle ofthe method and then suggest suitable biocatalyst/chemocatalyst combinations necessary for each process. [Pg.456]

Several different types of detectors have been used for the quantitation of the biogenic amines however, currently the most popular techniques are electrochemical detection and fluorescent detection, usually coupled with pre- or post-column derivatisation techniques. The specific details of these detection techniques are discussed elsewhere (Chapter 3) and in the present section only the basic principles as applied to the biogenic amines will be reviewed together with a comparison between the two techniques in terms of their respective advantages and disadvantages. [Pg.266]


See other pages where Amines basic principles is mentioned: [Pg.992]    [Pg.21]    [Pg.683]    [Pg.791]    [Pg.239]    [Pg.61]    [Pg.299]    [Pg.758]    [Pg.494]    [Pg.1060]    [Pg.48]    [Pg.663]    [Pg.1081]    [Pg.215]    [Pg.96]   
See also in sourсe #XX -- [ Pg.86 , Pg.424 , Pg.438 , Pg.451 ]

See also in sourсe #XX -- [ Pg.516 ]




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Amines basicity

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