Acids examples

On treatment with the appropriate nucleophile an acyl chlonde may be converted to an acid anhydride an ester an amide or a carboxylic acid Examples are presented m Table 20 1... 

Acyl derivatives, RCO—NH—OH and HjN—O—CO—R, are named as A-hydroxy derivatives of amides and as O-acylhydroxylamines, respectively. The former may also be named as hydroxamic acids. Examples are A-hydroxyacetamide for CH3CO—NH—OH and O-acetylhydrox-ylamine for HjN—O—CO—CH3. Further substituents are denoted by prefixes with O- and/or A-locants. For example, C5H5NH—O—C2H5 would be O-ethyl-A-phenylhydroxylamine or A-ethox-ylaniline. 

The reaction vessel (nitrator) is constructed of cast iron, mild carbon steel, stainless steel, or glass-lined steel depending on the reaction environment. It is designed to maintain the required operating temperature with heat-removal capabiUty to cope with this strongly exothermic and potentially ha2ardous reaction. Secondary problems are the containment of nitric oxide fumes and disposal or reuse of the dilute spent acid. Examples of important intermediates resulting from nitration are summarized in Table 3. 

The reaction of peracids with ketones proceeds relatively slowly but allows for the conversion of ketones to esters in good yield. In particular, the conversion of cyclic ketones to lactones is synthetically useful because only a single product is to be expected. The reaction has been carried out with both percarboxylic acids and Caro s acid (formed by the combination of potassium persulfate with sulfuric acid). Examples of both procedures are given. 

Determine equilibrium constants for the reaction of amines with strong or weak acids. (Example 22.8 Problems 27,28) 27... 

Cathodic inhibitors are passivating inhibitors they raise the hydrogen overvoltage, thus impeding the reduction of hydrogen ions at the cathode. They are suitable for inhibiting sulfuric or phosphoric acids. Examples are benzotriazole (at low concentrations) and alkylamines. 

A species consisting of several ligands (the Lewis bases) that have an independent existence bonded to a single central metal atom or ion (the Lewis acid). Examples (1) H,N—BF, (2) [Fe(H2())J,l PtCl4. composite material A synthetic material composed of a polymer and one or more other substances that have been solidified together. 

Conversion of the unknown to, or formation of the unknown from, a compound of known configuration without disturbing the chiral center. See the glyceraldehyde-glyceric acid example above (p. 138). Since the chiral... 

By recognizing species in solution and their dominant equilibrium, we can construct titration curves for other diprotic acids. Example shows how this is done for sulfurous acid. 

The permeabilities of the acid examples rise with increasing phospholipid content, up to 20% lipid, with rank ordering preserved. Naproxen and ketoprofen... 

The permeabilities of the acid examples rise with increasing phospholipid content, up to 20% lipid, with rank ordering preserved (data not shown). Naproxen and ketoprofen show the most dramatic increases in going from 2% to 10% lipid membranes - somewhat higher in soy than in egg. Piroxicam shows less... 

A donor atom is the atom in the ligand that donates shares in electron pairs to a metal, a Lewis acid. Examples of elements capable of being donor atoms in coordination compounds include O, N, P, F, Cl, Br, I, and C. They all have at least one lone pair of electrons to donate to a metal. 

Aldehydes, therefore, can also be oxidised to carboxylic acids. Example... 

Proton donor (Bronsted-Lowry acid) example carboxylic acid... 

Transmetallation with metallic electrophiles has also received a lot of attention, often with the aim of making polyfunctional Lewis acids. Examples are shown in Table 2. 

The method has been employed for glyceraldehyde-glyceric acid example. The process can be repeated further and the configurations of many other compounds can be correlated with either glyceraldehyde or glyceric acid. 

There is obviously a relation with the classic activation of molecules by Lewis acids, but here we have confined ourselves to the activation of "soft" substrates by "soft" acids. Examples of "hard" acid activated reactions include Diels-Alder additions, nitrile solvolysis, ester solvolysis, ester formation, Oppenauer reactions etc (see Lewis acid catalysed reactions, 2.11). 

There are 20 common amino acids in the human body. All amino acids contain a carboxylic acid group and an amino group. Amino acids can be linked by amide bonds to form proteins. Each amino acid has a different side chain, which is attached to the centre carbon atom. Figure 2.16, below, shows the structure of an amino acid. The letter G represents the side chain of the amino acid. Examples of side chains include —CH3 (for the amino acid alanine), —CH2CH2CONH2 (for glutamine), and —CH2OH (for serine). 

Cation derived from a weak base Reaction with water only the cation Solution acidic Examples NH4CI, NH4NO3, NH4CIO4 Reaction with water both ions Solution neutral if ka = kb, acidic if ka> kb, basic if kb > ka Examples NH4CN (basic), (NH4)2S (basic), NH4NO2 (acidic)... 

This is essentially the same as the tartaric acid example, without the conformational complication. Thus, there are two chiral centres, and the groups around each centre are the same. Again, we get only three stereoisomers rather than four, since the cis compound is an optically inactive meso compound. There is a plane of symmetry in this molecule, and it is easy to see that one chiral centre is mirrored by the other, so that we lose optical activity. 

An acid/base theory stating (a) that an acid is any substance that tends to donate or release protons (also called hydrogen ions) to a base, and (b) that a base is a substance that accepts or removes protons from an acid. Examples of Brpnsted acids include H3O+, H2O, CH3COOH, and HS04 . Examples of Brpnsted bases include H2O, OH", CH3COO, and SO42. ... 

Oxidative cleavage of alkynes by a variety of reagents has been reviewed [35, 60, 70, 71]. In most cases the CC bond is broken, but in some cases a-diketones are formed instead of, or in addition to, carboxylic acids. Examples of both types of reaction are given in Tables 3.3 and 3.6. 

An alternative to the introduction of structural changes to increase reactivity is to raise the temperatures of the cyclization either through use of a sealed tube (example 15) or by use of polyphosphoric acid (examples 16 and 17). 

Condensed tannins are complex polymers, where the building blocks are usually catechins and flavonoids, esterihed with gallic acid. Example epicatechin trimer. 

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