Word Finder - derivatives

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Something derived.

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A word that derives from another one.

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A financial instrument whose value depends on the valuation of an underlying asset; such as a warrant, an option etc.

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A chemical derived from another.

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The derived function of a function (the slope at a certain point on some curve f(x))

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The value of this function for a given value of its independent variable.

Its methyl derivatives yield the corresponding carboxylic acids when oxidized by potassium permanganate.

There are various haloid derivatives of sulphurous acid.

Paraffins are found in all crude oils, and olefines in varying proportions in the majority, while acetylene has been found in Baku oil; members of the benzene group and its derivatives, notably benzene and toluene, occur in all petroleums. Naphthenes are the chief components of some oils, as already indicated, and occur in varying quantities in many others.

The amino derivatives are stable bases which readily yield substitution derivatives when acted upon by the halogen elements.

Hydriodic acid and phosphorus at high temperature give a dihydro-compound, whilst sodium and alcohol give hexaand octo-hydro derivatives.

The metallic derivatives (phenolates, phenates or carbolates) of the alkali metals are obtained by dissolving phenol in a solution of a caustic alkali, in the absence of air.

The alkyl derivatives may be obtained by heating phenol with one molecular proportion of a caustic alkali and of an alkyl iodide.

Owing to their possession of this common property, these natural fatty bodies and various artificial derivatives of glycerin, which behave in the same way when treated with alkalis, are known as glycerides.

It is a most important synthetic reagent; with sodium or sodium ethylate it forms sodio-malonic ester, which reacts readily with alkyl halides, forming alkyl malonic esters, which are again capable of forming sodium derivatives, that by further treatment with alkyl halides yield the di-alkyl malonic esters.

His earlier work was mainly concerned with organic chemistry, and he published researches on picoline and its derivatives in 1876-78 and on quinine and its decomposition products in 1878-79.

The doctrine of copulae was discarded, and in 1859 emphasis was given to the view that all organic compounds were derivatives of inorganic by simple substitution processes.

An apt definition of organic chemistry is that it is "the study of the hydrocarbons and their derivatives."

We now proceed to discuss the types of aliphatic compounds; then, the characteristic groupings having been established, an epitome of their derivatives will be given.

In fact, the analogy between the alkyl groups and metallic elements forms a convenient basis from which to consider many derivatives.

Considering derivatives primarily concerned with transformations of the hydroxyl group, we may regard our typical acid as a fusion of a radical R CO - (named acetyl, propionyl, butyl, &c., generally according to the name of the hydrocarbon containing the same number of carbon atoms) and a hydroxyl group. By replacing the hydroxyl group by a halogen, acid-haloids result; by the elimination of the elements of water between two molecules, acid-anhydrides, which may be oxidized to acid-peroxides; by replacing the hydroxyl group by the group. SH, thio-acids; by replacing it by the amino group, acid-amides (q.v.); by replacing it by the group - NH NH2, acid-hydrazides.

A similar behaviour has since been noticed in other trimethylene derivatives, but the fact that bromine, which usually acts so much more readily than hydrobromic acid on unsaturated compounds,, should be so inert when hydrobromic acid acts readily is one still.

B aeyer has suggested that his hypothesis may also be applied to explain the instability of acetylene and its derivatives, and the still greater instability of the polyacetylene compounds.

From these nuclei an immense number of derivatives may be obtained, for the hydrogen atoms may be substituted by any of the radicals discussed in the preceding section on the classification of organic compounds.

It has already been stated that benzene derivatives may be regarded as formed by the replacement of hydrogen atoms by other elements or radicals in exactly the same manner as in the aliphatic series.

Important differences, however, are immediately met with when we consider the methods by which derivatives are obtained.

This compound is readily oxidized to benzoic acid, C 6 H 5 000H, the aromatic residue being unattacked; nitric and sulphuric acids produce nitro-toluenes, C6H4 CH3 N02j and toluene sulphonic acids, C 6 H 4 CH 3 SO 3 H; chlorination may result in the formation of derivatives substituted either in the aromatic nucleus or in the side chain; the former substitution occurs most readily, chlor-toluenes, C 6 H 4 CH 3 Cl, being formed, while the latter, which needs an elevation in temperature or other auxiliary, yields benzyl chloride, C 6 H 5 CH 2 C1, and benzal chloride, C 6 11 5 CHC1 2.

Of the tri-substitution derivatives, 1.2.3.-compounds are known as " adjacent " or " vicinal " (v), the 1.2.4 as " asymmetrical " (as), the 1.3.5 as " symmetrical " (s), of the tetrasubstitution derivatives, 1.2.3.4-compounds are known as " adjacent," 1.2.3.5 as " asymmetrical," and 1.2.4.5 as " symmetrical."

Thus in the tri-substitution derivatives six isomers, and no more, are possible when two of the substituents are alike; for instance, six diaminobenzoic acids, C 6 H 3 (NH 2) 2 000H, are known; when all are unlike ten isomers are possible; thus, ten oxytoluic acids, C 6 H 3 -CH 3.

Generally if any group be replaced by another group, then the second group enters the nucleus in the position occupied by the displaced group; this means that if we can definitely orientate three di-derivatives of benzene, then any other compound, which can be obtained from or converted into one of our typical derivatives, may be definitely orientated.

The orientation of higher substitution derivatives is determined by considering the diand tri-substitution compounds into which they can be transformed.

Of other syntheses of true benzene derivatives, mention may be made of the formation of orcinol or [3 s]-dioxytoluene from dehydracetic acid; and the formation of esters of oxytoluic acid (5-methyl3-oxy-benzoic acid), C6 H3 CH3.

For other syntheses of hexamethylene derivatives, see Polymethylenes.

If we accept Kekule's formula for the benzene nucleus, then we may expect the double linkages to be opened up partially, either by oxidation or reduction, with the formation of di-, tetra-, or hexa-hydro derivatives, or entirely, with the production of open chain compounds.

Decompositions of this nature were first discovered in the naphthalene series, where it was found that derivatives of indene (and of hydrindene and indone) and also of benzene resulted; Zincke then extended his methods to the disintegration of the oxybenzenes and obtained analogous results, R-pentene and aliphatic derivatives being formed (Rsymbolizing a ringed nucleus).

Hantzsch (Ber., 1889, 22, p. 1238) succeeded in ob R taining derivatives of o-diketo-R-hexene, which yield R-pentene and aliphatic compounds on decomposition.

The development of the " structure theory " in about 1860 brought in its train an appreciation of the chemical structure of the derivatives of benzene.

Baeyer pointed out that although benzene derivatives were obtainable from hexamethylene compounds, yet it by no means follows that only hexamethylene compounds need result when benzene compounds are reduced.

To follow Baeyer's results we must explain his nomenclature of the reduced benzene derivatives.

The proof of this statement rests on the fact that if the hydrogen atoms were not co-planar, then substitution derivatives (the substituting groups not containing asymmetric carbon atoms) should exist in enantiomorphic forms, differing in crystal form and in their action on polarized light; such optical antipodes have, however, not yet been separated.

Ladenburg's prism formula would give two enantiomorphic ortho-di-substitution derivatives; while forms in which the hydrogen atoms are placed at the corners of a regular octahedron would yield enantiomorphic tri-substitution derivatives.

Bamberger's observations on reduced quinoline derivatives point to the same conclusion, that condensed nuclei are not benzenoid, but possess an individual character, which breaks down, however, when the molecule is reduced.

During recent years an immense number of ringed or cyclic compounds have been discovered, which exhibit individual characters more closely resembling benzene, naphthalene, &c. than purely aliphatic substances, inasmuch as in general they contain double linkages, yet withstand oxidation, and behave as nuclei, forming derivatives in much the same way as benzene.

Thus benzene, (CH) gives thiophene, (CH) S, from which it is difficultly distinguished; pyridine, (CH) N, gives thiazole, (CH) N S, which is a very similar substance; naphthalene gives thionaphthen, C 11 S, with which it shows great analogies, especially in the derivatives.

The second method possesses greater advantages, for rings of approximate stability come in one group, and, consequently, their derivatives may be expected to exhibit considerable analogies.

The fifth compound, on the other hand, does not behave as an unsaturated aliphatic compound, but its deportment is that of a nucleus, many substitution derivatives being capable of synthesis.

Derivatives of osotriazol also exist in two forms - azimides and pseudo-azimides.

The first class includes those substances which require no preliminary treatment, and comprises the amides and ammonium compounds, pyridines, quinolines, alkaloids, albumens and related bodies; the second class requires preliminary treatment and comprises, with few exceptions, the nitro-, nitroso-, azo-, diazoand amidoazo-compounds, hydrazines, derivatives of nitric and nitrous acids, and probably cyanogen compounds.

The quinonoid structure of many coloured compounds has been proved experimentally, as, for example, by Hewitt for the benzene-azo-phenols, and Hantzsch for triaminotriphenyl methane and acridine derivatives; but, at the same time, many substances cannot be so explained.

On the chromophoreauxochrome theory (the nitro group being the chromophore, and the hydroxyl the auxochrome) it is necessary in order to explain the high colour of the metallic salts and the colourless alkyl and aryl derivatives to assume that the auxochromic action of the hydroxyl group is only brought strongly into evidence by salt formation.

Meyer formulated these compounds as nitroximes or nitro-isnitroso derivatives, viz.

Pyrrol is readily converted into pyridine derivatives by acting with bromoform, chloroform, or methylene iodide on its potassium salt, t3-brom-and O-chlorpyridine being obtained with the first two compounds, and pyridine itself with the last.

Staghounds are close derivatives of the bloodhound, and formerly occurred in England in two strains, known respectively as the northern and southern hounds.

Acetyland benzoyl-formaldoxime are derivatives of the threefold polymeric form.

Numerous derivatives of acetophenone have been prepared, one of the most important being orthoaminoacetophenone, NH2.C6H4.CO.CH3, which is obtained by boiling orthoaminophenylpropiolic acid with water.

Paal has also obtained pyrrol derivatives by condensing acetophenone-acetoacetic-ester with substances of the type NH2R.