The nitro group has a very important action mainly on account of the readiness with which it can be introduced into the molecule, but its effect is much less than that of the azo group. The colour produced is generally yellow, which, in accordance with a general rule, is intensified with an increase in the number of groups; compare, for example, mono-, diand tri-nitrobenzene.
It is frequently used as a reducing agent: in acid solutions it reduces ferric to ferrous salts, arsenates to arsenites, permanganates to manganous salts, &c., whilst in alkaline solution it converts many organic nitro compounds into the corresponding amino derivatives.
For example: nitric acid and sulphuric acid readily react with benzene and its homologues with the production of nitro derivatives and sulphonic acids, while in the aliphatic series these acids exert no substituting action (in the case of the olefines, the latter acid forms an addition product); another distinction is that the benzene complex is more stable towards oxidizing agents.
From meta-brombenzoicacid two nitrobrombenzoic ac i ds are obtained on direct nitration; elimination of the bromine atom and the reduction of the nitro to an amino group in these two acids results in the formation of the same ortho-aminobenzoic acid.
Hence the positions occupied by the nitro groups in the two different nitrobrombenzoic acids must be symmetrical with respect to the carboxyl group. In 1879, Hubner (Ann., 1 95, p. 4) proved the equivalence of the second pair, viz.
Experience has shown that such mono-derivatives as nitro compounds, sulphonic acids, carboxylic acids, aldehydes, and ketones yield as a general rule chiefly the meta-compounds, and this is independent of the nature of the second group introduced; on the other hand, benzene haloids, amino-, homologous-, and hydroxy-benzenes yield principally a mixture of the orthoand para-compounds.
benzene and its homologues, carboxylic acids, and nitro compounds are much more stable towards oxidizing agents than.
The same difference attends the introduction of the methyl group into many classes of compounds, for example, the paraffins, olefines, acetylenes, aromatic hydrocarbons, alcohols, aldehydes, ketones and esters, while a slightly lower value (157.1) is found in the case of the halogen compounds, nitriles, amines, acids, ethers, sulphides and nitro compounds.
The principal chromophores are the azo, -N = N -, azoxy, = N 2 O, nitro, - N02, nitroso, - NO, and carbonyl, = CO, groups.
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, which are formed when nitrous acid acts on primary aliphatic nitro compounds.
The nitro group behaves very similarly to the hydroxyl group. The effect of varying the position of the nitro group in the molecule is well marked, and conclusions may be drawn as to the orientation of the groups from a knowledge of the crystal form; a change in the symmetry of the chemical molecule being often attended by a loss in the symmetry of the crystal.
They may also be prepared by the reduction of primary nitro compounds with stannous chloride and concentrated hydrochloric acid; by the reduction of unsaturated nitro compounds with minium amalgam or zinc dust in the presence of dilute acetic acid' Bouveault, Comptes rendus, 1902, 134, p. 1145):R2C:[[Chno 2 -R 2 C: Ch Nhoh - R 2 Ch Ch: Noh]], and by the action of alkyl iodides on the sodium salt of nitro-hydroxylamine (A.
NITRO COMPOUNDS, in organic chemistry, compounds containing the monovalent radical -NO 2 directly combined with carbon.
Aiphatic Nitro Compounds.-The nitroparaffins may be obtained by the action of the alkyl iodides on silver nitrite (V.
The nitro compounds of the lower members of the paraffin series cannot be prepared by the direct action of nitric acid on the hydrocarbons themselves, but, in the case of some of the higher members of the series direct nitration is possible (M.
The nitro compounds are colourless, somewhat pleasant smelling liquids, which distil without decomposition and possess boiling points much higher than those of the isomeric nitrous esters.
Hantzsch (Ber., 18 99, 3 2, pp. 577 et seq.) are probably derived from the isomeric iso-nitro compounds R: NO(OH), and thus the nitro derivatives are to be looked upon as pseudo-acids.
Meyer, Ber., 1891, 24, p. 3530), whilst the primary nitro cornpdunds on heating with hydrochloric acid yield hydroxylamine and an acid: CH 3 CH 2 NO 2 +H 2 0 = CH3 C02H+NH20H (V.
The hydrogen in the primary and secondary nitro compounds which is attached to the same carbon atom as the nitro group is readily replaced by bromine in alkaline solution.
The primary compounds form nitrolic acids of the type R C (: NOH) NO, the secondary yield pseudo-nitrols of the type RR': C(NO)(NO 2), whilst the tertiary nitro compounds are not acted upon by nitrous acid.
Aromatic Nitro Compounds.-The aromatic nitro compounds are generally obtained by the direct action of nitric acid.
Substitution takes place usually in the nucleus and only rarely in the side chain, and according to the conditions of the experiment and the nature of the compound acted upon, one or more nitro groups enter the molecule.
Nitro compounds have also been prepared by the action of cuprous oxide on diazonium salts (T.
The nitro group in the aromatic series is bound very firmly in the molecule and is not readily exchanged for other groups.
Several different products may be obtained by the reduction of the aromatic nitro compounds, the substances formed in any particular case depending on the conditions of experiment.
The electrolytic reduction of the aromatic nitro compounds gives rise to substituted hydroxylamines which are immediately transformed into aminophenols or amines.
It readily forms a sodium salt, from the aqueous solution of which on the addition of a mineral acid an isomeric solid form of the nitro compound (melting at 84° C.) is precipitated.
The products of the action of nitric acid on cellulose are not nitro compounds in the sense that picric acid is, but are nitrates or nitric esters.
In a similar manner, formic acid and dicyanophenylhydrazine yields a phenyl-triazole carboxylic acid, in which the phenyl group may be nitrated, the nitro group reduced to the amino group, and the product oxidized to a triazole carboxylic acid, which, by elimination of carbon dioxide, yields the free triazole: HO 2 C C=N H02C C =N, NPh-> N :CH N :CH They also result when the acidylthiosemicarbazides are strongly heated, the mercapto-triazoles so formed being converted into triazoles on oxidation with hydrogen peroxide (M.
It is readily nitrated to nitrobenzene, two, and even three nitro groups being introduced if some dehydrator such as concentrated sulphuric acid be present.
Concentrated nitric acid attacks them violently, producing various oxidation products, but if the amino group be "protected" by being previously acetylated, then nitro derivatives are obtained.
It is a powerful reducing agent, and is frequently employed for this purpose in organic chemistry; thus hydroxy acids are readily reduced on heating with the concentrated acid, and nitro compounds are reduced to amino compounds, &c. It is preferable to use the acid in the presence of amorphous phosphorus, for the iodine liberated during the reduction is then utilized in forming more hydriodic acid, and consequently the original amount of acid goes much further.
They may be prepared by the reduction of nitro compounds in alkaline solution (using zinc dust and alkali, or a solution of an alkaline stannite as a reducing agent); by oxidation of hydrazo compounds; or by the coupling of a diazotized amine and any compound of a phenolic or aminic type, provided that there is a free para position in the amine or phenol.
Azoxy Compounds, R N O N R', are usually yellow or red crystalline solids which result from the reduction of nitro or nitroso compounds by heating them with alcoholic potash (preferably using methyl alcohol).
Those not containing a nitro group may be prepared by the oxidation of the corresponding mixed hydrazo compounds with mercuric oxide.
The reverse series of operations was also carried out by the Fischers, triphenylmethane being nitrated, and the nitro compound then reduced to triaminotriphenylmethane or paraleucaniline, which on careful oxidation is converted into the dyestuff.
The third is also in the para position; for if benzaldehyde be condensed with aniline, condensation occurs in the para position, for the compound formed may be converted into para-dioxybenzophenone, C6H5CHO -)C6H5CH(C6H4NH2)2 - >C6H5CH(C6H40H)2 -->CO(C6H40H)2 but if para-nitrobenzaldehyde be used in the above reaction and the resulting nitro compound N02 C6H4 CH(C6H4NH2)2 be reduced, then pararosaniline is the final product, and consequently the third amino group occupies the para position.
With nitric acid in the presence of sulphuric acid it yields a nitro derivative.
NITROBENZENE, C 6 H 5 NO 2, the simplest aromatic nitro compound.
Nitro Compounds >>
Many derivatives are known, thus ortho-amino-benzophenone, melting at 106° C., can be obtained by reduction of the corresponding nitro compound; it condenses under the influence of heated lead monoxide to an acridine derivative and with acetone in presence of caustic soda it gives a quinoline.
NH 2 NH2 Diorthodiaminodiphenyl, -, isobtained bythe reduction of the corresponding nitro compound (obtained by the action of ethyl nitrite at o° C. on metadinitrobenzidine hydrochloride).
Somewhat later, they found that it could be prepared from diazobenzene imide, provided a nitro group were present in the ortho or para position to the diazo group. The para-nitro compound is dropped slowly into a cold solution of one part of caustic potash in ten parts of absolute alcohol; the solution becomes dark red in colour and is then warmed for two days on the water bath.
Like Clash Nitro, however, his efforts were considered insufficient to warrant further attention and money being spent on him.
nitro powered radio control cars, radio control cars with real working engines.
using nitro on the long straight in the rain put a big load on the graphics cards.
nitro groups make the ring much less reactive than the original benzene ring.
nitro boosts to improve the speed of your car.
nitro proof mark.
nitro compounds have been found in chronic, continuous treatment using high doses.
However, nitro groups make the ring much less reactive than the original benzene ring.
sporty handling as the Nitro, but seems like it climbs better.
In 1900 Bielefeldt found that a fulminate placed on top of an aromatic nitro compound, such as trinitrotoluene, formed a useful detonator; this discovery has been especially taken advantage of in Germany, in which country detonators of this nature are being largely employed.
It may be generally concluded that the substitution of alkyl, nitro, hydroxyl, and haloid groups for hydrogen in a molecule occasions a deformation of crystal structure in one definite direction, hence permitting inferences as to the configuration of the atoms composing the crystal; while the nature and degree of the alteration depends (1) upon the crystal structure of the unsubstituted compound; (2) on the nature of the substituting radicle; (3) on the complexity of the substituted molecule; and (4) on the orientation of the substitution derivative.
Tertiary nitro compounds may also be obtained by the oxidation of the corresponding amino-, hydroxyl amino-, and nitroso-hydrocarbons with monopersulphuric acid (E.
The primary and secondary nitro compounds (i.e.
It readily forms a sodium salt, from the aqueous solution of which on the addition of a mineral acid an isomeric solid form of the nitro compound (melting at 84Ã‚° C.) is precipitated.
By passing hydrochloric acid gas into an ethereal solution of the acids, the nitro group is eliminated and the hydrochloride of an oximido-acid is obtained (A.
He published at Oxford in 1668 two tracts, on respiration and rickets, and in 1674 these were reprinted, the former in an enlarged and corrected form, with three others "De sal-nitro et spiritu nitro - aereo," "De respiratione foetus in utero et ovo," and "De motu musculari et spiritibus animalibus" as Tractatus quinque medico-physici.
Many derivatives are known, thus ortho-amino-benzophenone, melting at 106Ã‚° C., can be obtained by reduction of the corresponding nitro compound; it condenses under the influence of heated lead monoxide to an acridine derivative and with acetone in presence of caustic soda it gives a quinoline.
NH 2 NH2 Diorthodiaminodiphenyl, -, isobtained bythe reduction of the corresponding nitro compound (obtained by the action of ethyl nitrite at oÃ‚° C. on metadinitrobenzidine hydrochloride).
Not as sporty handling as the Nitro, but seems like it climbs better.
Walker's last major film appearance came in 1998 as the voice of Nick Nitro in the animated movie Small Soldiers, alongside contemporary actors such as Denis Leary and Kirsten Dunst.
The answer to that question was that she was living her life with her husband, Jim Gillette from the rock band Nitro, and their two children, James and Rocco.
Due to the number of requests Jeannie Nitro has received for gothic clothing in larger sizes they have recently added a few selections in plus sizes which can be found among their popular items.
Need for Speed: Nitro: Hop into real sports car and put the pedal to the metal in this game from Electronic Arts.
The only exception was when I used the nitro option.
When you hit the nitro button, you used the full canister.
Crash Nitro Kart, Megaman Battle and Chase and Bomberman Kart are just a few.
Infinite Nitro: Get the fastest burst of speed continually.
This might sound like common sense, but don't forget about your nitro.
If you have to, use a nitro coming out of a sharp turn to get your speed back up.
What you have to do is use a nitro to pass a car and continuously block that car as it will try to regain the position.
When you hear the Nitro boost kicking in for your opponents, make sure you either match it or get in his way.
In Ridge Racer for the PSP, Drifting increases your Nitro meter.
Hitting the Right shoulder button engages your nitro.
Nitro kits cost more money than electric models.
Other styles to consider include the Cal Pak Nitro 26-inch Deluxe Rolling Duffle Bag and the Coleman Excursion 36-inch Wheeled Duffle Bag.
These nightly and sprightly creatures love designers like Jeannie Nitro who are notorious for taking gothness to the next level of bizarre.
The Nitro Circus cast is a group of athletes and stunt drivers who banded together for a reality TV show on MTV.
Though the show itself was canceled after two seasons, the Nitro Circus group has more in store for fans.
Nitro Circus began as a short series of episodes on Fuel TV in 2006.
Each member of the Nitro Circus cast has a unique personality and skill set.
DeChamp and Pastrana combine their talents and imagination to come up with many of the stunts seen on Nitro Circus.
He isn't as specialized in extreme sporting as the rest of the Nitro Circus crew, but he brings his sense of adventure to the show, often participating in stunts that require little more than nerves of steel.
Nitro Circus enjoyed two successful seasons on MTV, but was ultimately canceled in 2010.
The word usage examples above have been gathered from various sources to reflect current and historial usage. They do not represent the opinions of YourDictionary.com.