It is also formed when ortho-aminodiphenylamine is distilled over lead peroxide (0.
The more complex phenazines, such as the naphthophenazines, naphthazines and naphthotolazines, may be prepared by condensing ortho-diamines with ortho-quinones (0.
Hinsberg, Ann., 1887, 2 37, p. 340); by the oxidation of an ortho-diamine in the presence of a-naphthol (0.
Witt), and by the decomposition of ortho-anilido-(-toluidido- &c.)-azo compounds with dilute acids.
If alkyl or aryl-ortho-diamines be used azonium bases are obtained.
The mono-amino derivatives or eurhodines are obtained when the arylmonamines are condensed with orthoamino zo compounds; by condensing quinone dichlorimide or para-nitrosodimethyl aniline with monamines containing a free para position, or by oxidizing ortho-hydroxydiaminodiphenylamines (R.
It is formed by reducing diortho-dinitrodiphenyl with sodium amalgam and methyl alcohol, or by heating diphenylene-ortho-dihydrazine with hydrochloric acid to 150° C. It crystallizes in needles which melt at 156° C. Potassium permanganate oxidizes it to pyridazine tetracarboxylic acid.
By the action of dilute nitric acid; orthoand para-nitrophenols are obtained, the ortho-compound being separated from the para-compound by distillation in a current of steam.
Ortho-nitrophenol, C6H4.OH N02(1-2), crystallizes in yellow needles which melt at 45° C. and boil at 214°C. Para-nitrophenol, C6H4.
The ortho-acid, in the form of its aqueous solution, is sometimes used as an antiseptic, under the name of aseptol.
Xanthene, C13H100, may be synthesized by condensing phenol with ortho-cresol in the presence of aluminium chloride.
1.2 or 1.6, named ortho- (o), 1.3 or 1.5, named meta- (m), and 1.4, named para- compounds (p).
OH COOH, may be prepared; and the two other known oxybenzoic acids (ortho- and para-) may be converted into benzoic acid.
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.
3 and 5, by starting out with ortho-aminobenzoic acid, previously obtained by two different methods.
This substance readily yields ortho-oxybenzoic acid or salicylic acid, which on nitration yields two mononitro-oxybenzoic acids.
Thus potassium ortho-oxybenzoate is converted into the salt of para-oxybenzoic acid at 220 0; the three bromphenols, and also the brombenzenesulphonic acids, yield m-dioxybenzene or resorcin when fused with potash.
C. Graebe (Ann., 1869, 149, p. 22) orientated the ortho-compound or phthalic acid from its formation from naphthalene on oxidation; the meta-compound or isophthalic acid is orientated by its production from mesitylene, shown by A.
The diaminobenzene resulting from two of these acids is the ortho-compound; from three, the meta-; and from one the para-; this is explained by the following scheme: CH NH, NH, NH., IAO NH, N / NH HooCCNH, Cooh Nh, W.
A scheme such as the preceding one shows that the first dibrombenzene must be the ortho-compound, the second the meta-, and the third the para-derivative.
Starting with a monoderivative, we have seen that a substituent group may enter in either of three positions to form an ortho-, meta-, or paracompound.
CH CH HC, N CH HC CH HC HC HC Hcch Hc Ch Ch Kekule t i Dewar Ladenburg One of the earliest and strongest objections urged against Kekule's formula was that it demanded two isomeric ortho-di-substitution derivatives; for if we number the carbon atoms in cyclical order from i to 6, then the derivatives 1.2 and 1.6 should be different.'
He assumed that if we have one atom 1 It is now established that ortho compounds do exist in isomeric forms, instances being provided by chlor-, brom-, and amino-toluene, chlorphenol, and chloraniline; but arguments, e.g.
That 1.2 and 1.6 should be ortho-positions, 1.3 and 1.5 meta-, and 1.4 para-, and following out the transformation on the Ladenburg formula, then an ortho-dioxyterephthalic acid (IV) should result, a fact denied by experience, and inexplicable unless we assume a wandering of atoms. Kekule's formula (III), on the other hand, is in full agreement (Baeyer).
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.
Soc. Trans., 1902, p. 961) shows the proximity of the ortho-positions, but fails to explain the identity of 1.2 and 1.6 compounds.
The more important types are derived from aromatic nuclei, benzene, naphthalene, &c.; the ortho-di-derivatives of the first named, lending themselves particularly to the formation of condensed nuclei.
Thus ortho-phenylene diamine yields the following products: N H N ./`N; Xn NZ In some cases oxidation of condensed benzenoid-heterocyclic nuclei results in the rupture of the heterocyclic ring with the formation of a benzene dicarboxylic acid; but if the aromatic nucleus be weakened by the introduction of an amino group, then it is the benzenoid nucleus which is destroyed and a dicarboxylic acid of the heterocyclic ring system obtained.
Pyridine gives origin to: pyridazine or ortho-diazine, pyrimidine or metadiazine, pyrazine or para-diazine, osotriazine, unsymmetrical triazine, symmetrical triazine, osotetrazone and tetrazine.
Benzo-ortho-diazines exist in two structural forms, cinnolin and phthalazine; benzo-meta-diazines are known as quinazolines; benzo-para-diazines are termed quinoxalines; the dibenzo-compounds are named phenazines, this last group including many valuable dyestuffs - indulines, safranines, &c. In addition to the types of compounds enumerated above we may also notice purin, tropine and the terpenes.
A similar depression is presented by methyl alcohol (67°) and methyl ether (-23 °) Among the aromatic di-substitution derivatives the ortho compounds have the highest boiling-point, and the meta boil at a higher, or about the same temperature as the para compounds.
On long heating the syrup is partially converted into pyrophosphoric and metaphosphoric acids, but on adding water and boiling the ortho-acid is re-formed.
When boiled with water it forms the ortho-acid, and when heated to redness the metaacid.
On oxidation it yields ortho-carboxy-hydrocinnamic acid, HO 2 C C 6 H 4 CH 2 CH 2 C02H.
Of these, the 8-acid and Bronner's acid are of more value technically, since they combine with ortho-tetrazoditolyl to produce fine red dye-stuffs.
This view, which was specially supported by Gay-Lussac and Leopold Gmelin and accepted by Berzelius, necessitated that all acids were monobasic. The untenability of this theory was proved by Thomas Graham's investigation of the phosphoric acids; for he then showed that the ortho- (ordinary), pyroand metaphosphoric acids contained respectively 3, 2 and I molecules of " basic water " (which were replaceable by metallic oxides) and one molecule of phosphoric oxide, P2 05.
At a temperature of about 300-400° C. the alkyl chloride formed in this reaction attacks the benzene nucleus and replaces hydrogen by an alkyl group or groups, forming primary amines homologous with the original amine; thus methylaniline hydrochloride is converted into paraand ortho-toluidine hydrochloride, and trimethyl phenyl ammonium iodide is converted into mesidine hydriodide.
The ortho-compounds condense to azimido benzenes, the metacompounds yield azo-dyestuffs, and the para-compounds yield bis-diazo compounds of the type XN2ï¿½C6H4ï¿½N2X.
The ortho-body dissolves in cold dilute acids; the meta-body does not.
Anthracene has also been obtained by heating ortho-tolylphenyl ketone with zinc dust C6H4(CH CH =H20+C6H4 I)C6H4.
Ortho-cresol, CH 3 (1) C 6 H 4.
It may be prepared by fusion of ortho-toluene sulphonic acid with potash; by the action of phosphorus pentoxide on carvacrol; or by the action of zinc chloride on camphor.