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therefore a metadiamine, and the 7-compound must, accordingly,
contain the nitroxyl groups in the para-position.

Trinitroparaxylene, C 6 H(CH 3 ) 2 'N0 2 ) 3 (1:4:2:3: 5), may
readily be prepared by nitrating with a mixture of nitric and
sulphuric acids, the whole being gently heated at the close of the
operation. It crystallizes from alcohol in stellate aggregates of
dazzling white needles, which melt at 139 140 . 1



XYLENESULPHONIC ACIDS, C 6 H 3 (OH 3 ) 2 S0 3 H.

2212 Orthnxylenesulphonic acid (1:2:4) is formed by dis-
solving orthoxylene in tolerably hot sulphuric acid. It crystal-
lizes from a somewhat dilute acid solution with two molecules
of water in long, rectangular tablets or thicker, flat prisms with
pointed ends. Its salts crystallize extremely well. When its
potassium salt is heated with sodium formate, paraxylic acid is
formed.

Scdium orthoxylenesulphonate, C 6 H 2 (CH 3 ) 2 S0 3 Na + 5H 2 O,
separates from a concentrated solution in flat prisms, the size of
which seems only to be limited by that of the containing vessel ;
they soon effloresce on exposure to the air.

Orthoxylenesulphonic chloride, C 6 H 3 (CH 3 ) 2 SO 2 C1, crystallizes
from ether in prisms, melting at 51 52.

Orthoxylenesulphonamide, C 6 H 3 (CH 3 ) 2 SO 2 .NH 2 , separates from
hot alcohol in prisms, which melt at 144 . 2

a-Metaxylenesulphonic acid (1:3:4) is formed, together with
a small quantity of the isomeric compound, when metaxylene is
dissolved in sulphuric acid. It separates on the addition of a
little water in large plates or prisms, which contain two molecules
of water. Xylic acid is formed when potassium salt is heated
with sodium formate (p. 391).

Sodium metaxylenesulphonate, C 6 H 3 (CH 3 ) 2 SO 3 Na, crystallizes
from water in scales, and from alcohol in small plates possessing
a silver lustre.

a-Metaxylenesulphonic chloride solidifies in the cold to a radiating
mass, or to prisms which melt at 34.

1 Fittig and Glinzer ; Noltiug aiicl Geissmann, Bcr. Detitsch. Chem. Gcs. xix.
144. 2 Jacobsen, ibid. x. 1010 ; xi. 22.



XYLENOLS. 399



a-Metaxylencsulphamide crystallizes from water iu lung
pointed needles and melts at 137.

v- Metaxylenesulphonic acid (1:3:2) has not been prepared
pure; its calcium salt when heated with sodium formate yields
a xylic acid, which decomposes on distillation with lime
into carbon dioxide and metaxylene. Its chloride is an oily
liquid, and the amide crystallizes in neeJles, melting at
95 9C. 1

Paraxylcncsulphonic acid is formed when paraxylene is dis-
solved at a gentle heat in slightly fuming sulphuric acid. It
crystallizes with two molecules of water in large plates or very
long, flat prisms.

Sodium paraxylenesulphonate, C 6 H 3 (CH 3 ') 2 S0 3 Na + H.,0, crys-
tallizes in large, flat, striated prisms, which do not effloresce in
the air.

Paraxylenesulplumic chloride forms flat prisms, which melt
at 24 26

' Paraxylenesulphamide is readily soluble in alcohol, slightly
in boiling water, from which it crystallizes in splendid, long
needles, melting at 147 148 (Jacobsen).



HYDROXY-XYLENES, OR XYLENOLS,

C 6 H 3 (CH 3 ) 2 OH.

2213 After Dusart, Kekule and Wurtz had shown that
fiulphonie acids are converted into phenols by fusion with potash,
the last-named of these chemists applied the reaction to xylene,
and discovered the interesting fact that this hydrocarbon yields
two isomeric phenols, a solid and a liquid xylenol. This iso-
merism is explained by him as due to the different positions of
the hydroxyl with relation to the two methyl groups. " This
isomerism," he adds, " could, according to Kekule's beautiful
theory, also exist in xylene itself, as a result of a different
arrangement of the side chains in the nucleus." 2 After this
supposition had been proved correct and these xylenes were
known, it was seen that six xylenols must exist, and these have
all now been prepared. Jacobsen obtained four of them from

1 Jacobsen, Ann. Chan. Pharm. clxxxiv. 188 ; loc. cit.

8 Ann. Chcm. Pharm. cxlvii. 372 : see also Wroblewsky, Zeitsclir. Chem. 1868)
23.



400 AROMATIC COMPOUNDS.



the sulphonic acids just described, 1 and the two others have been
prepared from the xylidines by means of the diazo-reaction. 2
Like ordinary phenol, they readily form tribromo-derivatives.

The xylenols also occur in coal-tar. They have not, in-
deed been isolated, but their derivatives have been prepared
from it.

The tar obtained as a by-product from blast furnaces
which are worked with coal seems to be especially rich in
xylenols ; the creosote oil fraction, boiling at 210 240, when
distilled over heated zinc dust, yielded a mixture of hydrocarbons,
which consisted chiefly of metaxylene. 3

a-Orthoxylenol (1:2:4) crystallizes from hot water in very
long needles and from very dilute alcohol in rhombic pyramids,
melting at 62'5 ; 4 it boils at 225 and forms an aqueous solution
which is not coloured by ferric chloride.

a-Tribromorthoxylenol, C 6 Br 3 (CH 3 ). 2 OH, crystallizes from
alcohol in fine, snow-white, matted needles, melting at 169.

v-Orthoxylenol (1:2:3) crystallizes from water in white
needles, melts at 75 and boils at 218; its aqueous solution
is coloured blue by ferric chloride, but is not affected by
bleaching-powder solution.

a-Mdaxylenol (1:3:4) is, according to Jacobsen, a strongly
refractive liquid, which smells like phenol, boils at 2 11 '5 and
.becomes viscid at 20, without, however, solidifying. These are
also the properties of the liquid xylenol discovered by Wurtz,
while Stadel and Holz showed that the xylenol prepared from
pure a-metaxylidine solidifies at the ordinary temperature. 5
Jacobsen, on reinvestigation, found that his preparation crystal-
lized after repeated cooling or on the addition of a small crystal. 6
It forms white needles, melting at 26. It dissolves slightly
in water, yielding a solution which is coloured blue by ferric
chloride ; the alcoholic solution, on the other hand, is coloured
a splendid dark green, which passes into blue when water is
added.

a-Metaxylenyl methyl ether, C 6 H 3 (CH 3 ) 2 OCH 3 , is a liquid
which has a faint smell resembling that of benzene, and boils
at 192.



Ber. Dcutsch. Chem. Ges. xi. 23.

Thbl, ibid, xviii. 359, 2561 ; Nblting and Forel, ibid, xviii. 2663.

Smith, Coutts and Brothers, Journ. Chem. Soc. 1886, i. 17.

Jacobseu, Bcr. Deutsch. Chem. Ges. xvii. 161.

Ber. Deutsch. Chem. Gas. xviii. 2921.

Ibid, xviii. 3463.






PARAXYLENOL. 401



a-Mctaxylenyl acetate, C 6 H 8 (CH S ) 8 O.CO.CH S , is a liquid
boiling at 226, which has a faint odour of oil of bergamot.

Melting-point.
a-Bromometaxylenol, C 8 H 8 Br.OH, oily liquid ...

a-Dibromometaxylenol, C 8 H 7 Br 2 .OH, fine, colourless ) ^^o
needles f i6

a-Tribromometaxylenol, C 8 H 6 Br 3 .OH, long, colourless ) , 70< ,
needles f '

v-Mctaxylenol (1:3:2) crystallizes in silky plates or long,
flat needles, melts at 74 - 5, boils at 211 212, and gives no
colouration with ferric chloride.

v-Tribromometaxylenol crystallizes from hot alcohol in long,
light yellow needles, melting at 175.

s-Metaxylenol (1:3:5) is deposited from solution in hot
water or from sublimation in splendid white needles, melting
at 68. It boils at 219'5, and gives no colouration with ferric
chloride.

s-Tribromometaxyknol crystallizes from alcohol or benzene in
fine, white needles, melting at 166.

Paraxylenol (1:4:2) has been prepared from paraxylidine ; x
it melts at Y4'5, sublimes in needles at a slightly higher
temperature, boils at 21 1*5 and crystallizes from hot water or
very dilute alcohol in large, flat needles. It gives no colouration
with ferric chloride. The solid compound prepared by Wurtz
was almost pure paraxylenol.

Melting-point.

Monobromoparaxylenol, C 8 H 8 Br.OH, colourless, flex- ) gyo
ible needles )

Tribromoparaxylenol, C 8 H c Br 3 .OH, deep golden | -^o
yellow needles j

The great similarity existing between para- and v-meta-
xylenol is somewhat remarkable (Jacobsen).

A xylenol occurs in crude creosote, which boils at 220, does
not crystallize, and on heating with potash and methyl iodide
yields a methyl ether, boiling at 200. 2 This substance is pro-
bably a mixture, and, from its high boiling-point, would seem to
consist chiefly of a-orthoxylenol. 3

1 Nolting, Witt and Forel, Bar. Dcutech. Cliem. Gcs. xviii. 2664.
- Mavassc, Ann. Chem. Pharm. clii. 75 ; Tiemann and Mendelsohn, Her
Deutsch. Chcm. Gcs. x. 57.
8 Nolting, Witt and Forel, ibid, xviii. 2664.
VOL. III. PART IV. ]l J)



402 AROMATIC COMPOUNDS.

Robiquet, by the distillation of aloes with lime, obtained a
liquid which he called alo'isol. This substance has been shown
by Rembold to be a mixture, the portion soluble in alkalis having
the composition of a xylenol. 1



DIHYDROXY-XYLENES, C 6 H 2 (CH 3 ) 2 (OH) 2 .

2214 Homortinol, or Paraxylorcinol (1 :4 :2:6), was obtained
by Stenhouse from Usnca larbota and Cladonia rangifcrina
and named by him /3-orcin, 2 a name which was subsequently
changed by him and Groves into beta-orcinol. It is a decom-
position product of the barbatic acid, C 19 H ?0 O 7 , which occurs in
these lichens. 3 Lamparter has succeeded in obtaining it, together
with orcinol, from liccella fuciformis*

Its constitution was determined by Kostanecki, who prepared
it from a-nitroparaxylidine, by first converting it into nitroxylenol,
reducing this to amidoxylenol, and finally passing from this to
paraxylorcinol by means of the diazo-reaction. 5

It is less soluble in water than orcinol, and is deposited in
quadratic crystals, melting at 163. It possesses a slightly sweet
taste, boils at 277 280, and is coloured red by ammonia in
presence of air more rapidly than orcinol. Its aqueous solution
gives with ferric chloride a light carmine-red colouration, quite
distinct from the purple-red produced with orcinol. Like the
latter it yields a red solution with a beautiful green fluorescence
when heated with chloroform and caustic soda (Kostanecki).

Nitroso2-)araxylorcinol C 6 H(CH 3 ) 2 (OH)0(NOH), is formed by
the action of nitrosyl sulphate (Part III. p. 295) on an aqueous
solution of paraxylorcinol, as a lustrous, orange-red precipitate,
which crystallizes from glacial acetic acid in small, lustrous, red
prisms.

Metaxylorcinol (1:3:4:6) is obtained from s-nitro-a-meta-
xylidine. It is readily soluble in water, has an acid taste, melts
at 125 and boils at 276 279. It crystallizes from chloroform
in brilliant white, monosymmetric plates, which can also be
obtained by sublimation. No red colouration is produced by
exposure to ammonia and air. 6

1 Ann. Chcm. Pharm. cxxxviii. 186. " Phil. Trans. 1848, 63.

3 Ibid, cciii. 285. * Ibid, cxxxiv. 243.

5 Bcr. Dcutsch. Chcm. Gcs. xix. 2318.

6 Pfaff, ibid. xvi. 611 and 1135 ; Kostauecki, loc. cit.



TRIHYDROXY-XYLENES. 403

Gundelach, by heating chlorometaxylenesulphouic acid to
230 250 with caustic potash, obtained a dihydroxy-xylene
which should be identical with metaxylorcinol, since, according
to Jacobsen, the side chains of the sulphonic acid have the
following arrangement : CH 3 : CH 3 : Cl : SO 3 H=1 : 3 : 4 : 6. 1 It
crystallizes in microscopic prisms, which are tolerably soluble in
water, melt at 120 and are coloured deep red by ammoniacal
air. 2 This compound is probably impure metaxylorcinol.

The following dihydroxy-xylenes have been prepared by the
reduction of the xyloquinones:

Paraxyloquinol, or Hydrophloronc (1 : 4 : 2 : 5), is readily soluble
in alcohol, slightly in boiling water and benzene, and crystallizes
in nacreous plates or tablets, which melt at 210 and sublime in
long needles. It reduces silver solution and is re-oxidized to the
quinone by ferric chloride. The diethyl ether, C 8 H 8 (OC 2 H 5 ) 2 , is
formed by heating it with ethyl bromide and caustic potash; it
forms lustrous plates, which melt at 105 106, and have an
odour resembling that of peppermint (Stadel and IIolz).

Mctaxyloyuinol (1:3:2:5) sublimes in needles and melts at
149.

Ortlwxyloquinol (1:2:3:6) crystallizes from water in crusts,
which melt at 221 with decomposition.



TRIHYDROXY-XYLENES.

2215 Trihydroxymetaxylene, C 6 H(CH 3 ) 2 (OH) 3 , is formed by the
reduction of hydroxymetaxyloquinone (p. 404) with sulphurous
acid. It is tolerably soluble in cold, readily in hot water, and
crystallizes in colourless or yellowish transparent tablets, con-
taining a molecule of water, which is lost at 80, the anhydrous
compound melting at 121 122. It is reduced to metaxylenc
when heated with zinc-dust. Oxidizing agents readily convert
it into the quinone ; if the aqueous solution be merely allowed
to evaporate in the air, the quinhydrone crystallizes out in long
needles resembling those of potassium permanganate.

Triacdoxymdaxykne, C 6 H(CH 3 ) 2 (O.CO.CH 3 ) 3 , is obtained by
the action of acetyl chloride, and crystallizes from alcohol in
colourless, lustrous prisms, which melt at 99, and sublime
without decomposition when carefully heated.

1 Her. Dcutsch. Chcm. Gcs. xviii. 1762. " Bull Soc. Chim. xxviii. 34a

D D 2



404 AROMATIC COMPOUNDS.



THE XYLOQUINONES, C 6 H 2 (CH 3 ) 2 O 2 .

2216 Paraxyloquinone (1:4:2: 5). Rommier and Bouilhon,
by oxidizing the fraction of crude cresol boiling between 195
220 with sulphuric acid and manganese dioxide, obtained two
isomeric quinones, C 8 H 8 O 2 , and gave to the one, which is formed
in larger quantity and melts at 60 62, the name of phlorone,
and to the other, melting at 125, that of metaphlorone. 1 Accord-
ing to Gorup-Besanez and v. Rad, phlorone is also formed by the
oxidation of wood-tar creosote. 2 Nietzki then obtained para-
xyloquinone by the oxidation of crude xylidinc and of paradi-
amidoxylene with potassium dichromate and sulphuric acid, and
found that its properties agree with those of metaphlorone ; 3
Carstanjen then showed that phlorone is a mixture of toluquinone
with paraxyloquinone, and that the latter yields paraxylene on
heating with zinc-dust. 4 It is best prepared from paraxylidine
in the same way as benzoquinone from aniline. 5

Paraxyloquinone is only slightly soluble in water and cold
alcohol ; it crystallizes from hot alcohol in splendid golden-
yellow needles, which melt at 123'5 and readily sublime.

Orthoxi/loquinone (1:2:3:6) has been prepared from v-ortho-
xylidine by oxidation ; it is slightly soluble in water, more
readily in alcohol, and sublimes in yellow needles, which melt
at 55.

Metaxyloquinone (1:3:2: 5) is formed by the oxidation of
v- and s-metaxylidine, and crystallizes in splendid yellow needles,
melting at 73.

Hydroxymetaxyloquinone, C 6 H(CH 3 ) 2 (OH)O 2 , is fanned when
diamidomesitylene, C H(CH 3 ) 3 (NH : ) 2 , is distilled with potassium
dichromate and dilute sulphuric acid. It crystallizes from hot
water or ether in orange-red needles, has a characteristic smell
resembling that of benzoquinone, melts at 103, and sublimes
very readily in splendid, lustrous, deep golden-yellow needles.
Its aqueous solution is instantly coloured a splendid reddish
violet by the addition of any alkaline substance, and this
reaction is so delicate that the slightest traces of the quinone

1 Compt. Rend. Iv. 214.

2 Zeitschr. Ghent. [2] iv. 560 ; Ann. Chem. Pharm. cli. 158.

3 Bcr. Dcutsch. Chcm. Gcs. xiii. 470.

4 Journ. Prakt. Chcm. [2] xxiii. 421.

5 Noltingand Forol, Bcr. Deutsch. Chem. Gcs. xviii. 2563.



AM1DOXYLENES. 405



can be detected by it. Insoluble carbonates also produce this
colouration ; thus, if a 01 per cent, solution of the quinone be
shaken up with calcium carbonate, the colouration produced is
so deep that even a thin layer of the liquid appears quite
opaque. The presence of calcium carbonate can thus be shown
in very small quantities of mineral waters ; free carbonic acid
does not affect the colouration, so that the quinone forms a
valuable indicator for alkalimetry.

It forms salts, which readily decompose on warming or on
exposure to the air in presence of an excess of the base. The
potassium salt, C 8 H 7 (OK)0 2 , crystallizes from hot alcohol in
small, black needles, 1 mgrm. of which is sufficient to impart a
deep red colour to a litre of water. 1



AMIDO-DERIVATIVES OF THE XYLENES.

THE AMIDOXYLENES, OR XYLIDINES, C H 3 (CH 3 ) 2 NH 2 .

2217 Cahours gave the name of xylidine to the homologue of
toluidine and aniline which he obtained from his xylene (p. 386),
by nitrating it and submitting the nitroxylene formed to reduc-
tion. This substance and the xylidine obtained by Church in
the same manner was obviously a mixture of toluidines and
xylidines, while that prepared by Deumelandt from xylene
boiling at 140 consisted chiefly of a-metaxylidine, as was also
the case with that prepared by Hofmann and Martius by heating
paratoluidine hydrochloride to 300 with methyl alcohol. It
only became possible to obtain the six xylidines after the three
xylenes had been obtained in the pure condition and the six
nitroxylenes prepared from these. A mixture of them is manu-
factured on the large scale from tar-xylene, and the purity and
composition of commercial xylidine is therefore dependent on
that of the latter. Specimens now come into the market
containing as much as 25 per cent, of paraxylidine in addition
to ordinary metaxylidine. 2

The commercial product is employed in the manufacture of
azo-colours and of the cumidines, C 6 H 2 (CH 3 ) 3 NH 2 , which are
obtained by heating the hydrochlorides with wood-spirit.

1 Fittig and Sienermann, Ann. Chcm. Pluinn. clxxx. 27.

- Nolting, Witt and Forel, Bcr. Deutsch. Chem. Gcs. xviii. 2664 ; Stadel and

Hiilz, ibid, xviii. 2919.



406 AROMATIC COMPOUNDS.

v-Orthoxylidine (1:2: 3) is formed when solid dibromortho-
xylene is nitrated, the nitrodibromorthoxylene reduced to dibromo-
xylidine, and the bromine removed by treatment with sodium
amalgam and water. 1 It is a liquid which boils at 223; its
hydrochloride is tolerably soluble in water, and crystallizes in
white needles, containing a molecule of water. The sulphate is
only slightly soluble.

v-Acetorthoxylide, C 6 H 3 (CH 3 ) 2 NH(CO.CH 3 ), crystallizes from
hot benzene in white needles, melting at 134 . 2

a-Orthoxylidine (1:2:4) melts at 49 and boils at 226. It
is tolerably soluble in hot water, readily in alcohol, and crystal-
lizes when caused to solidify quickly or when rapidly deposited
from solution, in transparent, vitreous tablets, while it may be
obtained by the gradual evaporation of its petroleum-ether
solution in thick, monoclinic crystals. Its aqueous solution is
not coloured by bleaching powder; the solutions of its salts
colour pine-wood an intense yellow.

The hydrochloride is readily soluble in water, but only
slightly in hydrochloric acid, and crystallizes with one molecule
of water in long, very thin prisms.

a-Acetorthoxylide crystallizes from hot water containing a little
alcohol in long, thin, vitreous prisms, which melt at 99.

The base is converted by the diazo-reaction into a-ortho-
xylenol. 3

v-Mdaxylidine (1:3:2) was first obtained by Schmitz by
heating /3-amidomesitylenic acid, C 6 H 2 (CH 3 ) 2 (NH 2 )OO 2 H, with
lime. 4 Grevingk, 5 and Nolting and Forel, 6 then prepared it from
v-nitrometaxylene. It is a liquid boiling at 214.

Its hydrochloride crystallizes in thin, anhydrous, monoclinic
plates, which are readily soluble in water.

v-Acetmetaxylide crystallizes from benzene in white needles,
which melt at 176 '8. It is not attacked by caustic potash
solution, sulphuric acid, or hydrochloric acid, on heating in an
open vessel, but is decomposed by the last of these at 150.

a-Metaxylidine (1:3:4) has been known for a longer period
than any of its isomerides and is therefore also called ordinary
metaxylidine. It is formed by the distillation of a-amidomesity-
lenic acid with lime (Schmitz) and by the reduction of a-nitro-

1 Thbl, Ber. Deutsch. Chem. Ges. xviii. 2561 ; Wroblewsky, ibid, xviii. 2904,
xix. 235 ; Jacobsen, ibid, xviii. 3166.

2 Nolting and Forel, ibid, xviii. 2668. 3 Jacobsen, ibid. xvii. 159.

4 Ann. Chcm. Pharm. cxciii. 377. 5 Ber. Deutsch. Chem. Ges. xvii. 2422.

a Ibid, xviii. 2676.



XYLIDINES. 407



metaxylene. 1 It may also be readily obtained from commercial
xylidine by converting this into the hydrochloride and purifying
by re-crystallization. In order to obtain it perfectly pure, the acet-
xylicle is prepared, purified by re-crystallization, and decomposed
with sulphuric acid. The other xylidine can also be easily
obtained pure in this way. It is a liquid boiling at 212.

The hydrochloride is only slightly soluble in cold water, and
crystallizes in anhydrous, rhombic tablets; the hydrobromide
crystallizes even better, form ing splendid prisms (Sta'del andHolz).

a-Acetmetaxylide crystallizes from benzene in white needles
melting at 129 ; impurities cause a considerable lowering of the
melting-point.

s-Mctaxylidinc (1:3:5) is obtained by the reduction of the
corresponding nitroxylene ; 2 it is a liquid boiling at 220. Its
hydrochloride and nitrate crystallize in large, anhydrous needles ;
4 - 66 parts of the latter dissolve in 100 parts of water at 13.

s-Acetmetaxylide crystallizes from alcohol in large, flat needles,
melting at 140'5.

Paraxylidine (1 : 4 : 2) may be prepared in the usual way by the
reduction of nitroparaxylene, 3 and also from commercial xylidine ;
the latter is run into fuming sulphuric acid containing sufficient
trioxide to convert the bases into sulphonic acids, the mixture
being well stirred and then heated on the water-bath. The
solution is allowed to cool and the solid mass pressed under water
to separate the metaxylidinesulphonic acid in the crystalline
state. The sodium salt of paraxylidinesulphonic acid is then
prepared from the mother-liquor by neutralizing it with lime,
filtering, removing the calcium with carbonate of soda, and
concentrating the filtrate. It separates in splendid, nacreous
plates, which are freed from any adhering traces of the readily
soluble salt of the metaxylidinesulphonic acid by washing with
a little cold water. Pure paraxylidine is then obtained by the
dry distillation of the salt. 4

It is a liquid boiling at 215; its hydrochloride and nitrate
crystallize in flat needles or large tablets, and the sulphate, which
is only slightly soluble, forms small plates.

Acetparaxylide crystallizes from hot water or toluene in long
lustrous needles, melting at 139.

1 Tawildarow, Zeitschr. Chem. 1870, 418'; Nolting and Forel, loc. cit.

2 Wroblewsky, Ann. Chem. Pharm. ccvii. 95 ; Thol, Bcr. Deutsch. Chcm. Oes.
xviii. 359 ; Nolting and Forel, loc. cit.

3 Schaumauu, Her. Dcutsch. Chcm. Gcs. xi. 1537 ; NBltfog and Forel. ibid.
xviii. 2680. 4 Netting, Witt and Forel, xviii. 2664.



408 AROMATIC COMPOUNDS.



NITROXYLIDINES, C 6 H 2 (CH 3 ) 2 (NH 2 ) 2 NO 2 .

2218 s-Nitro-a-mdaxylidine (1:3:4:6) is formed by the
reduction of s-dinitrometaxylene with ammonium sulphide, and
crystallizes from hot water or alcohol in orange-red needles,
while it separates on the gradual evaporation of its alcoholic
solution in thick, deep red crystals, which melt at 123 . 1

v-Nitro-a-inetaosylidine (1:3 : 4 : 2) has also been prepared from
v-dinitrometaxylene, and forms golden-yellow needles, which
melt at 78. 2

a-Nitro-a-metaxylidine (1:3:4:5). In order to prepare this
compound, a-acetmetaxylide is treated with concentrated nitric
acid in the cold, and the product decomposed by heating with
sulphuric acid, diluted with half its volume of water. It
crystallizes from alcohol in long, red needles, which melt at 76. 3

A small quantity of s-nitro-a-rnetaxylidine is formed at the
same time (Nolting and Forel).

a-Nitro-s-metaxylidine (1 : 3 : 5 : 4) is obtained by the nitration
of s-metaxylidine with a mixture of nitric and sulphuric acids ;
it crystallizes in yellow needles, which melt at 54, and readily
volatilize with steam (Nolting and Forel).

a-Nitroparaxylidine (1:4:2:6) has been prepared by the
reduction of a-dinitroparaxylene with ammonium sulphide, and
crystallizes from alcohol in long, golden-yellow needles, melting
at 96. 4

ft-Nitroparaxylidine has not yet been obtained, as the cor-
responding dinitroparaxylene is immediately reduced to the
diamine by ammonium sulphide.

ry-Nitroparaxylidine (1 : 4 : 2 : 5) is formed by the nitration of
paraxylidine with a mixture of sulphuric and nitric acids, and
forms brownish yellow, lustrous crystals, which are readily soluble
in alcohol and melt at 142 . 5

Dinitroparaxylidine, C 6 H(CH 3 ) 2 (N0 2 ) 2 NH 2 (5:2: 3), is ob-
tained by the long-continued heating of trinitroparaxylene with

1 Fittig, Ahrens and Mattheides, Ann. Chem. Pharm. cxlvii. 18.



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