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potassium permanganate, ammonia and oxalic acid being simul-
taneously formed. 4 It is volatile with steam and crystallizes from
ether in red prisms melting at 55. It is reduced to orthohydro-
azotoluene by the further action of sodium amalgam ; this forms
colourless crystals melting at 165, which decompose at a
higher temperature into orthotoluidine and ortho-azotoluene, and
are readily oxidized to the latter in the air.

1 E. Fischer, Ber. Drutsch. Chem. Ges. ix. 890.
- Lelme, ibid. xiii. 1546.

3 Petriow, Eeilstein's Orrf. Clicm. 976 ; Bcr. Dcutsch. Chem. Gcs. vi. 557.

4 Hoogewerffand van Dorp, ibid. xi. 1203.



76 AROMATIC COMPOUNDS.

Meta-azotoluene is most readily formed by treating metanitro-
toluene with zinc-dust and alcoholic potash. 1 It crystallizes from
weak alcohol in orange-coloured rhombic prisms melting at 55.
When it is heated with alcoholic ammonium sulphide, the liquid
mdahydrazotoluene is formed and rapidly re-oxidizes in the air.

Para-azotoluene may be best obtained by dissolving 1 part of
paranitrotoluene in 10 parts of alcohol and gradually adding 22
parts of 4 per cent, sodium amalgam together with a sufficient
quantity of acetic acid. 2 The oxidation of paratoluidine with
potassium permanganate affords a very poor yield of the azo-
compound, but better results may be obtained by oxidizing the
sulphate of the base with potassium ferricyanide (Barsilowsky).
It is also formed by the action of chromic acid on a solution of
paratoluidine in glacial acetic acid, 3 and by that of bleaching
powder on the base dissolved in chloroform.*

It is slightly soluble in alcohol, readily in ether and petroleum-
spirit, crystallizing from the latter in orange-yellow needles
which melt at 144. When it is heated to 100 with alcoholic
ammonia in a closed vessel, parahydrazotoluene is formed and
crystallizes in large needles or tablets which melt at 124 and
decompose into paratoluidine and parazotoluene when more
strongly heated. It rapidly becomes oxidized to the latter when
its alcoholic solution is exposed to the air (Melms).

Barsilowsky, by the oxidation of paratoluidine with potassium .
ferricyanide, obtained parazotoluene and an isomeric substance, 5
which Perkin also obtained by the action of potassium dichromate
on a solution of toluidine sulphate. 6 It forms red, hexagonal
crystals and is a weak base ; Perkin was only able to prepare its
platinichloride, from the composition of which he concluded that
the compound was a triparatolylenediamine, C 21 H 21 N 3 , while
Barsilowsky found that it is reduced by alcoholic ammonium
sulphide to a compound isomeric with hydrazotoluene, which
crystallizes in small colourless plates and readily oxidizes in the
air. It is a weak base and forms a veiy characteristic oxalate,
(C 14 H 1G N 2 ) 2 C 2 H 2 O 4 + H 2 O, which separates from dilute alcohol
m star-like aggregates, which are very similar to the seed
feathers of the dandelion.

Barsilowsky, Ann. Clicm. Pharm. ccvii. 114.
Helms, Ber. Dcutsch. Chem. Ges. iii. 549.
Perkin, Journ. Chem. Soc. 1880, i. 553.
Schmitt, Journ. Prakt. Chem. [2] xviii. 198.
Ann. Chem. Pharm. ccvii. 102.
Journ. Chem. Soc. 1880, i. 546.






AMIDO-AZOTOLUENES. 77



K linger and Pitschke have now found that the red substance
is an amido-azo-compound of the formula C^H^N^ 1 It is
decomposed into paratoluidine and paraleucotoluidine, C 21 H 25 N 3 ,
by energetic reduction with tin and hydrochloric acid. This
compound crystallizes in small colourless plates, and is readily
oxidized topararosotoluidine, C 21 H 23 N 3 , which forms small lustrous
red plates, and dissolves in water with an intense violet-red
colour. The red substance has, therefore, the following con-
stitution, C 21 H 17 (NH 2 ) 2 N = N.C 6 H 5 .CH 3 . These compounds
will be more fully described in the sequel.

Ortho-azoxytolueneyG-^^R^^O, is formed when orthonitrotoluene
is heated with a solution of sodium in methyl alcohol, and
crystallizes from warm petroleum-ether in yellow, monoclinic
needles melting at 59 60. It is not converted into the
isomeric hydroxyazotoluene, C 7 H 7 .N 2 .C 7 H 6 .OH, on heating
with concentrated sulphuric acid, but a large quantity of ortho-
toluidine is formed, the oxygen thus liberated producing the
oxidation of a portion of the ortho-azoxytoluene to a mixture of
amorphous acids.

Klinger and Pitschke consider that the conversion of azoxy-
benzene into hydroxyazobenzene (Pt. III. p. 355) is brought
about in a similar manner, and may be looked upon as " hy-
droxylation by direct oxidation." 2

Amido-azotoluenes, CH 3 .C 6 H 4 N = N.C 6 H 3 (CH 3 )NH 2 , are
formed by the action of nitrous acid on orthotoluidine and
metatoluidine, while paratoluidine, as already mentioned, is thus
converted into diazo-amidotoluene. Compounds belonging to
this group are also formed by the action of a diazoparatoluene
salt on orthotoluidine or metatoluidine, as well as on aniline,
etc. 3

Amidortlio-azotoluene is obtained by passing nitrogen trioxide
into orthotoluidine floating on a saturated solution of common salt,
The product is allowed to stand for some time, washed with
water to remove any orthocresol which has been formed, treated
with dilute caustic soda and finally boiled with dilute hydrochloric
acid, the hydrochloride thus obtained being then decomposed by
ammonia.

Amidortho-azotoluene is slightly soluble in water, readily in
alcohol, and crystallizes in lustrous, golden plates or tablets,

1 Per. Dcutsch. Chcm. Ges. xvii. 2439.

2 Ibid, xviii. 2551.

3 Nietzki, ibid. x. 662, 832, 1156.



78 AROMATIC COMPOUNDS.

melting at 100. The hydrochloride, C 14 H 15 N 3 .C1H, is only
slightly soluble in water, and crystallizes in long, thin tablets
with a silver lustre.

This compound is decomposed into orthotoluidine and para-
tolylenediamine by the action of hydrochloric acid and tin or zinc
dust, and has therefore the following constitution :



~CH 3 ~~CH 3

Amidometa-azotoluene crystallizes from alcohol in broad,
golden-yellow needles melting at 80. The hydrochloride forms
long, dark blue needles, which are only slightly soluble in hot
alcohol, and, like all the other salts of this class, is decomposed
by water. On reduction with tin and hydrochloric acid, para-
tolylenediamine is formed.

Ortho-amidopara-azotolucne forms yellow tablets melting at 127
128; its hydrochloride crystallizes in cinnabar-red needles,
which appear of a steel-blue colour when seen by reflected light.

Metamidoparazotoluene crystallizes from alcohol in large, yellow,
plates, melting at 127; the hydrochloride forms small, steel-blue
needles.

Para-amidopara-azotoluene. Tn order to prepare this compound,
the isomeric diazo-amidoparatoluene is heated for twelve hours to
65 with five times its weight of paratoluidine and one equiva-
lent of paratoluidine hydrochloride. It crystallizes from alcohol
or acetic ether, in orange-red lustrous needles melting at 118-5.
Its hydrochloride crystallizes in light yellow needles and forms
a green solution in water. It is converted into paratoluidine
ami orthotolylenediamine by reduction. 1

On treatment with fuming sulphuric acid, a mixture of di-
sulphonic acids is formed, which comes into the market as
" Acid yellow R," since it dyes a redder shade than the colouring
matter obtained from amido-azobenzene (Part III. p 366),
which is therefore called " Acid yellow G."

a-Azoxytoluidine, C U H 12 N 2 (NH 2 ) 2 O, is formed by the action
of sodium amalgam on a solution of orthonitroparatoluidine in
absolute alcohol, and crystallizes from hot water in small, yellow
needles melting at 148. It is a diacid base, and on further
reduction yields the following compounds :

1 Nolting and Witt, Ber. Dcutseh. Chem. Ges. xvii. 77.



AZOXYTOLUIDINES.



a-Azotoluidinc, or Symmetric a-diamido-azotoluene, C 14 H 19 N 2
(NH 2 ) g , crystallizes from hot water in red needles which are
readily soluble in alcohol and melt at 159.

a-Hydrazotoluidine, C M H 18 (N 2 H 2 )(NH 2 ) 2 , is almost insoluble
in cold water and alcohol, but is slightly soluble in hot alcohol ;
it forms small, colourless, rhombic tablets which melt at 180.
It is tolerably stable in contact with cold water and alcohol,
but rapidly oxidizes when heated with them in the air. 1

ft-Azoxytoluidine, C U H 12 N 2 (NH 2 ) 2 O, is obtained from para-
nitro-orthotoluidine and crystallizes in long, yellow to yellowish
red, silky needles melting at 168; its salts crystallize well.
When heated with concentrated sulphuric acid, it is converted
into the isomeric hydroxyazo-compound, just as is the case with
azoxybenzene (Part III. p. 355) :



N.C 7 H 6 .NH 2 NC 7 H 5 (OH)NH 2

N.C 7 H 6 .NH 2 NC 7 H 6 .NH 2 .



This compound crystallizes from alcohol in. small, dark red
needles, which melt at 212 with decomposition. Its hydro-
chloride and sulphate are only slightly soluble in water. On
treatment with stannous chloride and hydrochloric acid, it
is resolved into ordinary diamidotoluene and diamidocresol,
C 6 H 2 (CH 3 )(NH 2 ) 2 OH, the hydrochloride of which crystallizes in
white needles which become coloured blue in the air ; the free
base immediately becomes resinous.

fi-Azotoluidine, or Symmetric /3-diamido-azotolucne, C 14 H 12 N 2
(NH 2 ) 2 , crystallizes from hot water in small, yellow needles, and
is deposited on the gradual evaporation of its alcoholic solution
in long, red needles, which melt at 197, and are slightly soluble
in water, readily in alcohol. The sulphate is only slightly
soluble in water, the hydrochloride being somewhat more readily
dissolved.

/3-fIydrazotoluidinc, C 14 H 12 (N 2 H 2 )(NH 2 ) 2 , forms yellow needles
which rapidly oxidize when exposed to the air in a moist state.
It decomposes without melting when heated, and burns with a
brilliant flame. It is almost insoluble in absolute alcohol, but
dissolves readily in dilute alcohol and water. 2

1 Bucknoy, Her. Deutsch. Chcm. GM. xi. 1451.

- Limpricht, Bcr. Deutsch. Cfiem. Ges. xviii. 1403 ; Graff, Ann. Chcm. Pharm.
ccxxix. 340.



80



AROMATIC COMPOUNDS.



The constitutions of the two azotoluidines are expressed by
the following formulae :



NIL.



NIL



NH. 2

CH/



NIL



>CH 3 .



~CH 3 CH 3



Metanitroparatoluidine is immediately converted by sodium
amalgam into the corresponding diamidotoluene, while metanitro-
ortho- and a-orthonitrometa-toluidine yield resinous products on
oxidation (Limpricht).

Asymmetric diamido-azotoluene, C 7 H 7 N NC 7 H 5 (NH 2 ) 2 , cor-
responds to chryso'idine (Part III. p. 301) and is formed by the
action of diazotoluene nitrate on a-diamidotoluene. It crystal-
lizes from alcohol in orange-yellow needles melting at 183. Its
hydrochloride, (C 14 H 16 N 4 )C1H, forms red needles. 1

2057 Tolusafranine, C 21 H 20 N 4 . The history of this dye, which
is simply known as " safranine " in commerce, has already been
briefly indicated. Phenosafranine chloride, the lower homologue
of tolusafranine, has been proved 2 to have the following con-
stitution :



NH,




N Cl



NIL



This formula explains all the facts which have been already
given (Part III. p. 369) concerning this substance, and also its
formation from one molecule of paradiamidobenzene and two
molecules of aniline.

Hofmann and Geyger were the first to subject the com-
mercial product to a searching examination ; they ascertained

1 Hofmann, Ann. Chem. Pharm. x. 218.
Witt, Ber. Deutsch. Chem. Gcs. xix. 3121. Nietzki, ibid. 3163.



TOLUSAFRANINE. 81



that it is a hydrochloride of the formula C 21 H 21 N 4 C1, which
is not attacked by alkalis, but is readily decomposed by moist
silver oxide, and that it is not a derivative of aniline, as had
been up to that time assumed, but of orthotoluidine, from which
it can be obtained by the action of nitrous acid and oxidation
of the products with arsenic or chromic acids. 1 Witt then
found that it is formed by heating amido-ortho-azotoluene with
orthotoluidine hydrochloride, 2 and by the oxidation of a mixture
of orthotoluidine and paratoluylenediamine. 3 In order to prepare
it, a solution of equal molecules of orthotoluidine and hydrochloric
acid is treated with the calculated quantity of sodium nitrite, to
obtain amido-ortho-azotoluene ; the product, after the addition of
some orthotoluidine hydrochloride, is allowed to stand and is
then reduced with zinc-dust and hydrochloric acid, a mixture of
y-diamidotoluene and orthotoluidine being formed, which is then
neutralized and oxidized with potassium dichromate; if the
solution were kept acid, toluquinone would be formed. 4 The
safranine is then precipitated with common salt, filtered off,
pressed, dried and brought into the market. 5

Tolusafranine hydrochloride, C 21 H 21 N 4 C1, is -tolerably soluble
in water and alcohol, forming red solutions which possess a
characteristic fluorescence ; the salt is precipitated from its
aqueous solution by the addition of hydrochloric acid in red
crystals, which are best obtained by crystallizing the commercial
product from boiling, dilute alcohol. The free base, obtained
from this compound by means of silver oxide, probably has the
formula C 21 H 21 N 4 OH, and forms reddish brown crystals which
take a faint green metallic lustre on drying, but have not yet
been obtained free from silver chloride ; they are soluble in
water and alcohol, but not in ether.

Tolusafranine nitrate, C 21 H t>1 N 4 .NO 3 , crystallizes in reddish
brown needles which are only very slightly soluble in cold
water.

Tolusafranine picrate, C 21 H 20 N 4 .C 6 H 3 (NO 2 ) 3 O, is obtained by
the addition of picric acid to a solution of one of the salts of
the base, and forms brownish red needles, insoluble in water,
alcohol and ether.



1 Ber. Deutsch. Chtm. Ges. v. 526.

2 Ibid. x. 874.

3 Ibid. xii. 939 ; Bindscbedler, ibid. xiii. 207.

4 Nblting, Schultz, Steinkohlentheer, 1049.

5 Ibid. 527.
VOL. III. PART IV.



82 AROMATIC COMPOUNDS.

Tolusafranine shows all the characteristic reactions of the
safranine?;

It is employed as a substitute for saffron for dyeing silk and
cotton mordanted with tannin.

2058 Toluylene-blue, C 15 H 18 N 4 .HC1 + H 2 O, is formed when 36
grms. of nitrosodimethylaniline hydrochloride, and 24 grms. of
metatoluylenediamine, each dissolved in 500 c.cm. of water at
30, are mixed ; evolution of heat takes place and a deep green
colouration is produced. If the solution be now allowed to stand,
flat, lustrous brown prisms separate out, but gradually fall into a
fine crystalline powder. These readily form blue solutions in
water, alcohol and acetic acid ; traces of free mineral acids change
the colour into reddish brown, the original shade being restored
by alkalis. The base is precipitated by alkalis from its solution
as a resinous mass which takes a cupreous lustre in the air.

Toluylene-blue is converted by tin and hydrochloric acid into
the leuco-compound, C 15 H 20 N 4 HC1, which is a deliquescent
crystalline substance and is veryTeadily re-oxidized.

Toluylene-red, C 15 H 16 N 4 , is formed, together with the leuco-
compound, when toluylene-blue is boiled with water for 15-20
minutes. Stannous chloride precipitates the colouring matter
as a double tin salt in crystals, which are then decomposed by
an alkali.

Toluylene-red crystallizes in orange-red needles containing
four molecules of water, which they lose at 150 160. The
anhydrous base is blood-red and only slightly soluble in alcohol ;
it forms rose-red normal salts, which are stable and readily
soluble in water, while its acid salts are coloured blue and are
decomposed by water.

Toluylene-molet, C 14 H U N 4 , is formed by warming toluylene-
blue with metatoluylenediamine dissolved in dilute acetic acid
for twelve hours to 35 40, the leuco-base of the blue compound
being simultaneously formed :

3C 15 H 18 N 4 + 2C 7 H 10 N 2 = C 14 H 14 N 4 + 3C 15 H 20 N 4 .

Toluylene-violet forms red crystals with a green reflection
and is even less soluble than toluylene-red ; its solution is flesh-
coloured and shows a remarkable . orange-yellow fluorescence.'
Its slightly soluble normal salts are 'coloured violet and crystal-
lize well, while the acid salts have a grass-green colour.



TOLUYLENE COLOURS. 83

Witt gives the following constitutional formulae for these
compounds : x

Toluylene-blue. Toluylene-red. Toluylene-violet.

,N(CH S ), xNfCHJ,



NN
> Jl >'

C 6 H 3 ^-NH 9 G" /J

\NH:



PHOSPHORUS DERIVATIVES OF TOLUENE.

2059 Paratolylphosphorus dichloride, CH 3 .C 6 H 4 PC1 2 , is obtained
by the continued heating of 15 parts of toluene with 200 parts
of phosphorus trichloride and 3 parts of aluminium chloride,
or by heating mercury paratolyl with phosphorus trichloride to
180 190 . 2 It is a crystalline mass, which fumes slightly in
the air, melts at 25, and boils at 245.

Paratolylphosphorus tetrachloride, CH 3 .C 6 H 4 PC1 4 , is formed by
the combination of the compound just described with chlorine,
and crystallizes from benzene in pointed prisms melting at 42.
When heated in a sealed tube to 200, it decomposes with
formation of the dichloride and parachlorobenzyl chloride :

2CH 3 .C 6 H 4 PC1 4 = CHj-C^PCa, + CH 2 C1.C 6 H 4 C1 + PC1 3 + HC1.

It rapidly deliquesces in the air, forming paratolylphosphorus
oxychloride, CH 3 .C 6 H 4 POC1 2 , which is, however, best obtained
in a similar manner to phenylphosphorus oxychloride, by the
action of sulphur dioxide on the tetrachloride. It is a thick
liquid, boiling at 284 285.

Paratolyl phosphenylous acid, CH 3 .C 6 H 4 P0 2 H 2 , is formed by
the action of water on the dichloride. It is slightly soluble
in water and crystallizes from alcohol in tablets melting at
104 105.

Paratolylphosphenilic acid, CH 3 .C 6 H 4 PO(OH) 2 , is obtained by
decomposing the tetrachloride or the oxychloride with water. It
is readily soluble in alcohol and crystallizes from water in matted,
woolly needles which melt at 181. It is decomposed by ignition

1 Bcr. Dcutsch. Chem. Gcs. xii. 931.

2 Michaelis and Paneck, Ann. Chem. Pharm. ccxii. 203.

G 2



84 AROMATIC COMPOUNDS.

with lime, with formation of toluene and calcium phosphate.
Potassium permanganate oxidizes it to parabenzophosphenilic acid,
C0 2 H.C 6 H 4 PO(OH) 2 , which will be described under benzoic acid.

Paratolylphosphine, CH 3 .C 6 H 4 .PH 2 , is obtained by heating
tolylphosphenylous acid in an atmosphere of carbon dioxide. It
is a liquid which possesses a most intense smell, inhalation of its
vapour producing headache and bleeding of the nose. It boils
at 178 and solidities at a lower temperature to a crystalline mass
which melts at 4. It is rapidly oxidized to tolylphosphenylous
acid in the air. It combines with hydriodic acid to form
paratolylphosphonium iodide, CH 3 .C 6 H 4 .PH 3 I, crystallizing in
broad, lustrous needles which deliquesce in the air and sublime
in cubes when heated to 340 in a current of carbon dioxide.

Dimethylparatolyl phosphine, CH 3 .C 6 H 4 .P(CH 3 ) 2 , is obtained
by the action of zinc methyl on the dichloride, and is a liquid
which has an unpleasant smell, boils at 210, dissolves in acids
and is not oxidized by exposure to the air. Mercuric oxide con-
verts it into dimethyltolylphosphine oxide, CHg.CgH^P^H^O,
which is a thick liquid. The phosphine combines with methyl
iodide to form CH 3 .C 6 H 4 P(CH 3 )I, crystallizing in needles which
melt at 225 and yield a strongly alkaline, deliquescent
hydroxide. 1 The corresponding chloride is a very hygroscopic
crystalline body. 2

Orthotolylphosphorus dichloride, CH 3 .C 6 H 4 PC1 2 , is obtained by
heating orthomercury tolyl with phosphorus trichloride. It is
a liquid which boils at 244 and does not solidify even at -20.
It combines with chlorine forming the tetrachloride as a solid
yellow mass. It is decomposed by water with formation of
orthotolylphosphenylous acid, which is a liquid but forms crystal-
line salts, while the orthotolylphosphenilic acid obtained from the
tetrachloride consists of small crystalline grains which melt at
141 (Michaelis and Paneck).

ARSENIC DERIVATIVES OF TOLUENE.

2060 Arsenparatolyl chloride, CH 3 .C 6 H 4 AsCl 2 , is obtained by
heating mercury paratolyl with arsenic trichloride. 3 It crystal-
lizes in tablets, melts at 31, and boils in an atmosphere of carbon
dioxide at 267 without Jocomposition. It combines with chlorine

1 Czimatis, Ber. Deutsch. Chem. Ges. xv. 2014.

2 Ibid. 2018.

3 Michaelis and La Coste, Ann. Chem. Pkarm. cci. 246.



ARSENIC DERIVATIVES OF TOLUENE. 85



forming the tetrachloride, a yellow crystalline mass, which is
semi-fluid at the ordinary temperature but solidifies completely
on cooling. It is converted by water into tolylarsenic acid,
CH 3 .C 6 H 4 AsO(OH) 2 , which crystallizes in long, thin needles.
When the dichloride is boiled with caustic soda solution, arsen-
tolyl oxide, CH 3 .C 6 H 4 AsO, is formed as a powder melting at
156.

Arsendiparatolyl chloride, (CH 3 .C 6 H 4 ) 2 AsCl, is formed when
mercury tolyl is boiled for a long time with three or four times its
amount of arsentolyl chloride. 1 It is an oily, yellow liquid which
is converted by boiling alcoholic potash into arsenditolyl oxide
[(CH 3 .C 6 H 4 ) 2 As] 2 O, which crystallizes from ether in silky needles
melting at 98. The monochloride combines with chlorine to
form arsendiparatolyl trichloride (CH 3 .C 6 H 4 ) 2 AsCl 3 , a yellow
powder ; this is immediately converted by water into dipara-
tolylarsenic acid, (C 7 H 7 ) 2 AsO(OH), a white crystalline mass
which is slightly soluble in water, readily in alcohol, and crystal-
lizes from the latter in granules melting at 167. It is oxidized
by an alkaline solution of potassium permanganate to dibenzo-
arsenic acid, (C0 2 H.C 6 H 4 ) 2 As0 2 H.

Triparatolylarsine, (CH 3 .C 6 H 4 ) 3 As, is formed by heating
arsenparatolyl oxide to 360 :

3CH 3 .C 6 H 4 AsO = (CH 3 .C 6 H 4 ) 3 As+ As 2 O 3 .

It separates from ethereal solution in large crystals which
melt at 145 and only volatilize at temperatures above 360.
When chlorine is passed into its chloroform solution, arsentri-
tolyl dichloride, (CH 3 .C 6 H 4 ) 2 AsCl 2 , is formed as a white crystal-
line mass which is dissolved almost without decomposition by
boiling water.

Tritolylarsine is oxidized by alkaline potassium permanganate
solution to tribenzo-arsenic acid, (CO 2 H.C 6 H 4 ) 3 As(OH) 2 , which
.vill be described under benzoic acid.

Arsenorthotolyl chloride, C 6 H 3 .C 6 H 4 AsCl 2 , has been obtained
from mercury orthotolyl and arsenic trichloride, and is a faintly
smelling liquid which boils at 264 265 in an atmosphere of
carbon dioxide without undergoing decomposition. It combines
with chlorine to form the tetrachloride, which is a thick honey-
yellow liquid. When the dichloride is boiled with soda solution,
arsenorthotolyl oxide, CH 3 C 6 H 4 AsO, is formed as a powder which

1 La Posto, ibid, ccviii. 18.



AROMATIC COMPOUNDS.



is readily soluble in hot water, slightly in alkalis, and melts
at 145 146.

Orlhotolylarsenic acid,, CH 3 .C 6 H 4 As.O(OH) 2 , is obtained by the
action of water on the tetrachloride, and crystallizes from hot
water in fine needles, which melt at 159 160 and are con-
verted by prolonged heating into the crystalline anhydride,
arsenorthotolyl dioxide, CH 3 .C 6 H 4 As0 2 (La Coste and Michaelis).



ANTIMONY DERIVATIVES OF TOLUENE.

2061 These compounds are obtained by the action of sodium
on a mixture of antimony trichloride with bromotoluene
dissolved in benzene. 1

Paratolylstibine, Sb(C 6 H 4 .CH 3 ) 3 , is readily soluble in benzene,
slightly in alcohol, and crystallizes in large, transparent, lustrous
tablets melting at 127'5. It forms compounds with the
elements of the chlorine group, which crystallize from benzene
in lustrous prisms.

Melting-point.

Paratolylstibine chloride, Sb(C 7 H 7 ) 3 Cl 2 . . 156'5
Paratolylstibine bromide, Sb(C 7 H 7 ) 3 Br 2 . . 233'5
Paratolylstibine iodide, Sb(C 7 H 7 ) 3 I 2 . . 182'5

Paratolylstibine oxide, Sb(C 7 H 7 ) 3 O, is obtained by treating the
bromide with alcoholic potash and washing the residue with
water ; it is slightly soluble in benzene, from which it crystallizes
in small needles melting at 223'5. If it be dissolved in hot
glacial acetic acid and treated with sufficient water to produce
turbidity, fine, transparent crystals of paratolylstibine hydroxide,
Sb(C 7 H 7 ) 3 (OH) 2 , are deposited on cooling ; this compound melts
at 169-5.

Metatolyhtibine, Sb(C 6 H 4 .CH 3 ) 3 , forms large tablets melting at
64-5 ; the bromide, which melts at 113 and crystallizes well, is
much more readily soluble in ether than its isomerides.



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