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who heated the chloride to 100 with a solution of sodium in
absolute alcohol. It is a transparent, colourless liquid, which
smells like ethyl benzoate and boils at 220 -225.

Benzenyl triacetate, C 6 H 5 .C(OC 2 H 3 O) 3 , is formed by the action
of silver acetate on the chloride, and is a liquid which decom-
poses on distillation into acetic anhydride and benzoic an-
hydride. If it be allowed to stand in the air or over sulphuric
acid in a vacuum, white needles separate out, which melt at
70, and have the composition of acetobenzoic anhydride
(Limpricht).

Monochlorobenzenyl trichloride, C 6 H 4 C1.CC1 3 . The ortho-
compound has been obtained by the action of phosphorus penta-
chloride on salicylic acid, C 6 H 4 (OH)C0 2 H ; it is crystalline,
melts at 30 and boils at 260 . 2 The meta-compound has been
prepared in a similar manner from metasulphobenzoic acid,
C 6 H 4 (SO 3 H)CO 2 H, and boils at 235 ; 3 the para-compound is
formed by the chlorination of benzenyl trichloride in presence of
iodine ; it boils at 245 and yields parachlorobenzoic acid when
heated with water to 200 (Beilstein and Kuhlberg).

Dichlorobenzenyl trichloride, C 6 H 3 C1 2 .CC1 3 , has been prepared
by the action of chlorine on a boiling mixture of the dichloro-
toluenes obtained by chlorinating toluene. The product boils
at 278 280 and yields three dichlorobenzoic acids on heating
with water. 4

Trichlorolenzenyl trichloride, C 6 H 2 C1 3 .CC1 3 , is formed by pass-
ing chlorine into boiling trichlorotoluene ; it crystallizes from
alcohol in very fine needles, melts at 82 and boils at 307 308.
Tetrachlorolenzenyl trichloride, C 6 HC1 4 .CC1 3 , forms fine, short
needles, melts at 104 and boils at 316 . 5

1 Ince, Abst. Proe. Chem. Soc. 1885-6, 131.

2 Kolbe and Lautemann, Ann. Chem. Pharm. cxv. 195.

3 Carius and Kammerer, ibid, cxxxviii. 58.

4 Schulz, ibid, clxxxvii. 260 ; Aronheim and Dietrich, Bcr. Deutsch. Chem
Ges. viii. 1401.

8 Beilstein and Kuhlberg, Ann. Ckem. Pharm. cl. 286.



BENZONITRIL. 197



BENZONITRIL AND ITS DERIVATIVES.

2114 Benzonitril, C 6 H 5 .CN. This substance was prepared by
Liebig and Wohler by heating benzamide with baryta, 1 but was
not investigated by them, and its identity with the benzonitril
discovered by Fehling was established at a much later period.
The latter chemist obtained it by the dry distillation of ammo-
nium benzoate, 2 from which it is formed by loss of water.
It can be prepared by a similar reaction from benzamide,
C 6 H 5 .CO.NH 2 , by heating it with phosphorus pentoxide, 3 phos-
phorus pentachloride, 4 phosphorus pentasulphide, 5 benzoyl chlo-
ride, 6 potassium benzoate, 7 or caustic lime. 8

Among many other methods of preparation, some of which
have been already mentioned (Part III., p. 35), the following
are the most important. It can readily be obtained by distilling
two molecules of benzoic acid with one molecule of potassium
thiocyanate :

C 6 H 5 .C0 2 H + HSCN = C 6 H 5 .CN + CO 2 + H 2 S.

One half of the benzoic acid is converted into the potassium
salt, from which it can readily be recovered. 9

Lead thiocyanate may be substituted for the potassium salt : 10

2C 6 H 5 .C0 2 H + Pb(SCN) 2 = 2C 6 H 6 .CN + PbS + H 2 S + 2CO 2 .

Benzonitril is synthetically prepared by the distillation of
sodium benzenesulphonate with potassium cyanide, 11 as well as
by heating iodobenzene to 350 with silver cyanide, 12 or by the
action of cyanogen chloride on benzene in presence of aluminium
chloride. 13 It is obtained from aniline by converting the latter
into diazobenzene chloride and heating this with a solution of

Wbhler, Ann. Chem. Pharm. cxcii. 362. 2 Ibid. xlix. 91.

Hofmann and Buckton, ibid. c. 155.

Gerhardt, Chim Org. iv. 762 ; Henke, Ann. Chem. Pharm. cvi. 276.
Henry, Ber. Deutsch. Chem, Oes. ii. 307.
Sokolow, Gerhardt' s Org. Chim. i. 386.
Kekule, Ber. Deutsch. Chem. Qes. vi. 113.
Anschiitz and Schulz, Ann. Chem. Pharm. cxcvi. 48.
Letts, Ber. Deutsch. Chem. Qes. v. 673.
Kriiss, ibid. xvii. 1766.

Merz, Zeitschr. Chem. 1868, 33 ; Ber. Deutsch. Chem. Ges. iii. 710.
Merz and Weith, ibid. x. 746.
13 Friedel nd Crafts, Bull. Soc. Chim. xxix. 2.



198 AROMATIC COMPOUNDS.

the double cyanide of potassium and copper. 1 It can easily bo
prepared in the pure state by distilling benzamide with phos-
phorus pentoxide and rectifying the product over the latter. A
good yield is obtained by Letts's process, according to which the
mixture of benzoic acid and potassium thiocyanate is heated in
an apparatus connected with an inverted condenser until a
white, solid mass has been formed. The product is then dis-
tilled, the distillate freed from benzoic acid by means of ammonia,
and the benzonitril finally distilled in steam ; he thus obtains 80
per cent, of the theoretical yield. Merz, by the distillation of
500 grms. of sodium benzenesulphonate with 330 grins, of
potassium cyanide, obtained in one case 130 and in another 140
grms. of the crude 80 per cent, nitril, while Henry, employing
his own method, obtained half the theoretical yield.

Properties. Benzonitril is a mobile liquid, which smells like oil
of bitter almonds, has a sp. gr. of T023 at 0, boils at 191 and
solidifies in a mixture of ether and solid carbon dioxide to a crystal-
line mass, melting at 17. 2 It is miscible with alcohol and ether,
and dissolves in about 100 parts of water (Fehling). On boiling
with caustic potash it is converted into benzoic acid, and it is re-
duced in alcoholic solution by zinc and hydrochloric acid to benzyl-
amine (Mendius) ; fuming sulphuric acid in the cold polymerizes
it to cyanphenin, but on heating, forms metasulphobenzoic and
benzenedisulphonic acids (Hofmann and Buckton). When it
is mixed with benzene and concentrated sulphuric acid, dibenz-
imido-oxide, C 14 H 12 N 2 O, is obtained ; it crystallizes in thick vitre-
ous prisms and has basic properties. 3 On heating it with dilute
hydrochloric acid, dibenzamide is formed. 4 Both substances are
obtained when well-cooled, fuming sulphuric acid is allowed to
drop into benzonitril, and the mixture treated with water after
standing for some time. 5 Their formation is explained by the
following equations :

C e H 5 .CN C 6 H 5 .CO X

+ H 2 >NH

C 6 H 5 .CN C 6 H 5 .C4NH.

C 6 H 5 .CO X C 6 H 6 CO V

>NH + H 2 = >NH+NH 3 .

C 6 H 6 .C/NH C 6 H 5 CO/



Sandmeyer, Ber. Deutsch. C/iem. Ges. xvii. 2653.
Hofmann, Jahresber. 1862, 335.



8 Klein and Pinner, Ber. Deutsch. Chem. Ges. xi. 764.

4 Pinner, ibid. xvii. 2006.

8 Gumpert, Journ. Prakt. Chem. [2] xxx. 87 ; Pinner, ibid. xxx. 125.






BENZONITRIL. 199



When benzonitril is shaken up with a warm mixture of caustic
potash solution and hydrogen peroxide, it is rapidly converted
into beiizamide, pure oxygen being evolved : l

C 6 H 5 .CN + 2H 2 O 2 = C 6 H 5 .CO.NH 2 + H 2 + 2 .

If benzonitril be taken internally, it appears in the urine in
the form of oxybenzonitrilsulphuric acid, C 6 H 4 (O.S0 3 H)CN,
which readily decomposes into sulphuric acid and the nitrils of
salicylic acid and parahydroxybenzoic acid ; the meta-compound,
however, is not formed. 2

Benzonitril combines with hydrobromic acid to form the
crystalline compound, C 6 H 5 .CN + 2HBr, which is converted by
water into benzamide : 3

C 6 H 6 .CBr 2 .NH 2 + H 2 O = C 6 H 5 .CO.NH 2 + 2HBr.

According to Henry, a similar compound is formed with
hydriodic, 4 but not with hydrochloric acid ; when, however, a
current of the latter gas is passed into an ethereal solution of
platinum chloride and benzonitril, long needles separate out,
which decompose in dry air into their three components. 5

When benzonitril is heated with bromine, the monobromide,
(C 7 H 5 NBr) 2 , is formed ; it crystallizes from ether in small
needles, which partially sublime when heated and are partially
decomposed into bromine, benzonitril and cyaiiphenin ; while on
heating with lime, some carbon dioxide and ammonia are evolved
in addition to the compounds mentioned. A dibromide also
appears to exist, but it is very unstable. 6

It combines with some metallic chlorides to form the
Mowing solid compounds, C 7 H 5 N,AuCl 3 , (C 7 H 5 N) 2 PtCl 4 ,
(C 7 H 5 N) 2 SnCl 4 and (C 7 H 5 N) 2 TiCl 4 , the last of which forms
bright crystals which may be sublimed. 7

2115 Cyanphenin, C 21 H 15 N 3 . This compound, which corre-
sponds to cyanethin (Part I., p. 562), was obtained by Cloez
by heating benzoyl chloride with potassium cyanate, 8 and
Engler prepared it, as already mentioned, from benzonitril

Eadziszewski, Scr. DeutseJi. Chem. Gcs. xviii. 355.

Baumann, ibid. xvii. Rof. 256.

Engler, Ann. Chem. Pharm. cxlix. 307.

Sull. Soc. Cfiim. vii. 85.

Klein and Pinner, Ber. Dcutsch. Chem. Gcs. x. 1891.

Engler, Ann. Chem. Phwrm. cxxxiii. 144.

Henke, ibid. cvi. 284.

Ibid. cxv. 27.



200 AROMATIC COMPOUNDS.

bromide. Hofmann found that it is formed when benzonitril
is heated with sodium, 1 and Klein and Pinner when it is treated
with fuming sulphuric acid. 2 It is also obtained in tolerable
quantity, according to Henry, together with benzonitril, by the
action of phosphorus pentasulphide on benzamide, and, together
with an oily base, C 16 H 18 N 2 , the hydrochloride of which, C 16 H 19
N 2 C1, crystallizes in six-sided tablets, when benzonitril is heated
with zinc ethyl. 3

Cyanphenin is a hard, crystalline substance, which melts at
231, sublimes in needles, arid boils above 350. It is insoluble
in water, slightly soluble in alcohol and ether, more readily in
carbon disulphide and ethyl iodide. It is not attacked when
heated with aqueous or alcoholic potash, but is converted into
benzoic acid by heating to 220 4 with fuming hydriodic acid,
or to 250 with concentrated hydrochloric acid (Frankland and
Evans).



BENZIMIDO-ETHERS.

2116 The Benzimido-ethers include the compounds which are
formed by the action of hydrochloric acid on a mixture of
benzonitril with an alcohol. Of these compounds the isobutyl
ether has been more fully described ; 5 its formation is preceded
by that of a compound which forms large, lustrous crystals,
which fume in moist air and decompose into hydrochloric acid,
ammonium chloride and isobntyl benzoate :

/NH 3 C1
5 .C/ OC 4 H 9 +H 2 O =, HCi+NH 4 Cl+C 6 H 5 .CO.OC 4 H e .



If, however, the compound be freed from benzonitril and
isobutyl alcohol by washing with ether and allowed to stand
over caustic soda, a molecule of hydrochloric acid is given off
and the hydrochloride of benzimido-isobutyl ether remains

Ber. Dcutsch. Chem. Oes. i. 198.

Ibid. xi. 764 ; Pinner, Journ. Prakt. Chem. [2] xxx. 125.

Frankland and Evans, Journ. Chem. Soc. 1880, i. 563.

Engler, Ann. Chem. Pharm. cxlix. 310.

Pinner and Klein, Ber. Deutsch. Chem. Ges. x. 1889 ; xi. 4.



BENZIMIDO-ETHERS. 201

behind ; it decomposes on heating into benzamide and isobutyl
chloride :

^NH 2 C1

C 6 H 5 .C^ = C 6 H 6 .CO.NH 2 +C 4 H 9 C1.

X OC 4 H 9

It is decomposed by a solution of ammonia in absolute alcohol,
with formation of the free isobutyl ether, ammonium chloride
and benzenylamidine hydrochloride.

Benzimido-isobutyl ether, C 6 H 5 .C(NH)OC 4 H 9 , is a thick, oily
liquid, which partially decomposes on distillation ; it readily
recombines with hydrochloric acid ; cold, concentrated sulphuric
acid converts the hydrochloride into the acid sulphate, C 6 H 5 C
(OC 4 H 9 )NH 2 .SO 4 H, which crystallizes in long, pliant needles.

Benzimido-acetic ether, C 6 H 5 .C(NH)OC 2 H 3 O, is formed by
boiling the isobutyl ether with acetic anhydride ; it is insoluble
in water and acids, dissolves in alcohol and crystallizes in needles,
melting at 116.

Benzimido-ethyl ether, C 6 H 5 .C(NH)OC 2 H 5 . The hydrochloride
of this compound forms large, lustrous, transparent prisms,
which decompose at 118 120 with formation of benzamide.
In other respects the compound resembles its isobutyl analogue. 1

Benzimido-thio-ethyl ether, C 6 H 5 .C(NH)SC 2 H 5 . The hydro-
chloride of this compound is formed when hydrochloric acid is
passed into a mixture of ethyl mercaptan and benzonitril :

NH 2 C1
C 6 H 5 .CN4 HS.C 2 H 5 +HC1 = C 6 H 5 .Cf

\SC 2 H 5 .

It crystallizes in thick prisms, which melt at 188 and are
readily soluble in water and alcohol.

The hydriodide is obtained by heating thiobenzamide to 100
with ethyl iodide :

xNH 2 /X NH 9 I



It forms long, monosymmetric prisms, melting at 142. Alkalis
separate the ether from these salts as a strongly-smelling, oily
liquid, which is soluble in water and readily decomposes into
benzonitril and mercaptan. 2

1 Pinner, Ber. Deutsch. Chctn. Ccs. xvi. 1654.

2 Bernthsen, Ann. Chem Pharm. cxcvii. 348.



202 AROMATIC COMPOUNDS.

Bensimido-thwbenzyl ether, C 6 H 5 .C(NH)S.CH 2 .C 6 H 5 . The
hydrochloride is obtained by the action of benzyl chloride on
thiobenzamide, or of hydrochloric acid on a mixture of benzyl
hydrosulphidc and benzonitril. It is soluble in water and
alcohol, and crystallizes in white tablets melting at 181. The
free base is very unstable (Bernthsen).



BENZENYLAMIDINES.

2117 Benzenylamidine or Benzimido-amide, C 6 H V C(NH)NH 2 ,
is formed, as already mentioned, by the action of alcoholic
ammonia on the hydrochloride of benzimido-isobutyl ether :

/NH 2 C1 //NH 2 C1

C 6 H 5 .C<f + NH 3 = C 6 H 6 .Cr + HO.C 4 H 9 .

X OC 4 H 9



Free benzimido-isobutyl ether is simultaneously formed, but
the quantity of this product diminishes when the temperature
at which the reaction is carried out is raised. 1 The product is
evaporated in a vacuum, the residue washed with ether and
crystallized from alcohol, yielding benzenylamidine hydrochloride
in flat needles, which are decomposed by caustic potash but not
by ammonia ; by shaking out with ether and evaporating, the
free base is obtained as a crystalline mass, which is slightly
soluble in water, readily in alcohol and has an alkaline taste and
reaction. It decomposes spontaneously after some time with
evolution of ammonia, which is also given off on heating,
benzonitril and cyanphenin being formed.

If it be heated to 100 with ethyl iodide, the product
decomposed with caustic soda and extracted with ether, ethyl-
lenzenylamidine, C 6 H 5 C(NC 2 H 6 )NH 2 , is obtained as a strongly
alkaline, thick, oily liquid.

Dibenzenyltriamine, C 14 H 13 N 3 , is formed, together with acet-
amide, when benzenylamidine is boiled with acetic anhydride :



NH + NH.



1 Pinner and Klein, Bcr. Dcutsch. Chem. Gcs. x. 1889.






PHENYLBENZENYLAMIDINE. 203

It crystallizes in long, flat needles, which melt at 108 109
and are not decomposed even at 240 . 1

Phenylbenzenylamidine, C 6 H 5 .C(NH)N(C 6 H 5 )H, is obtained,
together with diphenylbenzenylamidine, by heating benzonitril
to 220 240 with aniline hydrochloride :

NH
C 6 H 5 .CN + N(C 6 H 5 )H 2 = C 6 H 5 .C^

\N(C 6 H 5 )H.

The product is extracted with cold water and the solution
precipitated with ammonia ; the base thus obtained is very readily
soluble in alcohol, and crystallizes badly in small crusts or warts
composed of plates, which melt at 111 112, and, on further
heating, partially sublime and are partially decomposed into
aniline and benzonitril.

Phenylbenzenylamidine hydrochloride is a syrup, miscible
with water and alcohol in all proportions. 2 It is converted by
the action of sodium amalgam on its alcoholic solution into
benzidenephenyldiamine, C 6 H 5 .CH(NH 2 )N(C 6 H 5 )H. 3

When phenylbenzenylamidine is heated with carbon disul-
phide, its thiocyanate is obtained together with thiobenzanilide ;
an intermediate product is probably first formed and then
decomposed at the higher temperature : 4

/NH\

C 6 H 5 .C^-S-^CS = C 6 H 5 .CS.N(C 6 H 5 )H 4 NOSH.

\N(C 6 H 5 )H

Symmetric diphenylbenzenylamidine , C 6 H 5 . C( N C 6 H 5 )N (C 6 H 5 )H.
This compound was first prepared by Gerhardt, who obtained
it by warming benzanilide with phosphorus pentachloride
and then heating the product with aniline. 5 The compound
C 6 H 5 .CC1 2 .N(C 6 H 5 )H is first formed, and is converted, with loss
of hydrochloric acid, into bemanilidimidochloride, which acts
upon the aniline in the following manner :



N(C 6 H 6 )H 2 = C 6 H 5 .C + HCL

C1



Ber. Deutsch. Chem. Gcs. xi. 4.

Bernthsen, Ann. Chem. Pharm. clxxxiv. 348.

Bernthsen and Szymanski, Ber. Deutsch. Chem. Gcs. xiii. 917.

Bfirnthsen. Ann. Chem. Pharm. cxcii. 31.

Ann. Chem. Pharm. cviii. 217.



204 AROMATIC COMPOUNDS.

Benzanilidimidochloride crystallizes from petroleum ether in
large, transparent, lustrous plates, melts at 39 40, and boils
without decomposition at about 310; water decomposes it
rapidly, benzanilide being reproduced. 1

Diphenylbenzenylamidine is also formed by the action of
aniline on benzenyl trichloride, 2 and by heating benzanilide with
aniline hydrochloride and phosphorus trichloride. 3 It is slightly
soluble in water, readily in alcohol, and crystallizes in needles,
melting at 144 (Wallach and Hoffmann). On heating with
hydrochloric acid to 150, it decomposes into benzoic acid and
aniline, while, on heating with sulphuric acid, thiobenzanilide
and phenyl mustard oil are formed (Bernthsen). Its hydro-
chloride, C 19 H 16 N 2 .C1H, is only very slightly soluble in cold
water and crystallizes from alcohol in needles.

Asymmetric diphenylbenzenylamidine, C 6 H 5 C(NH)N(C 6 H 5 ) 2 , is
prepared by heating benzonitril with diphenylamine hydro-
chloride to 180 190. It is exceptionally soluble in alcohol
and tolerably in ether, from which it crystallizes in thin, yellowish,
alkaline, rhombic tablets, melting at 112. It decomposes on
boiling into diphenylamine and benzonitril ; when it is heated
with carbon disulphide, its thiocyanate is formed together with
diphenylthiobenzanilide, C 6 H 5 .CS.N(C 6 H 5 ) 2 . Its hydrochloride
crystallizes in needles or moiioclinic prisms, which are readily
soluble in water (Bernthsen).

Diphenylparamidobenzenylamidine or Carbotriphenyltriamine,
C 19 H 17 N 3 , was first prepared by Hofmann by heating aniline
with tetrachloromethane ; 4 it is more readily formed, however,
from tetrabromomethane. 5 Weith obtained it by heating para-
nitrobenzoic acid with aniline and phosphorus trichloride, and
reducing the diphenylparanitrobenzenylamidine thus formed
with tin and hydrochloric acid, 6 while Michler and Walder
prepared it by the action of aniline on trichloromethylsulphonyl
chloride, CC1 3 .SO 2 C1. 7 It is insoluble in water, slightly soluble
in ether, and crystallizes in long tablets, melting at 198. On
distillation it decomposes into hydrocyanic acid, benzonitril,
ammonia, aniline, and diphenylamine, while on heating with

Wallach and Hoffmann, Ann. Chem. Pharm. clxxxiv. 79.

Limpricht, ibid, cxxxv. 82 ; Dobner, Ber. DcutscJi. Chem. Get. xv. 233.

Hofmann, Zeitschr. Chem. 1866, 165.

Hofmann, Jahresber. Chem. 1858, 351.

Bolas and Groves, Ann. Chem. Pharm. clx. 173

Ber. Dcutsch. Chem. Gcs. xii. 101.

Ibid. xiv. 2174.



PHENYLENEBENZENYLAMIDINE. 205

hydrochloric acid to 160, aniline and paramidobenzoic acid are
formed :



\






N(C 6 H 6 )H



2E 2 = H 2 N.C 6 H 4 .C0 2 H +



2N(C 6 H 5 )H 2 .

Phenylenebenzenylamidine, C 13 H 10 N 2 , was termed anhydro-
lenzodiamidobenzene by Hiibner, and is obtained by heating
benzoylorthodiamidobenzene :

NH 2

NH/ N



C 6 H 4 < CO.C 2 H 5 = C 6 H 4 < __ J)C.C 6 H 5 + H 2 O.



It may also be easily prepared by reducing benzoylorthonitro-
anilide with tin and hydrochloric acid, the rise of temperature
caused by the reaction being sufficient to bring about the forma-
tion of the anhydro-base. It is slightly soluble in water, readily
in alcohol, and crystallizes from glacial acetic acid in lustrous
tablets, melting at about 280 ; the hydrochloride, C 13 H 10 N 2 .C1H,
forms long needles, which are readily soluble in water.

The base is not attacked by benzoyl chloride even at 260 ;
on heating with iodine and alcohol, however, the periodide,
C 13 H 10 N 2 .IH.I 2 , is formed, and crystallizes in small plates which
resemble iodine, but have a green surface lustre and are con-
verted by boiling with water into the hydriodide, C 13 H 10 N 2 .IH +
H 2 0, crystallizing in long, light yellow needles.

Dimethyl phenylenebenzenylamide ammonium iodide, C 13 H 10 N 2
(CH 3 ) 2 I. When the anhydro-base is heated with methyl iodide
to 180, the periodide, C 13 H 10 N 2 (CH 3 ) 2 I S , is formed ; this sub-
stance crystallizes in long, brownish red needles, and is con-
verted into the mono-iodide by boiling in alcoholic solution with
freshly precipitated lead hydroxide. This compound crystallizes
from hot water in long needles ; caustic potash precipitates from
its solution the hydroxide, C 13 H 10 N 2 (CH 3 ) 2 OH, in white flocks,
which melt at 152 and are insoluble in water, but dissolve
readily in hot alcohol. Its solution has a bitter taste, and its
salts crystallize well ; it has the following constitution :

OH



AROMATIC COMPOUNDS.



Phenylenenitrobenzcnylamidine, C 13 H 9 (NO 2 )N 2 , is obtained by
dissolving the anhydro-base in fuming nitric acid ; it crystallizes
from alcohol in yellowish, microscopic needles, molting at 196.
It is reduced by tin and hydrochloric acid to amiddbenzenyl-
phenylene-amidinc, C 13 H 9 (NH 2 )N 2 , which crystallizes from alcohol
in small needles, melting at 240. The hydrochloride, C 13 H 9
(NH 2 )N 2 (C1H) 2 , forms small plates, which are very soluble in
water; the sulphate, C 13 H 9 (NH 2 )N 2 .SO 4 H 2 + 2H 9 O, is only
slightly soluble in hot water, and crystallizes in broad needles.

A large number of other similar anhydro-bases is also
known. 1 The following compounds belong to the same class.

Benzenylamidophenate, C 13 H 9 NO. Ladenburg prepared this
compound by heating ortho-amidophenol with benzoyl chloride,
and by the distillation of the former with phthalic anhydride :



64 C 6 H 4 = C 6 H 5 .C >C 6 H 4 +C0 2 +H 2 0.

XKX H(K X CK

It crystallizes from dilute alcohol in lustrous plates, melts at
103, and boils at 314 317 ; it combines with acids to form
unstable salts; the platinichloride, (C 13 H 10 NO) 2 PtCl 6 , crystal-
lizes from alcohol which contains hydrochloric acid in yellow
prisms. On heating the base with concentrated hydrochloric
acid to 150, it decomposes into benzoic acid and orthamido-
phenol. 2

Benzcnylamidothiophenate, C 13 H 9 NS, is formed by boiling
benzanilide with sulphur : 3

C 6 H 5 .CO.NH(C 6 H 6 ) + S = C 6 H 5 .C^ \C 6 H 4 + H 2 0.

It is also obtained by the action of benzoyl chloride on ortho-
amidothiophenol, as well as by heating the latter with benz-
aldehyde, or benzonitril. 4 It is formed in smaller quantity,
together with other products, when phenyl mustard oil is heated
with benzoyl chloride. 5 It crystallizes from alcohol in needles,
which, especially when heated, smell like tea-roses and
geraniums, melt at 115, and boil at about 360. Like the
preceding compound, it is a base and forms a platinichloride

1 Hiibner, Ann. Chem. Pharm. ccviii. 278 ; ccix. 339 ; ccx. 328.

2 Ber. Dewtsch. Chem. Ges. ix. 1526.

3 Hofmann, ibid. xii. 2359.

4 Ibid. xiii. 1223. s j^. xiii. 17.



BENZHYDROXAMIC ACID. 207

which crystallizes in long needles. It is not attacked when
heated with concentrated hydrochloric acid to 200 ; on fusion
with caustic potash it is resolved into amidothiophenol and
benzoic acid.



BENZENYLOXIME COMPOUNDS.

2118 The three hydrogen atoms of hydroxylamine can, as was
pointed out by Lossen, be successively replaced by benzoyl :

Benzhydroxylamine, NOH 2 (CO.C 6 H 5 ),
Dibenzhydroxylamine, NOH(CO.C 6 H 5 ) 2 ,
Tribenzhydroxylamine, NO(CO.C 6 H 5 ) 3 .

The last of these compounds is an indifferent substance ; the
two others are acids, and have therefore been called by Lossen
benzhydroxamic acid and dibenzhydroxamic acid. 1 Certain
cases of physical isomerism and of metamerism are characteristic
of them and their derivatives. Lossen showed somewhat later
that these peculiarities as well as numerous decompositions of the
compounds in question can readily be explained if benzhydrox-
amic acid be looked upon as an oximido-compound of benzenyl ; 2
its formation is then expressed by the following equations :

/N.OH
C 6 H 5 .COC1 + H 2 N.OH = C 6 H 5 .C^ + H 2 O.

.N.OH ..N.OH

C 6 H 5 .C^ + H 2 = C H 5 .C^ + HC1.

\C1 \OH

It is, however, also possible that the hydroxylamine forms an
additive compound with the benzoyl chloride, and that hydro-
chloric acid is then given off : 3






/OH /OH

W^NttOH = C 6 H,C/_ +Htt



1 Ann. Chem. Pharm. clxi. 347.

2 Ber. Deutsch. Chcm. Gcs. xvi. 87-3

3 Ibid, xviii. 1189.



208 AROMATIC COMPOUNDS.

The other compounds are then formed by the replacement of



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