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X C0 2 H
tained in the preparation of the preceding compound, and also in

1 Klepl, Journ. Prakt. Chem. [2] xxv. 525 ; xxviii. 193.


the amorphous mass formed by the distillation of parahydroxy-
benzoic acid, from which it may be extracted by absolute alcohol.
It is a white, non-crystalline powder, which is slightly soluble in
alcohol and ether, but insoluble in water and chloroform; it
melts at 280, and readily dissolves in alkalis, being gradually
converted into parahydroxybenzoic acid, while it is not altered
by boiling water. When the acid is suspended in a small
quantity of water and treated with sufficient caustic soda to
effect solution, the compound C 21 H 13 O 7 Na is precipitated in
needles after some time. The acetyl compound, C 21 H 13 (C 2 H 3 0)O 7 ,
is formed by heating the acid with acetic acid ; it crystallizes in
needles melting at 230.

Parahydroxybenzide, (C 7 H 4 O 2 ) n , is the final product of the
action of heat upon parahydroxybenzoic acid, and forms a white,
amorphous powder, which is insoluble in the ordinary solvents,
and carbonizes at 350 without previously melting. Boiling
concentrated caustic potash converts it into parahydroxybenzoic
acid ; on heating with concentrated sulphuric acid, parahydroxy-
benzoylsulphuric acid is obtained, while parachlorobenzenyl
trichloride is formed by the action of phosphorus chloride at 300
(p. 196).

Anisic anhydride, (C 6 H 4 (OCH 8 }CO) 2 O, is obtained by the
action of phosphorus oxychloride on sodium anisate. It crys-
tallizes from ether in small, silky needles, Avhich melt at 90
and volatilize at a higher temperature without decomposition l

Methylparahydroxylenzoyl chloride, or Anisyl chloride, C C H 4
(OCH 3 )COC1, is formed by the action of phosphorus penta-
chloride on anisic acid. 2 It forms long needles, which cannot be
volatilized. 3

Paracarlonylphcnylphosphoryl chloride, C C H 4 (OPOC1.,)COC1 )
is prepared by the action of phosphorus pentachloride on de-
hydrated parahydroxybenzoic acid, the reaction being more
violent than in the case of salicylic or metahydroxybenzoic acids.
It boils at 176 under a pressure of 13 14 mm., and is a
powerfully refractive liquid. Water converts it into paracarbonyl-
orthophosphoric acid, C 6 H 4 (CO 2 H)PO(OH) 2 , which crystallizes in
fine, white plates, melting at 200 ; it is only decomposed by
water at 150 160, parahydroxybenzoic and phosphoric acids
being formed. When the chloride is distilled slowly under the
ordinary pressure, it passes over almost unaltered, only a small

1 Pisani, Ann. Cfam. Pharm. cii. 284. - Cahours, ibid. Lxx. 47.

:t Lessen, ibid, clxxv. 284.


portion decomposing into phosphorus oxychloride and para-
chlorobenzoyl chloride.

The behaviour of this chloride towards a second molecule of
phosphorus pentachloride is of considerable interest, since it
differs from that of its isomerides inasmuch as no parabenzenyl-
trichlorophosphoryl chloride is formed, but the compound
decomposes into phosphorus oxychloride and parachlorobenzoyl
chloride, the latter being then partially converted into para-
chloiobenzenyl trichloride. The phenol-oxygen is therefore
more readily replaced by chlorine when it occupies the para-
position than when it is present in either an ortho- or
meta-disubstituted compound. 1

Parahydroxylenzamide, C 6 H 4 (OH)CO.NH 2 +H 2 O, is obtained
by heating the ethyl ether with ammonia under pressure. It
crystallizes from hot water in strongly lustrous, rhombic needles,
which lose their water of crystallization at 100 and then melt
at 162.

Anisamide, C 6 H 4 (OCH 3 )CO.NH 2 , was prepared by Cahours
from the chloride by the action of ammonia ; it crystallizes in
prisms, melts at 137 138, sublimes in broad plates and boils
at 295 (Henry).

Parahydroxylenzanilidc, C C H 4 (OH)CO.NH(C 6 H 5 ), is formed
when the acid is heated with aniline and the product treated
with phosphorus trichloride. It crystallizes from hot water in
yellowish, lustrous plates, melting at 196 197. It forms
salts of potassium and sodium, which are readily soluble and
crystallize well (Kupferberg).

Anisanilide, C 6 H 4 (OCH 3 )CO.NH(C 6 H 5 ), was obtained by
Lessen as a product of the distillation of benzanishydroxamic
acid (p. 340). It is slightly soluble in cold alcohol, and
crystallizes in rhombic plates, melting at 168 169.

Parahydroxylenzuric acid, C 6 H 4 (OH)CO.NH.CH 2 .CO 2 H, ap-
pears, together with parahydroxybenzoylsulphuric acid, in the
urine of the dog after the administration of parahydroxybenzoic
acid ; it crystallizes in short prisms, which are tolerably soluble
in water (Baumann and Heiter).

Anisnric acid, C 6 H 4 (OCH 3 )CO.NH.CH 2 .CO 2 H, was obtained
by Cahours from silver amido-acetate and anisyl chloride, 2 and is
also found in the urine after anisic acid has been taken ; 3 it

1 Anschiitz, private communication.

2 Ann. Chrm. Phnrm. cix. 32.

3 Griibe and Schultzen, ibid, cxlii. 348.


forms foliaceous crystals, which are readily soluble in hot

Parahydroxylenzonitril, C 6 H 4 (OH)CN, is formed when am-
monium parahydroxybenzoate mixed with phosphorus pentoxide
is distilled in a current of carbon dioxide (Hartmann), and
by the action of ammonia on parahydroxybenzide mixed with
pumice-stone and heated to 250 (Klepl). It crystallizes from
hot water in rhombic tablets, which melt at 113, and have a
sweet but pungent taste ; it forms a series of salts in which the
phenol-hydrogen is replaced by the metal.

Anisonitril, C 6 H 4 (OCH 3 )CN. Henry obtained this substance
by distilling the amide with phosphorus pentachloride. It
crystallizes from hot water in small needles, and from ether in
long, white, lustrous prisms, has a penetrating, characteristic
rank odour, melts at 56 -57, and boils at 253 254. l


2186 Chloroparahydroxybcnzoic acid, C 6 H,C1(OH)CO 2 H,
(3:4: 1), is formed by heating parahydroxybenzoic acid with
antimony pentachloride, 2 and by the action of alcoholic potash
on orthochlorophenol at 125 136. 3 It is slightly soluble in
cold, more readily in hot water, and crystallizes in small needles,
which melt at 169 170, and sublime without decomposition.
Ferric chloride produces a brown precipitate in a concentrated
solution ; phosphorus pentachloride converts it into the chloride
of a-dichlorobenzoic acid (Lossner).

Dichloroparahydroxybenzoic acid, C 6 H 2 C1 2 (OH)CO 2 H, has also
been prepared by Lossner ; it crystallizes in fine needles, which
melt at 255 256.

Dibromoparahydroxybenzoic acid, C 6 H 2 Br 2 (OH)CO 9 H, (3 : 5 :
4 : 1), has been obtained from dibromanisic acid. It is scarcely
soluble in water, and crystallizes from alcohol in needles, which
melt with decomposition at 266 268, but sublime at a lower
temperature. A monobromoparahydroxybenzoic acid is not
known ; when bromine water is added to a solution of para-

1 Bcr. Devtech. Chcm. Gen. ii. 666.

2 Lossner, Journ. Prakt. Chem. [2] xiii. 432.

3 Hasse, Bcr. Dcutsch. Chcm. Gcs. x. 2192.


hydroxybenzoic acid, a precipitate of tribromophenol is produced
(Earth and Hlasiwetz).

lodoparakydroxybenzoic acid, 2C 6 H 3 I(OH)CO ;i H + H 2 O, is
formed when parahydroxybenzoic acid is boiled with water,
iodine and iodic acid ; it crystallizes from hot water in small
needles, which become anhydrous at 100 and then melt at
192 . 1

Di-iodoparahydroxybenzoic acid, C 6 H 2 T 2 (OH)C0 2 H, is formed
together with the preceding compound, and crystallizes in small
needles, which are scarcely soluble in water, but readily in

Nitroparahydroxybenzoic acid, C 6 H 3 (NO 2 )(OH)CO 2 H, (3:4: 1).
Griess obtained this compound by the action of boiling potash on
S-mtro-amidobenzoic acid. 2 It is also formed in small quantity,
together with /3-nitro-salicylic acid, by heating orthonitrophenol
with alcoholic potash and tetrachloromethane (Hasse). It crystal-
lizes from boiling water in yellowish needles, melting at 185.
Its solution is not coloured by ferric chloride.

Basic barium nitroparahydroxybenzoate, C 7 H 3 N0 5 Ba + H 2 O, is
obtained by adding barium chloride to a hot, ammoniacal solu-
tion of the acid. It forms yellowish red, lustrous plates.

Dinitroparahydroxybenzoic acid, C 6 H 2 (NO 2 ) 2 (OH)CO 2 H, (3:5:
1:4) is formed when a boiling solution of dinitroparamidobenzoic
acid is treated with nitrous acid or with caustic potash. It is
slightly soluble in cold, more readily in hot water, and crystallizes
in large, thin tablets, -which are coloured light yellow to bronze,
and melt at 235 237 . 3

Its salts are coloured yellow or orange- red, and crystallize

Earth has prepared a mono- and a di- nitro-acid by the action
of nitric acid on parahj'droxybenzoic acid, both of which seem to
be different from the preceding compounds.

Amidoparahydroxybenzaic acid, C 6 H 3 (NH 2 )(OH)CO 2 H. Earth
obtained this substance by the reduction of his nitroparahydroxy-
benzoic acid. It crystallizes in needles and forms a sulphate
which also crystallizes in needles, and gives a dark cherry-red
colouration with concentrated nitric acid.

Sulphoparahydroxybenzoic acid, C 6 H 3 (S0 3 H)(OH)CO 2 H, was
prepared by Kolle by the action of sulphur trioxide on para-

1 Pelzer, Ann. Chem. Pharm. cxlvi. 288.

" Bcr. Deutech. Chem. Oes. v. 856.

3 Salkowski, Ann. Chem. Pharm. clxiii. 36.


hydroxybenzoic acid. 1 It is also obtained when the latter, or
parahydroxybenzide, is heated with concentrated sulphuric acid
(Klepl), and forms deliquescent needles, which are insoluble in
ether. Its solution is coloured blood-red by ferric chloride ; on
fusion with potash, it yields protocatechuic acid.

Acid potassium sulphoparahydroxybenzoate, C 7 H 5 SO 6 K + H.,O,
is a very characteristic salt, since it is even less soluble in water
than acid potassium tartrate. It crystallizes from a hot solution
in quadratic tablets or prisms, and from a less concentrated
solution in rectangular plates which are obliquely striated (Klepl).

Parahydroxy~benzoyl sulphuric acid, C 6 H 4 (SO 4 H)CO 2 H, occurs
as an alkali salt in the urine of the dog after administration of
parahydroxybenzoic acid. The potassium salt, C 6 H 4 (SO 4 K)C0 2 K,
is obtained by heating an alkaline solution of parahydroxybenzoic
acid with potassium disulphate, and crystallizes in lustrous
plates or tablets, which decompose at 250 with formation
of potassium sulphate and anhydrides of parahydroxybenzoic
acid. 2


2187 Chloranisic acid, C 6 H 3 C1(OCH 3 )CO 2 H, is formed by the
action of chlorine on fused anisic acid, and crystallizes from dilute
alcohol in needles or rhombic prisms, which melt at 176 and
volatilize without decomposition. 3

Dichloranisicacid, C 6 H 2 C1 2 (OCH 3 )CO 2 H, is obtained, together
with chloranil, by heating anisic acid with hydrochloric acid and
potassium chlorate ; it crystallizes from alcohol in large needles
melting at 196 . 4

Bromanisic acid, C 6 H 3 Br(OCH 3 )CO 2 H, is formed by the action
of bromine on anisic acid (Cahours), the latter being kept
covered with hot water. 5 It crystallizes from alcohol in needles
which melt at 213 214 and sublime in small plates.

Dibromanisic acid, C 6 H 2 Br 2 (OCH 3 )CO 2 H. Reinecke pre-
pared this substance by heating anisic acid to 120 with bromine
and water ; it crystallizes in long needles melting at 207. On

1 Ann. Chcm. Pharm. clxiv. 150.

- Baumann, Ber. IkMtsch. Chcm. Ges. xi. 1916.

3 Cahours, Ann. Chan. Pharm. Ivi. 312.

4 Reinecke, Zeitschr. Chcm. 1866, 366.

5 Salkowski, Ber. Deutsch. Chem. Ges. vii. 1013.


further treatment with bromine, tribromanisoil and tetrabromo-
quinone are formed, while fuming nitric acid converts it into
dibromonitro-anisoil, CgH^Br./NO^OH, (3:5:4:1), which was
previously obtained by Korner in a different manner, the con-
stitution of the acid being thus shown. 1 When its sodium salt
is distilled with lime, the methyl ether is formed, together
with the basic sodium salt of dibromoparahydroxybenzoic
acid: 2

/CO 2 Na .CCLOCH. /CO,Na.

2C 6 H 2 Br 2 < = C 6 H 2 Br 2 < + C 6 H 2 Br /

\OCH 3 X OCH 3 \ONa

This ether crystallizes from alcohol in lustrous needles melting
at 91-5 92.

The dibromoparahydroxybenzoic acid is also obtained by
heating dibromanisic acid with hydriodic acid. 3

lodanisic acid, C 6 H 3 I(OCH 3 )CO 2 H, was prepared by Griess
from diazo-amido-anisic acid, 4 while Peltzer obtained it by
heating anisic acid to 145 150 with iodine and iodic acid. 5 It
crystallizes from alcohol in needles, which melt at 234*5, and
sublime in small plates.

Nitro-anisic acid, C 6 H 3 (NO 2 )(OCH 3 )C0 2 H, was obtained by
Cahours as a product of the action of nitric acid on anisic acid
and anisoil. 6 In order to prepare it, anisoil is allowed to drop
into ten times its weight of warm nitric acid, of specific
gravity T4, the mixture boiled for a short time, and the acid
then precipitated by water ; it is well washed and finally freed
from an admixed oil by solution in ammonia and reprecipitation
by hydrochloric acid. 7 Nitro-anisic acid is slightly soluble in
water, and crystallizes from alcohol in compact prisms melting at
189. On heating with water to 220, it decomposes into ortho-
nitrophenol, methyl alcohol and carbon dioxide, 8 while aqueous
ammonia at 140 170 converts it into 8-nitro-amidobenzoic
acid. 9

Its salts have been investigated by Engelhardt. 10
Dinitro-anisic acid, C 6 H 2 (NO 2 ) 2 (OCH 3 )CO 2 H. Salkowski and
Rudolph prepared this substance by dissolving anisic acid in

Balbiano, Gaz. Chim. Ital. xiv. 9. 2 Ibid. xiii. 65.

Alessi, ibid. xv. 242. 4 Ann. Chem. Pharm. cxvii. 54.

Ibid, cxlvi. 302. 6 Cahours, ibid. xli. 71.

Salkowski, ibid, clxiii. 6.

Salkowski and Rudolph, Ber. Dcutsch. Chem. Ges. x. 1254.
Salkowski, Ann. Chem. Pharm. clxxiii. 35.
1 Zinin, ibid. xcii. 327 ; Cahours, ibid. cix. 21.


portions of 40 grammes at a time in a well-cooled mixture of
sulphuric and nitric acids, 160 grammes of the former and 140
of the latter being required for each portion of anisic acid ;
notwithstanding the low temperature, carbon dioxide is evolved
and di- and tri-nitro-anisoil are formed. The dinitro-anisic acid
separates from the acid solution on standing, and is then dissolved
in a cold, dilute solution of sodium bicarbonate, re-precipitated
by alcohol and finally purified by re-crystallization from dilute
alcohol. It forms yellowish needles melting at 181 182, and
on boiling with caustic soda decomposes into methyl alcohol and
dinitroparahydroxybenzoic acid, while it is immediately converted
into chrysanisic acid by boiling, concentrated ammonia (p. 258).

Amido-anisic acid, C 6 H 3 (NH 2 )(OCH 3 )CO 2 H, is obtained by
reducing nitro-anisic acid with alcoholic ammonium sulphide. 1

It is slightly soluble in water, readily in alcohol, and crystal-
lizes in long, thin, four-sided prisms, which melt at 180 and are
decomposed into carbon dioxide and anisidine when heated with
caustic baryta (Part III. p. 283).

Methyl amido-anisate, C G H 3 (NH 2 )(OCH 3 )CO 2 .CH 3 , was pre-
pared by Cahours from the methyl ether of nitro-anisic acid by re-
duction ; it crystallizes in prisms which readily dissolve in alcohol.

Methylamido-anisicacid, C C H 3 (NH.CH 3 )(OCH 3 )C0 2 H. Griess
obtained this substance by heating potassium amido-anisate with
methyl iodide. It is slightly soluble in hot water and cold
alcohol, but more readily in hot alcohol, and melts above 200 .' 2

Trimethylamido-anisic acid, or Trim t thylanise-l>ctainc,G ll ti 1 r^NO s
+ 5H. 2 O, is formed by the action of methyl iodide and caustic
potash on anisic acid, and crystallizes from water in well-
formed, vitreous prisms, which have a bitter taste and are neutral
to litmus paper.

It is completely converted by distillation into the metameric
methyl ether of dimethylamido-anisic acid :

/OCH 3 /OCH 3

C 6 H 3 -CO-0 = C H / CO.OCH 3 .
\ / \N(CH 3 ) 2

N (CH 3 ) 3

The latter substance is a yellowish liquid, which has a faint
aromatic odour and boils at 288 . 3

1 Zinin, Ann. Chcm. Pharm. xcii. 327 ; Cahours, ibid. cix. 21.

2 er. Deutsch. Chcm. Ges. v. 1042,

3 Griess, ibid, vi. 537.



2188 These bodies, which correspond to the benzenyloxime
compounds (p. 207), are prepared in an exactly similar manner,
anisyl chloride being gradually added to a solution of hydroxyl-
amine hydrochloride, which is kept faintly alkaline by the addition
of dilute carbonate of soda solution. A mixture of anishydrox-
amic acid, di-anishydroxamic acid and anisic acid is thus
obtained. Boiling water extracts from this a portion of the
anisic acid and all the anishydroxamic acid, these being sub-
sequently separated by means of their barium salts, that of the
former being soluble while that of the latter is insoluble in water.
The dry mixture of the two acids may also be extracted with
warm absolute ether, in which anishydroxamic acid is almost
insoluble. The di-anishydroxamic and anisic acids are separated
by treatment with a cold solution of sodium carbonate, which
dissolves the latter completely, while only a small portion of the
former enters into solution. The liquid is filtered rapidly,
because di-anishydroxamic acid is easily decomposed by carbon-
ate of soda, the filtrate almost neutralized with hydrochloric
acid, and then saturated with carbon dioxide, all the di-anis-
hydroxamic acid present being thus precipitated. 1

Anishydroxamic acid, CH 3 O.C 6 H 4 .C(OH)NOH, is slightly
soluble in cold, readily in hot water and alcohol, but is almost
insoluble in ether; it crystallizes in small plates, melting at
156 157, and is coloured deep violet by ferric chloride. The
acid potassium salt, C 8 H 8 KNO 3 + C 8 H 9 NO 3 , forms long, flat
needles, which are tolerably soluble in cold water. Lead acetate
produces a thick, white precipitate 2 of C.,H 3 O 9 PbC 8 H 8 NO 3 .

Ethyl anishydroxamate, CH 3 O.C 6 H 4 .C(OH)NOC 2 H 6 , is formed
l>y the action of anisyl chloride on ethylhydroxylamine ; it is
insoluble in water, readily soluble in alcohol, less easily in ether,
from which it crystallizes in tablets, which melt at 84 and
have feeble acid properties. On heating with concentrated
hydrochloric acid, it is split up into anisic acid and ethyl-
hydroxylamine. 3

Ethylanishydroxamw acid, CH 3 O.C H 4 .C(OC,H 5 )NOH, is

1 LOSSCD, Ann. Chcm. Pharm. clxxv. 284.
- Hodges, ibid, clxxxii. 218.
3 Pieper, ibid, ccxvii. l<j.

z 2


obtained by heating the ethyl ether of anisbenzhydroxamic
acid with caustic potash. It is precipitated by carbon dioxide
as an oily liquid, which solidifies to a crystalline mass, melting
at 32. It is readily soluble in alcohol and ether, and decomposes
on heating with hydrochloric acid into ethyl anisate and
hydroxylamine. 1

Dianishydroxamic acid, CH 3 O.C 6 H 4 .C(NO.CO.C 6 H 4 .OCH 3 )OH,
is scarcely soluble in water and ether, slightly in alcohol,
and crystallizes in needles, melting at 142 143. It is de-
composed by baryta water into anisic acid and anishydroxamic

Benzanishydroxamic acid, C 6 H 5 .G(NO.CO.C 6 H 4 .OCH 3 )OH, is
formed by heating benzhydroxamic acid to 100 with anisyl
chloride. It crystallizes from alcohol in needles or prisms, which
melt at 131 132. On heating with baryta water, it decom-
poses into anisic acid and benzhydroxamic acid, while boiling
water splits it up into carbon dioxide, anisic acid and diphenyl
urea. When heated alone, it yields carbon dioxide, phenyl
isocyanate, anisic acid and anisanilide,C 6 H 5 .NH(CO.C 6 H 4 .OCH 3 ).

a-Ethylbenzanishydroxamate, or Benzanisethylhydroxylamine,
C 6 H 5 .C(NO.CO.C 6 H 4 .OCH 3 )OC 2 H 5 , is obtained by the action of
ethyl iodide on silver benzanishydroxamate. It crystallizes from
a mixture of ether and benzene in thick, monoclinic tablets,
melting at 74 (Pieper). It is decomposed by caustic potash
into anisic and a-ethylbenzhydroxamic acids, and by hydrochloric
acid into anisic acid, ethyl benzoate and hydroxylamine.

ft-Ethylbenzanishydroxamate is formed by the action of anisyl
chloride on a- or/3-ethylbenzhydroxamic acid, and separates from
ether in monoclinic crystals, melting at 89. On heating with
concentrated caustic potash solution, it decomposes into anisic
acid and /3-ethylbenzhydroxamic acid, while on dry distillation
it decomposes into benzonitril, anisic acid and aldehyde.

Anisbenzhydroxamic acid, CH 3 O.C 6 H 4 C(NO.CO.C 6 H 5 )OH, is
obtained from anishydroxamic acid and benzoyl chloride ; it
crystallizes in needles or prisms, which melt at 147 148, and
decompose at a higher temperature into carbon dioxide, benzoic
acid, anisoil isocyanate, CON.C 6 H 4 .OCH 3 , and benzoylanisidine.
NH(CO.C 6 HJC 6 H 4 .OCH 3 .

Ethyl anisbenzhydroxamate, or Anisoenzethylhydroxylaminr,
CH 3 O.C 6 H 4 C(NO.CO.C 6 H 5 )OC 3 H 5 , crystallizes in short, four-
sided, asymmetric pyramids, melts at 79 and is decomposed
1 Eisler, Ann. Chem. Pharm. clxxv. 338.


by caustic potash into benzole acid and ethylanishydroxamic

Benzethylanishydroxylaminc, C 6 H 5 C(N O C 2 H 5 )0. C O.C 6 H 4 .
OCH 3 , is obtained by the action of anisyi chloride on the silver salt
of ethylbenzhydroxamate, and separates from ether in asymmetric
crystals, melting at 64. It is decomposed by highly concentrated
caustic potash into anisic acid and ethylbenzhydroxamate.

is formed when a solution of ethylanishydroxamate in caustic
potash is treated with benzoyl chloride, and forms monosymmetric
crystals, melting at 93 94. It is split up into benzoic acid
and ethyl anishydroxamate on heating with caustic potash. 1

2189 Hydroxylamine Derivatives containing three Acid, Radicals
are formed by the action of anisyi or benzoyl chloride on the
silver salts of the dihydroxamic acids. They are insoluble in
water and sodium carbonate solution, and only very slightly
soluble in cold alcohol. On heating with hydrochloric acid, the
radical which was last introduced is split off. 2

Jsro.co.c 6 H 5


\O.CO.C 6 H 4 .OCH 3


a) Long, monosymmetric needles or prisms . 110 110'5
/3) Small crystals 109 -110

X NO.CO.C 6 H 4 .OCH 3

\O.CO.C 6 H 5


a) Short, asymmetric prisms 113 114

/3) Long, rhombic prisms 124 125

7) Monosymmetric tablets ; decompose on fusion

NO.CO.C 6 H 6

\OCO.C 6 H 5


a) Lustrous monoclinic tablets 137 137'5

Very small crystals, usually opaque . . . 109'5 110'5
1 Pieper, Ann. Chcm. Pharm. ccxvii. 1. 3 Lossen, ibid, clxxxvi. 1.



NO.CO.C 6 H 5
CH 3 O.C C) H 4 .C^

\OCO.C 6 H 4 .OCH 3


a) Very small, monosymmetric tablets .... 152 153
/3} Monosymmetric tablets 1-48 149


/NO.CO.C 6 H 4 .OCH 3

CH,O.C fl H 4 .CC

\OCO.C 6 H 5

Large, monosymmetric crystals with many faces . 1 47'5

^NO.CO.C C H 4 .OCH 3

\O.CO.C 6 H 4 .OCH 3


a) Short, asymmetric columns 137'5 138'5

/?) Asymmetric tablets 137'5 138

Lossen remarks concerning these compounds : " The twelve
substances described above afford an additional proof of the well-
established fact that there are two kinds of isomerism, which
must be carefully distinguished from one another. Seven
isomeric substances were obtained as the products of three
different methods of preparation, three being yielded by one
method and two by each of the others ; three further methods
of preparation, different from the preceding, gave five isomeric
bodies, two being formed by each method. Isomerides are,
therefore, formed both by different methods and by one and the
same method, but the difference between two compounds which
are prepared by independent methods is not the same as that
existing between the isomeric products of a single method." 1

The latter, in fact, always give the same decomposition
products on treatment with hydrochloric acid or caustic potash.
1 Loc. cit. and Bcr. Deutsch. Chcm. Gcs. xviii. 1180.


Thus benzole acid and dianishydroxamic acid are obtained by
the action of caustic potash upon the anisbenzanishydroxylamines,
the same products, together with anisic acid and anisbenzhydrox-

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