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acids which are of special interest, both on account of their similar
properties and analogous reactions, and from the fact of their
occurrence in the same plants. It is for this reason desirable
that the changes undergone by these compounds should be
represented by formula), and for this purpose it is necessary to sub-
stitute new expressions for some of the empirical formulas given
by Stenhouse, since the former agree equally well with the
experimental results and are also capable of representing the
decompositions and reactions of the substances in question.

a-Orsellic acid, then, is converted into two molecules of
orsellinic acid, the elements of water being taken up :

C 16 H 14 7 + H 2 = 2C 8 H 8 4 .

The former can also form orcinol with loss of carbon dioxide :
C 16 H 14 7 + H 2 = 2C 7 H 8 4 + 2C0 2 .

The conversion of orsellinic acid into orcinol takes place with
the separation of carbon dioxide :

C 8 H 8 4 = C 7 H 8 2 +C0 2 .

Erythric acid is resolved into picroerythrin and erythrelic
acid, which is undoubtedly orsellinic acid :

CH M 10 + H 2 = C 12 H 16 7 + C 8 H 8 4 .

Finally, picroerythrin decomposes into carbon dioxide, orcinol
and erythroglucin :

C 12 H 16 7 + H 2 = C0 2 + C 7 H 8 2 + C 4 H 10 4 .

He adds that erythric acid can yield twice as much orsellinic
acid as given by the equation, but Stenhouse considers this as j
improbable. In this case the formula of the former would be !
C 14 H 15 7 : 2

2C 8 H 8 4 + C 12 H 8 7 = 2C 14 H 15 7 + H 2 0.

1 Stenhouse, Phil. Trans. 1848, 63. s Ann. Chem. Pharm. Ixviii, 108.



ERYTHRIN AND PICROERYTHRIN. 431

Gerhardt came to the conclusion that orsellic acid has the
formula C 1G O U O 7 , and is identical with lecanoric acid, 1 while
Schunck expressed the opinion that the ethyl ether of orsellinic
acid is identical with that of lecanoric acid, just as is the case
with erythrin and pseudoerythrin. 2

Hesse then undertook a new investigation of these lichen
substances. He ascertained that the Angola lichen, which
comes into the market under many names, is Eucella fuciformis,
and retained Heeren's name of erythrin for the chromogen con-
tained in it, since it scarcely possesses the properties of an acid.
His analysis gave him results in accordance with Strecker's
second formula, which, however, he doubled and wrote C 28 H 30 14 .
The acid obtained from it by decomposition proved as Strecker
had correctly foreseen, to be identical with orsellinic acid. 3

Stenhoase confirmed these observations, and adopted the
same formula for erythrin, giving equations to explain its
changes and decompositions, 4 but, in spite of this, Strecker's
first formula has been shown to be correct.

After it had been recognized that erythroglucin or erythrol
as it is now called, is an alcohol, Berthelot suggested that
erythrin is the orsellinic ether of this, and de Luynes has
observed that it is in fact the di-acid ether of this alcohol, picro-
erythrin being the mono-acid derivative. 5 Orsellinic acid has
proved to be a dihydroxytoluic acid, and the compounds in
question have, therefore, the following constitution :

Erythrin :

CH 3 .C 6 H 2 (OH) 2 CO.(\

> 4 H 6 (OH),
CH 3 .C C H 2 (OH) 2 CO.(K

Picroery thrin :
CH 3 .C 6 H 2 (OH) 2 CO.OC 4 H 6 (OH) 3 .

Further investigations conducted by Hesse have finally decided
that the archil lichens which occur in commerce consist chiefly
of two species. Rocdla fuciformis (Acharius) comprises those
from Lima, Angola, Mozambique, Zanzibar and Ceylon; this
contains erythrin alone, while Eocella tinctoria (De Candolle),

1 Compt. Rend. Chim. 1849, 127. 2 Phil. Mag. xxxiii. 249.

s Ann. Chcm. Pharm. cxvii. 297. 4 Proc. Hoy. Soc. xii. 263.

5 Ann. Chem. Pharm. cxxxii. 355.



AROMATIC COMPOUNDS.



which comes from Cape Verde and the neighbouring islands,
contains a chromogen, lecanoric acid, 1 which is identical with
orsellic acid.

Stenhouse remarks on this point that the South American
lichens examined by him are also Itocella tinctoria. They are
sent into the market under the name of Valparaiso lichens, but
are seldom exported to England, while the Lima lichens (Bocella
fuciformis) are sent there in large quantities. 2

Lecanoric acid is monobasic and stands in the same relation
to orsellic acid as glycollic acid to glycoglycollic acid :

/OH
CH 3 .C 6 H 2 fOH

\co\

/0/>

CH 3 .C 6 H 2 ^-OH

\C0 2 H.

2231 Orsellinic acid, CH 3 .C 6 H 2 (OH) 2 C0 2 TI+H 2 0, is readily
prepared from erythrin by heating it on the water bath with
baryta water until barium carbonate commences to separate. A
few drops of the solution are then tested with hydrochloric acid
at short intervals, and as soon as a gelatinous precipitate is
no longer formed, hydrochloric acid is added to the solution,
the orsellinic acid being thus soon precipitated. It crystal-
lizes from acetic acid in stellate aggregates of needles, and
separates from dilute alcohol as a crystalline mass, which is
readily soluble in water, becomes anhydrous at 100, and melts
at 176, a gradual decomposition into carbon dioxide and orcinol
accompanied by violent frothing, taking place. The same
decomposition occurs on boiling with water or alkalis. Its
aqueous solution is coloured purple-violet by ferric chloride, and
gives an amorphous precipitate with an ammoniacal solution of
lead acetate.

Barium crsellinate, (C 8 H 7 O 4 ) 2 Ba, is extremely soluble in
water, and crystallizes from dilute alcohol in hydrated prisms,
which decompose even at 100 with formation of barium
carbonate.

Methyl orsellinate, C 8 H 7 O 4 (CH 3 ), is formed by boiling lecanoric
acid (Sclmnck) or erythrin (Stenhouse) with methyl alcohol, and
crystallizes in lustrous needles, or flat, pointed prisms, which

1 Ann. Chcm. Pharni cxxxix. 22. - Journ. Chem. Soc. v. 221.



LECANORIO ACID. 433

are readily soluble in water. It dissolves in alkalis and is
reprecipitated by acids.

Ethyl orsdlinate, C 8 H 7 O 4 (C. 2 H 6 ). The formation of this ether,
which was described by Heeren as pseudoerythrin, has been
frequently referred to in the preceding pages. It is slightly
soluble in cold, readily in hot water and alcohol, and crystallizes
in needles or small plates, which melt at 132. Its aqueous
solution is precipitated by lead acetate.

Amyl orsdlinate, CgHyO^CgH^), is prepared by boiling erythrin
with amyl alcohol. It is scarcely soluble in water, readily in
alcohol and ether, from which it crystallizes in vitreous prisms,
melting at 76 . 1

Orsellinic acid is decomposed by the action of bromine into
carbon dioxide and tribromorcinol ; if, however, the substances
are mixed in ethereal solution, substitution products are formed.

Dihromorsellinic acid, C 8 H 6 Br 2 O 4 , is slightly soluble in hot
water, readily in alcohol and ether, and crystallizes in small,
white prisms; its alcoholic solution is coloured a splendid
dark blue by ferric chloride, and blood-red by bleaching powder
(Hesse).

Pliosph orsellinic acid, C 40 H 36 P 4 24 . When orsellinic acid is
gradually heated with phosphorus oxychloride to 90 100, the
liquid becomes coloured brown, violet-green, and, finally, indigo-
blue. If it be now allowed to drop into ice water, phosphorsellinic
acid separates out, and may be purified by repeated solution in
water and precipitation with hydrochloric ac id or common salt.
It is an amorphous, indigo-blue powder, which takes a cupreous
lustre under strong pressure and readily forms deep blue solutions
in water and alcohol. The solution in 20,000 parts of water has
the colour of a concentrated solution of copper sulphate and a
distinct violet colouration is visible when 50,000 parts of water
are employed. It dissolves in alkalis, lime water and baryta
water with a violet-red colour ; the salts of the heavy metals
produce bluish violet, fiocculent precipitates.

Phosphcrsellinanilide, C 40 H 34 (C 6 H 5 .NH) 2 P 4 O 22 , is formed by
boiling the acid with aniline and alcohol ; it is a dark violet
powder, which is insoluble in water, but forms a splendid violet
solution in alcohol. 2

2232 Lecanoric acid or Diorsellinic acid, Ci H 14 7 + H 2 O, is,
according to Hesse, best prepared from the R tinctoria from Cape
Verde. The lichens are extracted with ether, and the greenish

1 Hesse, Ann. Chan. Pharm. cxxxix. 22. * Schiff, ibid, ccxxviii. 5t>.

VOL. III. PART IV. F F



434 AROMATIC COMPOUNDS.

white, crystalline residue left after the evaporation of the ether
dissolved in milk of lime, filtered, precipitated with sulphuric
acid and crystallized from alcohol. It is scarcely soluble in
cold water, but dissolves in 2,500 parts of boiling water, more
readily in alcohol and ether, and crystallizes in needles or
prisms, which become anhydrous at 100, melt at 153, and
simultaneously decompose with evolution of carbon dioxide.
The alcoholic solution is coloured dark purple-red by ferric
chloride and is not precipitated by lead acetate ; copper acetate,
however, produces a pale, apple-green precipitate on standing
(Schunck). It reduces ammoniacal silver solution on heating, and
is converted on boiling with water into orsellinic acid, and with
alcohol into its ether.

Barium lecanorate, (C 16 H 13 O 7 ) 2 Ba, separates from hot alcohol
in small, star-shaped aggregates of needles.

Substitution products are formed by the action of bromine on

an ethereal solution :

Melting-
point.

Dibromolecanoric acid, C 16 H 12 Br 2 O 7 , small white prisms . 179
Tetrabromolecanoric acid, C 16 H 10 Br 4 O 7 , pale yellow prisms 157

Both these bodies evolve carbon dioxide on fusion ; their
alcoholic solutions are coloured purple-red by ferric chloride and
blood-red by bleaching powder (Hesse).

Srytkrin, 2C 20 H 22 O 10 + 3H 2 O. In order to prepare this sub-
stance, 1 part of R.fuciformis is macerated for twenty minutes with
10 parts of milk of lime containing 1'6 per cent, of lime, filtered
and precipitated immediately with hydrochloric acid. The re-
sidue is treated a second time with milk of lime, which is then
employed for the extraction of a new quantity of lichen. The
precipitate is redissolved in milk of lime, the filtrate treated with
carbon dioxide and the precipitated mixture of calcium carbonate
and erythrin gently warmed with alcohol; hot water is then
added to the solution until a permanent turbidity is produced.
The erythrin separates on cooling in spherical crystalline masses,
which become anhydrous at 100 and melt at 137. It is
slightly soluble in cold water, with difficulty in ether, but
readily in alcohol ; ferric chloride added to the alcoholic solution
produces a purple-violet colouration, which changes on further
addition of the reagent to a brownish red precipitate.

Picroerythrin, C 12 H 16 O 7 + 3H. 2 O, is the first product of the
decomposition of erythrin by boiling water, alcohols or alkalis,.



EVERNIC ACID. 435



When erythrin is dissolved in milk of lime it decomposes in the
course of a day or two with formation of picroerythrin, which is
also obtained pure when erythrin is boiled for some hours with
amyl alcohol. It crystallizes in silky prisms, which readily
effloresce, melt at 158 and have a slightly sweet and intensely
bitter taste. It is exceptionally soluble in hot water and under-
goes no change when boiled with absolute alcohol. Ferric
chloride produces a purple-violet colouration.

2233 In connection with these compounds, the following,
which are to some extent homologous with them, may be
mentioned here.

Evernic acid, C 17 H 16 7 . According to Rochleder and Heldt,
lecanoric acid occurs in Evcrnia Prunaslri ; Stenhouse, how-
ever, could not detect it in lichens grown in Scotland, but found
in them evernic acid, together with usnic acid, C 18 H 18 7 , thus
proving either that the German and Scotch lichens contain
different compounds, or, what is much more probable, that the
German chemists had not investigated the true Evernia Pru-
nastri, 1 a view which is supported by the fact that Hesse, who
examined this lichen collected in various parts of Germany,
always found evernic acid in it. 2

It is almost insoluble in water, but dissolves easily in alcohol, and
crystallizes in spherical aggregates of needles, which melt at 164.

Ewrninic acid, C 9 H 10 O 4 , is formed, together with carbon
dioxide and orcinol, when evernic acid is boiled with lime water
or baryta water. It is tolerably soluble in hot water, readily in
alcohol, and crystallizes in flat, lustrous needles, resembling
those of benzoic acid. It melts at 159, and on further heating
emits a penetrating odour and yields a colourless sublimate.
Ferric chloride colours the aqueous solution violet.

Barlalic acid, C 19 H 20 O 7 . This substance, which stands in
the same relation to homorcinol (p. 402) as evernic acid to
orcinol, occurs with usnic acid in Usnea barbata. It crystallizes
from benzene in long plates, needles, or short prisms, which
melt at 168, and decompose at a higher temperature with
evolution of carbon dioxide and formation of homorcinol. 3

IB- Erythrin or Homo-cry thrin, C. 21 H 24 O 10 -f-H 2 0, was discovered
in a stunted specimen of E. fuciformis. 4 ' It crystallizes in

1 Ann. CJicm. Pharm. Ixviii. 83 ; civ. 56. 3 !*** cxvii. 297.

3 Stenhouse and Groves, Journ. Chcm. Soc. 1880, 407.

4 Menschutkin, Bull. Soc. Chim, [2] ii. 424 ; Lamparter, Ann. Chcm. FUi
cxxxiv. 234.

F F 2



436 AROMATIC COMPOUNDS.

concentrically arranged needles, which are very readily soluble in
alcohol. On boiling with baryta water it is resolved into carbon
dioxide, erythrol and homorcinol :

C 13 H 1C 6 + 2H 2 = C0 ? + C 4 H 10 4 + C 8 H 10 O 2 .

It is not homologous with picroerythrin, but is the anhydride
of such a compound, which would probably have the following
constitution :

/CO.O X
(CH 3 ) 2 C 6 H(OH)/ >C 4 H 6 (OH) 2 .



Picrorocellin, CgyHggNgOg, was found along with erythrin by
Stenhouse and Groves in a variety of R. tinctoria which pro-
bably came from western Africa. It is insoluble in water,
tolerably soluble in hot alcohol, and crystallizes in long, lus-
trous prisms, which melt at 192 194, and have an intensely
bitter taste. On oxidation with chromic acid, benzoic acid is
obtained together with a liquid smelling like benzaldehyde.
On dry distillation it yields water, ammonia, and xanthovocellin,
C Q1 H 1V N 2 O 2 , which is also obtained by heating picrorocellin with
dilute acids, and crystallizes from alcohol in long, yellow needles,
melting at 183 . 1

2234 Para-orsellinic acid, C 6 H 2 (CH 3 )(OH) 2 C0 2 H + H 2 0, is
prepared by heating orcinol with 4 parts of ammonium car-
bonate and 4 parts of water for 10 15 hours to the boiling-
point of amyl alcohol, 2 or by passing carbon dioxide over the
potassium compound of orcinol at 250 260. 3 It crystallizes
from dilute alcohol in fine, hard needles, which dissolve in
about 660 parts of cold water ; the solution is coloured blue by
ferric chloride. On heating the acid it loses water at 100 and
commences to melt at about 150 with evolution of carbon
dioxide, which is also given off when the acid is simply boiled
with water; on dry distillation it decomposes completely with
formation of orcinol.

Barium para-orsellinate, (C 8 H 7 O 4 ) 2 Ba + 6H 2 O, crystallizes in
four -sided tablets, which are readily soluble in water.

ParapJwsphorsellinic acid is formed as a chromegreen powder
by heating para-orsellinic acid with phosphorus oxychloride
(p. 433). ^

1 Ann. Cliem. Pharm. clxxxv. 14.

2 Brunner and Senhofer, Monatsh. i. 236.

3 Schwarz, Ber. Deutsch. Chem. Gcs. xiii. 1C43,



CRESORSELLINIC ACID. 437

Crcsorcinolcarboxylic acid, C 6 H 2 (CH 3 )(OH) 2 CO 2 H + H 2 O, is
formed when cresorcinol is heated in a small flask with 4 parts
of potassium or sodium bicarbonate for half an hour. It is
slightly soluble in cold, readily in hot water and alcohol, and
crystallizes in very long, thin, lustrous prisms, which lose their
water at 100 and melt at 208 with decomposition. Its solution
is coloured bluish violet by ferric chloride and is not precipitated
by lead acetate. 1

Cresorsellinic acid, C 6 H 2 (CH 3 )(OH) 2 C0 2 H (1 : 2:4:6), is pre-
pared by fusing disulphorthotoluic acid with caustic potash. It
is slightly soluble in cold, readily in hot water, and crystallizes in
long, hard, vitreous needles, which melt at 245. It reduces
ammoniacal silver solution on heating and Fehling's solution on
boiling ; its aqueous solution is coloured dark brown by ferric salts,
a ferrous compound being formed. On heating with sulphuric
acid the liquid assumes a splendid stable magenta colour ; water
precipitates from it yellow flocks, which form an intense golden-
yellow solution in alkalis. It therefore gives a similar reaction
to that which is characteristic of the analogous a-resorcylic acid
(p. 358). When it is heated to 220 225 with hydrochloric
acid, dark flocks separate out, which form a reddish brown
solution in alcohol ; on the addition of a little alkali, the liquid
takes a splendid dark green fluorescence, which disappears when
an excess of alkali is added, a deep purple-red solution being
formed. Cresorcinol is formed when the acid is distilled with
slaked lime. 2

Three carboxylic acids are derived from cresorcinol :

C0 2 H C0 2 H C0 2 H



\

OH'OH
OH

The last of these expresses the constitution of cresorsellinic
acid, which is a derivative of orthotoluic acid. The second
probably represents that of cresorcinolcarboxylic acid, since the
readiness with which it is formed supports the conclusion that
the carboxyl takes up the same position in the nucleus in the
case of cresorcinol as it does in the analogous formation of
/3-resorcylic acid from resorcinol (p. 359).

1 Kostanccki, Ber. Dcutsch. Chem. Gcs. xviii. 3202.
3 Jacobsen and Wierss, ibid. xvi. 1956.



438 AROMATIC COMPOUNDS.



The constitution of para-orsellinic acid, and therefore that of
orsellinic acid, follows from these considerations (Kostanecki) :

Orsellinic acid. Para-ovsellinic acid.

C0 H C0 2 H



OH X ^OH CH

\/ \x

CH 3 OH.

2235 Homohydroxysalicylic acid, C 6 H 2 (CH 3 )(OH) 2 C0 2 H, is
prepared by heating 40 grms. of toluquinol for thirty-six hours
in a bath of oil of turpentine with 130 grms. of potassium
bicarbonate, 110 ccs. of water, and 40 ccs. of a saturated
solution of potassium sulphite. It dissolves in 1,366 parts of
water at 8, more readily in hot water, and crystallizes from
dilute alcohol in microscopic, acute rhombic plates, while, when
prepared from the ammoniacal salt by precipitation with hydro-
chloric acid, it separates as a crystalline powder containing half
a molecule of water. Ferric chloride produces an azure-blue
colouration, which passes into a beautiful green on standing
or on the addition of an excess of the chloride ; it reduces
Fehling's solution on warming, but a neutral silver solution in
the cold. It is decomposed at 210 220 into carbon dioxide
and toluquinol. 1

Barium Jiomohydroxysalicylate, (C 8 H 7 O 4 ).,Ba + 2H 2 O, forms
fine prismatic needles, readily soluble in water.

Creosolcarloxylwacid, C 6 H 2 (CH 3 )(OCH 3 )(OH)CO 2 H (1:3:4:5).
-According to the researches of Kostanecki, only those phenols
which contain hydroxyl groups in the meta-position are con-
verted into carboxylic acids by boiling with the alkali bicar-
bonates, and as creosol does not belong to this class of bodies,
the corresponding acid is prepared by adding sodium, warming
gently and passing in a current of carbon dioxide.

Creosolcarboxylic acid crystallizes from a mixture of chloroform
and benzene in concentrically arranged needles, which melt at
180 182 and sublime when carefully heated. It is readily
soluble in alcohol, ether and chloroform, but only slightly in
water and scarcely at all in benzene and petroleum ether ; its
solution is coloured deep blue by ferric chloride. The barium
salt crystallizes in small, anhydrous needles, which are only
slightly soluble in water.

1 Brimner, Monatsh, Chein. ii. 458,



XYLYLENE ALCOHOLS.



Methyl creosolcarboxylate, C 6 H 4 (CH 8 )(OCH 3 )(OH)CO 2 .CH 3 ,
forms small, rhombic prisms, melts at 92 and gives a bluish
<*reen colouration with ferric chloride. 1



/CH 2 .OH
XYLYLENE ALCOHOLS, C 6 H.<

\CH 2 .OH

2236 Orthoxylylene alcohol was first prepared by the action of
sodium amalgam on a boiling solution of phthalyl chloride,
C 6 H 4 .C 2 2 C1 2 (p. 458), in glacial acetic acid, and named phthal-
alcohol. 2 It is also obtained by boiling its bromide with a solution
of sodium carbonate 3 or potassium carbonate. 4 It is tolerably
soluble in water, readily in alcohol, and crystallizes in rhombic
tablets, which have a bitter taste and melt at G4'5. Concentrated
sulphuric acid imparts to them a red colour and then converts them
into a resinous mass. Potassium permanganate or chromic acid
oxidize it to phthalic acid, while it is reduced to orthoxylene by
heating with hydriodic acid and amorphous phosphorus.

Orthoxylylene ethyl ether, C 6 H 4 (CH 2 OC 2 H 5 ) 2 , is obtained by
boiling the bromide with alcoholic potash, and is a very pleasant-
smelling, oily liquid, which boils at 247 249 (Leser).

Orthoxylylene chloride, C 6 H 4 (CH 2 C1) 2 , is formed when ten
ccs. of orthoxylene are heated to 190 with 35 grms. of phos-
phorus pentachloride, 5 as well as by heating the alcohol with
hydrochloric acid, and separates from ether in crystals, which
melt at 54'8 and readily sublime. Its vapour attacks the eyes
with great violence.

Raymann, by the action of chlorine on boiling orthoxylene,
obtained an isomeric substance, which crystallizes in tablets and
melts at 103 . 6 These properties correspond with those of
paraxylylene chloride, and the hydrocarbon employed by Ray-
mann must have contained paraxylene, which is much more readily
attacked by chlorine and bromine than its isomerides. This
property can be made use of to detect even traces of paraxylene
in the presence of the ortho- and meta- compounds; the

1 Woiule, Her. Deutsch. Chcm. Ges. xix. 2324. 8 Hessert, ibid. xii. 642.

3 Baeyer and Perkin, xvii. 122.

4 Colson, .47m. Cfiim. Ph],s. [6] vi. 104.

6 Colson and Gautier, Bull. Soc. Chim. xlv. 6 ; Colsoii, Ann. Chim. /'/'.</< [
vi. 108.
6 Bull. Soc. Chim. xxvi. 553.



440 AROMATIC COMPOUNDS.

mixture is treated at the boiling point with sufficient bromine
to form the monobromo-derivatives ; any paraxylene present is
converted into paraxylylene bromide, which separates out on
cooling. 1

Orthoxylylene bromide, C 6 H 4 (CH 2 Br) 2 is obtained when or-
thoxylene is heated with the calculated quantity of bromine to
150 155, or when the latter is allowed to drop into the boil-
ing hydrocarbon, the temperature being gradually raised to 180.
It is also formed when orthoxylene is treated with bromine in the
sunlight, 2 and crystallizes from chloroform in splendid, rhombic
pyramids, which melt at 94'9, and dissolve in 5 parts of
ether.

Orthoxylylene iodide, C 6 H 4 (CH 2 I) 2 , is prepared by heating the
alcohol with phosphorus and hydriodic acid, and crystallizes
from ether in splendid, well-formed yellowish prisms, melting at
109 110. 3

Orthoxylylene acetate, C 6 H 4 (CH 2 O.CO.CH 3 ) 2 , is formed by the
action of acetyl chloride on the alcohol ; it is a crystalline mass,
which melts at 37 and boils without decomposition.

xCH 2 v

Orthoxylylene sulphide, C 6 H 4 <( )S, is obtained by heating

\CH/

the bromide with an alcoholic solution of potassium sulphide,
and is a colourless liquid which smells like mercaptan and
solidifies in large crystals at about (Leser).

Diphenylorthoxylylenediamine, C 6 H 4 (CH 2 .NH.C 6 H 5 ). 2 , is pre-
pared by the action of aniline on the bromide. It crystallizes
from alcohol in small plates, melting at 172, and dissolves in
concentrated hydrochloric acid, but is reprecipitated by water.

Metaxylylene alcohol, C 6 H 4 (CH 2 .OH) 2 . This compound, which
is also known as isophthalalcohol, is prepared by heating the
bromide with a solution of carbonate of potassium. It is readily
soluble in water and separates from ether as an oily liquid,
which solidifies to microscopic, twinned crystals, melting at
46 47. 4

Metaxylylene ethyl ether is obtained by heating the bromide
with alcoholic potash, and is an oily liquid, which boils at
247 249, and is oxidized by chromic acid to isophthalic acid. 5

Radziszewski and Wispek, Bcr. Dcutsch. Chem. Ges. xviii. 1279.

Schramm, ibid, xviii. 1272.

Leser, ibid. xvii. 1824.

Colson, Ann. (Jhim. Phys. [6] vi. 109.

W. H. Perkin, jun., Private communication.



METAXYLYLENE CHLORIDE. 441

Meiaxylylene chloride, C 6 H 4 (CH 2 C1) 2 , is prepared by heating



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