Rudolph August Witthaus.

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The relations of the oxyamin bases are shown in the following
formulae :

CH 3 CH 2 OH CH 3 CH 2 OH

CH 2 CH 2 CHOH CHOH

N N N N

(CH 3 ) 3 OH (CH 3 ) 3 OH (CH 3 ) 3 OH (CH 3 ) 3 OH

Ethyl-trimethyl Cholin. Isocholin. Muscarin.

ammonium (Amanitin).

hydroxid



COH COOH COO, CH 2



CH 2



CH 2 CH 2 CH

. A

& \ & \ & # \

(CH 3 ) 3 OH (CH 3 ) 3 C1 (CH 3 ) 3 (CH 3 ) 3 OH

Betain Betain Betain. Neurin.
aldehyde. hydrochlomd.




NITROGEN DERIVATIVES OF THE PARAFFINS 333

Among the diamins are included several of the alkaloidal products
of putrefaction known as ptomains.

Ethylenediamin H 2 N.(CH 2 )2.NH2 is a strongly alkaline liquid,
boiling at 116.5 (241.7 F.). With acetyl chlorid it forms diacetyl-

CH 2 .NH.CO.CH 3
ethylene diamin, I , which is decomposed by heat with

CH 2 .NH.CO.CH 3
formation of a cyclic amidin base (p. 334), ethylene-ethenyl amidin,

CH 2 .NH\
or lysidin, I ^C.CHa, a crystalline solid, fusing at 105 (221

CH2-N

F.), which is also prepared by heating ethylenediammonium chlorid
with sodium acetate, and has been used as a solvent for uric acid.

Trimethylenediamin H 2 N.(CH2)3.NH2 is said to have been
obtained from the cultures of the comma bacillus. It has been ob-
tained synthetically by the second method given on p. 330. It is an
alkaline liquid, boiling at 135 (275 F.).

Tetramethylenediamin Putrescin H 2 N. (CH^.NEk is pro-
duced, along with the cadaverin, during the putrefaction of muscular
tissue, internal organs of man and animals, arid of fish, and in the
culture media of the comma bacillus from three days to four months.
The free base is a colorless liquid (solid below 27) having a seminal
odor, which absorbs C02 from the air and unites with acids to form
crystalline salts. It is not activelv poisonous.

Pentamethylenediamin Cadaverin H^N. (CKbh .NH2 is iso-
meric with neuridin and is produced during the later stages of putre-
faction of many animal tissues, the cholin disappearing as this and
the other diamins are formed. The free base is a clear syrupy liquid,
having a strong disagreeable odor, resembling that of conim, boils at
175, and fumes in air. It absorbs C(>2 rapidly, with formation of a
crystalline carbonate. Its salts are crystalline. The chlorid on dry
distillation is decomposed into ammonium chlorid and piperidin
(p. 461).

Hexamethylenediamin H2N.(CH2)e.NH2 is formed during pu-
trefaction of muscular tissue and pancreas. It is a crystalline solid,
fusing at 40 (104 F.) and boiling at 195 (383 F.).

Neuridin C5HuN2 a diamin of undetermined constitution, iso-
meric with cadaverin, is produced, along with cholin (p. 330), during
the earlier stages of putrefaction, particularly of gelatinoid sub-
stances, and increases in quantity as putrefaction advances, while the
quantity of cholin diminishes. The free base is a gelatinous sub-
stance, having a very marked seminal odor, readily soluble in
water, insoluble in alcohol and in ether. Its chlorid is crystalline
and very soluble in water. It seems to be non- poisonous when
pure.

Saprin C4HieN2 another diamin of undetermined constitution.



334 MANUAL OF CHEMISTRY

has been obtained from putrid spleens and livers after three weeks'
putrefaction.

Mydalein is still another putrid product of undetermined compo-
sition, but probably a diamin containing four or five carbon atoms,
which forms a difficultly crystallizable, hygroscopic chlorid, which is
actively poisonous. Five milligrams administered hypodermically to
a cat causes death after profuse diarrhoea and secretion of saliva, vio-
lent convulsions and paralysis, beginning with the extremities and

extending to the muscles of respiration.

CH 2v
Spermin C2H5N probably ethylene-imin, I /NH, has been

CH2

obtained from semen, testicles, ovaries, prostate, thyroid, pancreas,
and spleen. Its phosphate forms crystals, known as Leyden,
Bottcher's, or Charcot's crystals, which are met with in anatomical
preparations preserved in alcohol, in dried semen, in sputa and nasal
secretions, in the blood, spleen, and other organs of Ieucocytha3mics
and ana3mics, and in fa3ces. A substance, probably identical with
spermin, is also found in the cultures of the comma bacillus on beef-
broth. The free base forms crystals, which rapidly absorb carbon
dioxid from air, are readily soluble in water and in alcohol, insoluble
in ether, and strongly alkaline in reaction. The Charcot crystals are
insoluble in alcohol, ether and chloroform, difficultly soluble in water,
easily soluble in dilute acids or alkalies.

The imins, also called imids (but see p. 347), are formed by the
substitution of bivalent hydrocarbon groups for two hydrogen atoms
in a single molecule of ammonia; the diimins, also called diamids, by
the substitution of two such groups for four hydrogen atoms in two
molecules of ammonia. These compounds are cyclic, and include
some important members of the aromatic series.

When the diammonium chlorids are heated ammonium chlorid is
split off, and an imin or a diimin is formed. Thus piperidin (p. 461)
is produced from pentamethylene diamin ; and piperazin (p. 462)
from ethylene diamin :



AMIDINS AMIDOXIMS HYDROXAMIC ACIDS .

The amidins contain both the amido group, NH 2 , and the imido
group, NH, and have the general formula: R-C^H 2 ' m which R is
any univalent hydrocarbon radical.



NITROGEN DERIVATIVES OF THE PARAFFINS 335

They are formed by heating the nitrils (p. 340) with ammonium
chlorid. Thus acetonitril yields acetamidin : CHa.CiN+NEUCl^

HCl-f CH 3 .C<^H 2 - They are also formed by action of HC1 upon the
amids. Indeed, they may be considered as being derived from the
amids (p. 345) by substitution of NH for the carbonyl oxygen :

CH 3 .C^o H2 acetamid : CH 3 .C^1 2 ' acetamidin. The amidins are
monacid bases, very unstable when free.

The amidoxims are derived from the amidins by substitution of
OH for hydrogen, e.g., CH 3 .C^ N O 2 H , ethenylamidoxim. They are

very unstable compounds, formed by the action of hydroxylamin
upon nitrils or upon amidins (p. 360).

Hydroxamic acids contain the oxim group, N.OH, while the
amido group of the amidin is replaced by hydroxyl :
acetohydroxamic acid.



GUANIDIN AND ITS DERIVATIVES.

Guanidin Carbotriamin CH 5 N 3 was first obtained by oxidation
of guanin (p. 357). Its synthesis has been accomplished by heating
together ethyl orthocarbonate, C(OC2Hs)4, and NH 3 . It is a crystal-
line substance, which absorbs C(>2 and EbO from the air, and forms
crystalline salts. Some of its derivatives are important physio-
logically.

/NTT

Guanidin, containing the group .C^ NH 2 , is an amidin. It may also
be considered as a triamin, derived from three ammonia molecules,

/NTT

H2N C<^ NH 2 . It is related to amidocarbonic acid, to urea and to
pseudourea, as is indicated by the formulae:

NH _ C /NH 2 _ C /NH 2 NH _ C /NH 2 Q _ r /NH 2
C \NH 2 \NH 2 C \OH C \OH

Guanidin. Urea. Pseudourea. Amido carbonic

acid.

Methyl-guanidin Methyluramin HN : C(NH 2 ) NH ( CH 3 ) was
first obtained by the oxidation of creatin and of creatinin (see below).
It has also been obtained as a product of putrefaction of mus-
cular tissue at a low temperature in closed vessels, when it probably
results from the decomposition of creatin. It is a colorless,
crystalline, deliquescent, strongly alkaline substance, and is highly
poisonous.

The relation of guanidin and methyl -guanidin to each other and
to creatin and creatinin is shown by the following formulas :



336 MANUAL OF CHEMISTRY



'\N(CH 3 ).CH 2 .COOH
Guanidin. Creatin.

TTXT r 1 / NH 2 yNH CO

L \NH(CH 3 ) HN=C<

X N(CH 3 )CH 2
Methyl-guanidin. Creatinin.



Creatin Methyl-guanidin acetic acid C4H9N302+Aq is, as is
shown by the above graphic formula, a complex amido-acid (p. 361).
It is a normal constituent of the juices of muscular tissue, brain,
blood, and amniotic fluid. It is formed synthetically by the union
of methyl glycocoll (p. 363), and cyanamid (p. 344) : CH 2 (NH.CH 3 ).-



It is best obtained from the flesh of the fowl, which contains 0.32
per cent., or from beef -heart, which contains 0.14 per cent. It is
soluble in boiling E^O and in alcohol, insoluble in ether; crystallizes
in brilliant, oblique, rhombic prisms; neutral; tasteless; loses Aq at
100 (212 F.) ; fuses and decomposes at higher temperatures. When
long heated with H2O, or treated with concentrated acids, it loses
IkO, and is converted into creatinin. Baryta water decomposes it
into sarcosin and urea. It is not precipitated by silver nitrate, ex-
cept when it is in excess and in presence of a small quantity of po-
tassium hydroxid. The white precipitate so obtained is soluble in
excess of potash, from which a jelly separates, which turns black,
slowly at ordinary temperatures, rapidly at 100 (212 F.). A white
precipitate, which turns black when heated, it also formed when a
solution of creatin is similarly treated with mercuric chlorid and
potash.

Creatinin Methyl guanidin acetic lactam C^yNsO 113 a
product of the dehydration of creatin, is a normal and constant con-
stituent of the urine and amniotic fluid, and also exists in the blood
and muscular tissue.

It crystallizes in oblique, rhombic prisms, soluble in H 2 O and in
hot alcohol, insoluble in ether. It is a strong base, has an alkaline
taste and reaction; expels NHa from the ammoniacal salts, and forms
well-defined salts, among which is the double chlorid of zinc and
creatinin (C^NaOhZnC^, obtained in very sparingly soluble,
oblique prismatic crystals, when alcoholic solutions of creatinin and
zinc chlorid are mixed.

Ly satin CeHisNsC^, or Lysatinin CeHnNaO-hH^O one of the
hexon bases, formed in the decomposition of protein bodies, is a
superior homologue of creatin or of creatinin.

Cruso-creatinin CsHgN^ is an orange -yellow, crystalline solid,
alkaline in reaction ; Xantho-creatinin CsHw^O is in yellow crys-



NITROGEN DERIVATIVES OF THE PARAFFINS 337



talline plates; Amphi-creatinin CgHigNTC^ forms yellowish -white
prismatic crystals. These are basic substances, forming crystalline
chlorids, and belonging to the class of leucomains, which include
alkaloidal substances produced by physiological processes. (See p.
496). They are obtained from the juices of muscular tissue, and
from Liebig's meat extract, in which they accompany creatin and
creatinin.

HYDBAZINS.

The hydrazins are derivatives of the hypothetical diamidogen,
H2N.NH2 (p. 105), by substitution of aliphatic or aromatic radicals,
alcoholic, phenolic or acid, for one or more of the hydrogen atoms
in the same way as the amins are derived from ammonia. There are,
therefore, primary, secondary, tertiary and quarternary hydrazins;
and they may be symmetrical, as C2Hs.HN.NH.C2H5 and CeHs.-
HN.NH.C 2 H 5 , or unsymmetrical, as C 6 H 5 .HN.NH 2 and (CfcHa)sN.-
NH2. The aliphatic hydrazins are obtained from the alky 1- ureas,
by conversion into nitroso- amins, and reduction. Most of the hydra-
zins, some of which are of considerable interest, are derivatives of
phenyl-hydrazin, C 6 H 5 .HN.NH 2 , and, containing a cyclic chain C6H 5 ,
will be considered among the aromatic compounds.



NITRILS AZOPARAFFINS CYANOGEN COMPOUNDS .

These substances may be considered either as compounds of the
univalent radical cyanogen (C iv N'")'; or as paraffins, C n H 2 n+ 2 , in
which three atoms of hydrogen have been replaced by the trivalent
N'" atom, hence azoparaffins ; or as nitrils, compounds of N with
the trivalent radicals C n H 2 n-i.

Hydrogen Cyanid Formonitril Cyanogen hydrid Hydrocyanic
acid Prussic acid HCIN exists ready formed in the juice of
cassava, and is formed by the action of H2O upon bitter almonds,
cherry-laurel leaves, and other vegetable products containing amyg-
dalin, a glucosid, which is decomposed into glucose, benzoic aldehyde
(p. 410), and hydrocyanic acid, when warmed with water. It is also
formed in a great number of reactions: by the passage of the
electric discharge through a mixture of acetylene and nitrogen:
HC:CH + N 2 =2HC:N; by the action of chloroform on ammonia:
NH 3 + CHC1 3 = 3HC1 + HCN; by the distillation of, or the action of
HNOa upon, many organic substances; by the decomposition of
cyanids (see Nitrils, below).

It is always prepared by the decomposition of a cyanid or a
ferrocyanid, usually by acting upon potassium ferrocyanid with
22



338 MANUAL OF CHEMISTRY

dilute sulfuric acid, and distilling. Its preparation in the pure
form is an operation attended with the most serious danger, and
should only be attempted by those well trained in chemical manip-
ulation. For medical uses a very dilute acid is required; the acid,
hydrocyanicum dil. (U. S. Br.) contains, if freshly and properly
prepared, two per cent, of anhydrous acid. That of the French
Codex is much stronger ten per cent.

The pure acid is a colorless, mobile liquid, has a penetrating and
characteristic odor; sp. gr. 0.7058 at 7 (44.6 F.); crystallizes at
-15 (5 F.) ; boils at 26.5 (79.7 F.); is rapidly decomposed by
exposure to light. The dilute acid of the U. S. P. is a colorless
liquid, having the odor of the acid; faintly acid, the reddened litmus
returning to blue on exposure to air; sp. gr. 0.997; 10 grams of
the acid should react without excess with 1.27 gram of silver nitrate.
The dilute acid deteriorates on exposure to light, although more
slowly than the concentrated; a trace of phosphoric acid added to
the solution retards the decomposition.

Most strong acids decompose HCN. The alkalies enter into double
decomposition with it to form cyanids. It is decomposed by Cl and
Br, with formation of cyanogen chlorid or bromid. Nascent H con-
verts it into methylamin.

Analytical Characters. (1) With silver nitrate: a dense, white
ppt.; which is not dissolved on addition of HNOs to the liquid, but
dissolves when separated and heated with concentrated HNOs; solu-
ble in solutions of alkaline cyanids or thiosulfates. (2) Treated
with NHtHS, evaporated to dry ness, and ferric chlorid added to the
residue: a blood-red color, which is discharged by mercuric chlorid.
(3) With potash and then a mixture of ferrous and ferric sulfates:
a greenish ppt., which is partly dissolved by HC1, leaving a pure
dark -blue precipitate. (4) Heated with a dilute solution of picric
acid and then cooled : a deep -red color. (5) Moisten a piece of
filter- paper with a freshly prepared alcoholic solution of guaiac; dip
the paper into a very dilute solution of CuSO4, and, after drying,
into the liquid to be tested. In the presence of HCN it assumes a
deep -blue color. (6) Add a few drops of potassium nitrite solution,
then two or three drops of ferric chlorid solution, and enough dilute
H2SO4 to turn the color to yellow. Heat just to boiling; cool, add
a few drops of NHtHO, filter, and add to the filtrate a few drops
of dilute, colorless ammonium sulf hydrate: a violet color, changing
to blue, then to green and yellow (p. 345).

Toxicology. Hydrocyanic acid is a violent poison, whether it be
inhaled as vapor, or swallowed, either in the form of dilute acid, of
soluble cyanid, or of the pharmaceutical preparations containing it,
such as oil of bitter almonds and cherry-laurel water; its action being



NITROGEN DERIVATIVES OF THE PARAFFINS 339

more rapid when taken by inhalation or in aqueous solution than in
other forms. When the medicinal acid is taken in poisonous dose,
its lethal effect may seem to be produced instantaneously; nevertheless,
several respiratory efforts usually are made after the victim seems to
be dead, and instances are not wanting in which there was time for
considerable voluntary motion between the time of ingestion of the
poison and unconsciousness. In the great majority of cases the
patient is either dead or fully under the influence of the poison on
the arrival of the physician, who should, however, not neglect to
apply the proper remedies if the faintest spark of life remain.
Chemical antidotes are, owing to the rapidity of action of the poison,
of no avail, although possibly chlorin, recommended as an antidote
by many, may have a chemical action on that portion of the acid
already absorbed. The treatment indicated is directed to the main-
tenance of respiration; cold douche, galvanism, artificial respiration,
until elimination has removed the poison. If the patient survive
an hour after taking the poison, the prognosis becomes very favor-
able; in the first stages it is exceedingly unfavorable, unless the
quantity taken has been very small.

In cases of death from hydrocyanic acid the odor of the poison
may be observed in the apartment, or upon opening the body. In
cases of suicide or accident, the vessel from which the poison has
been taken will usually be found in close proximity to the body,
although the absence of such vessel is not proof that the case is
necessarily one of homicide.

Notwithstanding the volatility and instability of the poison, its
presence has been detected two months after death, although the
chances of separating it are certainly the better the sooner after
death the analysis is made. The search for hydrocyanic acid is
combined with that of phosphorus; the part of the distillate con-
taining the more volatile products is examined by the tests given
above. It is best, when the presence of free hydrocyanic acid is
suspected, to distil at first without acidulating. In cases of sus-
pected homicide by hydrocyanic acid, the stomach should never be
opened until immediately before the analysis.

Cyanogen Chlorids. Two polymeric chlorids are known: Cyano-
gen chlorid, CNC1, formed by the action of Cl upon anhydrous HCN
or upon Hg(CN) 2 in the dark. It is a colorless gas, condensing
to a liquid at 15 (59 F.); intensely irritating and poisonous.
Tricyanogen chlorid, C 3 N 3 Cl3, is formed, as a crystalline solid, when
anhydrous HCN is acted upon by Cl in sunlight. It fuses at 146
(294.8 F.).

Cyanids. The most important of the simple metallic cyanids are
those of K and Ag (pp. 181, 184, also p. 344).



340 MANUAL OF CHEMISTRY

Nitrils. The hydrocyanic esters of the univalent alcoholic rad-
icals are called acid nitrils, because of their formation from the
amids (p. 345), by the reaction given under (3) below. Hydro-
cyanic acid, being produced from formamid, is formonitril; methyl
cyanid, derived from acetamid, is acetonitril, etc. They are also
derivable from the ammonium salt of the acid by elimination of the
elements of two molecules of water. Their formula may be derived
from those of the acids by substitution of N for the trivalent OOH
of the carboxyl.

The nitrils are produced: (1) By heating the haloid esters (p.
233) with alcoholic solution of potassium cyanid at 100: CH 3 .CH 2 I-
+KCN = CH 3 .CH 2 .CJSH-KI. (2) By distilling a mixture of potas-
sium cyanid and the potassium salt of a monoalkyl sulfate. Thus,
ethyl cyanid is produced from potassium ethylsulf ate : KCN+SO4.-
C 2 H 5 .K = K 2 SO4+C 2 H 5 .CN. (3) By complete dehydration, by the
action of P 2 O5, of the ammoniacal salt of the acid, or of its amid
(p. 346). Thus acetonitril is obtained from ammonium acetate:
CH 3 .COO(NH 4 )=CH 3 .CN-f 2H 2 O; or from acetamid: CH 3 .CO.NH 2 -
=CH 3 .CN+H 2 0. (4) By the action of acidyl chlorids upon silver
cyanate. Thus, with acetyl chlorid, methyl cyanid is formed :
CNOAg-hCH 3 .CO.Cl = AffCl+COH-CHg.CN.

The nitrils combine with nascent hydrogen to form primary
amins. Thus acetonitril forms ethylamin: CH 3 .CN+2H 2 =C 2 H 5 .NH 2 .
Hydrating agents convert them into the ammonium salts of the cor-
responding acids. Thus ammonium propionate is derived from ethyl
cyanid: C 2 H 5 .CN-f 2H 2 O=C 2 H 5 .COO(NH 4 ). Or, when acted upon by
concentrated sulfuric acid, hydrogen peroxid, or concentrated hydro-
chloric acid, they take up one molecule of water and form amids
(p. 346). Thus acetonitril forms acetamid: CH 3 .CN+H 2 O = CH 3 .-
CO.NH 2 .

Methyl Cyanid Acetonitril CH 3 .CN is a colorless liquid,
b. p. 81.6, having an agreeable odor, sparingly soluble in water,
obtained by distilling ammonium acetate or acetamid with P 2 Os.

The isocyanids, carbylamins, or carbamins are isomeres of the
nitrils, which differ from the latter in constitution in that, in the
nitrils, the nitrogen is trivalent, and the alkyl group is in union
with carbon, e.g., methyl cyanid, N=C CH 3 , while in the carbyl-
amins the nitrogen is quinquevalent, and the alkyl is in union with
nitrogen, e. g., methyl isocyanid, C=N CH 3 . The isocyanids, when
acted upon by hydrating agents, do not yield ammonium salts of the
corresponding acids, as do the nitrils (see above), but are decomposed
into formic acid and a primary amin. Thus ethyl isocyanid does not
yield propionic acid, but formic acid and ethylamin : NC.C 2 H5+
2H 2 O=H.COOH-fC 2 H 5 .NH 2 .



NITROGEN DERIVATIVES OF THE PARAFFINS 341

The isocyanids are formed: (1) by the action of a primary mona-
min on chloroform in the presence of caustic potash. Thus methyl
isocyanid is derived from methylamin : CH 3 .NH 2 -f CHC1 3 =3HC1+
NC.CHs. (pp. 235, 328) ; (2) by the action of alkyl iodids upon silver
cyanid: CH 3 I+AgCN=AgI+NC.CH 3 .

Methyl Isocyanid Methyl carbylamin Isoacetonitril CH 3 .NC
is a colorless liquid, b. p., 58, having a disagreeable odor, and giv-
ing off highly poisonous vapor. It is formed by the reactions given
above, and is said to exist in the venom of toads.

Phenyl Isocyanid Isobenzonitril CeHs.NC is a colorless liquid,
not boiling without decomposition, having an intensely disagreeable
odor, whose formation is utilized in a test for chloroform (p. 235).

Both nitrils and isonitrils combine with the hydracids to form
crystalline salts, decomposable by water; the latter much more en-
ergetically than the former. They are all volatile liquids; the nitrils
having ethereal odors when pure, the isonitrils odors which are very
powerful and disagreable.

Nitrils of the Oxyacids. The nitrils of the a- acids of the oxy-
acetic series (p. 290) are also called cyanhydrins, or oxycyanids, and
bear the same relation to the acids, as exists between the acids of the
acetic series and their nitrils :

CH 3 .COOH CH 3 .CN

Acetic acid. Acetonitril.

CH 3 .CHOH.COOH CH 3 .CHOH.CN

a-lactic acid. Lactic nitril.

They are formed as additive products between hydrocyanic acid
and the aldehydes and ketones: HCN+CH 3 .CHO=CH 3 .CHOH.CN,
and HCN+CH 3 .CO.CH 3 =^^>C/gg By hydration they yield the

corresponding acid and ammonia : CH 3 .CHOH.CN-h2H2O= : CH 3 .-
CHOH.COOH+NH 3 . These reactions are utilized in the synthesis
of theoxyacids (p. 290).

Nitrils of the Ketone Acids. These are the cyanids of the
acidyls, as the nitrils are the cyanids of the alkyls, and are formed
by heating the acidyl chlorids with silver cyanid. Thus acetyl cyanid
is produced from acetyl chlorid : CH 3 .CO.Cl-f-AgCN=CH 3 .CO.CN+
AgCl; or by dehydration of the aldoxims (p. 360) of the a-aldehyde
ketones. Thus oximido- acetone yields acetyl cyanid: CH 3 .CO.CH:-
N.OH=CH 3 .CO.CN+H 2 O. They are unstable, and are decomposed
by water into hydrocyanic acid and their corresponding acids: CHa.-
CO.CN+H 2 O=CH 3 .COOH+CNH.

Nitrils of Dicarboxylic Acids. Two nitrils are derivable from a
dicarboxylic acid, one being a nitrilic acid, the other a dinitril. The



342 MANUAL OF CHEMISTRY

nitrilic acid of oxalic acid is only known in its esters ; its dinitril is
dicyanogen :

COOH CO(NH 2 ) COO(C 2 H 5 ) CN

III I

COOH CO(NH 2 ) CN CN

Oxalic acid. Oxamid. Oxalnitrilic Dicyanogen.

ethyl ester.

Dicyanogen CN.CN is prepared by heating mercuric cyanid,
and is also formed by passing an electric arc between carbon points
in an atmosphere of nitrogen.

It is a colorless gas, has a pronounced odor of bitter almonds;
sp. gr., 1.8064 A. It burns in air with a purple flame, giving off N
and C02. It is quite soluble in water, but the solutions soon turn
brown, and then contain ammonium oxalate and formate, urea, and
hydrocyanic acid. The brown color is due to the formation of azul-
mic acid, C 4 H 5 N 5 O.

Succinonitril Ethylene cyanid CN.CH 2 .CH 2 .CN is the dinitril
of succinic acid. It is an amorphous solid, soluble in water, alcohol,
and chloroform. Fuses at 55 (131 F.) .

Nitrils of Carbonic and Thiocarbonic Acids. These constitute
the oxygen and sulfur compounds of cyanogen. Thus cyanic acid
is the nitril of carbonic acid: CO 3 H(NH 4 ) = CONH+2H 2 O, and
thiocyanic acid that of thiocarbonic acid : CO 2 SH(NH4) CSNH+
2H 2 O.

Three structural formula of these compounds are possible: N=C.-
OH, O=O=N.H, and C^N.OH. The first structure is that of the
normal cyanic and thiocyanic acids, the second that of the isocyanates



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