Nitrogen containing
compounds.
Nitrocompounds. Amines.
Diazo- and azocompounds.
Prepared by ass. Medvid I.I.,
ass. Burmas N.I.
Outline
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
Nitroderivates of hydrocarbons.
The methods of extraction of nitroalkanes.
Chemical properties of nitroalkanes.
The aromatic nitrocompounds.
Amines.
Isomery of amines.
Structure and bonding of amines.
Physical properties of amines.
The methods of extraction of amines.
Chemical properties of amines.
Synthetically useful transformations involving aryl diazonium ions.
The medico-biological importance of amines.
Aminoalcohols.
The methods of extraction of aminoalcohols.
Chemical properties of aminoalcohols.
Arylamines.
The methods of extraction of aromatic amines.
Physical properties of aromatic amines
Comparative structure of aromatic and aliphatic amines
Sulphanilic acid
The synthesis of streptocide
Sulphanylamidic preparations
Medicinal preparations (derivates of p-aminobenzoic acid (pABA).
Diazocompounds
The methods of extraction of aromatic diazocompounds
Chemical properties aromatic diazocompounds
Azocompounds
The methods of extraction of aromatic azocompounds.
Chemical properties of aromatic azocompounds
Physical bases of theory of colouration
Azo-dyes.
1. Nitroderivates of hydrocarbons
Nitrocompounds are the derivatives of hydrocarbons which
contain one or several groups –NO2 in their molecule.
Nitroalkanes are poisonous colourless or yellowish liquids
with good smell. They are not dissoluble in water but are
dissoluble in organic solvents. The names of nitrocompound
are formed by adding prefix nitro- to the names of
hydrocarbons. The isomery of nitrocompound is specified by different
structure of carbon chain and different location of group –NO2 in the
molecule.
CH2 NO2
H3C
CH
CH2
CH3
H 3C
CH
CH
NO2 CH3
NO2
2-methyl-3-nitrobutane
2-nitrobutane
NO2
nitrobenzene
CH3
H3C
NO2
3-nitrotoluene
phenylnitromethane
CH2
CH2
1-nitro-2-phenylethane
NO2
2. The methods of extraction of nitroalkanes
1. Nitration of alkanes
CH3−CH3 + HNO3 → CH3−CH2−NO2 + H2O
2. The reaction of halogenalkanes with salts of
HNO2
CH3−CH2−I + NaNO2 → CH3−CH2−NO2 + NaI
3. Oxidation of amines
CH3
CH3
H 3C
C
CH3
NH2
2-methylpropanamine
3[O]
H3C
C
CH3 + H2O
NO2
2-methyl-2-nitropropane
3.Chemical properties of nitroalkanes
Chemical properties of nitroalkanes are specified by the presence of
group –NO2 in the structure of the molecule.
1.
Reaction with HNO2
H3C
CH
NO2 + HNO2
H3C
H
2.
C
N
NO2
+ H2O
OH
Reaction with aldehydes and ketones
H3C H2C
O
CH2 +
C CH3
H
NO2
H OH
H3C H2C
C CH CH3
NO2
-H2O
H3C H2C
C
C CH3
H
NO2
3. Reduction of nitroalkanes. In the result of this reaction
amines form (catalyst is SnCl2)
CH3−CH2−NO2 + 3H2 → CH3−CH2−NH2 + 2H2O
4.The aromatic nitrocompounds
The simplest aromatic nitro compound, having the molecular
formula C6H5NO2.
Nitrobenzene, also known as nitrobenzol or oil of
mirbane, is an organic compound with the chemical formula
C6H5NO2. Nitrobenzene is a water-insoluble oil which
exhibits a pale yellow to yellow-brown coloration in liquid
form (at room temperature and pressure) with an almondlike odor. When frozen, it appears as a greenish-yellow
crystal. Although occasionally used as a flavoring or
perfume additive, nitrobenzene is highly toxic in large
quantities and is mainly produced as a precursor to aniline.
In the laboratory, it is occasionally used as a solvent,
especially for electrophilic reagents.
Properties of nitrobenzene:
1. Production
Nitrobenzene is prepared by nitration of benzene with a mixture of
concentrated sulfuric acid, water, and nitric acid, called "mixed acid." Its
production is one of the most dangerous processes conducted in the
chemical industry because of the exothermicity of the reaction (ΔH =
−117 kJ/mol).
There were four producers of nitrobenzene in the United States in 1991.
2. Mechanism of nitration
The reaction pathway entails formation of an adduct between the Lewis
acidic nitronium ion, NO2+, and benzene. The nitronium ion is
generated in situ via the reaction of nitric acid and an acidic dehydration
agent, typically sulfuric acid:
HNO3 + H+ ⇌ NO2+ + H2O
Zinin’s reaction:
3. Uses
Approximately 95% of nitrobenzene is consumed in the
production of aniline.
4. Specialized applications
More specialized applications include the use of
nitrobenzene as a precursor to rubber chemicals,
pesticides, dyes, explosives, and pharmaceuticals.
Nitrobenzene is also used in shoe and floor polishes,
leather dressings, paint solvents, and other materials to
mask unpleasant odors. Redistilled, as oil of mirbane,
nitrobenzene has been used as an inexpensive perfume for
soaps. A significant merchant market for nitrobenzene is its
use in the production of the analgesic paracetamol (also
known as acetaminophen) (Mannsville 1991). Nitrobenzene
is also used in Kerr cells, as it has an unusually large Kerr
constant.
5. Organic reactions
Aside from its conversion to aniline, nitrobenzene is
readily converted to related derivatives such as
azobenzene, nitrosobenzene, and phenylhydroxylamine.
The nitro- group is deactivating, thus substitution tends
to occur at the meta-position.
6. Safety
Nitrobenzene is highly toxic (TLV 5 mg/m3) and readily
absorbed through the skin.
Although nitrobenzene is not currently known to be a
carcinogen, prolonged exposure may cause serious
damage to the central nervous system, impair vision,
cause liver or kidney damage, anemia and lung irritation.
Inhalation of fumes may induce headache, nausea,
fatigue, dizziness, cyanosis, weakness in the arms and
legs, and in rare cases may be fatal. The oil is readily
absorbed through the skin and may increase heart rate,
cause convulsions or rarely death. Ingestion may
similarly cause headaches, dizziness, nausea, vomiting
and gastrointestinal irritation.
5. Amines
Amines are the derivatives of ammonium. In its molecules atoms of
hydrogen (1,2 or 3) are substituted to atoms of hydrocarbon radicals.
R
N
R
NH2
H
R1
primary amine
secondary amine
R
R1
R2
N
tertiary amine
The names of amines are formed by adding suffix -amine to the names of
hydrocarbon radical.
H3C
H3C
NH2
N
CH2
CH3
H3C
NH
CH2
CH3
N-methylethanamine
NH2
methylamine
H3C
CH
propanamine-2
1
2
3
CH2
CH2
CH3
N
NH
CH3
N-ethyl-N-methylpropanamine-1
diphenylamine
triphenylamine
6. Isomery of amines
Isomery of amines is specified by different structure of
hydrocarbon radicals, different location of aminogroup and
methamery. Methamery is a phenomenon when amines
have the same molecular formula but can be primary,
secondary or tertiary.
CH3
H 2N
CH2CH2CH3
n-propylamine
H 3C
NH CH2CH3
ethylmehylamine
H 3C
N
CH3
trimethylamine
Aniline is the parent IUPAC name for amino-substituted derivatives of
benzene. Substituted derivatives of aniline are numbered beginning at
the carbon that bears the amino group. Substituents are listed in
alphabetical order, and the direction of numbering is governed by the
usual “first point of difference” rule.
Arylamines may also be named as arenamines. Thus, benzenamine is
an alternative, but rarely used, name for aniline. Compounds with two
amino groups are named by adding the suffix -diamine to
the name of the corresponding alkane or arene. The final -e of the parent
hydrocarbon is retained.
Amino groups rank rather low in seniority when the parent compound is
identified for naming purposes. Hydroxyl groups and carbonyl groups
outrank amino groups. In these cases, the amino group is named as a
substituent.
Secondary and tertiary amines are named as N-substituted derivatives of
primary amines. The parent primary amine is taken to be the one with the
longest carbon chain. The prefix N- is added as a locant to identify
substituents on the amino nitrogen as needed.
7. Structure and bonding of amines
Alkylamines: As shown in Figure.1 methylamine, like
ammonia, has a pyramidal arrangement of bonds to
nitrogen. Its H-N-H angles (106°) are slightly smaller than
the tetrahedral value of 109.5°, whereas the C-N-H angle
(112°) is slightly larger. The C-N bond distance of 147 pm
lies between typical C-C bond distances in alkanes
(153 pm) and C-O bond distances in alcohols (143 pm). An
orbital hybridization description of bonding in methylamine
is shown in Figure. 2. Nitrogen and carbon are both sp3hybridized and are joined by a σ bond.
Figure.1 Methylamine

Arylamines: Aniline, like alkylamines, has a pyramidal arrangement
of bonds around nitrogen, but its pyramid is somewhat shallower. One
measure of the extent of this flattening is given by the angle between
the carbon–nitrogen bond and the bisector of the H-N-H angle.
Figure.2
For sp3-hybridized nitrogen, this angle (not the same as the C-N-H
bond angle) is 125°, and the measured angles in simple alkylamines
are close to that. The corresponding angle for sp2 hybridization at
nitrogen with a planar arrangement of bonds, as in amides, for
example, is 180°. The measured value for this angle in aniline is
142.5°, suggesting a hybridization somewhat closer to sp3 than to
sp2.
The corresponding resonance description shows
the delocalization of the nitrogen lone-pair
electrons in terms of contributions from dipolar
structures.
8.Physical properties of amines
We have often seen that the polar nature of a substance can affect
physical properties such as boiling point. This is true for amines, which
are more polar than alkanes but less polar than alcohols. For similarly
constituted compounds, alkylamines have boiling points higher than those
of alkanes but lower than those of alcohols.
Dipole–dipole interactions, especially hydrogen bonding, are present in
amines but absent in alkanes. The less polar nature of amines as
compared with alcohols, however, makes these intermolecular forces
weaker in amines than in alcohols. Among isomeric amines, primary
amines have the highest boiling points, and tertiary amines the lowest.
Primary and secondary amines can participate
in intermolecular hydrogen bonding, but tertiary
amines cannot. Amines that have fewer than six
or seven carbon atoms are soluble in water. All
amines, even tertiary amines, can act as proton
acceptors in hydrogen bonding to water
molecules. The simplest arylamine, aniline, is a
liquid at room temperature and has a boiling
point of 184°C. Almost all other arylamines have
higher boiling points. Aniline is only slightly
soluble in water (3 g/100 mL). Substituted
derivatives of aniline tend to be even less watersoluble.
9. The methods of extraction of amines
Hoffman reaction:
NH3
NH3 + CH3I → [CH3NH3+]I− ↔ CH3NH2 + NH4I
NH3
CH3NH2 + CH3I → [(CH3)2NH2+]I− ↔ (CH3)2NH + NH4I
NH3
(CH3)2NH + CH3I → [(CH3)3NH+]I− ↔ (CH3)3N + NH4I
NH3
(CH3)3N + CH3I → [(CH3)4N+]I−
Gabriele synthesis:
O
O
C
C
- +
NK
+ Cl
N
C2H5
C2H5 + KCl
C
C
O
O
N-ethylphtalimide
potassium phtalimide
O
O
C
C
N
C
O
N-ethylphtalimide
OH
C2H5 + 2H2O
+
C
O
phtalic acid
OH
C2H5
NH2
ethylamine
10. Chemical properties of amines
Nitrosation of arylamines
We learned in the preceding section that different reactions are observed when
the various classes of alkylamines—primary, secondary, and tertiary—react with
nitrosating agents.
Primary arylamines, like primary alkylamines, form diazonium ion
salts on nitrosation. Aryl diazonium ions are considerably more
stable than their alkyl counterparts. Whereas alkyl diazonium ions
decompose under the conditions of their formation, aryl diazonium
salts are stable enough to be stored in aqueous solution at 0–5°C
for reasonable periods of time. Loss of nitrogen from an aryl
diazonium ion generates an unstable aryl cation and is much slower
than loss of nitrogen from an alkyl diazonium ion.
Reaction with acids:
CH3CH2NH2 + HCl → [CH3CH2NH3]+Cl−
Reaction with halogenalkanes:
CH3CH2NH2 + CH3−I → [CH3CH2NH3]+I− → CH3CH2NHCH3 + HI
Reaction with functional derivatives of carboxylic acids. In the result of
these reactions amides form. O
H3C
CH2
NH2 + H3C
C
Cl
H3C
CH2
NH
C
CH3 + HCl
O
Reaction with HNO2
H3C
CH2
NH2 + HO
N
HCl
O
-2H2O
H3C
CH2
+
N Cl-
N
H2O
H3C CH2 OH + N2 + HCl
Isonitrylic reaction
H3C
CH2
NH2 + CHCl3 + 3KOH
C2H5OH
+
H3C
CH2
N
Oxidation
C2H5NH2 + O3 → C2H5NO2 + H2O
C + 3KCl + 3H2O
11. Synthetically useful transformations involving aryl
diazonium ions





12.The medico-biological importance of amines
Methylamine CH3NH2. It is a gas with the smell of
ammonium. Methylamine is used in the production of
medicines, dyes, insecticides and fungicides.
Putrescin NH2CH2CH2CH2CH2NH2
(tetramethylendiamine). It is crystal solid. It is formed
in the process of rotting of corpses. In the human
organism it is used for synthesis of biologically active
polyamines which take part in the biosynthesis of DNA
and RNA.
Cadaverine NH2CH2CH2CH2CH2CH2NH2
(pentamethylendiamine). It is liquid. It is formed in the
process of rotting of corpses like putrescin.
Aniline C6H5NH2. It is colourless liquid with peculiar
smell. It is poisonous. It is used in the process of
synthesis of dyes, medicines, plastic materials.
Phenamine C6H5CH2CH(NH2)CH3 (1phenylpropanamine-2). It is white crystal solid. It is
used as stimulator of CNS.
13. Aminoalcohols
Aminoalcohols are the derivatives of hydrocarbons which contain
aminogroup in their molecule. For aminoalcohols it is used the
nomenclature according to which the location of aminogroup is
denoted by number or Greek letter.
H2C
CH2
OH
NH2
2-aminoethanol or β-aminoethyl alkohol
H 2C
CH2
OH
NH CH3
2-N-methylaminoethanol
Isomery of aminoalcohols is similar to isomery of
disubstituted hydrocarbons.
14. The methods of extraction of aminoalcohols:
1.
Joining of ammonium or amines to α-oxides
H2C
CH2 + NH3
H2C
O
CH2
OH
NH2
2-aminoethanol
2.
Reduction of nitroalcohols
H3C
HC
CH2
OH
3H2
H3C
CH2
OH + H2O
NH2
NO2
3.
HC
Reaction of halogenalcohols with ammonium or
amines
H3C
H2C
Cl
CH2
OH +
H3C
NH
H2C
N
CH2
CH3
OH
+ HCl
CH3
2-N,N-dimethylaminoethanol
15. Chemical properties of aminoalcohols
Chemical properties of aminoalcohols are specified by
the presence of –OH and aminogroups in the structure
of its molecules. Aminoalcohols have basic reaction.
1. Reaction with acids:
H2C
CH2
OH + HCl
H2C
CH2
+ NH3Cl
NH2
H2C
CH2 OH
H2SO4
NH2
H2C
OH
CH2
+ H2O
N
H
2.Reaction with SOCl2:
HO H2C
HO H2C
Cl
H2C
NH + 2SOCl2
Cl
H2C
NH + 2SO2 + 2HCl
16. Arylamines
Arylamines are the derivatives of ammonium. In its
molecule one, two or three hydrogen atoms are
substituted to aromatic radicals. The names of arylamines
depend on the presence of aromatic radicals and their
locations.
NH
diphenylamine
Arylamines: Aniline, like alkylamines, has a pyramidal
arrangement of bonds around nitrogen, but its pyramid is
somewhat shallower. One measure of the extent of this
flattening is given by the angle between the carbon–
nitrogen bond and the bisector of the H-N-H angle.
For sp³-hybridized nitrogen, this angle (not the same as the C-N-H bond
angle) is 125°, and the measured angles in simple alkylamines are close
to that. The corresponding angle for sp² hybridization at nitrogen with a
planar arrangement of bonds, as in amides, for example, is 180°. The
measured value for this angle in aniline is 142.5°, suggesting a
hybridization somewhat closer to sp³ than to sp². The structure of aniline
reflects a compromise between two modes of binding the nitrogen lone
pair (Figure 22.3).
FIGURE 22.3 Electrostatic potential maps of the aniline in which the
geometry at nitrogen is (a) nonplanar and (b) planar.
The electrons are more strongly attracted to nitrogen when
they are in an orbital with some s character—an sp³hybridized orbital, for example— than when they are in a p
orbital. On the other hand, delocalization of these electrons
into the aromatic π system is better achieved if they occupy
a p orbital. A p orbital of nitrogen is better aligned for overlap
with the p orbitals of the benzene ring to forman extended π
system than is an sp³-hybridized orbital. As a result of these
two opposing forces, nitrogen adopts an orbital hybridization
that is between sp³ and sp². The corresponding resonance
description shows the delocalization of the nitrogen lone-pair
electrons in terms of contributions from dipolar structures. In
the nonplanar geometry, the unshared pair occupies an sp³
hybrid orbital of nitrogen. The region of highest electron
density in (a) is associated with nitrogen. In the planar
geometry, nitrogen is sp²-hybridized and the electron pair is
delocalized between a p orbital of nitrogen and the π system
of the ring. The region of highest electron density in (b)
encompasses both the ring and nitrogen.
The actual structure combines features of both; nitrogen adopts a
hybridization state between sp³ and sp².
The orbital and resonance models for bonding in
arylamines are simply alternative ways of describing the
same phenomenon. Delocalization of the nitrogen lone
pair decreases the electron density at nitrogen while
increasing it in the π system of the aromatic ring. We’ve
already seen one chemical consequence of this in the
high level of reactivity of aniline in electrophilic aromatic
substitution reaction. Other ways in which electron
delocalization affects the properties of arylamines are
described in later sections of this chapter.
The derivatives of toluene are called toluidines:
NH2
NH2
NH2
CH2 NH2
NH CH3
CH3
CH3
CH3
о-Толуїдин
o-toluidine
м-Толуїдин
m-toluidine
п-Толуїдин
p-toluidine
Бензиламін
benzylamine
N-Метиланілін
N-methylaniline
17. The methods of extraction of aromatic amines
Recovery of nitroarenes (Zinin reaction)
HCl
C6H5-NO2 + 2Fe + 4H2O
C6H5-NH2 + 2Fe(OH)3
I.
2H, pH= 7
C 6 H 5 -NO 2
-H 2 O
2H
2H
C 6 H 5 -N=O
C 6 H 5 -NH -OH
Nitrozobenzene
N-Phenylhyd
roxilaniline
С6H5-NO2 + 3(NH4)2S
-H 2 O
C 6 H 5 -NH 2
C6H5-NH2 + 2H2O + 6NH3 + 3S
II. Reaction of halogenarenes with ammonium and
amines.
2000C, 0,6-1,0 МПа
C6H5-Cl + 2NH3
-NH4Cl
C6H5-NH2
Cu, t, p
Cl
Cu, t, p
+
H2N
N
H
+ HCl
III. Alkylation of primary aromatic amines
CH3Cl
NH2
CH3Cl
- HCl
+ CH3Cl
N CH3
H
- HCl
N
CH3
CH3
- HCl
18. Physical properties of aromatic amines
Aromatic amines are colourless liquids or solids with peculiar smell.
They can be oxidized by open air very easily. Aromatic amines are
very toxic compounds. Hydrogen bonding significantly influences the
properties of primary and secondary amines. Thus the boiling point of
amines is higher than those of the corresponding phosphines, but
generally lower than those of the corresponding alcohols. Thus
methylamine and ethylamine are gases under standard conditions,
whereas the corresponding methyl alcohol and ethyl alcohols are
liquids. Gaseous amines possess a characteristic ammonia smell,
liquid amines have a distinctive "fishy" smell. Also reflecting their
ability to form hydrogen bonds, most aliphatic amines display some
solubility in water. Solubility decreases with the increase in the
number of carbon atoms. Aliphatic amines display significant
solubility in organic solvents, especially polar organic solvents.
Primary amines react with ketones such as acetone, and most amines
are incompatible with chloroform and carbon tetrachloride. The
aromatic amines, such as aniline, have their lone pair electrons
conjugated into the benzene ring, thus their tendency to engage in
hydrogen bonding is diminished. Their boiling points are high and
their solubility in water low
4.Comparative structure of aromatic and aliphatic
amines.
..
NH2
D
lC-N, нм
СН3
..
NH2
СН2
1,53
3,19
0,127
0,147
:NH2
: NH2



0,00
0,00

19. Chemical properties of aromatic amines
1.
Reaction with acids
..
NH2
2.
+ HCl
+
NH3 Cl
Alkylation
NH2
+ I
NH CH2 CH3
CH2
CH3
+ HI
N-ethylaniline
3. Acylation (reaction with halogenanhydrides or
anhydrides of carbon acids). In the result of this reaction
acylderivatives are formed.
O
C
NH2
HN
CH3
+ (CH3CO)2O
+ CH3COOH
Acylderivatives are used as antipyretic means.
O
O
HO
N
H
парацетамол
paracetomol
C 2H5O
C
CH3
N
H
фенацетин
C
phenacethine
CH3
4. Qualitative reaction to primary aminogroup
+
N
NH2
C
C2H5OH
+ CHCl3 + 3KOH
+ 3KCl
+ 3H2O
The peculiar smell of C6H5CN is felt in the result of this
reaction.
5. Reaction with HNO2. If primary, secondary and tertiary
arylamines react with HNO2 different products can form.
a) primary arylamines
+
NH2
+
N
HNO2
HCl
N
Cl- +
2H2O
b) secondary arylamines
NH
N
+ HNO2
+ H2O
NO
diphenylamine
N-nitrozodiphenylamine
c) tertiary arylamines
N
N
N
+ HNO2
triphenylamine
O
+ H2O
triphenylamine
6. Reaction with aromatic aldehyds - formation azomethans
(Schiff bases) - quality response.
N-benzylidenaniline
7. Halogenation (white precipitate forms).
NH2
NH2
Br
+ 3Br2
Br
H2O
+ 3HBr
Br
8.Nitration reaction - reaction of transmitting, making
protection of amino groups.
NH2
NH-COCH3
(CH3CO)2O
HO-NO2
- CH3COOH
H2O, H+
- CH3COOH
NH-COCH3
NH-COCH3
NO2
+
NH2
NH2
NO2
+
NO2
NO2
NH2
NH2
H2SO4(concentrated), t
+ H2O
+ HNO3(concentrated)
NO2
9. Oxidation
NH2
NH
+ O2
+ H2O
O
hinonimin
NH 2
NO
+ [O]
H2SO5
nitrozobenzene
NH 2
NO2
+ [O]
CF3COOOH
nitrobenzene
10. Reaction with H2SO4
NH
N H
2
conc. H 2 SO
3
t
HSO4
4
-H
N H -S O
N H
2
S O
3H
t
t
-H
3H
2O
2O
H
The product of this reaction is called sulphanilic
acid.
20. Sulphanilic acid
Sulphanilic acid has acidic (-SO3H) and alkaline (NH2) centers in its molecule. Sulphanilic acid is quite
active acid. It easily forms salts with alkalis. But it does
not react with mineral acids. Although it has alkaline (NH2) group it does not have alkaline properties.
Sulphanilic acid is widely used in production of some
medicines and dyes. It is the structural part of a large
group of medicines which have antibacterial action. They
are called sulphanylamides. The basic compound of all
sulphanylamides is streptocide. It is amide of sulphanilic
acid:
H2N
SO2NH2
21. The synthesis of streptocide
The synthesis of streptocide consists of 4 stages:
1. Acylation
acetanilide
2. Sulphochloration
HN
O
O
C
C
CH3
HN
+ HOSO2Cl
CH3
+ H 2O
SO2Cl
p-chlorsulfonilacetanilide
3. Amidation
O
O
C
C
HN
HN
CH3
+
CH3
+ HCl
NH3
SO2NH2
SO2Cl
p-sulfamoilacetanilide
4. Hydrolysis
O
C
HN
CH3
NH2
+ CH3COOH
+ H2O
SO2NH2
SO2NH2
streptocide
Streptocide has amphoteric properties:
NH2
NH2
HCl
NаOH
+
SO2NH Nа
+
NH3
Cl
SO2NH2
SO2NH2
22.Sulphanylamidic preparations
Sulfanilamide is a molecule containing the sulfonamide functional
group attached to an aniline. Sulfanilamide is a sulfonamide antibiotic.
The sulfonamides are synthetic bacteriostatic antibiotics with a wide
spectrum against most gram-positive and many gram-negative
organisms. However, many strains of an individual species may be
resistant. Sulfonamides inhibit multiplication of bacteria by acting as
competitive inhibitors of p-aminobenzoic acid in the folic acid
metabolism cycle. Bacterial sensitivity is the same for the various
sulfonamides, and resistance to one sulfonamide indicates resistance
to all. Most sulfonamides are readily absorbed orally. However,
parenteral administration is difficult, since the soluble sulfonamide
salts are highly alkaline and irritating to the tissues. The sulfonamides
are widely distributed throughout all tissues. High levels are achieved
in pleural, peritoneal, synovial, and ocular fluids. Although these
drugs are no longer used to treat meningitis, CSF levels are high in
meningeal infections. Their antibacterial action is inhibited by pus.
Mechanism of action: Sulfanilamide is a competitive inhibitor of
bacterial para-aminobenzoic acid (PABA), a substrate of the enzyme
dihydropteroate synthetase. The inhibited reaction is necessary in
these organisms for the synthesis of folic acid. Indication: For the
treatment of vulvovaginitis caused by Candida albicans
Sulphanylamidic preparations. All sulphanylamidic
medicines contain the next fragment:
O
O
O2S
N
H
NH2
NH2
NH2
O2S
C
CH3
Albucyde
Альбуцил,
сульфацил
(sulphacyl)
N
H
NH2
O
N
O2S
C
NH2
Urosulphane
Уросульфан
N
H
S
Норсульфазол
Norsulphazol
O2S
N
H
C
N
H
C 4H9
Bucarbane
Букарбан
Albucyde (sulphacyl) – is an antibacterial mean, is a part of
eye-drops.
Urosulphane – is an antibacterial mean by infection of urinal
canals.
Norsulphazol – is used by pneumonia, meningitis,
staphylococcal and streptococcal sepsis, infectious diseases.
Bucarbane – is a hypoglycemic mean.
23. Medicinal preparations (derivates of p-aminobenzoic
acid (pABA).
NH2
NH2
COOH
COOC 2H5
Анестезин
Anaesthesine
COO-CH2-CH2-N(C 2H5)2 . HCl
N
H
H3C
CH3
Прокаїн (новокаїн) гідрохлорид
кислота
procaine (novocaine) hydrochloride Мефенамінова
mefenaminic
acid
Anaesthesine – is used as an 5-10% ointment or powder by
wounds, urticaria or skin diseases which are characterized by
itching.
Procaine (novocaine) hydrochloride – is a local
anaesthetic.
Mefenaminic acid – is an anaesthetic substance,
antiinflamed and antipyretic mean, is used by parodontosis.
4-Aminobenzoic acid (also known as paraaminobenzoic acid or PABA) is an organic
compound with the molecular formula C7H7NO2.
PABA is a white crystalline substance that is only
slightly soluble in water. It consists of a benzene
ring substituted with an amino group and a
carboxyl group. PABA is an essential nutrient for
some bacteria and is sometimes called Vitamin Bx.
In humans, PABA is normally made by E. coli in
the colon and therefore PABA from food is not
normally essential to human health. PABA is
therefore not officially classified as a vitamin. PABA
is an intermediate in bacterial synthesis of folate.
Although humans lack the ability to synthesize
folate from PABA, that is also normally done by E.
coli. PABA is sometimes marketed as an essential
nutrient for use whenever normal PABA synthesis
by intestinal bacteria is insufficient.
Medical use of 4-Aminobenzoic acid (also
known as para-aminobenzoic acid or PABA)
The potassium salt is used as a drug against
fibrotic skin disorders, such as Peyronie's
disease, under the trade name Potaba. PABA is
also occasionally used in pill form by sufferers of
Irritable bowel syndrome to treat its associated
gastrointestinal symptoms, and in nutritional
epidemiological studies to assess the
completeness of 24-hour urine collection for the
determination of urinary sodium, potassium, or
nitrogen levels.
24. Diazocompounds
Diazocompounds are organic compounds that contain NNgroup which is connected with hydrocarbon radical and
radical of mineral acid. The general formula of
diazocompounds is:
RN2X, where
R – is a hydrocarbon radical
X – is a radical of mineral acid (Cl−, Br−, NO3−, SO4H−,
OH−, CN−, SO3H−, SH−.
There are aliphatic and aromatic diazocompounds. But
aromatic diazocompounds are more important for
production of dyes and medicines, in pharmaceutical
analysis.
The general formula of aromatic diazocompounds is
ArN2X, where
Ar – is an aromatic radical
X – is a radical of mineral acid (Cl−, Br−, NO3−, SO4H−,
OH−, CN−, SO3H−, SH−.
In acid medium aromatic diazocompounds have ionic
structure and they are called salts of diazonium (Ar–
N+≡NX−). In neutral medium aromatic diazocompounds
have covalent structure (Ar–N=N–X). In alkaline medium
aromatic
diazocompounds are diazotates.
кисле середовище
середовище
+
+
NаOH
+ Аr - N N OH
+
Аr - N NаOH
N Cl
Аr - N N
N N Cl
acid
medium середовище
нейтральне
нейтральне середовище
Аr - N = N - OH
NаOH
Аr - N = арилдіазогідроксид
N - OH
арилдіазогідроксид
OH
лужнеmedium
середовище
neutral
лужне середовище
NаOH
+
Аr - N = N - O Nа
+
Аr - N арилдіазотат
= N - O Nанатрію
арилдіазотат натрію
alkaline medium
The systematic (IUPAC) name of aromatic
diazocompounds is obtained by adding the suffix “-diazo”or “-dizonium-” (in the case of salts of diazonium). For
example:
С6H5 - N = N - OH
С
H5 - N = N - OH
6
бензолдіазогідроксид
benzenediazohydroxide
бензолдіазогідроксид
Cl
N = N - CN
4-хлорбензолдіазоціанід
Cl
N = N - CN
4-chlorobenzenedizocyanide
4-хлорбензолдіазоціанід
++
С6H5 - N = N - O Nа
С6бензолдіазотат
H5 - N = N - Oнатрію
Nа
sodium
benzenediazotate
бензолдіазотат
натрію
+
H3C
N
+
N Cl
4-метилбензолдіазоній хлорид
H3C
N
N Cl
4-methylbenzenediazonium
chloride
4-метилбензолдіазоній
хлорид
Physical properties salts of diazonium
Salts of diazonium are colorless crystalline substance,
easily soluble in water. They are unstable on heating and
mechanical actions of explosion.That why decomposed in
reactions usually use them freshly prepared aqueous
solutions
25. The methods of extraction of aromatic diazocompounds
1.
Reaction of diazotation
NH 2
+
R
2.
N N Cl
+
NаNO2, HCl excess
R
NаCl + H2O
Reaction of aromatic amines with
alkylnitrites
+
C6H5 - NH2 + C2H5 -O-N=O + HCl
С6H5 - N
NCl
+ C2H5OH + H2O
Reaction mechanism of diazotation :
H
HO - N=O + H
+
+
N = O + H2O
H-O-N=O
+
H
+
C6H5 - NH2 + N=O
..
+
C6H5 - N - N=O
-H
+

C6H5 - N - N=O
H
H

+
С6H5 - N = N - OH
benzendiazohydroxide
С6H5 - N N Cl
+ H2O
26. Chemical properties of aromatic
diazocompounds
I. Reaction with extraction of N2
C6H5SO2Cl + N2
SO2, CuCl, t
CuBr, t
C6H5Br + N2 + KCl
+KBr
C6H5Cl + N2
CuCl, t
+
С6H5 - N
NCl
KCN, CuCN, t
C6H5CN + N2 + KCl
CH2=CH -X + MeАn
C6H5 -CH2 - CH - X
Аn
II. Reaction without extraction of N2 :
a) Formation of diazoderivatives
C6H5–N≡N–Cl + 2NaOH → C6H5–N=N–ONa + NaCl + H2O
C6H5–N≡N–Cl + CH3–NH2 → C6H5–N=N–NH–CH3 + HCl
C6H5–N≡N–Cl + NaCN → C6H5–N=N–CN + NaCl
b) Reduction (catalysts are SnCl2 and HCl)
[H]
C6H5–N≡N–Cl + 2SnCl2 + 4HCl → C6H5–NH–
NH2∙HCl + 2SnCl4
c) Reaction of azojoining
Cl
N
N
NH2
H+
+
N
N
NH2 + HCl
4- aminoazobenzene
III. Reactions of substitution
C6H5–N≡N–Cl + HOH → C6H5OH + N2 + HCl
C6H5–N≡N–Cl + KI → C6H5I + N2 + KCl
C6H5–N≡N–Cl + H3PO2 + HOH → C6H6 + N2 + HCl
+ H3PO3
27.Azocompounds
Azocompounds are organic compounds that contain -N=N-group which
is connected with 2 hydrocarbon radicals.
There are aliphatic and aromatic azocompounds.
3/
HO
2/
1/
4/
1
N=N
2
8
3
4
N=N
1
2
OH
7
NH2
4-amino-2-hydroxiazobenzene
3
6
5
4
benzene-2-hydroxiazonaphtalene
Physical properties of azocompounds
Azocompounds are crystalline substances, colored in
yellow, orange, red, blue and other colors. This feature
allows you to use many of them as a means of
chemotherapeutic means
28.The methods of extraction of aromatic azocompounds.
1. Formation of diazoderivatives
C6H5–N≡N–Cl + 2NaOH → C6H5–N=N–ONa + NaCl + H2O
C6H5–N≡N–Cl + CH3–NH2 → C6H5–N=N–NH–CH3 + HCl
C6H5–N≡N–Cl + NaCN → C6H5–N=N–CN + NaCl
2. Reduction nitroarenes in alkaline medium (reaction with
Zn + NaOH) .
[H]
C6H5–NO2 ↔
C6H5–N=N–C6H5
azobenzene
29. Chemical properties of aromatic
azocompounds:
Chemical properties are specified by group –N=N–:
1.Reaction with mineral acids:
C6H5–N=N–C6H5 + HCl ↔ C6H5–N+H=N–C6H5 + Cl¯
2. Oxidation (reaction with peroxiacids)
[O]
C6H5–N=N–C6H5 ↔ C6H5–N+O ¯ =N–C6H5
3.Reduction (reaction with Zn + NaOH)
[2H]
C6H5–N=N–C6H5 ↔ C6H5–NH–NH–C6H5
30. Physical bases of theory of colouration.
The theory of colouration studies the dependence
of colour of organic compounds on the structure of
molecules. The colour of any compound is
specified its ability to absorb electromagnetic
radiation. Color or colour (see spelling differences)
is the visual perceptual property corresponding in
humans to the categories called red, yellow, blue
and others. Color derives from the spectrum of
light (distribution of light energy versus
wavelength) interacting in the eye with the spectral
sensitivities of the light receptors. Color categories
and physical specifications of color are also
associated with objects, materials, light sources,
etc., based on their physical properties such as
light absorption, reflection, or emission spectra.
Structural fragments of molecule which cause
the certain colour are called chromophores.
The main chromophores are the next groups:
–N=N–
–NO2
–N=O
In the structure of molecule there are groups
which can amplify the colour of compound.
They are called auxochromes. They are the
next groups:
1)–OH
2) –NH2
3) –NHR
4) –NR2
5)–OR
6) –SH
The colors of the visible light spectrum
wavelength
interval
frequency
interval
red
~ 700–635 nm
~ 430–480 THz
orange
~ 635–590 nm
~ 480–510 THz
yellow
~ 590–560 nm
~ 510–540 THz
green
~ 560–490 nm
~ 540–610 THz
blue
~ 490–450 nm
~ 610–670 THz
violet
~ 450–400 nm
~ 670–750 THz
color
Color, wavelength, frequency and energy of light
Color
Infrared
λ/nm
ν/1014
Hz
νb/104
cm−1
E/eV
E/kJ
mol−1
>1000
<3.00
<1.00
<1.24
<120
Red
700
4.28
1.43
1.77
171
Orange
620
4.84
1.61
2.00
193
Yellow
580
5.17
1.72
2.14
206
Green
530
5.66
1.89
2.34
226
Blue
470
6.38
2.13
2.64
254
Violet
420
7.14
2.38
2.95
285
Near
ultraviolet
300
10.0
3.33
4.15
400
Far
ultraviolet
<200
>15.0
>5.00
>6.20
>598
In the 1969 study Basic Color Terms: Their
Universality and Evolution, Brent Berlin and Paul
Kay describe a pattern in naming "basic" colors
(like "red" but not "red-orange" or "dark red" or
"blood red", which are "shades" of red). All
languages that have two "basic" color names
distinguish dark/cool colors from bright/warm
colors. The next colors to be distinguished are
usually red and then yellow or green. All
languages with six "basic" colors include black,
white, red, green, blue and yellow. The pattern
holds up to a set of twelve: black, grey, white,
pink, red, orange, yellow, green, blue, purple,
brown, and azure (distinct from blue in Russian
and Italian but not English).
31.Azo dyes
Azo dyes are dyes with -N=N- azo structure as a
O
chromophore.
C
OH
CH3
N
N
N
CH3
methylred
CH3
SO3Na
N
N
N
CH3
methylorange
Methyl orange is a pH indicator frequently used in
titrations. It is often chosen to be used in titrations
because of its clear colour change. Because it changes
colour at the pH of a mid-strength acid, it is usually used
in titrations for acids. Unlike a universal indicator, methyl
orange does not have a full spectrum of colour change,
but has a sharper end point.
In a solution becoming less acidic, methyl orange
moves from red to orange and finally to yellow
with the reverse occurring for a solution
increasing in acidity. It should be noted that the
entire colour change occurs in acidic conditions.
In an acid it is reddish and in alkali it is yellow.
Methyl red, also called C.I. Acid Red 2, is an indicator
dye that turns red in acidic solutions. It is an azo-dye,
and is a dark red crystalline powder. Methyl red is a pH
indicator; it is red in pH under 4.4, yellow in pH over 6.2,
and orange in between, with a pKa of approximately 5.
Preparation of methyl red
As an azo dye, methyl red may be prepared by
diazotization of anthranilic acid, followed by reaction with
dimethylaniline:
Methyl yellow, or C.I. 11020, is a chemical
compound which may be used as a pH indicator.
In aqueous solution at low pH, methyl yellow
appears red. Between pH 2.9 and 4.0, methyl
yellow undergoes a transition, to become yellow
above pH 4.0. Additional indicators are listed in
the article on pH indicators. As "butter yellow" the
agent had been used as a food additive before its
toxicity was recognized.
Thank you for attention!