This document discusses the structures, properties, and reactions of various classes of hydrocarbons including alkanes, cycloalkanes, alkenes, alkadienes, and alkynes. It provides details on hydrocarbon nomenclature, isomerism, structural features, methods of preparation in the laboratory, and characteristic chemical reactions such as halogenation, nitration, oxidation, cracking, and isomerization. Cycloalkanes exhibit different types of isomerism compared to acyclic alkanes including ring size, positional, and enantiomeric isomerism. Cyclopropane has a unique planar structure compared to other cycloalkanes.
2. Reactivity of saturated hydrocarbons
(alkanes, cycloalkanes). Reactivity of
unsaturated hydrocarbons (alkenes,
alkadienes, alkynes)
3. Hydrocarbons: aliphatic and alicyclic
Class name
hydrocarbon
General
formula
Type of
hybridization
carbon atom
Basic
type of reaction
Features
structures,
endings in the
name
Akanes
Alkenes
Alkadienes
Alkynes
Cecloalkanes СnН2n
СnН2n-2
СnН2n-2
СnН2n
СnН2n+2
sp3, tetrahedron,
109028/
sp2, planar,
1200
sp2, planar,
1200
sp, linear,
1800
sp3, tetrahedron,
109028/
Everyone
(С-С)
- ane
1 С=С, 1,
all others ;
- ene
2 С=С, 2,
all others ;
- diene
1 СС, 2,
all others ;
- yne
Atoms S
closed in a cycle,
Cyclo- -ane
SR; cracking
isomerization,
oxidation
AE;
polymerization,
oxidation
1,2- та 1,4 AE;
polymerization,
oxidation
AE;
polymerization,
CH-acid properties.
oxidation
SR;
addition,
oxidation
7. HC C CH
CH3
CH3
3-methylbutyn-1
C C
CH2
1-phenyl propene (methyl phenyl acetylene)
C C
H HC C CH2
Ethynyl- Propargyl-
Hydrocarbons: nomenclature and isomerism
8. Structural isomerism
С5Н12
H3C CH2 CH2 CH2 CH3
H3C CH CH2 CH3
CH3
H3C C CH3
CH3
CH3
pentane
boil. point = 36.2С
2-methylbutane
boil. point = 28С
2,2-dimethylpropane
boil. point = 9.5С
Hydrocarbons: nomenclature and isomerism
10. Spatial isomerism
C C
H3C CH3
H H
C C
H3C
CH3
H
H
cis-butene-2
boil. point =4С
trans-butene-2
boil. point =1С
11. C C
O2N Cl
H
H
C C
O2N H
Cl
H
cis-1-chloro-2-nitroethene trans-1-chloro-2-nitroethene
C C
O2N Cl
CH3
Br
C C
O2N CH3
Cl
Br
(E)-1-bromo-2-chloro-1-nitropropene
(Z)-1-bromo-2-chloro-1-nitropropene
12. HC C CH
CH3
CH3 HC C CH2CH2CH3
H3C C C CH2CH3
3-methylbutyn-1 pentyn-1
pentyn-2
Structural isomerism
16. Alkane preparation methods
Laboratory :
1. Alkaline melting (Dumas synthesis)
RCOONa + NaOH R–H + Na2CO3
For example, to obtain butane, you need to take:
СН3-СН2-СН2-СН2-СООNa + NaOH
СН3-СН2-СН2-СН2–H + Na2CO3
2. Hydrolysis of organomagnesium compounds :
R-Mg-Hal + HOH → R–H + Mg(OH)Hal
For example, to obtain butane, you need to take :
СН3-СН2-СН2-СН2-Mg-Hal + HOH →
СН3-СН2-СН2-СН2–H + Mg(OH)Hal
2
)
(OH
Ca
2
)
(OH
Ca
сплавлення
Alkanes are called aliphatic hydrocarbons, in the molecules of which
the carbon atoms are linked by simple covalent σ bonds.
alloying
17. 4. Kolbe reaction (electrolysis)
RCOONa RCOO– + Na+
RCOO– – 1е R + СО2
R + R R – R
For example, to obtain hexane, you need to take:
СН3-СН2-СН2-COONa СН3-СН2-СН2-COO– + Na+
СН3- СН2-СН2-COO– – 1е СН3-СН2-СН2
+ СО2
СН3- СН2-СН2
+ СН3-СН2-СН2
СН3-СН2-СН2–СН2-
СН2-СН3
Alkane preparation methods
18. 3. The Wurtz reaction:
R–Hal + 2Na + Hal–R 2NaHal + R–R
Mechanism:
R–Hal + 2Na R–Na + NaHal
RNa + Hal–R NaHal + R–R
For example, to obtain hexane, you need to take:
СН3-СН2-СН2–Сl + 2Na + Сl–СН2-СН2-СН3 2NaСl
+ СН3-СН2-СН2–СН2-СН2-СН3
Alkanes preparation methods
19. 5. Hydrogenation of alkenes and alkynes:
СН3–С≡С–СН3 + Н2 СН3–СН=СН–СН3 + Н2
СН3–СН2–СН2–СН3
6. Alkane cracking – production of alkenes and
alkanes:
C20H42 C10H20 + C10H22
7. Production of methane:
Al4C3 + 12HCl 4AlCl3 + 3CH4
Pt
Ni
t
Alkanes preparation methods
22. Alkanes. Chemical properties
Halogenation (Reaction Mechanism)
1. Halogenation begins only under the action of the initiator
of radical reactions (UV light, radical reagents, heating).
2. The reactivity of halogens decreases in the series:
F2 > Cl2 > Br2 > I2
3. Halogenation under the influence of fluorine and chlorine
can get out of control and become explosive.
23. 4. The reactivity of Hydrogen at the tertiary Carbon atom is
higher than at the secondary, and the secondary is higher
than at the primary.
CH3 C
CH3
CH3
CH3 CH CH3 CH3CH2 CH3
> > >
376 kJ/mol 390 kJ/mol 415 kJ/mol
Alkanes. Chemical properties
Halogenation (Reaction Mechanism)
28. Oxidation
Strong oxidizers (KMnO4, K2Cr2O7 etc.)
R CH2 CH2 R
[O]
катализатор
R CH2OH
R C
O
H
R COOH
CH3CH2CH2CH3
O2, t
kat
2CH3COOH + H2O
Alkanes. Chemical properties
catalyst
catalyst
29. Cl
CH3
1
2
3
4
5
1-Метил-2-хлоро-
циклопентан
CH2 CH3
1
2
3
4
5
6
3-Етилциклогексен
A large group of cycloalkanes consists of bicyclic compounds
with disconnected rings, with directly connected single C–C or
double C=C bonds, spirane, bridging.
Циклопропан
CH2
H2C CH2
або
CH2 CH2
CH2 CH2
або
Циклобутан
Classification
Циклоалкани
Cyclopropane Cyclobutane
3-ethylcyclohexane
1-chloro-2-
methylcyclopentane
1
2
or or
30. Structural isomerism depends on the size of the
cycle, the nature of the element, their relative
location and is divided into the following types:
1. Ring Size Isomerism
2. Isomerism of the position of the substituent
3. Isomerism of side chains
4. Isomerism by the number of carbon atoms in lateral
substituents
Cl
H
H
Cl
H
H
Cl
H
H
H
Cl
H
цис-1,2-Дихлороцикло-
пропан (Z-ізомер)
транс-1,2-Дихлороцикло-
пропан (Z-ізомер)
1 1
2 2
3 3
cis-1,2-
dichlorocyclopropane
(Z-isomer)
trans-1,2-
dichlorocyclopropane
(Z-isomer)
31. Enantiomerism of alicyclic compounds occurs in the presence of
a chiral carbon atom and the absence of symmetry elements,
primarily the plane of symmetry. Thus, cyclopropane with two
substituents in the trans-1,2-position or with two different ones
both in the trans-1,2-position and in the cis-1,2-position exists in
the form of enantiomers :
Cl
H
H
H
Cl
H
H
Cl
H
Cl
H
H
H
C
H3
H
H
Cl
H
H
Cl
H
H
CH3
H
транс-1,2-Дихлороцикло-
пропан (Z-ізомер)
цис-1-Метил-2-хлоро-
циклопропан
Енантіомери (не
суміщаються при
накладанні)
Енантіомери (не
суміщаються при
накладанні)
Д
з
е
р
к
а
л
о
Д
з
е
р
к
а
л
о
CH3
H
H
C
H3
H
CH3
CH3
H
CH3
H
H
CH3
CH3
H
H
C
H3
Enantiomers (do not
mix when
superimposed)
trans-1,2-
dichlorocyclopropane
(Z-isomer)
Enantiomers (do not
mix when
superimposed)
cis-1,2-
dichlorocyclopropane
(Z-isomer)
m
i
r
r
o
r
m
i
r
r
o
r
32. Unlike all other cycloalkanes, cyclopropane has a planar carbon
skeleton. In cyclopropane, there is significant angular stress: the angles
of 60° between the straight lines connecting the nuclei of carbon atoms
are very different from the tetrahedral ones, in addition, the Н–С–Н
angles are 118°, which is close to the tetrahedral state of the carbon
atom. In order to remove the angular tension, the hybridized orbitals
actually overlap not along a straight line, but somewhat with a deviation
from it. As a result, C–C bonds are bent, they are called “banana” bonds
or π-bonds :
1040 600
220
C
H2
CH2
C
H
H
0,154 нм
116,40
1180
33. C
H3 CH2 CH3
+ H2
800
Pt, Ni
C
H3 CH2 CH2 CH3
+ H2
2000
C
H3 CH2 CH2 CH2 CH3
+ H2
3000
3000
Pt
CH2
CH2
CH2
X X
+ X2 (äå Õ - Br, I)
t
Chemical properties of cycloalkanes:
addition reactions
Where X – Br, Cl, I
34. CH3 CH2 CH2 Br
+ HBr
CH3 CH2 CH2 CH2 I
+ HI
OH
C
O
(CH2)4
HOOC COOH
[O] O2
-H2O
2O2
Циклогексан Циклогексанол Циклогексанон Адипінова кислота
Chemical properties: addition reactions
Chemical properties: oxidation reactions
Cyclohexane Cyclohexanol Cyclohexanone Adipic acid
