organic chemistry solomons fryhle

Organic chemistry I
Zdeněk Friedl
Chapter 1
Basic concepts
Solomons & Fryhle: Organic
Chemistry 8th Ed., Wiley 2004
Basic concepts
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subject of organic chemistry
atomic and molecular orbitals, LCAO method
bond length, bond angle
bond-dissociation energy, bond energy
electronegativity, polarity of bonds
dipole moment
electronic effects, inductive (I) and mesomeric (M) effect
steric effect
2
The subject of organic chemistry
3
sp3
hybridization of atomic orbitals
4
Formation of methane
from sp3 hybridized C atom and four H atoms
5
Formation of ethane
from two sp3 hybridized C atoms and six H atoms
6
sp2
hybridization of atomic orbitals
7
The σ-skeleton and π-bond in ethene molecule
8
sp
hybridization of atomic orbitals
9
The structure of ethyne
10
The structure of benzene
11
Structural formulas of benzene
12
The delocalization energy
Compound
Heat of
hydrogenation
1,3-pentadiene
1,4-pentadiene
cyklopentadiene
benzene
furan
Delocalization
energy
calc.
exptl.
(kJ mol-1)
242.9
254.6
225.1
358.2
225.1
226.6
254.6
213.5
208.5
153.2
16.0
0
12.0
149.7
71.9
13
Formation of
σ C-C
and
π C=C
bond
14
Formation of
σ C-O
and
π C=O
bond
15
The bond length
16
Bond lengths and bond angles of
C-C bonds
17
The homolytic bond dissociation
18
Homolytic bond dissociation energies
19
Bond energies
kJ mol-1
C – H 413
N – H 391
O – H 463
C – C 346
C = C 610
C ≡ C 837
C–F
C – Cl
C – Br
C–I
C – N 309
C = N 615
C ≡ N 887
444
339
284
213
C – O 357
C = O 737
20
The electronegativity of selected atoms
21
The electron density map for
H-X
molecule
22
The dipole moment
µ
=
(charge)
q x (distance) d
[D] Debye
10-30 [C m] = 0.3 D
esu
SI
23
Physical properties of some cis-trans isomers
24
Attractive electric forces
25
Attractive forces in simple covalent compounds
26
Hydrogen bonds
(dipole-dipole attractions)
27
The separation of principles and effects
28
Electronic effects
( inductive
I / mesomeric M )
29
Steric effect at o-substituted benzaldehydes
H
O
H
CH3
CH3
C CH3
CH3
30