Summary Organic and Biosynthesis - Organic chemistry part (WBFA008-05)

Organic & Biosyntnesis

, Lecture 1 Lecture 2
Chapter 1 Chapter 8 ( Hs -

µH
Îî
>
Non paar covalent bond =
Atoms are the same or have
>
Loca / ized electro ns =

belang to single atom 01 are shared by two locatie e
electron

'
Delocalized electro ns shared by 3 atoms partia / double bonds
negativ ities
=
similar electro or more →



↳ resonance
→
H -
H F- F C- ( C -
H

>
[
'

hybrid has partial bonds &
•

'
Polar Atoms have different electro nega
→
charges
covalent bond = -



resonance resonance
tivity ' Ontributor contributie •

de / ocalized electro ns result from the P Orbital Of One



atom
overlapping the porbitals of twoadjacent Atoms
> resonance
Atomic Orbital =
region of Space arouna the nucleus wnere maria




an electron is mostapt to be found ' '
( complete octet )
4 z
Drawing resonance :
electro ns cannot moue to an sp Carbon




¥1
•
P Orbitals 3 Zpx / 2 / zpz
→ :
Py •


double
× double single bond → al / atoms have empty p Orbit als
-




/
-




↳ if 2 Overlap → 1T bond ↳
zpx Orbital

}
Stability
•

Sp Orbital due to nybridization
}
1 SP
109.5° ga Separate d charges
°
>
( ,
incomplete octet ,
or a positive charge on an electro negati
j
_
• 0 bond
,☐
g. g-




g⑦
atom ( or vice versa ) makes a compound ¥ stable

°

The stable resonance Contributions the the delocalization En
• ?
Orbital double bond
moore ,
greater
Sp :




> 0 bond
b Sp
'
-
s / Sp
'
overlap
0④0 \
④
↳
contributies more to hybrid

ÈÏÏ }
1T bond °
' ( diene
„ 6.60 onjugateddiene more stable than isolated
> 1
,


④ (Hz (H CH = (H CH 3 (Hz CH ( H2 CH CHZ
= - - = -
- =


•


Sp Orbital :
trippte bond / (0 S ?
b Sp Why
-


0 b Sp sp -




CIC overlap
- -
overlap
>
IS >
electron de/ ocalization ( resonance )
180°
>
hybridization of Orbit als


Chapter
°

5 relative Stability of carbocations :




Ëf
lea


ÉRR Én
" °"
stable ÈHZ = (Hr = CHÉHZ =
R , r -
> R -
> H -
> ( H2 = ÉH S
positive charge
-


>
Electropnile Parti at positive Or an
charge
=
,
, .
benul " "
4 '
metny ,
vinyl
cation cation tertiary Secondary primary
carbokation cation cation
carbokation carbokation

incomplete octet
↳
Substituten of -
R makes more stable
>
nucleophile Negative charge Lone pair it
=
,
or a bond °
Delocalized electro ns pka acid → release of proton like
towers →
Stronger more

↳ electron s to share

'
arrows from nucleophile → electro phik →
important




>
reaction coorainate diagram shows energy Changes



-]Ë
9 Íation
-




DÉ Electronic Effects
Es
'
A- - - -
Ter-94 lrineti
"
kinetic Stability :




[
0

Ë
'




free °
+
Electron donation
•
( enermoaynam.is )
o energy B ↳
stable
destabilizes the base → decreases acidity 2

genant Large -1 Slow
=
-
- -
'




± :
Electron withdraw at stabilis.es →
aciaity
°
the base increases z


thermodynamicaability : DÓ
reaction progress Inductie electron
°
withdraw at withdrawat of electrons bond
through 0
=



↳ is stable
Negative product
=

>
substituent to ( ÙHS)
benzene
ring moreel
ectronegatiue than
hydrogen
> transition state (t ) → partieel bonds +
charges °
Electron (
donationbyhyperconjugation-donatingelectrons.to a p Orbital

highest energy DÉ
>
rate limiting step Slowestkinetics
= =
°
Electron donati on by resonance =
substituent with lone pair on atom at


Ched to benzene
ring → Ione pair can be delocalized into ring ( NH2.OH.C

Chapter 6 '
also withdraw electro ns inductiveiy ( more electro
negatie )
> Substitute ons
'

( R) stabilize compound
°
Electron withdraw at substituent to ring aoublyltriplybon
-




a resonance is
by
=



R "

R -




CÉR Moore stable than R -
[
É H
to amore electro
negative atom → electrons from ring onto substituent (( = 0


withdraw electro ns inductiveiy ( more
negatie )
> also electro




ijijijij