, Exam / review
Chapter 14 conjugated compounds : and UV spectroscopy
Conjugated compounds
↳ compounds with
alternating double and single bonds
↳
They by using base induced elimination of
are made HX from an Allylichalide
↳ The middle
single bond in a conjugated diene is shorter
HA Br
NBs KockHala
than a non conjugated one ↑
due to orbital hybridizati 4 HOC((Hzbe
Cyclohexene S-Bremocyclohexene 1,
3-Cyclohexadiene (76 %)
·
substituted alkenes are more Produce less heat
stable and
So they release heat when added to water
one diff btwn cony dienes and alkenes
.
is electrophilic addition rxns
1,2 & 1
,
4 addition
Sometimes conj. dienes can get 2 products and ,
one will have the alkene on the central
Carbon 1 2 1, 4
,
HBr
Nisr
-
x +
1 ,
3-butadiene It i
1 ,
2
1 4
Br 2
,
- -Br
20 %
Br
t
B Bo
d Inajor Minor
12
129134
#
2
1 ,
"
+
it [a
c Kinetic
T
therm
namic
1, 2 1 4
Kinetic and themodynamic control
,
Kinetic control : The Product of an irreversible ran. depends on reletve ratos not stability
↳ Low Product with lower Ea will form greater amounts
temp ; Irreversible .
in
thermodyname control : Product is reversable depends on Stability ,
not relative rates
↳ high temp ; reversable
.
when we have an Irreversbe lower tempran ,
product will depend relate rates . If we have a
higher temp reversable rxy , major product will depend on stability
Diels-alder cycloaddition reaction
↳ cons-dienes
undergo an addition run with alkenes to make subst Cyclohexone products·
, dienophile
diene O
diels-alder rxn =
DAR
.
5 y or #
S
↳3 butadene 3-butene-2-ove 3- Cy clohexany
methyl ketone
↳
This process is called the diels- alder cycloaddition reaction
not polar or radical
dienophile : alkene Part of DAR
(dieve cover)
*
DAR can
happen quicker when the dienophile has an EW Substituent Group Stereospecific : a single
Product Stereoisomer is formed . e
ex
alkynes can
i
·
also act as dienophiles .
can as product , trans Product
b UV Spec
Predict the following diels -
alder rxn endo (Syn) .
-1 P electrons can be shifted
by Ultraviolet light
>
-
-
Y
When "white
- light strikes
-
a cony
Molecule
. The wavelength needed for
exitation is Absorbed
The dienophile
·
has to have an ewo and can sometimes have a triple bond
Stereochemistry of dienophile Maintained during the reaction
·
the is
The Diene
·
has to have (is-like") Conformation to do DAR .
to create
Some can rotate a S-cis Conformation
rigid ones can't
·
.
·
diens are very reactive and have an s-as geometry
Diene Polymers
·
like simple alkenes , con) · diones can polymerized
-
because double bonds remain in the Polymer as-trans isomerism is possible -
Polymerizati Can be initiated by radical add
-
or
Polymereati addition
-
Occurs via 1 4
,
HOMO highest electron filled orbital
!
:
Lumo : Lowest electron Poor orbital
Y2-Ys is hom
N4-Ns is Lumo
, 15 Benzene and aromaticity
Chapter
:
CHs
#
naming
Exis
aromatic compounds :
-
a lot of aromatic compounds have nonsystemic names
O-zylene
-more substituted benzenes are named the same way as other hydrocarbons ,
with benzene as the parent
tolvene Phenal anilive benzaldehyde
name
Exc KJXN
, G
alkyl Subst benzenes are named 2 ways :
alkyl-substituted Pheny
. in
If the alkyl substituent has 6
·
or less carbons its named as an
If the
alky) substituent has than 6 carbons Its named phenyl-substituted alkone
·
more , as a .
The Cotto CHy group denzyl group and the
Cals-group phenyl group
·
is a is a
disubstituted benzenes
↳ named
by the Ortho (0) meta (m) ,
and Para(p) system
,
O-dichlorobenzene
or tho met a Para P
-C3 #i
I . &
I Eis Br
**
Bir
M-Bromofoliere p-chloroBromobenzene
benzene with more than 2 substituents are named by numbering the position of each substituent
↳
Name like any other
namey
of benzene
Stability
addition products
benzene reacts Slowly with Bra give substitution
to not
-
,
↳ all
C-c bonds at benzene have the same length
-
benzene is Planar with all bond angles at 1200
&doe
& double bonds
-All carbons are sp2 hybridized and identical 4 it electrons
1 I antaromatic
aromatic
aromaticity aromaticity
huckel
The 4n +2 rule Cyclic Conjugated follows huckels rule
·
Planar ,
-
, ,
-
for to be arematic , i has to fulfill hickes rule
a
compound
hickes rule : a compound is only crematic If I has a plather , Monocycli system of Conjugati with a total of 4nt2
electrons
-
Molecules with (4 ,
8 , 12 ...
) are anticromatic
ex .
Cyclobutadiene (n 4) is =
anti
benzene (n c) aromatic =
Aromatic lons
·
any cyclic cony. Molecule with An + 2 electrons can be aromatic even ifIts an on
,
Chapter 14 conjugated compounds : and UV spectroscopy
Conjugated compounds
↳ compounds with
alternating double and single bonds
↳
They by using base induced elimination of
are made HX from an Allylichalide
↳ The middle
single bond in a conjugated diene is shorter
HA Br
NBs KockHala
than a non conjugated one ↑
due to orbital hybridizati 4 HOC((Hzbe
Cyclohexene S-Bremocyclohexene 1,
3-Cyclohexadiene (76 %)
·
substituted alkenes are more Produce less heat
stable and
So they release heat when added to water
one diff btwn cony dienes and alkenes
.
is electrophilic addition rxns
1,2 & 1
,
4 addition
Sometimes conj. dienes can get 2 products and ,
one will have the alkene on the central
Carbon 1 2 1, 4
,
HBr
Nisr
-
x +
1 ,
3-butadiene It i
1 ,
2
1 4
Br 2
,
- -Br
20 %
Br
t
B Bo
d Inajor Minor
12
129134
#
2
1 ,
"
+
it [a
c Kinetic
T
therm
namic
1, 2 1 4
Kinetic and themodynamic control
,
Kinetic control : The Product of an irreversible ran. depends on reletve ratos not stability
↳ Low Product with lower Ea will form greater amounts
temp ; Irreversible .
in
thermodyname control : Product is reversable depends on Stability ,
not relative rates
↳ high temp ; reversable
.
when we have an Irreversbe lower tempran ,
product will depend relate rates . If we have a
higher temp reversable rxy , major product will depend on stability
Diels-alder cycloaddition reaction
↳ cons-dienes
undergo an addition run with alkenes to make subst Cyclohexone products·
, dienophile
diene O
diels-alder rxn =
DAR
.
5 y or #
S
↳3 butadene 3-butene-2-ove 3- Cy clohexany
methyl ketone
↳
This process is called the diels- alder cycloaddition reaction
not polar or radical
dienophile : alkene Part of DAR
(dieve cover)
*
DAR can
happen quicker when the dienophile has an EW Substituent Group Stereospecific : a single
Product Stereoisomer is formed . e
ex
alkynes can
i
·
also act as dienophiles .
can as product , trans Product
b UV Spec
Predict the following diels -
alder rxn endo (Syn) .
-1 P electrons can be shifted
by Ultraviolet light
>
-
-
Y
When "white
- light strikes
-
a cony
Molecule
. The wavelength needed for
exitation is Absorbed
The dienophile
·
has to have an ewo and can sometimes have a triple bond
Stereochemistry of dienophile Maintained during the reaction
·
the is
The Diene
·
has to have (is-like") Conformation to do DAR .
to create
Some can rotate a S-cis Conformation
rigid ones can't
·
.
·
diens are very reactive and have an s-as geometry
Diene Polymers
·
like simple alkenes , con) · diones can polymerized
-
because double bonds remain in the Polymer as-trans isomerism is possible -
Polymerizati Can be initiated by radical add
-
or
Polymereati addition
-
Occurs via 1 4
,
HOMO highest electron filled orbital
!
:
Lumo : Lowest electron Poor orbital
Y2-Ys is hom
N4-Ns is Lumo
, 15 Benzene and aromaticity
Chapter
:
CHs
#
naming
Exis
aromatic compounds :
-
a lot of aromatic compounds have nonsystemic names
O-zylene
-more substituted benzenes are named the same way as other hydrocarbons ,
with benzene as the parent
tolvene Phenal anilive benzaldehyde
name
Exc KJXN
, G
alkyl Subst benzenes are named 2 ways :
alkyl-substituted Pheny
. in
If the alkyl substituent has 6
·
or less carbons its named as an
If the
alky) substituent has than 6 carbons Its named phenyl-substituted alkone
·
more , as a .
The Cotto CHy group denzyl group and the
Cals-group phenyl group
·
is a is a
disubstituted benzenes
↳ named
by the Ortho (0) meta (m) ,
and Para(p) system
,
O-dichlorobenzene
or tho met a Para P
-C3 #i
I . &
I Eis Br
**
Bir
M-Bromofoliere p-chloroBromobenzene
benzene with more than 2 substituents are named by numbering the position of each substituent
↳
Name like any other
namey
of benzene
Stability
addition products
benzene reacts Slowly with Bra give substitution
to not
-
,
↳ all
C-c bonds at benzene have the same length
-
benzene is Planar with all bond angles at 1200
&doe
& double bonds
-All carbons are sp2 hybridized and identical 4 it electrons
1 I antaromatic
aromatic
aromaticity aromaticity
huckel
The 4n +2 rule Cyclic Conjugated follows huckels rule
·
Planar ,
-
, ,
-
for to be arematic , i has to fulfill hickes rule
a
compound
hickes rule : a compound is only crematic If I has a plather , Monocycli system of Conjugati with a total of 4nt2
electrons
-
Molecules with (4 ,
8 , 12 ...
) are anticromatic
ex .
Cyclobutadiene (n 4) is =
anti
benzene (n c) aromatic =
Aromatic lons
·
any cyclic cony. Molecule with An + 2 electrons can be aromatic even ifIts an on
,
