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HYDROLYSIS REACTIONS
HYDROLYSIS REACTIONS
O
CR O R
O
CR O
+
OH
_
+
R O H
O
CR O R
O
CR OH
+
+
R O H
H
2
O
H
2
SO
4
Hydrolysis of Esters
Hydrolysis of Esters
Basic Solution
Acidic Solution
excess
heat
heat
Hydrolysis requires strong acid or base and heating under re#ux.
… It’s not easy !
Na
+
Na
+
:
_
:
O
CR O R'
H O
:
:
O
CR O R'
OH
_
:
slow
:
:
O
CR O R'
OH
_
:
:
:
O
CR O R'
O
H
_
:
:
:
O
CR O R'
OH
_
:
:
:
O
CR
OH
:
O R'
:
+
R C O
O
:
_
O R'H
+
_
Hydrolysis of an Ester in Base
Hydrolysis of an Ester in Base
proton
transfers
H-OH
HO
-
NaOH
:
O
CR O R'
H
H O H
:
O
CR O R'
OH
H
H
slow
O
CR O R'
OH H
H
O
CR O R'
O
H
H
H
O
CR O R'
O H
H
H
:
+
:
O
CR O R'
O H
H
H
:
+
:
O
CR
OH
H
:
O R'
H
:
+
+
+
:
:
:
+
+
+
:
O
CR O H
Hydrolysis of an Ester in Acid
Hydrolysis of an Ester in Acid
proton
transfers
H
3
O
+
+ H
3
O
+
H-OH
2
+
OH
2
H
2
SO
4
/ H
2
O
O
CR NH
2
O
CR O
+
OH
_
+
O
CR NH
2
O
CR OH
+
+
H
2
O
H
2
SO
4
NH
3
(NH
4
)SO
4
Hydrolysis of Amides
Hydrolysis of Amides
Basic Solution
Acidic Solution
excess
heat
heat
Hydrolysis requires strong acid or base and heating under re#ux.
… It’s not easy !
Na
+
Na
+
: :
:
_
O
CR NH
2
O H
: :
_
:
R C NH
2
O
O H
: :
_
:
R C NH
2
O
O H
: :
:
+ NH
2
:
_
O
CR
O H
O
CR OH
: :
+
NH
2
:
_
O
CR O
: :
:
_
+ NH
3
Base-Promoted Hydrolysisof a Amide
Base-Promoted Hydrolysisof a Amide
MECHANISM
stronger base
than OH
-
, but
this step doesn’t
reverse because
of the next one
once in
a while
most often this
step reverses
because OH
-
is
a better leaving
group than NH
2
-
accumulates
NaOH
ACYLATION OF ENAMINES
ACYLATION OF ENAMINES
1)
+
R C Cl
O
RCH C R
N
CH C
R
N
C
R
R
O
+
2)
+
CH C
R
N
C
R
R
O
+
R C
O
CH C
R
R
O
+
N
H
H
3
O+
Acylation of an Enamine
Acylation of an Enamine
acyl group
was added
Cl
-
:
:
O
C
R Cl
C C
R
R R
N
:
NC
R
CR
R
C
O
R Cl
NC
R
CR
R
C
O
R
+
+
:
:
_
:
:
+
Cl
Acylation of an Enamine
Acylation of an Enamine
Mechanism
Mechanism
… continued
slow
enamine
iminium
salt
N
H
R
CH
R
C
O
R
NCCCR
O R
R
R
O
H
H
+
NCCCR
O R
R
R
O
H
H
:
:
:
:
:
+
Acylation of an Enamine
Acylation of an Enamine
Mechanism (cont)
Mechanism (cont)
NCCCR
O R
R
R
O H
H
:
:
:
+
NH
:
:
CCCR
O R
R
R
O
:
O
H
H
H
O HH
+
[...]...SUMMARY OF ACYLATION H O HOTs R C C R + N R R :N C C R R H + H2O enamine + N O :N C C R R + O R R C Cl R C C C R R R acyl group O R N R C C C R R + H3O+ O R O R C C C R R + N H MISCELLANEOUS REACTIONS OF ACID DERIVATIVES Reaction ofEsters with Organometallic Reagents O 1) ether R C O R" + 2 R' MgBr 2) H2O, acid OH R C R' + MgBr (OR") + MgBr(OH) R' cleaves the ether … reacts twice ! Reduction of Esters. .. R C O + 2 LiAlH4 R' 4 R CH2 OH + 2 LiOH + + 4 R' OH 2 Al(OH)3 Reduction ofEsters to Aldehydes O R C O R' DIBALH H2O toluene -78°C HCl O R C H + R' OH NITRILES REACTIONS AND SYNTHESIS Formation of Nitriles SN2 Reaction _ R CH2 Cl + : C N : R CH2 C N + Cl Addition to C=O +O H O H R C R :C N pH 6 R C R C N cyanohydrin Hydrolysisof Nitriles ACID SOLUTION H2SO4 R CH2 C N + H2O BASIC SOLUTION heat O R... Base-Promoted Hydrolysis of a Nitrile MECHANISM R C N 1) 2) 3) slow _ :O H : N: NaOH _ R C N: :O H _ R C OH : NH + H2O : NH R C OH : NH2 R C OH R C O _ + OH amide Tautomerism … continued Base-Promoted Hydrolysis of a Amide MECHANISM : O: 4) R C NH2 :O H _ :O H 5) _ :O : R C NH2 : O: R C : O: 6) _ + : NH2 :O H :O H R C OH NaOH _ :O: R C NH2 _ + : NH2 : O: _ R C O: + NH3 Acid-catalyzed Hydrolysis of a Nitrile... Nitrile MECHANISM + H 1) R C N 2) + + R C N H slow R C N H + :O H O H H 3) H2SO4 / H2O H R C N H :O H + H + R C N H + R C N H fast H-OH2 + R C N H + : O: H H protonated amide … continued Acid-catalyzed Hydrolysis of a Amide + :O H 4) :O H R C NH2 R C NH2 + :O H O H H :O H 5) R C NH2 + :O H H 6) :O H + R C NH3 + H-OH2 H OH2 :O H + R C NH2 H H + :O H R C NH2 :O H :O H + :O H R C OH + :NH3 :O H O R C OH + .
HYDROLYSIS REACTIONS
HYDROLYSIS REACTIONS
O
CR O R
O
CR O
+
OH
_
+
R O H
O
CR O R
O
CR OH
+
+
R O H
H
2
O
H
2
SO
4
Hydrolysis of Esters
Hydrolysis of.
Base-Promoted Hydrolysis of a Amide
Base-Promoted Hydrolysis of a Amide
MECHANISM
stronger base
than OH
-
, but
this step doesn’t
reverse because
of the