Transcript Carboxylic acid Reactions - University of Illinois at

Carboxylic Acids - Reactions
Acid-base reactions:
LDF
ion
H-bonding
O
O
-
+ NaOH
OH
+ H2O
octanoic acid
insoluble in H2O
O
O
O- O
O
O
O
O-
sodium octanoate + water
dipole
soluble
O
O
O
O
O
O
O
O
O
O
-
O
O
-
O
OO
O -O
O
Na+
O
Reactions
Reduction:
O
O
CH3 C CH2 CH2 CH2 C
6
5 4
3
2
LiAlH4
1 OH
OH
CH3 CH CH2 CH2 CH2 CH2 OH
5-oxo hexanoic acid
O
1,5- hexanediol
H
/
Pt
2
O
CH3 C CH2 CH2 CH2 C
OH
OH
O
CH3 CH CH2 CH2 CH2 C
NaBH4
5-hydroxyhexanoic acid
OH
Reactions
nucleophilic substitution
R C
O
+ H O R
OH
carboxylic acid
alcohol
H+
R C
ester
O
+ H2O
O R
condensation reaction
reverse = hydrolysis
ester + H2O
H+
carboxylic acid + alcohol
Esters
R C
from acid
O
from alcohol
O R
name = alkyl group from alcohol (yl)
acid name changed to “oate”
CH3 CH2 CH2 C
CH3 (CH2)2 C
O
methylbutanoate
O CH3
apple
O
O
pentyl butanoate
(CH2)4
CH3
peaches
Esters
R C
O
O R
H-bond acceptors O O
no H-bond donor dipole-dipole interactions
water soluble
low b.p.
Carboxylic acids
nucleophilic substitution
R
C
O
..
H N R
+
OH
carboxylic acid
R
activator
R C
O
N R
+ H2O
amide R
amine
condensation reaction
carboxylic acid + amine
amide + H2O
hydrolysis reaction
amide + H2O
carboxylic acid + amine
Amines
organic analogs of ammonia
N
H H H
N
N
H H R H R R
N
R R R
ammonia 1o amine 2o amine
all have H-bond acceptor N-
3o amine
1o and 2o have H-bond donor H+
high b.p.
CH3 OH
H N CH3 electronegativity
liquid at room T
O >N
H gas at room T
Amines
nomenclature
1. Name and alphabetize R groups
and add “amine”
H N CH3 methylamine
H
H N CH3
CH2 CH3
H3C N CH3
CH2 CH3
1o
ethyl methylamine 2o
ethyl dimethylamine 3o low b.p.
Amines
weak bases
H
R N
H
+ H2O
H
+][OH-]
[R-NH
Kb =
3
[R-NH2]
R N H
+ OH-
H
smaller Kb
weaker base
Amines
nucleophilic substitution
activator
R
C
O
RH NN RH
H
RR
+
OH
carboxylic acid
amine
123oo amine
O
OO ++H
2O
H
2
no
RRreaction
CC
NN RH
amide
amide
Condensation reaction
RR
Amides
O
O
R C
R
N R
R
C
N
R
R
very high b.p.
C-O and C-N double bond character
no rotation about C-O or C-N bonds
molecule is flat and rigid structure of proteins