Carboxylic Acids and Carboxylic Acid Derivatives Chapter 14.
SCH 206 Carboxylic acids, Carboxylic acid derivatives · PDF fileCarboxylic acids, Carboxylic...
Transcript of SCH 206 Carboxylic acids, Carboxylic acid derivatives · PDF fileCarboxylic acids, Carboxylic...
SCH 206
Dr. Solomon DereseDr. Solomon Derese 1
Carboxylic acids, Carboxylic acid derivatives and Nitriles
SCH 206
Dr. Solomon Derese 2
Nomenclature of carboxylic acids and their derivatives and nitriles
Nomenclature of carboxylic acids
The IUPAC names of carboxylic acids are obtained bydropping the final e of the corresponding hydrocarbon andadding –oic acid. Note that the carboxyl carbon atom isalways C-1.Examples
Methanoic acid Ethanoic acid
SCH 206
Dr. Solomon Derese
H O
O
H CH3 O
O
H
Examples
Formic acid Acetic acid(Ant bite) (Vinegar)
O
O
H
Caproic acid (Aroma of goats)3
Acetum, Latin: vinegarFormica, Latin: ant
Caper, Latin: goat
Most simple carboxylic acids have common namesthat are more widely used than their IUPAC names.
Dirty socks
SCH 206
Dr. Solomon Derese
O
O
H 4-Hexenoic acid1
23
4
56
Cyclic carboxylic acids are named by using the suffixcarboxylic acid.
ExamplesOO
H
Br
3-Bromocyclohexanecarboxylic acid
4
SCH 206
Dr. Solomon Derese
OOH
O
O O
H
OOH
2-Cyclopentenecarboxylic acid
Benzenecarboxylic acid
Benzoyl
m-Benzoylbenzoic acid
(Benzoic acid)
5
SCH 206
Dr. Solomon Derese
Compounds with two carbonyl groups are distinguished bythe suffix –dioic acid or dicarboxylic acid asappropriate. The final e in the base name of thecorresponding hydrocarbon is retained.Examples
O
O
H
O
OH Butanedioic acid (Succinic acid)
6
SCH 206
Dr. Solomon Derese
O
H
O
O
O
H
1,2-Benzenedicarboxylic acid (Phthalic acid)
O
O
H
O
OH
OH
OH(2R,3R)-2,3-Dihydroxybutanedioic acid
1
2 3
1
23
7
Revise the R/S designation of sp3 hybridizedcarbons you learnt in SCH 102.
SCH 206
Dr. Solomon Derese
I. Acyl chlorides are named by dropping –ic acid from thename of the corresponding carboxylic acid and thenadding –yl chloride
H Cl
O
Cl
OCl
O
Formyl chloride Acetyl chloride Benzoyl chlorideII. Or replacing the carbocylic acid ending with carbocylic
chloride for cyclic acid chlorides.
8
Nomenclature of acyl chlorides
Cl
O
Cyclohexanecarbonyl chloride
SCH 206
Dr. Solomon Derese
Named by dropping the word acid (From the correspondingcarboxylic acid) and replacing it with – anhydride.
Nomenclature of Acid anhydrides Symmetrical anhydrides
9
Acetic anhydride Heptanoic anhydride
Mixed anhydrides
Named by giving in alphabetical order, the first part of thenames of the two acids followed by “anhydride”.
SCH 206
Dr. Solomon Derese 10
Acetic propanoic anhydride
Benzoic butanoic anhydride
Acetic Propanoic
Butanoic Benzoic
SCH 206
Dr. Solomon Derese
IUPAC names for esters are derived by first citing the groupderived from the alcohol, followed by the group derivedfrom the carboxylic acid (with the ending –ate or –oate).They are named as alkyl carboxylates - Alkyl from thealcohol, Carboxylate from the carboxylic acid precursor.
Nomenclature of esters
11
O
O
Ethyl acetate (Ethyl ethanoate)
Methyl p-chlorobenzoate
1,1-Dimethylethyl E-2-butenoate
SCH 206
Dr. Solomon Derese 12
Nomenclature of amidesAmides with an unsubstituted – NH2 group are named byreplacing the – oic acid ending with amide, or by replacingthe – carboxylic acid ending with – carboxamide of thecorresponding carboxylic acid.
Methyl cyclopentanecarboxylate
SCH 206
Dr. Solomon Derese 13
If the nitrogen atom is further substituted, the compound isnamed by identifying the substituent and then citing thebase name. Note that the substituents are preceded by theletter N to identify them as being directly attached to N.Examples
O
N
N,N-Dimethyl propanamide
SCH 206
Dr. Solomon Derese 14
Simple nitriles are named by adding the suffix – nitrile tothe name of the corresponding hydrocarbon. Note thatthe nitrile carbon is taken as C-1.
Nomenclature of nitriles
SCH 206
Dr. Solomon Derese 15
Cyclic nitriles are usually considered as derived fromcarboxylic acids, and are named either by replacing –ic acid/-oic acid with – onitrile.
SCH 206
Dr. Solomon Derese 16
Read the attached notes for rules on nomenclatureof polyfunctional organic compounds.
Nomenclature of carboxylic acids and derivatives.Attached separately.
Assignment 18