Organic chemistry for class 11th – Functional group with it’s Priority in easy way part 02.
Organic chemistry for class 11th – Functional group with it’s Priority in easy way part 02.
Contents [hide]
- 0.1 Functional Groups & Their Priority Order in Organic Chemistry (Class 11) – Part 2
- 0.2 1. What is a Functional Group?
- 0.3 Examples of Functional Groups
- 0.4 2. Priority Order of Functional Groups in IUPAC Nomenclature
- 0.5 3. Easy Way to Remember Functional Group Priority
- 0.6 Mnemonic Trick:
- 1 4. How to Apply the Priority Order?
- 1.1 Example 1: Naming a Compound with Multiple Functional Groups
- 1.2 Example 2: Naming a Compound with Aldehyde and Ketone
- 1.3 5. Summary of Functional Group Naming
- 1.4 Organic chemistry for class 11th – Functional group with it’s Priority in easy way part 02.
- 1.5 Organic Synthesis Part 2 – Functional Group Interconversions
Functional Groups & Their Priority Order in Organic Chemistry (Class 11) – Part 2
In Organic Chemistry, functional groups are specific atoms or groups of atoms within molecules that determine their chemical properties. When naming organic compounds using IUPAC nomenclature, the priority order of functional groups is important.
1. What is a Functional Group?
A functional group is an atom or group of atoms responsible for the characteristic chemical reactions of a compound.
Examples of Functional Groups
- Alcohol (-OH) → Found in Ethanol
- Carboxylic Acid (-COOH) → Found in Acetic Acid
- Aldehyde (-CHO) → Found in Formaldehyde
- Ketone (-CO-) → Found in Acetone
- Amine (-NH₂) → Found in Amines
2. Priority Order of Functional Groups in IUPAC Nomenclature
When multiple functional groups are present in a compound, the one with the highest priority determines the suffix in the name, while others are written as prefixes.
Priority Order | Functional Group | Formula | Prefix | Suffix |
---|---|---|---|---|
1 (Highest) | Carboxylic Acid | -COOH | Carboxy- | -oic acid |
2 | Sulfonic Acid | -SO₃H | Sulfo- | -sulfonic acid |
3 | Ester | -COO- | Alkoxycarbonyl- | -oate |
4 | Acid Halide | -COCl, -COBr | Halocarbonyl- | -oyl halide |
5 | Amide | -CONH₂ | Carbamoyl- | -amide |
6 | Nitrile (Cyanide) | -CN | Cyano- | -nitrile |
7 | Aldehyde | -CHO | Formyl- | -al |
8 | Ketone | -CO- | Oxo- | -one |
9 | Alcohol | -OH | Hydroxy- | -ol |
10 | Amine | -NH₂ | Amino- | -amine |
11 | Ether | -O- | Alkoxy- | Ether (Common Name) |
12 (Lowest) | Alkene/Alkyne | C=C, C≡C | -en- / -yn- | -ene / -yne |
3. Easy Way to Remember Functional Group Priority
Mnemonic Trick:
“Can Some Easy Aliens Arrange New Alarm Kits And Alarm Everyone?”**
(Carboxylic > Sulfonic > Ester > Acid Halide > Amide > Nitrile > Aldehyde > Ketone > Alcohol > Amine > Ether)
4. How to Apply the Priority Order?
Example 1: Naming a Compound with Multiple Functional Groups
Structure:
Functional Groups Present:
- Carboxyl (-COOH)
- Hydroxyl (-OH)
Priority Order:
- Carboxyl (-COOH) is higher priority → Suffix: “-oic acid”
- Hydroxyl (-OH) is lower priority → Prefix: “Hydroxy-“
Final IUPAC Name: 3-Hydroxybutanoic acid
Example 2: Naming a Compound with Aldehyde and Ketone
Structure:
Functional Groups Present:
- Aldehyde (-CHO)
- Ketone (-CO-)
Priority Order:
- Aldehyde (-CHO) has higher priority → Suffix: “-al”
- Ketone (-CO-) is lower priority → Prefix: “Oxo-“
Final IUPAC Name: 3-Oxobutanal
5. Summary of Functional Group Naming
The highest priority functional group gets the suffix.
Other functional groups act as prefixes.
Alkenes (-C=C-) and Alkynes (-C≡C-) have the lowest priority compared to other functional groups.
Would you like more practice questions or examples?