Download IUPAC Nomenclature for Organic CHemistry and more Exercises Organic Chemistry in PDF only on Docsity!
Nomenclature
IUPAC nomenclature for organic chemistry
What is IUPAC nomenclature?
- A systematic method of naming organic chemical compounds as recommended by the International Union of Pure and Applied Chemistry (IUPAC).
- It provides an unambiguous structure.
- Official IUPAC naming recommendations are not always followed in practice, and the common or trivial name may be used.
Main chain and alkyl group
names
Main chain names Name # of Carbons Name # of Carbons meth ane 1 hex ane 6 eth ane 2 hept ane 7 prop ane 3 oct ane 8 but ane 4 non ane 9 pent ane 5 dec ane 10
Name Alkyl group names
of
Carbons Name^
of
Carbons meth yl 1 but yl 4 eth yl 2 pent yl 5 prop yl 3 Hex yl 6
Group (CH 3 ) 2 CH– (CHCH^3 ) 22 – CH CH 3 CH 2 CH(CH 3 )– (CH 3 ) 3 C– Name Isopropyl Isobutyl sec -Butyl tert -Butyl
Example
- Longest chain/main chain:
- 7 carbons (circled)
- Name: heptane
- Side chain groups:
- 1-carbon group at position 3
- Name: 3-methyl
- 2-carbon group at position 4
- Name: 4-methyl
Answer:
4-ethyl-3-methylheptane
Example
- Answer:
- 1-ethyl-2-methylcyclohexane
Answer:
cyclopropylcyclopentane
naming alkenes and alkynes
- -Ene suffix for alkene and -yne suffix for alkyne
- The root chain must be the longest chain that includes both carbon atoms of the double bond
- Number the root chain from the end nearest a double bond carbon atom (or triple bond carbon atom)
- The smaller of the two numbers designating the carbon atoms of the double/triple bond is used as the locator of alkenes/alkynes
Naming organic halides
- Same naming rules as before
- Halide substituents are named as fluoro (-F), chloror (-Cl), bromo (-Br), or iodo (-I)
Answer:
2-chloropropane
Example:
Naming Alcohols
- Drop the – ane ending of the parent compound and adding – ol
- When there’s a higher priority group present, -OH can be named as a substituent using the name hydroxy
Answer:
3-methyl-1-butanol
Example:
Naming aldehydes and ketones
- Aldehydes are named by dropping the – e of the parent name and adding – al
- The substituent name for aldehyde group is formyl
- When one or more – CHO groups are attached to the ring, the ring is named followed by carbaldehyde
- Ketones are named by dropping the – e ending and adding – one
- The substituent name is oxo
Examples
Answer:
3-oxohexanal
Examples
- 4-methyl-2- pentamine
- N-methylethanamine
- N-ethyl-N- methylpropanamine
Naming carboxylic acids
- Carboxylic acids are named by dropping the – e ending and adding the – oic acid
- The substituent name for a – COOH group is carboxy
Answer:
2-chlorocyclopentanoic acid
Example:
Examples
- Answer:
- Butanoyl chloride
Answer: Ethanoic propanoic anhydride
Answer: Methyl ethanoate (common name: acetate)
Answer: ethanamide
References
- For more detailed rules and examples including common naming rules, please consult the organic chemistry by wade textbook
- Workshop prepared by Qing Wang