what is the name of this compound CH3-NH-CH2-CH3
a) ethylmethylnitride
b) diethylamine
c) ethylmethylnitride
d) ethylmethylnitride
e) methylethylamine
The correct answer and explanation is :
The correct name of the given compound CH₃-NH-CH₂-CH₃ is methylethylamine (option e).
Explanation:
- Understanding the Structure:
- The compound consists of an amine (-NH) group bonded to two alkyl groups: a methyl group (CH₃) and an ethyl group (CH₂CH₃).
- The presence of an amine group suggests that this compound is a secondary amine because the nitrogen is directly bonded to two carbon-containing groups.
- IUPAC Naming Rules for Amines:
- The general formula for secondary amines is R¹-NH-R², where R¹ and R² are alkyl groups.
- When naming secondary amines, the alkyl groups attached to the nitrogen are listed in alphabetical order followed by the suffix “-amine”.
- In this case, the alkyl groups are methyl (CH₃) and ethyl (CH₂CH₃).
- Alphabetically, ethyl (E) comes before methyl (M), so the correct name is methylethylamine.
- Why Other Options Are Incorrect:
- a) Ethylmethylnitride → Incorrect, because “nitride” refers to compounds containing a nitrogen anion (N³⁻), which is not the case here.
- b) Diethylamine → Incorrect, because this would mean that both groups attached to nitrogen are ethyl groups (CH₃CH₂-NH-CH₂CH₃), which is different from our compound.
- c) and d) Ethylmethylnitride → Incorrect, as explained above.
Thus, the correct answer is (e) methylethylamine.