There are two primary amines possible for the compound C3H9N.
Understanding Primary Amines and Isomerism
A primary amine is an organic compound where the nitrogen atom is bonded to one carbon atom and two hydrogen atoms (forming an -NH2 group). Isomers are compounds that have the same molecular formula but different structural arrangements of atoms. For the molecular formula C3H9N, we need to identify all possible unique structures where an -NH2 group is attached to a three-carbon chain.
The molecular formula C3H9N has a hydrogen deficiency index (HDI) of zero, indicating that it is a saturated, acyclic compound. This means all bonds are single bonds, and there are no rings or double/triple bonds.
Isomeric Primary Amines of C3H9N
To determine the primary amines, we first consider the possible arrangements of the three carbon atoms and then attach the -NH2 group. There are two distinct carbon chain skeletons for three carbons:
- A straight chain: Propane backbone (C-C-C)
- A branched chain: Isopropane backbone (C-C(C)-C, but for 3 carbons, this is effectively the same as a straight chain if considering the placement of a functional group, specifically the middle carbon is unique.)
Attaching the -NH2 group to these skeletons yields the following primary amine isomers:
- n-Propylamine (1-aminopropane): In this isomer, the amino group (-NH2) is attached to an end carbon of a straight three-carbon chain.
- Structure: CH3-CH2-CH2-NH2
- Isopropylamine (2-aminopropane): Here, the amino group (-NH2) is attached to the middle carbon of a three-carbon chain.
- Structure: CH3-CH(NH2)-CH3
These two structures are distinct and cannot be superimposed, confirming they are unique isomers.
Here is a summary of the primary amine isomers for C3H9N:
| Isomer Name | IUPAC Name | Structure | Type of Amine |
|---|---|---|---|
| n-Propylamine | 1-aminopropane | CH3CH2CH2NH2 | Primary |
| Isopropylamine | 2-aminopropane | CH3CH(NH2)CH3 | Primary |
These are the only two ways to attach an -NH2 group to a three-carbon saturated chain such that the nitrogen is bonded to only one carbon, thus fulfilling the definition of a primary amine.
