Q58E - Chemistry (OpenStax)

Question

Write the Lewis structures of all isomers with the formula \({C_3}{H_7}ON \) that contain an amide linkage. 

Step-by-Step Solution

Answer

Propionamide, N-methylacetamide, N,N-dimethylformamide, N-ethylformamide 

Step 1: Amide

An amide is a carboxylic acid derivative that contains amide linkage.

Instead of the \( - OH\) group in \( - COOH\), it has an \( - N{H_2}\) group at its place and is available for forming bonds with alkyl chains.

Step 2: The first isomer

The first amide structure is propionamide.

Its structure consists of an acyl chain that contains three carbon atoms and an amide group. Nitrogen doesn't share any N-C bonds in this case.

Step 3: The second isomer

The second amide structure is N-methylacetamide.

Acetamide indicates that it comes from acetic acid, which has 2 carbon atoms, and that instead of COOH, there is an amide group.

Also, N- methyl in the name suggests that there is a methyl group bonded directly to the amide nitrogen atom.

Step 4: The third isomer

The third amide structure is \(N,N\)-dimethylformamide.

Formamide indicates that it comes from formic acid, which has 1 carbon atom, and that instead of \(COOH\) , there is an amide group.

Also, N,N-dimethyl in the name suggests that there are two methyl groups bonded directly to the amide nitrogen atom.

             N,N-dimethylformamide

Step 5: The fourth isomer

The fourth isomer is N-ethylformamide.

Its structure is as shown below:

              N-ethylformamide