Question

what stretching frequencies (in cm^-1) are present in the structure below? o 3300 none of these all of these 1685

Explanation:

Step1: Identify functional groups

The structure has an amide ($-CONH_2$) and a cyclo - hexane ring. The amide group has characteristic stretching frequencies.

Step2: Recall amide stretching frequencies

The $N - H$ stretching of primary amides occurs around 3300 - 3500 $cm^{-1}$ and the $C=O$ stretching of amides occurs around 1630 - 1680 $cm^{-1}$.

Step3: Analyze options

3300 $cm^{-1}$ is in the range of $N - H$ stretching of primary amides and 1685 $cm^{-1}$ is close to the $C=O$ stretching range of amides.

Answer:

all of these