question 13\nwhat stretching frequencies (in cm⁻¹) are present in the structure below?\n1640\n1715\n2250
question 13\nwhat stretching frequencies (in cm⁻¹) are present in the structure below?\n1640\n1715\n2250
Answer
Explanation:
Step1: Identify the functional group
The structure has a carbon - carbon double bond ($C = C$).
Step2: Recall stretching frequencies
The stretching frequency of a non - conjugated $C = C$ bond is around 1640 - 1680 $cm^{-1}$. A carbonyl ($C=O$) stretch is around 1715 $cm^{-1}$ and a $C\equiv C$ stretch is around 2200 - 2260 $cm^{-1}$. Since our structure has a $C = C$ bond, the relevant stretching frequency is around 1640 $cm^{-1}$.
Answer:
1640