Question

question 16
what is the stretching frequency (in cm⁻¹) of the following carbonyl?
1655
1685

Explanation:

Step1: Identify the carbon - amide group

The given compound has a carbon - amide group (amide) with an adjacent double bond (conjugated system).

Step2: Recall amide carbonyl stretching frequency range

Conjugated amides have carbonyl stretching frequencies in the range of 1630 - 1680 cm⁻¹.

Step3: Select the appropriate value

Among the given options, 1655 cm⁻¹ lies within the typical range for a conjugated amide carbonyl stretching frequency.

Answer:

1655