Question

question 12
0.5 pts
what is the stretching frequency (in cm⁻¹) of the following carbonyl?
none of the above
1775
1715
1745

Explanation:

Step1: Identify the carbonyl type

The given compound is a cyclic ester (a lactone). Cyclic esters have characteristic carbon - oxygen double - bond (carbonyl) stretching frequencies.

Step2: Recall the frequency range for cyclic esters

The carbonyl stretching frequency for a five - membered cyclic ester (a γ - lactone) is around 1775 cm⁻¹.

Answer:

1775