Question

Which compound forms an anhydride more rapidly?

Short answer

The answer is,

Step-by-step solution

Strain

The stability of ring compounds is mainly explained on the basis of the strain of the ring present in the compound. The number of atoms in the ring increases causes an increase in the strain of the ring.

Explanation

The following compound will form an anhydride more rapidly because it forms a five-membered ring anhydride, which is less strained than the seven-membered-ring anhydride formed by the other compound. The greater stability of the five-membered-ring product causes the transition state leading to its formation to be more stable than the transition state leading to formation of the seven-membered-ring product.