Chapter 14, Problem 14.64P

Interpretation Introduction

Interpretation:

Of the two compounds A and B, it is to be explained which one undergoes dehydration more quickly.

Concept introduction:

Dehydration is the loss of a proton and a hydroxyl group from adjacent carbons to form a product with a double bond between these carbons.

If the substrates have similar structures, the rates of their dehydration depend primarily on the stabilities of the products.

The stability of a dehydration product depends on the number of alkyl substituents on the double bond formed. The more the number of alkyl groups, the higher the stability. In cyclic compounds, if the newly formed double bond is a part of the ring, the stability of the compound depends on the aromatic character. The stability will increase in the order $\text{antiaromatic < nonaromatic < aromatic}$.