Question

Given both dimethyl malonate and meldrum acid. The pKa of dimethyl malonate is 13 while the pKa of meldrum's acid is 4.97. Answer the Following questions regarding these two compounds.

1. Indicate the most acidic proton on each structure and draw the conjugate base of each compound.

2. Using the two compounds provided and the two conjugate base pairs you drew in part 1, draw an acid-base equilibrium reaction that favors formation of the products. Label each compound in this reactio as an acid, base, conjugate acid, or conjugate base.

3. Dimethyl malonate and meldrums acid are fairly close in structure. What accounts for the large difference in their acidity?

Answer 1

1.

2.

3.

Meldrum acid is stronger acid than domethyl malonate. In meldrum acid, the H atoms of methylene groups can be relatively more easily eliminated because the corformation of chari form of cyclcic 6 member ring is more suitable so that the lone pair on adjacent O atom are in close proximity to the H atom to be removed.