MolSynapsequestion bank

MolSynapse / Question bank / General Organic Chemistry II: Acids and Bases / Most acidic hydrogen in drawn molecules

JEE Main levelOne or more correct optionsDifficulty 2 of 3g2253

The compound shown is a cyclic 1,3-diketone. Select ALL the correct statements.

AIts acidic hydrogen is more acidic than that of acetone.
BThe hydrogens on the carbon between the two C=O groups are the most acidic.
CThe conjugate base has charge delocalised over three atoms.
DThe CH3 hydrogens are comparably acidic to the C2 hydrogens.

Answer: A, B, C

The compound is 5,5-dimethylcyclohexane-1,3-dione (dimedone). Its C2 hydrogens (pKa about 5.2) are the most acidic; the anion has its charge delocalised over C2 and both oxygens, and it is far more acidic than acetone (19). The gem-dimethyl hydrogens are not acidic (pKa above 40).

Practice General Organic Chemistry II: Acids and Bases More on Most acidic hydrogen in drawn molecules

Previous questionNext question

More questions on Most acidic hydrogen in drawn molecules

Which hydrogens of the compound shown are the most acidic? NEET level
The structures shown are four anions, each obtained from the molecule drawn by removing one proton. Which anion results from loss of the mos... JEE Main level
Which hydrogens of the compound shown are the most acidic? JEE Main level
Which hydrogen of the compound shown is the most acidic? JEE Main level
Which hydrogen atoms of the compound shown are the most acidic? JEE Main level
In the compound shown, count the sets of chemically equivalent hydrogen atoms whose pKa is below 12. Use these approximate values: carboxyli... JEE Advanced level