Chemistry - STRUCTURAL ISOMERISM Question with Solution | TestHub

Under OD⁻/D₂O only the alpha C-H protons of the two carbonyls and the O-H proton exchange. The alpha positions are : the CH₂ between the two C=O groups (2H, doubly activated), the outer CH₂ alpha to the upper C=O (2H), and the ring-junction CH alpha to the lower C=O (1H). The O-H proton exchanges instantly. Total : 5 C-H protons + 1 O-H proton = 6 hydrogens exchanged; all other ring hydrogens (not alpha to a carbonyl) stay in place.