Pentanedial (glutaraldehyde) is treated with excess HCN, followed by complete acidic hydrolysis. The stereochemical composition of the final product mixture is:

Step-by-step solution

Pentanedial is an achiral dialdehyde with the structure OHC-CH ₂ -CH ₂ -CH ₂ -CHO . Step (i): Reaction with excess HCN leads to nucleophilic addition at both aldehyde groups, forming a bis-cyanohydrin. Step (ii): Complete acidic hydrolysis converts both -CN groups to -COOH groups, yielding 2,6-dihydroxyheptanedioic acid, HOOC-CH(OH)-CH ₂ -CH ₂ -CH ₂ -CH(OH)-COOH . This molecule has two structurally identical chiral centers at C2 and C6. For a molecule with two identical chiral centers, the possible stereoisomers ar