MHT CET Medical202624 April 2026Evening ShiftChemistryAldehydes and KetonesActual
What is the product obtained when Pent-3-enenitrile is treated with DIBAL-H followed by acid hydrolysis?
Options
- ACH ₃ -CH=CH-CH ₂ -CHO
- BCH ₃ -(CH ₂)₂ -CH ₂ -CHO
- CCH ₃ -CH=CH-CH ₂ -COOH
- DCH ₃ -(CH ₂)₂ -CH ₂ OH
Correct answer
A. CH ₃ -CH=CH-CH ₂ -CHO
Step-by-step solution
The structure of Pent-3-enenitrile is CH ₃ -CH=CH-CH ₂ -CN . DIBAL-H (Diisobutylaluminium hydride) is a selective reducing agent that reduces nitriles to imines. Upon subsequent acid hydrolysis, the imine is converted to an aldehyde. DIBAL-H does not reduce isolated carbon-carbon double bonds. Therefore, the -CN group is converted to a -CHO group, while the double bond remains intact. The product formed is Pent-3-enal, which has the structure CH ₃ -CH=CH-CH ₂ -CHO . Answer: CH ₃ -CH=CH-CH ₂ -CHO