COMEDK2024Evening ShiftChemistryAldehydes and KetonesActual
What is/are the product/s formed when Benzaldehyde and Ethanal react in presence of dil. NaOH followed by heating the intermediate product formed?
Options
- AOnly product is But-2-enal
- BOnly product is 2-Phenylprop-2-enal
- C2-Methylpent-2-enal & But-2-enal
- D3-Phenylprop-2-enal & But-2-enal
Correct answer
D. 3-Phenylprop-2-enal & But-2-enal
Step-by-step solution
The reaction between Benzaldehyde ( C₆H₅CHO ) and Ethanal ( CH₃CHO ) in the presence of dilute NaOH is a crossed aldol condensation. Since Benzaldehyde has no -hydrogen, it acts as the electrophile, while Ethanal acts as the nucleophile. The initial aldol addition product is C₆H₅CH(OH)CH₂CHO (3-hydroxy-3-phenylpropanal). Upon heating, this undergoes dehydration to form 3-phenylprop-2-enal (cinnamaldehyde). Additionally, Ethanal can undergo self-aldol condensation in the presence of dilute NaOH to form CH₃CH(OH)CH₂C