NEET2018ChemistryAlcohols Phenols and EthersActual
Which of the following is the correct sequence of step involved in the mechanism of Cannizzaro reaction?
Options
- ANucleophilic attack, transfer of H ⁻ and transfer of H ⁺
- BTransfer of H ⁻ , transfer of H ⁺ and nucleophilic attack
- CTransfer of H ⁺ , nucleophilic attack and transfer of H ⁻
- DElectrophilic attack by OH ⁻ , transfer of H ⁺ and transfer of H ⁻
Correct answer
A. Nucleophilic attack, transfer of H ⁻ and transfer of H ⁺
Step-by-step solution
Cannizzaro reaction involves the aldehydes which do not have an -hydrogen atom, undergo self oxidation and reduction reaction on heating with conc. alkali. HCHO + HCHO conc. KOH CH ₃ OH + HCOO ⁻ Mechanism Step I Attack of nucleophile OH ⁻ to the carbonyl carbon. Step II Transfer of hydride ion from anion I to second molecule of aldehyde and finally rapid transfer of proton takes place.