MolSynapsequestion bank

MolSynapse / Question bank / Organic Reaction Mechanisms I: Nucleophiles and Carbonyl Addition / Formation of acetals, imines and enamines

JEE Main levelSingle correct optionDifficulty 2 of 3o1136

In acid-catalysed formation of an acetal from an aldehyde and methanol, the species that is attacked by the second molecule of $CH X_{3} OH$ is the

Acarbanion at the alpha carbon
Bfree radical formed by homolysis of C-O
Calkoxy-stabilised carbocation (oxocarbenium ion)
Dhemiacetal alkoxide ion

Answer: C

After the hemiacetal forms, its OH is protonated and leaves as water, giving

R - CH = O X^{+} - CH X_{3}

. This oxocarbenium ion is stabilised by lone-pair donation from oxygen and is a strong electrophile for the second alcohol molecule.

Practice Organic Reaction Mechanisms I: Nucleophiles and Carbonyl Addition More on Formation of acetals, imines and enamines

Previous questionNext question

More questions on Formation of acetals, imines and enamines