Imine formation from benzaldehyde and aniline yields what kind of intermediate?

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Multiple Choice

Imine formation from benzaldehyde and aniline yields what kind of intermediate?

When a carbonyl compound like benzaldehyde reacts with a primary amine such as aniline, they undergo a condensation to form an imine (Schiff base). The lone pair on nitrogen attacks the carbonyl carbon, giving a carbinolamine intermediate that loses water to yield a C=N double bond. In this case, the imine has the carbon of the original aldehyde attached to the nitrogen that bears the aniline’s aryl group, giving Ph–CH=N–Ph. This is the characteristic imine with a C=N–Ar linkage. This is not an amide (which would require a carbonyl derivative like an acid or acyl chloride), not an aldol (which involves enolate attack on another carbonyl), and not an enamine (which forms with secondary amines).

When a carbonyl compound like benzaldehyde reacts with a primary amine such as aniline, they undergo a condensation to form an imine (Schiff base). The lone pair on nitrogen attacks the carbonyl carbon, giving a carbinolamine intermediate that loses water to yield a C=N double bond. In this case, the imine has the carbon of the original aldehyde attached to the nitrogen that bears the aniline’s aryl group, giving Ph–CH=N–Ph. This is the characteristic imine with a C=N–Ar linkage.

This is not an amide (which would require a carbonyl derivative like an acid or acyl chloride), not an aldol (which involves enolate attack on another carbonyl), and not an enamine (which forms with secondary amines).

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