Which of the following carbonyl compounds yields a secondary alcohol upon reduction with l… — JAMB UTME

Which of the following carbonyl compounds yields a secondary alcohol upon reduction with lithium tetrahydridoaluminate(III) ( $LiAlH_4$ )?

Propanone yields a secondary alcohol (propan-2-ol) when reduced by lithium tetrahydridoaluminate(III).

Propanone is a ketone (alkanone). When reduced with lithium tetrahydridoaluminate(III) (

LiAlH_4

), the carbonyl carbon (

C=O

) is converted to a secondary alcohol group (

-CH(OH)-

). Specifically, propanone (

CH_3COCH_3

) is reduced to propan-2-ol (

CH_3CH(OH)CH_3

), which contains a carbon atom bonded to two other carbon atoms and the hydroxyl group.

Identify the functional groups of the given carbonyl compounds.

Propanone (

CH_3COCH_3

) is a ketone (alkanone), whereas ethanal (

CH_3CHO

), butanal (

CH_3CH_2CH_2CHO

), and methanal (

HCHO

) are aldehydes (alkanals).

Alkanals and alkanones exhibit distinct reduction behaviors based on the position of the carbonyl group (

C=O

Apply the general reduction reaction rules for alkanals and alkanones using

LiAlH_4

Reduction of an alkanal (

R-CHO

) produces a primary alcohol (

R-CH_2OH

). Reduction of an alkanone (

R-CO-R'

) produces a secondary alcohol (

R-CH(OH)-R'

The hydride ion (

H^-

) adds to the carbonyl carbon atom, converting the ketone group into a secondary hydroxyl group.

Determine which compound forms a secondary alcohol.

Propanone (

CH_3COCH_3

) is reduced to propan-2-ol (

CH_3CH(OH)CH_3

), which is a secondary alcohol.

Propan-2-ol has the hydroxyl-bearing carbon attached to two other carbon atoms, fitting the definition of a secondary alcohol.

Reduction of Alkanals and Alkanones

Question