Chapter 10: Q26P (page 528)

Show how you would synthesize the following alcohols by reducing appropriate carbonyl compounds.
a. Heptan-1-ol (b) Heptan-2-ol (c) 2-methylhexan-2-ol
b.

Short Answer

Expert verified

Answer

(a)

(b)

2-heptanone heptan-2-ol

(c)

2-methyl-3-hexanone 2-methyl hexan-3-ol

(d)

Step by step solution

Reduction with reducing agent

The synthesis of the compound upon reduction with reducing agentsNaBH₄is LiAIH₄thatdoes not reduce the ester and acid group whereas the ester group is reduced byLiAIH₄.

Formation of the desired product with reducing agent

(a)The heptan-1-ol is formed by the reaction of heptanal either NaBH₄ in the presence of CH₃OH or by the reaction LiAI₄ with H₃O⁺

Heptan-1-al heptan-1-ol

b. The heptan-2-ol is formed by the reaction of 2 heptanone either NaBH₄ in the presence of CH₃OH or by the reaction LiAI₄ with H₃O⁺

2-heptanone heptan-2-ol

c.The 2-methyl hexan-3 ol is formed by the reaction of 2-methyl-3-hexanone either NaBH₄ in the presence of CH₃OH or by the reaction LiAIH₄ with H₃O⁺

2-methyl-3-hexanone 2-methyl hexan-3-ol

d. In this reaction, the desired product will not be formed by the reaction of the reactant LiAIH₄ as it also reduces the ester group in addition to the ketone group whereas the NaBH₄ will reduce only the ketone group. So, this reaction is possible only with NaBH₄