Organic Chemistry

Section 20.10 Designing a Synthesis VIII: Functional Group Interconversion 867

20.10 Designing a Synthesis VIII:

Functional Group Interconversion

Converting one functional group into another is called functional group interconver-

sion. Our knowledge of oxidation–reduction reactions has greatly expanded our abili-

ty to carry out functional group interconversions. For example, an aldehyde can be

converted into a primary alcohol, an alkene, a secondary alcohol, a ketone, a car-

boxylic acid, an acyl chloride, an ester, an amide, or an amine.

A ketone can be converted into an ester or an alcohol.

As the number of reactions you learn grows, so will the number of functional group

interconversions you can perform. You will also find that you have more than one

route available when you design a synthesis. The route you actually decide to use will

depend on the availability and cost of the starting materials and on the ease with which

the reactions in the synthetic pathway can be carried out.

PROBLEM 30

Add the necessary reagents over the reaction arrows.

a. b.

OH

OH

OH

OH

Br OH O

1. LiAlH 4

2. H 3 O+

O

O

O

OH

OH

RCOOH + OH

1. NaBH 4


2. H 3 O+

O

O

OH

O

H OH

1. NaBH 4


2. H 3 O+

NHCH 3

1. LiAlH 4


2. H 2 O

O

OH

O

OCH 3

O

NHCH 3

H 2 SO 4

∆

H 2 O

H 2 SO 4

H 2 CrO 4 H 2 CrO 4

O

Cl

SOCl 2 CH 3 OH

CH 3 NH 2

Tutorial:

Multistep synthesis

Tutorial:

Common terms:

oxidation–reduction reactions

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