Organic Chemistry

Problems 881

60. Identify A through O:


61. Show how the following compounds could be prepared, using only the indicated starting material as the source of carbon:

a.

b.

c.

d.

62. A primary alcohol can be oxidized only as far as the aldehyde stage if the alcohol is first treated with tosyl chloride (TsCl) and the
    resulting tosylate is allowed to react with dimethyl sulfoxide (DMSO). Propose a mechanism for this reaction. (Hint:See
    Section 20.2.)


63. Identify the alkene that gives each of the following products upon ozonolysis, followed by treatment with dimethyl sulfide:

a. b.

64. Propose a mechanism to explain how dimethyl sulfoxide and oxalyl chloride react to form the dimethylchlorosulfonium ion used
    as the oxidizing agent in the Swern oxidation.

CH 3 CH 3 +

O

S

O

C

O

Cl CCl + CO 2 + CO+ Cl−

dimethyl sulfoxide

CH 3 CH 3

Cl

S

dimethylchloro-

sulfonium ion

oxalyl chloride

+

O

H

O O

HCH

O

+

O

O

H

O

O

O

CH 3 CH 2 CH 2 CH 2 OH

TsCl

pyridine

CH 3 CH 2 CH 2 CH 2 OTs

DMSO

CH 3 CH 2 CH 2 CH

CH 3 CH 2 CH from two molecules of ethane

O

CH 3 C CHCH 3 from propane and any molecule with two carbon atoms

O CH 3

CH 3 CH CCH 3 using propane as the only source of carbon

CH 3

CH 3 CCH 3 from

O

CH 3 CHCH 3

CH 3

Br 2

h

H+

CH 3 CH 2 OH

excess

CH 3 CH 2 NH 2

HO− Br 2

H 2 CrO 4

H 3 O+

AB

H 2 CrO 4

C + D

F

E

1. O 3 , – 78 °C


2. Zn, H 2 O


3. BH 3 /THF


4. H 2 O 2 , HO−

I

SOCl 2

J

CH 3 OH

KL

HBr

MN

H

1. Mg, Et 2 O


2. ethylene oxide
   O

G

CH 3

HOOC COOH

HH

C

maleic acid

C

HOOC H

H COOH

C

fumaric acid

C

COOH

CHOH

CHOH

COOH

tartaric acid

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