Exercício de Química Sintética e Organica Mista (189)

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CHAPTER 8
NUCLEOPHILIC
SUBSTITUTION
SOLUTIONS TO TEXT PROBLEMS
8.1 Identify the nucleophilic anion in each reactant. The nucleophilic anion replaces bromine as a sub-
stituent on carbon.
(b) Potassium ethoxide serves as a source of the nucleophilic anion CH3CH2O
�.
(c)
(d ) Lithium azide is a source of the azide ion.
It reacts with methyl bromide to give methyl azide.
(e) The nucleophilic anion in KCN is cyanide ( ). The carbon atom is negatively charged
and is normally the site of nucleophilic reactivity.
�NCH3Br CH3C Br
�
Bromide ionMethyl cyanide
(product)
Methyl bromide
N C �
Cyanide ion
(nucleophile)
�
NC
�
N
�
N
�
N � �
�
N
�
N
�
CH3Br CH3N Br
Bromide ionMethyl azide
(product)
Methyl
bromide
Azide ion
(nucleophile)
�
N
�
N
�
N
�
CH3Br Br
Benzoate ion Methyl bromide Methyl benzoate Bromide ion
C �O
O
C �OCH3
O
� �
� �CH3CH2O CH3CH2OCH3CH3Br Br
Bromide ionEthyl methyl ether
(product)
Methyl bromideEthoxide ion
(nucleophile)
� �
184
	CHAPTER 8 NUCLEOPHILIC SUBSTITUTION