Soluções para Reações de Compostos Aromáticos

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Solutions for Reactions of Aromatic Compounds
H
H
C
CH3
CH3
CH3
OH
C
H
H
H
C
CH3
CH3
CH3
C
CH3
CH3
CH3
+ BF3
(b)
+ HF
(a)
16
CH2 C
CH3
CH3
C
CH3
CH3
CH3
C
CH3
CH3
CH3
HO CHCH3
CH3
CHCH3
CH3
CH3
CH3
C
CH3
CH3
CH3
C
CH3
CH3
CH3
CH3
++ BF3(d)
+ HF
(c)
C
CH3
CH3
CH3
CH3
C CH(CH3)2
CH3
CH3
AlCl3
CH3
+
(d)
(c) No reaction: nitrobenzene is 
too deactivated for the Friedel- 
Crafts reaction to succeed.
(b)(a)
17 In (a), (b), and (d), the electrophile has rearranged.
plus poly-alkylation products
18
(a) + CH3CH2CH2CH2Br
(b) Gives desired product: activated ring plus 3° carbon in the electrophile gives para as the major product.
(c) Gives desired product plus ortho isomer; use excess bromobenzene to avoid overalkylation.
(d) No reaction; benzamide is too deactivated for a Friedel-Crafts reaction.
(e) Gives desired product: methyl is slightly activating; putting three deactivating nitro groups requires 
forcing conditions, and great care to avoid detonation! BOOM!
rearranged
rearranged
rearranged
rearranged—not the desired product
392