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C. Soulie / Tetrahedron 57 (2001) 1035±1040
1039
®tted with a re¯ux condenser and a nitrogen purge line, were
placed 1b (4.6 g, 16.6 mmol) and silver tri¯uoroacetate
(3.66 g, 16.6 mmol). A solution of diiodide in chloroform
(4.3 g of I2, 16.6 mmol in 50 mL of chloroform) was then
added dropwise. The deep purple diiodide solution turned
light-yellow rapidly when reacting. After 2 h, silver iodide
was ®ltered out and the solution washed with water. The
product was puri®ed on a silica gel column (eluent:
dichloromethane) and on a second one (eluent: dichloro-
methane/cyclohexane) yielding 2b in 60% yield as a yellow
liquid. 1H NMR down®eld from TMS (CDCl3): d: 7.5 (1H,
d, J5 Hz, Ar), 7.0 (1H, dd, J5, 9 Hz, Ar), 6.7 (1H, d,
J9 Hz, Ar), 3.8 (3H, s, OCH3), 2.4 (2H, t, Ar±CH2), 1.6±
0.8 (15H, m, C7H15). 13C NMR (CDCl3): d: 156.0 (ArC1),
139.1 (ArC5), 137.1 (ArC6), 129.2 (ArC4), 110.6 (ArC3),
85.7 (ArC2), 56.3 (OCH3), 34.4 (Ar±CH2), 31.8±14.0
(C7H15). IR (KBr): 1280m (nC±H, OMe), 1254s (nC±O),
553w (nC±I). TLC (SiO2, CH2Cl2/C6H12, v/v: 1/1): Rf0.76.
5.1.5. 5-Dodecyl-50-octyl-2,20-dimethoxydianiline (6bc).
In a three-necked ¯ask, ®tted with a condenser and a
nitrogen purge line, 5-dodecyl-50-octyl-2,20-dimethoxy-
diacetanilide 5bc (0.938 g, 1.7 mmol), freshly sublimated
potassium tert-butylate (1.257 g, 11.22 mmol) and 15 mL
of dry THF were introduced. The apparatus was purged
and 66 mL of distilled water (3.4 mmol) were added. The
mixture was re¯uxed 3 h and then cooled on an ice bath. The
cold mixture was added with ice, extracted with diethylether
and washed with water. The product was puri®ed on a silica
gel column yielding the desired aniline 6bc quantitatively
(eluent: dichloromethane). It is noteworthy that the reaction
can be run with standard THF. In this case, catalytic amount
1
of water is not required. H NMR down®eld from TMS
(CDCl3): d: 7.15 (2H, d, J1.5 Hz, Ar), 6.8 (2H, d, J
7.5 Hz, Ar), 6.6 (2H, dd, J1.5, 7.5 Hz, Ar), 3.75 (6H, s,
OCH3), 2.45 (4H, t, Ar±CH2), 1.6±0.8 (38H, m,
C7H151C11H23), 1.35 (1H, s, NH). 13C NMR (CDCl3): d:
0
147.0 (ArC2C2 ), 135.1 (ArC5C5 ), 132.1 (ArC1C1 ), 119.5
0
0
0
0
0
5.1.3. 2-Methoxy-5-alkylacetanilides (4a±c). To a solution
of 2-methoxy-4-dodecylaniline 3c (3.63 g, 12.5 mmol) in
50 mL of diethylether and 100 mL of distilled water were
added 4 portions (2.5 mL each, 2.3 equiv.) of acetic
anhydride over a total period of 1 h. The reaction was
followed by SiO2 TLC. The product was extracted with
dichloromethane, washed with water, puri®ed on a silica
gel column (eluent: dichloromethane) and recrystallized
from pentane. 4a: 78% yield, beige plate-like crystals; 4b:
86% yield, light-pink crystals; 4c: 95% yield, white powder.
1H NMR down®eld from TMS (CDCl3): d: 8.2 (1H, s, Ar),
7.7 (1H, s, NH), 6.7 (2H, m, Ar), 3.8 (3H, s, OCH3), 2.5 (2H,
t, Ar±CH2), 2.2 (3H, s, NCOCH3), 1.3±0.9 (23H, m,
C11H23). 13C NMR (CDCl3): d: 168.0 (CO), 145.5 (ArC2),
135.7 (ArC5), 127.3 (ArC1), 123.0 (ArC6), 119.6 (ArC4),
109.4 (ArC3), 55.5 (OCH3), 35.4±14.0 (C12H25), 22.5
(COCH3). IR (KBr): 3276s (nN±H), 1668s (nCvO, amide II).
TLC (SiO2, dichloromethane): Rf0.55.
(ArC4C4 ), 115.7 (ArC6C6 ), 110.3 (ArC3C3 ), 55.6 (OCH3),
35.4 (Ar±CH2), 31.8±14.2 (C111C7). IR (KBr): 3424m
(nN±H), no band in the 1700±1650 region. TLC (SiO2,
dichloromethane): Rf0.90.
5.1.6. (5-Butyl-50-dodecyl-500-octyl-2,20,200-trimethoxytri-
phenyl)amine (7abc). In a three-necked ¯ask, ®tted with a
condenser and a nitrogen purge line, were placed 5-dodecyl-
50-octyl-2,20-dimethoxydianiline 6bc (0.169 g, 0.332
mmol), 2-iodo-4-butylanisole 2a (0.137 g, 0.397 mmol),
spongy copper powder (0.044 g, 0.681 mmol), caesium
carbonate (0.258 g, 0.791 mmol), 18-crown-6 (0.010 g,
0.039 mmol) and 5 mL of diglyme. The reaction mixture
was re¯uxed for 70 h, then ®ltered on a Buchner funnel
and washed with hot diglyme. The diglyme was removed
by distillation under vacuum and the residue puri®ed on a
silica preparative TLC plate (eluent: dichloromethane). The
desired product was obtained as light-brown viscous liquid
1
in 74% yield. H NMR down®eld from TMS (CDCl3): d:
5.1.4. 5-Alkyl-50-alkyl-2,20-dimethoxydiacetanilides (5ab±
bc). In a three-necked ¯ask, ®tted with a condenser and a
nitrogen purge line, were placed 2-methoxy-5-dodecyl-
acetanilide 4c (1.2 g, 3.6 mmol), 2-iodo-4-octylanisole 2b
(1.5 g, 4.32 mmol), spongy copper powder (0.482 g,
7.41 mmol), caesium carbonate (2.814 g, 8.64 mmol),
18-crown-6 (0.105 g, 0.432 mmol) and 10 mL of diglyme.
The reaction mixture was re¯uxed for at least 24 h, then
®ltered on a Buchner funnel and washed with hot diglyme.
The diglyme was removed by distillation under vacuum
(bp60.58C/15 mmHg). The residue was puri®ed on a silica
gel column (eluent: dichloromethane). 5ab: 56% yield,
brown liquid; 5bc: 73% yield, brown liquid. 1H NMR down-
®eld from TMS (CDCl3): d: 7.2±7.0 (4H, m, Ar), 6.9 (2H,
m, Ar), 3.9 (6H, 2s, OCH3), 2.4 (4H, 2t, Ar±CH2), 2.0 (3H,
s, NCOCH3), 1.45±0.8 (38H, m, C7H151C11H23). 13C NMR
6.75 (3H, dd, J1.5, 7.5 Hz, Ar), 6.65 (3H, d, J7.5 Hz,
Ar), 6.5 (3H, d, J1.5 Hz, Ar), 3.45 (9H, s, OCH3), 2.35
(6H, t, Ar±CH2), 1.4±0.8 (45H, m, C3H71C7H151C11H23).
13C NMR (CDCl3): d: 151.0 (ArC2C2 C2 ), 137.3
0
00
0
00
0
00
0
00
(ArC5C5 C5 ), 134.9 (ArC1C1 C1 ), 124.4 (ArC6C6 C6 ),
0
00
0
00
122.9 (ArC4C4 C4 ), 112.2 (ArC3C3 C3 ), 55.6 (OCH3),
34.9 (Ar±CH2), 31.8±13.8 (C111C71C3). IR (KBr): no
band in the 3500±3300 region. TLC (SiO2, dichloro-
methane): Rf0.65.
5.1.7.
(5-Butyl-50-dodecyl-500-octyl-2,20,200-triphenol)-
amine (8abc). In a three-necked ¯ask, ®tted with a con-
denser and a nitrogen purge line, were placed (5-butyl-50-
dodecyl-500-octyl-2,20,200-trimethoxytriphenyl)amine 7abc
(0.165 g, 0.246 mmol), anhydrous aluminum chloride
(0.100 g, 0.741 mmol) and 10 mL of dry toluene. The solu-
tion was re¯uxed for at least 4 h and then hydrolyzed with
10 mL of aqueous hydrochloric acid (10%, v/v). The
organic part was washed with water and separated on a silica
preparative TLC plate (eluent: dichloromethane). The
desired product was obtained in 75% yield as a light-
brown viscous liquid. 1H NMR down®eld from TMS
(CDCl3): d: 6.8 (3H, dd, J1.5, 7.5 Hz, Ar), 6.7 (3H, d,
J7.5 Hz, Ar), 6.6 (3H, d, J1.5 Hz, Ar), 5.45 (3H, large
peak, OH), 2.4 (6H, t, Ar±CH2), 1.5±0.8 (45H, m,
0
(CDCl3): d: 172.4 (CO), 153.9±153.7 (ArC2C2 ), 136.5±
0
136.2 (ArC5C5 ), 133.1±132.3 (ArC4C4 ), 130.4±130.0
0
0
(ArC6C6 ),
0
(ArC1C1 ),
129.5±129.0
112.9±112.5
0
(ArC3C3 ), 56.7±56.3 (OCH3), 35.8±35.6 (Ar±CH2),
32.8±14.9 (C111C7), 22.8 (COCH3). It is noteworthy
that all peaks are double (except for the COCH3 frag-
ment) thus showing the embedded rotation of amides. IR
(KBr): 1684s (nCvO, amide III). TLC (SiO2, dichloromethane):
Rf0.15.