1908
T. Toyoshima et al. / Tetrahedron 69 (2013) 1904e1911
NMR (300 MHz, CDCl3):
d
10.81 (2H, s), 8.11 (2H, d, J¼7.7 Hz), 7.57
Anal. Calcd for C22H15Br2Cl$1/4H2O: C, 55.15; H, 3.26. Found: C,
55.28; H, 3.24.
(1H, t, J¼7.7 Hz), 2.79 (2H, t, J¼7.2 Hz), 1.52e1.30 (4H, m), 0.82 (3H,
t, J¼7.3 Hz); 13C NMR (75 MHz, CDCl3):
d 191.6, 142.6, 138.7, 133.7,
129.3, 40.1, 31.5, 21.7, 13.5. Anal. Calcd for C12H14O2S$1/5H2O: C,
4.10. 1,3-Bis[2-(2-bromophenyl)ethenyl]-2-butoxybenzene (5e)
63.80; H, 6.42; Found: C, 63.87; H, 6.23; N 0.08.
The same procedure for 5g was used, but using 2-butoxy iso-
phthalaldehyde (1.2816 g, 6.2141 mmol) and corresponding other
reagents. A 2.5100 g of 5e was obtained (4.8997 mmol, 79%).
Compound 5e: white semisolid; 1H NMR (300 MHz, CDCl3):
4.6. 2-Dodecylthioisophthalaldehyde (2k)
The same procedure for 2i was used, but using 2-chloroisoph-
thalaldehyde17 (961.2 mg, 5.702 mmol), 1-dodecanethiol (1.35 ml,
5.67 mmol), and K2CO3 (1.00 g, 7.23 mmol) in DMF (20 ml) afforded
2k (1.4996 g, 4.48 mmol, 79%). Compound 2k: yellow oil; 1H NMR
d
7.80e6.50 (15H, m), 4.80e4.10 (2H, m), 1.85e1.57 (4H, m),
1.10e0.90 (3H, m); 13C NMR (75 MHz, CDCl3):
d
137.7, 137.6, 133.1,
132.7, 130.9, 130.7, 130.3, 130.2, 123.0, 129.8, 128.8, 128.7, 128.6,
128.2, 127.6, 127.1, 127.0, 126.9, 126.7, 126.1, 124.1, 123.7, 122.9, 74.5,
74.1, 32.5, 32.4, 19.4, 14.0. The complexity of the spectrum indicated
a mixture of the (E, E)-, (E, Z)-, and (Z, Z)-isomers. FABMS m/z 513
[MþH]þ (68), 457 (45), 376 (50); IR (cmꢀ1): 3055, 1435, 1024, 964,
758. Anal. Calcd for C26H24Br2O: C, 60.96; H, 4.72. Found: C, 60.87;
H, 4.63.
(300 MHz, CDCl3):
d
10.86 (2H, s), 8.15 (2H, d, J¼7.7 Hz), 7.61 (1H, t,
J¼7.7 Hz), 2.81 (2H, t, J¼7.3 Hz), 1.60e1.22 (20H, m), 0.88 (3H, t,
J¼6.9 Hz); 13C NMR (75 MHz, CDCl3):
d 191.6,142.7,138.7,133.7,129.3,
40.5, 31.9, 29.6 (2C), 29.54, 29.48, 29.4, 29.3, 29.0, 28.6, 22.7, 14.1.
Anal. Calcd for C20H30O2S$1/5H2O: C, 71.04; H, 9.06. Found: C, 71.28;
H, 8.98.
4.7. 2-Fluoro-1,3-bis(dibromomethyl)benzene (4f)
4.11. 1,3-Bis[2-(2-bromophenyl)ethenyl]-2-butylthiobenzene (5i)
A solution of 2-fluoro-1,3-dimethylbenzene (1.00 g, 8.05 mmol),
N-bromosuccinimide (5.70 g, 32.0 mmol), and benzoyl peroxide
(0.100 g, 0.412 mmol) in carbon tetrachloride (30 ml) was stirred
overnight at reflux temperature. The precipitates were removed by
filtration and the filtrate was absorbed into small amounts of silica
gel. The crude product was purified by column chromatography
(SiO2/hexane) to afford 4f (2.83 g, 6.44 mmol, 80%). Compound 4f:
A solution of 2-(butylthio)isophthalaldehyde (500.0 mg,
2.249 mmol), (2-bromobenzyl)triphenylphosphonium bromide12
(2.8680 g, 5.5992 mmol), and lithium hydroxide monohydrate
(282.0 mg, 6.721 mmol) in 2-propanol (30 ml) was refluxed for
12 h. After the solvent was removed under reduced temperature,
the residue was dissolved in dichloromethane and washed with
brine. The organic layer was dried over anhydrous MgSO4, filtered,
and the solvent was evaporated under reduced pressure. The crude
product was purified by column chromatography (SiO2/hex-
ane:ethyl acetate¼1:5) to afford 5i (1.0785 g, 2.0213 mmol, 90%).
Compound 5i: white solid; mp 120e140 ꢁC, 1H NMR (300 MHz,
white solid; mp 93e94 ꢁC, 1H NMR (300 MHz, CDCl3):
d 7.84 (2H, t,
JHH¼JHF¼7.7 Hz), 7.32 (1H, t, J¼7.7 Hz), 6.91 (2H, s); 13C NMR (75 Hz
CDCl3):
d
150.9 (d, JCF¼254.9 Hz), 131.8 (d, JCF¼2.1 Hz), 129.4 (d,
JCF¼12.3 Hz), 125.5 (d, JCF¼4.5 Hz), 30.7 (d, JCF¼6.6 Hz). Anal. Calcd
for C8H5Br4F: C, 21.85; H, 1.15. Found: C, 21.79; H, 1.25.
CDCl3):
d
8.00e6.73 (15H, m), 2.91e2.67 (2H, m), 1.63e1.45 (4H, m),
141.2, 137.3, 133.1,
0.93e0.85 (3H, m); 13C NMR (75 MHz, CDCl3):
d
4.8. 2-Chloro-1,3-bis(dibromomethyl)benzene (4g)
132.8,131.4,130.8,129.6,129.4,128.9,128.6,127.3,126.8,124.2, 35.6,
32.1, 22.1, 13.8. The complexity of the spectrum indicated a mixture
of the (E, E)-, (E, Z)-, and (Z, Z)-isomers. FABMS m/z 531 [MþH]þ
(28), 529 [MþH]þ (44), 527 [MþH]þ (24), 471 (15), 449 (20); IR
(cmꢀ1): 3053, 1466, 1434, 1024, 973, 758, 741. Anal. Calcd for
C26H24Br2S$1/2H2O: C, 58.11; H, 4.69. Found: C, 58.36; H, 4.44.
The same procedure for 4f was used, but using 2-chloro-1,3-
dimethylbenzene (1.00 g, 7.11 mmol), N-bromosuccinimide
(5.00 g, 28.1 mmol), and benzoyl peroxide (0.100 g, 0.412 mmol) in
carbon tetrachloride (30 ml). A 2.28 g of 4g was obtained
(5.00 mmol, 70%). Compound 4g: white solid; mp 127e128 ꢁC, 1H
NMR (300 MHz, CDCl3):
d
8.03 (2H, d, J¼7.9 Hz), 7.49 (1H, t, J¼7.9 Hz),
4.12. 1,3-Bis[2-(2-bromophenyl)ethenyl]-2-methylbenzene (5a)
7.12 (2H, s); 13C NMR (75 Hz CDCl3):
d
139.1, 132.2, 128.4 (2C), 35.9.
Anal. Calcd for C8H5Br4Cl: C, 21.06; H, 1.10. Found: C, 20.99; H, 1.26.
The same procedure for 5i was used, but using 2-methylisoph-
thalaldehyde15 (295.2 mg, 1.992 mmol) and corresponding other
reagents. A 855.3 mg of 5a was obtained (1.883 mmol, 94%). Com-
pound 5a: white solid; mp 85.0e86.0 ꢁC, 1H NMR (300 MHz, CDCl3):
4.9. 1,3-Bis[2-(2-bromophenyl)ethenyl]-2-chlorobenzene (5g)
To a solution of (2-bromobenzyl)triphenylphosphonium bro-
mide12 (7.00 g, 13.7 mmol) in THF (50 ml) was added potassium
tert-butoxide (1.60 g, 14.3 mmol) at 0 ꢁC and the reaction mixture
was stirred for 30 min. To the reaction mixture was added a solu-
tion of 2-chloroisophthalaldehyde14 (769.4 mg, 4.564 mmol) in THF
(50 ml), and the reaction mixture was stirred for 12 h at room
temperature. After the solvent was evaporated under reduced
pressure, the residue was dissolved in dichloromethane. The solu-
tion was washed with 3 M HCl, saturated aqueous Na2CO3 solution,
and water then the organic layer was dried over anhydrous MgSO4,
filtered, and the solvent was evaporated under reduced pressure.
The crude product was purified by column chromatography (SiO2/
hexane) to afford 5g (1.8412 g, 3.8793 mmol, 85%). Compound 5g:
white solid; mp 125e130 ꢁC, 1H NMR (300 MHz, CDCl3):
d
7.80e6.70 (15H, m), 2.50e2.10 (3H, m); 13C NMR (75 MHz, CDCl3):
d
137.5, 137.3, 137.2, 136.8, 136.7, 136.6, 134.3, 134.2, 133.1, 132.6,
131.4, 131.0, 130.9, 130.3, 130.1, 129.8, 129.3, 129.2, 128.8, 128.5,
127.6, 127.0, 126.8, 126.6, 126.4, 125.8, 125.4, 125.3, 124.2, 16.6, 16.2.
The complexity of the spectrum indicated a mixture of the (E, E)-,
(E, Z)-, and (Z, Z)-isomers. FABMS m/z 455 [MþH]þ (13); IR (cmꢀ1):
3060, 1466, 1435, 1022, 970, 757, 744. Anal. Calcd for C23H18Br2: C,
60.82; H, 3.99. Found: C, 60.73; H, 4.01.
4.13. 1,3-Bis[2-(2-bromophenyl)ethenyl]-2-trimethylsilyl-
benzene (5b)
The same procedure for 5i was used, but using 2-trimethylsilyl-
isophthalaldehyde (408.0 mg, 1.997 mmol) and corresponding
other reagents. A 835.1 mg of 5b was obtained (1.630 mmol, 82%).
Compound 5b: white solid; mp 70e90 ꢁC, 1H NMR (300 MHz,
d
7.70e6.66 (15H, m); 13C NMR (75 MHz, CDCl3):
d 137.1, 135.8,
132.6, 131.1, 130.9, 129.8, 126.9, 125.7, 124.0. The complexity of the
spectrum indicated a mixture of the (E, E)-, (E, Z)-, and (Z, Z)-iso-
mers. FABMS m/z 476 [MþH]þ (8), 474 [MþH]þ (10), 472 [MþH]þ
(5); IR (cmꢀ1): 3058, 1467, 1460, 1416, 1384, 1024, 949, 756, 740.
CDCl3):
CDCl3):
d
7.80e6.70 (15H, m), 0.45 (9H, m); 13C NMR (75 MHz,
144.8, 144.7, 144.1, 144.0, 137.3, 137.2, 137.1, 137.0, 135.3,
d
134.3, 134.2, 133.3, 132.7, 131.2, 129.6, 129.1, 129.0, 128.9, 128.8,