J Chem Crystallogr (2008) 38:205–209
207
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furnish the crude compound, which was purified by flash
column chromatography on silica gel (20 9 3 cm) using
EtOAc/hexanes (3:1) as eluent to give E amide (4) as a
white solid (0.378 g, 76%); Mp. 146 °C; 1H NMR (CDCl3)
d 3.33 (s, 3H), 3.82 (s, 6H), 5.50 (bs, 2H), 6.24 (d, 1H,
J = 3.2 Hz), 6.70–6.79 (m, 2H), 6.94 (d, 2H, J = 8.8 Hz),
7.21 (d, 2H, J = 8.8 Hz) and 8.12 (s, 1H); 13C NMR
(CDCl3) d 55.2, 55.4, 56.1, 111.9, 114.3, 114.8 (2C), 116.4,
124.5, 128.6, 131.3 (2C), 132.2, 133.9, 152.5, 153.0, 159.5
and 170.3; MS (ES+) m/z 314 (M + H); IR (CHCl3) 1,616,
1,673, 3,478, 3,522 cm-1; Anal. Calcd for C18H19NO4: C,
69.00; H, 6.11; N, 4.47. Found: C, 68.76; H, 6.10; N, 4.33.
Table 2 Selected bond lengths (A) and bond angles (°) for 1 and 2
1
2
C(3)–C(4)
1.468(8)
1.152(8)
1.438(10)
1.338(9)
1.466(8)
126.3(6)
177.2(8)
117.9(7)
115.7(6)
127.4(7)
123.7(6)
122.1(6)
122.3(8)
120.8(6)
1.440(8)
1.129(7)
1.427(9)
1.327(7)
1.513(7)
126.5(5)
178.8(7)
118.1(5)
115.4(5)
130.2(5)
120.6(5)
119.9(5)
120.7(5)
121.6(5)
C(1)–N
C(1)–C(2)
C(2)–C(3)
C(2)–C(10)
C(3)–C(2)–C(10)
N–C(1)–C(2)
C(3)–C(2)–C(1)
C(10)–C(2)–C(1)
C(2)–C(3)–C(4)
C(5)–C(4)–C(3)
C(11)–C(10)–C(2)
C(15)–C(10)–C(2)
C(9)–C(4)–C(3)
(E) 3-(2,5-Dimethoxyphenyl)-2-
(4-methoxyphenyl)acrylonitrile (2)
To a solution of E amide, 4 (0.252 g, 0.80 mmol) in pyr-
idine (7 mL) SOCl2 (3 mL) was added drop wise. The
resulting solution was stirred at room temperature for 12 h.
TLC analysis (1:1 EtOAc/hexanes) revealed that the reac-
tion was complete. The solvent and excess SOCl2 were
completely removed under reduced pressure. The residue
was dissolved in EtOAc (75 mL) and washed with 1 N HCl
(1 9 50 mL), water (1 9 50 mL) and brine (1 9 50 mL).
The organic layer was dried over Na2SO4. Drying agent
was filtered off and the solvent was removed under reduced
pressure to obtain the crude product. The crude compound
was purified by flash column chromatography over silica
gel (20 9 3 cm) using EtOAc/hexanes (1:5) as eluent to
furnish E cyanide, 2 as a yellow solid (0.187 g, 79%); Mp.
101 °C; 1H NMR (CDCl3) d 3.44 (s, 3H), 3.80 (s, 6H), 6.56
(s, 1H), 6.80–6.87 (m, 4H), 7.32 (d, 2H, J = 6.8 Hz) and
7.49 (s, 1H); 13C NMR (CDCl3) d 55.5, 55.6, 56.2, 112.2,
113.6, 114.3, 114.4 (3C), 117.5, 123.2, 125.2, 130.4 (2C),
138.2, 152.3, 152.9 and 160.2; MS (ES+) m/z 296
(M + H); IR (CHCl3) 1,607, 2,214 cm-1. Anal. Calcd for
C18H17NO3: C, 73.20; H, 5.80; N, 4.74. Found: C, 73.03;
H, 6.02; N, 4.77.
Table 3 Selected dihedral angles (°) for compounds 1 and 2
1
2
C(4)–C(9) ring
C(10)–C(15) ring
C(10)–C(15) ring
Alkenea
53.52
11.93
41.73
60.50
53.29
31.41
C(4)–C(9) ring
Alkenea
a
Alkene defined by plane through C2–C3–H3
(1.7 mL) was added dropwise. The reaction mixture was
stirred at room temperature for 4 h. The solvent was
completely removed under reduced pressure in nitrogen
atmosphere. The residue obtained was dried under high
vacuum to remove the traces of DMF. The resulting residue
was dissolved in CH2Cl2 (20 mL) and aqueous NH4OH
(50%, 10 mL) was added and the solution was stirred for
45 min at room temperature. TLC analysis (3:2 EtOAc/
hexanes) revealed that the reaction was complete. The
reaction mixture was then diluted with water (25 mL), and
the organic layer was separated. The aqueous layer was
extracted with dichloromethane (2 9 25 mL). The com-
bined organic layers were washed with brine (1 9 25 mL)
and dried over Na2SO4. The drying agent was filtered off,
and the filtrate was concentrated under reduced pressure to
X-ray Data Collection and Solution
For each compound, a suitable single crystal of the com-
pound was glued on a glass fiber with epoxy and aligned
Scheme 1
H3CO
H3CO
H3CO
H3CO
H3CO
H3CO
O
O
CN
1. SOCl2, DMF
2. NH4OH
1. SOCl2
DMF
OH
NH2
OCH3
OCH3
OCH3
2
3
4
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