water was added until precipitation occurred. After filtering the precipitates, they were sequentially washed with
ice-cooled water and ethanol and then dried in a vacuum.
-
1
3
,3′-Benzylidene-bis-(4-hydroxycoumarin) (1): m.p. 208-209 °C. IR (KBr pellet cm ): 3446 (OH), 1652
-
1
1
(
C=O), 1615 (C-O), 1572 (C=C) cm . H NMR (CDCl
3
, δ, ppm): 11.528 (s, 1H, OH), 11.299 (s, 1H, OH),
+
7
.994-8.080 (q, 2H), 7.606-7.649 (m, 2H), 7.215-7.421 (m, 9H), 6.104 (s, 1H, CH). HRMS (ESI ): m/z: calcd for
+
C
25
H
16
O
6
: 435.0839 [M+Na ]; found: 435.0899.
-
1
3
,3′-(2-Nitrobenzylidene)-bis-(4-hydroxycoumarin) (2): m.p. 218-219 °C. IR (KBr pellet cm ): 3446
-
1 1
(
OH), 1652 (C=O), 1615 (C-O), 1520 (C=C) cm . H NMR (CDCl
3
, δ, ppm): 11.550 (s, 1H, OH), 11.219 (s, 1H,
OH), 7.978-8.073 (m, 2H), 7.612-7.658 (m, 3H), 7.540-7.582 (m, 1H), 7.386-7.464 (m, 6H), 6.628 (s, 1H, CH).
+
+
HRMS (ESI ): m/z: calcd for C25
8
H15NO : 480.0690 [M+Na ]; found: 480.0611.
-
1
3
,3′-(3-Nitrobenzylidene)-bis-(4-hydroxycoumarin) (NBH): m.p. 220-221 °C. IR (KBr pellet cm ): 3446
-
1 1
(
3
OH), 1652 (C=O), 1615 (C-O), 1555 (C=C) cm . H NMR (CDCl , δ, ppm): 11.579 (s, 1H, OH), 11.384 (s, 1H,
OH), 8.137-8.162 (m, 1H), 8.070-8.104 (t, 2H), 7.990-8.008 (d, 1H), 7.651-7.690 (t, 2H), 7.568-7.591 (m, 1H),
+
7
.496-7.536 (t, 1H), 7.385-7.453 (m, 4H), 6.129 (s, 1H, CH). HRMS (ESI ): m/z: calcd for C25
H
15NO
8
: 480.0690
+
[
M+Na ]; found: 480.0689.
-
1
3
,3′-(2-Chloro-5-nitrobenzylidene)-bis-(4-hydroxycoumarin) (CBH): m.p. 150-151 °C. IR (KBr pellet cm ):
-
1 1
3
1
4
489 (OH), 1684 (C=O), 1623 (C-O), 1520 (C=C) cm . H NMR (CDCl
3
, δ, ppm): 11.752 (s, 1H, OH), 11.006 (s,
H, OH), 8.359-8.365 (t, 1H), 8.064-8.144 (m, 3H), 7.640-7.683 (m, 2H), 7.533-7.555 (d, 1H), 7.402-7.438 (t,
+
+
H), 6.192 (s, 1H, CH). HRMS (ESI ): m/z: calcd for C25
8
H14ClNO : 514.0300 [M+Na ]; found: 514.0321.
3
,3′-(3-Nitro-4-hydroxybenzylidene)-bis-(4-hydroxycoumarin) (NHH): m.p. 238-239 °C. IR (KBr pellet
-
1
-1 1
cm ): 3251 (OH), 1655 (C=O), 1582 (C-O), 1536 (C=C) cm . H NMR (CDCl
3
, δ, ppm): 11.593 (s, 1H, OH),
1
1
4
1.396 (s, 1H, OH), 10.545-10.558 (d, 1H), 7.944-8.108 (m, 3H), 7.686 (s, 2H), 7.402-7.466 (m, 4H), 7.287 (s,
+
+
H), 7.142-7.176 (q, 1H), 6.046 (s, 1H, CH). HRMS (ESI ): m/z: calcd for C25
H
9
15NO : 496.0639 [M+Na ]; found:
96.0632.
2
.3 Crystal structure determination
For X-ray diffraction experiments, single crystals of compound 4 were both grown from methanol. The X-ray
diffraction data were collected on a Bruker SMART APEX II CCD diffractometer equipped with a graphite
monochromated Mo Kα radiation (λ = 0.71073 Å) by using the ω-2θ scan technique at room temperature. The
structure was solved by direct methods using SHELXS-97 and refined using the full-matrix least squares method
2
[14]
on F with anisotropic thermal parameters for all non-hydrogen atoms by using SHELXL-97 . Hydrogen atoms
were generated geometrically. The crystal data and details concerning data collection and structure refinement are
given in Table 1. Molecular illustrations were prepared using the XP package. Parameters in CIF format are
available as Electronic Supplementary Publication from Cambridge Crystallographic Data Centre.
Table 1 Crystal data, data collection and structure refinement of compound 4
Formula
Mr
25 8
C H14ClNO
491.0408
293(2)
Temperature / K
Crystal system
Space group
a / Å
Triclinic
Pī
9.7912(9)
11.2742(8)
12.0934(13)
64.872(9)
79.063(9)
84.199(7)
b / Å
c / Å
α / °
β / °
γ / °