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18.41, 21.04, 26.40, 28.70, 38.93, 41.48, 46.78, 47.17,
117.78, 119.95, 133.37, 137.49, 141.93, 153.27, 155.55,
159.88; anal. calcd for C31H35N3·H2O: C, 79.62; H,
7.97; N, 8.99. Found: C, 77.95; H, 7.93; N, 8.80%.
Positive ion FAB mass spectrum m/z: 450 (MH+).
Cu(L2)Cl2: The above procedure was followed using L2
to give Cu(L2)Cl2 (0.20 g, 85%). IR (KBr): 2960.6 vs,
2873.7 m, 1582.3 s, 1479.9 s; visible spectrum (CH2Cl2),
umax (m): 302 nm (31000), 333 nm (25000), 860 nm (150);
anal. calcd for C31H35N3CuCl2·H2O: C, 61.84; H, 6.19;
N, 6.98. Found: C, 61.80; H, 6.16; N, 7.24%; positive
ion FAB mass spectrum m/z: 547 (M+−Cl).
Terpyridine L4: The above procedure was modified
using a,b-unsaturated ketone 8 and ethanol as solvent.
Workup and purification by column chromatography
with petroleum ether–acetone–Et2O (90:1:1) gave 0.066
g (10%) of terpyridines L4a–c. L4a (0.024 g); L4b (0.010
g); L4c (0.026 g); mixture of L4a, L4b and L4c (0.006 g).
Cu(L3a)Cl2: The above procedure was followed using
L3a to give Cu(L3a)Cl2 (0.19 g, 80%); IR (KBr): 2926.2
vs, 1573.8 m, 1427.1 m; visible spectrum (CH2Cl2), umax
(m): 347 nm (17000), 474 nm (880), 887 nm (110); anal.
calcd for C31H35N3CuCl2·H2O: C, 57.44; H, 5.57; N,
6.28. Found: C, 55.60; H, 5.72; N, 6.23%; positive ion
FAB mass spectrum m/z: 547 (M+−Cl).
Terpyridine L4a: Mp 155–158°C [h]2D5=−58.8 (c=0.50,
CH2Cl2); IR (KBr) 2959.4 vs, 2929.9 vs, 2870.8 m,
1
1557.6 vs, 1428.6 vs; H NMR (300 MHz, CDCl3): l
0.77 (d, J=6.9 Hz, 6H), 1.12 (d, J=6.9 Hz, 6H), 1.30
(d, J=7.2 Hz, 6H), 1.73–1.96 (m, 8H), 2.90–3.15 (m,
6H), 7.57 (d, J=8.0 Hz, 2H), 7.87–7.92 (t, J=8.0 Hz,
1H), 8.36 (d, J=8.0 Hz, 2H), 8.45 (d, J=8.0 Hz, 2H).
13C NMR (CDCl3): l 17.35, 18.41, 20.90, 22.96, 28.57,
29.92, 32.48, 46.29, 118.00, 120.44, 137.06, 137.48,
138.31, 153.01, 155.63, 158.43; anal. calcd for
C31H39N3·H2O: C, 78.94; H, 8.76; N, 8.91. Found: C,
79.09; H, 8.56; N, 8.70%; positive ion FAB mass spec-
trum m/z: 454 (MH+).
3.9. General procedure for preparation of rhodium(III)–
terpyridine complexes Rh(L)Cl3
A mixture of terpyridine L (0.2 mmol) and rhodiu-
m(III) chloride (0.2 mmol) in ethanol (10 mL) was
stirred under reflux overnight to ensure complete com-
plexation. The solution was cooled and the solvent was
removed. The product was recrystallized from
dichloromethane/Et2O to yield a yellow solid, which
was filtered and washed with diethyl ether. The com-
plex was characterized by IR, 1H NMR, UV spec-
troscopy, CHN analysis and MS analysis.
Terpyridine L4c: Mp 124–125°C; [h]2D5=−49.0 (c=0.53,
CH2Cl2); IR (KBr) 2950.0 vs, 2870.8 m, 1561.3 m,
1432.3 vs; 1H NMR (300 MHz, CDCl3): l 0.71 (d,
J=6.6 Hz, 3H), 0.77 (d, J=6.6 Hz, 3H), 1.10 (d, J=8.8
Hz, 3H), 1.12 (d, J=8.8 Hz, 3H), 1.30 (d, J=6.9 Hz,
3H), 1.33 (d, J=6.9 Hz, 3H), 1.65–2.20 (m, 8H), 2.89–
3.19 (m, 6H), 7.57 (d, J=8.0 Hz, 1H), 7.70 (d, J=8.0
Hz, 1H), 7.88–7.93 (t, J=8.0 Hz, 1H), 8.35 (d, J=8.0
Hz, 2H), 8.45 (d, J=8.0 Hz, 2H); 13C NMR (CDCl3): l
17.17, 17.38, 18.45, 20.81, 20.92, 21.48, 21.59, 22.97,
28.54, 29.71, 29.99, 30.51, 31.18, 32.50, 32.89; anal.
calcd for C31H39N3·H2O: C, 78.94; H, 8.76; N, 8.91.
Found: C, 80.96; H, 8.76; N, 9.27%; positive ion FAB
mass spectrum m/z: 454 (MH+).
Rh(L1)Cl3: The above procedure was followed using L1
to give Rh(L1)Cl3 (0.09 g, 71%). IR (KBr): 3058.0 s,
2920.8 vs, 2866.9 vs, 1595.6 m, 1580.1 m; 1H NMR (300
MHz, CDCl3): l 0.96 (s, 6H), 1.11 (d, J=10.2 Hz, 2H),
1.60 (s, 6H), 2.28–2.35 (m, 2H), 2.75–2.83 (m, 2H),
3.04–3.11 (m, 4H), 5.53–5.56 (m, 2H), 7.66 (d, J=7.5
Hz, 2H), 7.85 (d, J=7.5 Hz, 2H), 7.97 (d, J=7.5 Hz,
2H), 8.10 (t, J=7.5 Hz, 1H); visible spectrum (CH2Cl2),
umax (m): 354 nm (21000), 312 nm (20500), 428 nm (540);
anal. calcd for C29H31N3RhCl3: C, 55.20; H, 4.95; N,
6.66. Found: C, 54.67; H, 4.74; N, 6.12%; positive ion
FAB mass spectrum m/z: 594 (M+−Cl).
3.8. General procedure for preparation of copper(II)–
terpyridine complexes [Cu(L)Cl2]
Rh(L2)Cl3: The above procedure was followed using L2
to give Rh(L2)Cl3 (0.10 g, 76%). IR (KBr): 3058.9 s,
1
2961.8 vs, 2873.2 s, 1601.6 m, 1578.6 m; H NMR (300
A
solution of terpyridine
L
(0.4 mmol) in
MHz, CD2Cl2): l 0.39 (s, 6H), 0.97 (s, 6H), 1.32–1.41
(m, 2H), 1.78 (s, 6H), 1.97–2.06 (m, 2H), 2.17–2.28 (m,
2H), 2.55–2.64 (m, 2H), 2.89 (d, J=3.9 Hz, 2H), 7.66
(d, J=7.5 Hz, 2H), 7.81 (d, J=7.5 Hz, 2H), 7.95 (d,
J=7.8 Hz, 2H), 8.19 (t, J=7.8 Hz, 2H); visible spec-
trum (CH2Cl2), umax (m): 300 nm (22500), 335 nm
(20500), 348 nm (22000), 433 nm (490); anal. calcd for
C31H35N3RhCl3·H2O: C, 54.99; H, 5.51; N, 6.21.
Found: C, 55.30; H, 5.17; N, 5.83%; positive ion FAB
mass spectrum m/z: 622 (M+−Cl).
dichloromethane (5 mL) was added dropwise to a
solution of CuCl2·2H2O (0.068 g, 0.4 mmol) in ethanol
(5 mL). The solution was stirred under reflux overnight
to ensure complete complexation. The solution was
then cooled and diethyl ether was added until a precip-
itate was formed. The product was filtered and washed
with diethyl ether. The complex was characterized by
IR, UV, CHN and MS analyses.
Cu(L1)Cl2: The above procedure was followed using L1
to give Cu(L1)Cl2 (0.18 g, 83%). IR (KBr): 2964.3 s,
2914.7 m, 1593.4 m, 1454.2 s; visible spectrum
(CH2Cl2), umax (m): 339 nm (21000), 353 nm (20000), 901
nm (210); anal. calcd for C29H31N3CuCl2·CH2Cl2: C,
56.20; H, 5.19; N, 6.55. Found: C, 56.53; H, 5.06; N,
6.74%; positive ion FAB mass spectrum m/z: 519 (M+−
Cl).
Rh(L3a)Cl3: The above procedure was followed using
L3a to give Rh(L3a)Cl3 (0.12 g, 91%); IR (KBr): 3071.7
1
s, 2924.5 vs, 2866.9 vs, 1602.4 m, 1581.8 m; H NMR
(300 MHz, CDCl3): l 0.85 (s, 6H), 1.42 (d, 2H), 1.44 (s,
6H), 1.61 (d, J=6.6 Hz, 6H), 2.23–2.28 (m, 2H), 2.48–
2.55 (m, 2H), 2.84–2.88 (m, 2H), 5.62–5.70 (m, 2H),
7.46 (d, J=7.8 Hz, 2H), 7.83 (d, J=7.8 Hz, 2H), 8.02