108
G. Nirmala et al. / Polyhedron 30 (2011) 106–113
0.008 mol). The crude product thus obtained was recrystallized
from acetonitrile to afford L2 as a yellowish white solid.
1635
nm (
m
e
(C@O). Conductance (Km/S cm2 molꢀ1) in CH3CN: 18. kmax
, Mꢀ1 cmꢀ1) in DMF: 476 (144), 377 (16 342), 310 (23 620).
,
Yield: 2.1 g (75 %). M.p: 294 °C. Anal. Calc. C26H28O6N4Br2: C,
47.87; H, 4.32; N, 8.58. Found: C, 47.80; H, 4.30; N, 8.50%. Selected
gll 2.47, g? 2.16, All 162. leff: 1.70.
IR (KBr) (
NMR (d ppm in CDCl3): 1.9–2.26 (m, 12H,
4H, CH2–CH2–C@O), 4.4–4.8 (m, 4H, benzylic CH2), 7.26 (m, 4H,
m
/cmꢀ1): 3385
m(OH), 3294
m
(NH), 1668, 1642
m
(C@O). 1H
2.4.2. [CuL2]
a-CH2), 3.38–3.43 (m,
Brown solid. Yield: 0.76 g (70%). Anal. Calc. for [C26H28N4O6Br2-
Cu]: C, 43.74; H, 3.66; N, 7.84; Cu, 8.89. Found: C, 43.67; H, 3.60; N,
7.79, Cu, 8.78%. Selected IR (KBr) (
1636
(C@O). FAB Mass [M]+: 712. Conductance (Km/S cm2 molꢀ1
in CH3CN: 14. kmax, nm (
, Mꢀ1 cmꢀ1) in DMF: 568 (169), 395
m m(O–H), 1658,
/cmꢀ1): 3390
Ar–H), 9.77 (s, 2H, Ar–CHO), 9.86 (s, 2H, H2C–NH–). kmax, nm (e,
Mꢀ1 cmꢀ1) in DMF: 265 (22 380).
m
)
e
2.3.3. Synthesis of N,N-bis[1,8-dibenzoyl]-5,12-dioxo-1,4,8,11-tetra-
azacycloteradecane (L3)
(15 400), 312 (33 600). gll 2.31, g? 2.09, All 160. leff: 1.73.
Ligand L3 was prepared by a method similar to that described
for L1 by using two equivalent of benzoyl chloride (1 mL,
0.009 mol). The crude product thus obtained was recrystallized
from DMF to afford L3 as a white solid.
2.4.3. [CuL3]
Brown solid. Yield: 0.89 g (80%). Anal. Calc. for [C24H26N4O4Cu]:
C, 57.87; H, 5.26; N, 11.24, Cu, 12.75. Found: C, 57.80; H, 5.21; N,
11.19, Cu, 12.69%. Selected IR (KBr) (
FAB Mass [M]+: 497. Conductance (Km/S cm2 molꢀ1) in CH3CN:
12. kmax, nm (
, Mꢀ1 cmꢀ1) in DMF: 490 (145), 380 (12 400), 311
m m(C@O).
/cmꢀ1): 1659, 1624
Yield: 1.24 g (75 %). M.p: 300 °C. Anal. Calc. for [C24H28O4N4]: C,
66.03; H, 6.47; N, 12.83. Found: C, 66.00; H, 6.39; N, 12.76%; Se-
e
lected IR (KBr) (
NMR (d ppm in CDCl3): 1.17 (s, 6H, CH3), 1.9–2.26 (m, 12H,
CH2), 3.35–3.43 (m, 4H, CH2–CH2–C@O), 7.26 (m, 4H, Ar–H), 9.86
(s, 2H, CH2–NH). kmax, nm (
, Mꢀ1 cmꢀ1) in DMF: 267 (22 410).
m m(N–H), 1672, 1634 m
/cmꢀ1): 3295 (C@O). 1H
(24 650). gll 2.30 g? 2.07, All 171. leff: 1.71.
a
-
2.4.4. [CuL4]
e
Brown solid. Yield: 0.84 g (75%). Anal. Calc. for [C24H24N6O8Cu]:
C, 49.01; H, 4.11; N, 14.29, Cu, 10.81. Found: C, 48.97; H, 4.05; N,
2.3.4. Synthesis of N,N-bis[1,8-(2-nitrobenzoyl)]-5,12-dioxo-1,4,8,11-
tetraazacyclotetradecane (L4)
14.19, Cu, 10.75%. Selected IR (KBr) (
1550 asym(NO2), 1344
sym(NO2). Conductance (Km/S cm2 molꢀ1
in CH3CN: 18. kmax, nm (
, Mꢀ1 cmꢀ1) in DMF: 538 (162), 392
m m(C@O),
/cmꢀ1): 1663, 1639
m
m
)
Ligand L4 was prepared by a method similar to that described
for L1 by using two equivalent of o-nitrobenzoyl chloride (1.2 mL,
0.009 mol). The crude product thus obtained was recrystallized
from DMF to afford L4 as a yellowish white solid.
e
(14 230), 304 (30 220). gll 2.29, g? 2.09, All 170. leff: 1.72.
2.4.5. [CuL5]
Yield: 1.24 g (65 %) M.p: 280 °C. Anal. Calc. for [C24H26O8N6]: C,
54.74; H, 4.98; N, 15.96. Found: C, 54.63; H, 4.89; N, 15.87%; Se-
Brown solid. Yield: 0.84 g (75%). Anal. Calc. for [C24H24N6O8Cu]:
C, 49.01; H, 4.11; N, 14.29, Cu, 10.20. Found: C, 48.97; H, 4.05; N,
lected IR (KBr) (
asym(NO2), 1350
6H, CH3), 1.9–2.26 (m, 12H,
m
/cmꢀ1): 3290
m
m
(N–H), 1665, 1645,
sym(NO2). 1H NMR (d ppm in CDCl3): 1.17 (s,
-CH2), 3.35–3.43 (m, 4H, CH2–CH2–
m(C@O), 1558
14.19, Cu, 10.15%. Selected IR (KBr) (
1542 asym(NO2), 1341
sym(NO2). Conductance (Km/S cm2 molꢀ1
in CH3CN: 18. kmax, nm (
, Mꢀ1 cmꢀ1) in DMF: 542 (160), 387
m m(C@O),
/cmꢀ1): 1660, 1639
m
m
m
)
a
e
C@O), 7.26 (m, 4H, Ar–H), 9.86 (s, 2H, CH2–NH). kmax, nm (e,
(14 200), 309 (30 100). gll 2.31, g? 2.10, All 162. leff: 1.71.
Mꢀ1 cmꢀ1) in DMF: 280 (22 470).
2.4.6. [NiL1]
2.3.5. Synthesis of N,N-bis[1,8-(4-nitrobenzoyl)]-5,12-dioxo-1,4,8,11-
tetraazacyclotetradecane (L5)
Yellowish green solid. Yield: 0.830 g (75%). Anal. Calc. for
[C28H32N4O6Ni]: C, 58.03; H, 5.56; N, 9.67, Ni, 10.13. Found: C,
Ligand L4 was prepared by a method similar to that described
for L1 by using two equivalent of p-nitrobenzoyl chloride (1.67 g,
0.009 mol). The crude product thus obtained was recrystallized
from DMF to afford L5 as a yellowish white solid.
58.00; H, 5.46; N, 9.57, Ni, 10.03%. Selected IR (KBr) (
3398 (O–H), 1658, 1634
(C@O). Conductance (Km/S cm2 molꢀ1
, Mꢀ1 cmꢀ1) in DMF: 480 (160), 378
m
/cmꢀ1):
m
m
e
)
in CH3CN: 16. kmax, nm (
(14 765), 314 (26 600).
Yield: 1.24 g (65 %). M.p: 280 °C. Anal. Calc. for [C24H26O8N6]: C,
54.74; H, 4.98; N, 15.96. Found: C, 54.63; H, 4.89; N, 15.87%; Se-
2.4.7. [NiL2]
lected IR (KBr) (
asym(NO2), 1348
6H, CH3), 1.9–2.26 (m, 12H,
m
/cmꢀ1): 3275
m
m
(N–H), 1660, 1642
sym(NO2). 1H NMR (d ppm in CDCl3): 1.17 (s,
-CH2), 3.35–3.43 (m, 4H, CH2–CH2–
m(C@O), 1553
Yellowish green solid. Yield: 0.86 g (80%). Anal. Calc. for
m
[C26H26N4O6Br2Ni]: C, 44.04; H, 3.69; N, 7.90, Ni, 8.27. Found: C,
a
44.00; H, 3.62; N, 7.85; Ni, 8.20%. Selected IR (KBr) (m
/cmꢀ1):
C@O), 7.26 (m, 4H, Ar–H), 9.86 (s, 2H, CH2–NH). kmax, nm (e,
Mꢀ1 cmꢀ1) in DMF: 275 (22 450).
3410
m
(O–H), 1650, 1630
m
(C@O). FAB Mass [MꢀL]: 708. Conduc-
tance (Km/S cm2 molꢀ1) in CH3CN: 13. kmax, nm ( , Mꢀ1 cmꢀ1) in
e
DMF: 490 (162), 391 (16 620), 309 (30 280).
2.4. Synthesis of macrocyclic mononuclear copper(II) and nickel(II)
complexes
2.4.8. [NiL3]
Yellowish green solid. Yield: 0.73 g (65%). Anal. Calc. for
The copper(II) and nickel(II) complexes were prepared by
refluxing the respective metal perchlorate (1 mmol) in methanol
(50 mL) with appropriate ligands (1 mmol) in DMF (50 mL). The
resulting solution was refluxed for 8 h. Then the solution was fil-
tered whilst hot and allowed to stand at room temperature. After
the evaporation of solvent, the compound was recrystallised from
acetonitrile to get the pure complexes.
[C24H26N4O4Ni]: C, 58.44; H, 5.32; N, 11.35, Ni, 10.85. Found: C,
58.39; H, 5.27; N, 11.30, Ni, 10.78%. Selected IR (KBr) (
1659, 1628
(C@O). Conductance (Km/S cm2 molꢀ1) in CH3CN:
, Mꢀ1 cmꢀ1) in DMF: 561 (172), 370 (13 480), 312
m
/cmꢀ1):
m
15. kmax, nm (
e
(26 600).
2.4.9. [NiL4]
2.4.1. [CuL1]
Yellowish green solid. Yield: 0.80 g (70%). Anal. Calc. for
Brown solid. Yield: 0.89 g (80 %). Anal. Calc. for [C28H32N4O6Cu]:
C, 57.55; H, 5.52; N, 9.59, Cu, 10.87. Found: C, 57.50; H, 5.44; N,
[C24H24N6O8Ni]: C, 49.42; H, 4.15; N, 14.41, Ni, 10.06. Found: C,
49.38; H, 4.05; N, 14.35; Ni, 10.00%. Selected IR (KBr) (
1652, 1634 (C@O), 1554 asym(NO2), 1340 sym(NO2). Conductance
m
/cmꢀ1):
9.50, Cu, 10.80%. Selected IR (KBr) (
m
/cmꢀ1): 3420
m(O–H), 1655,
m
m
m