Transition Met Chem
Fig. 1 Ligands used in this
work
Hcala: Yield, 49 %; mp 269–270 °C; 1H NMR
(d6-DMSO, ppm) d: 7.56 (d, 2H, J = 8.0 Hz, aromatic), 7.45
(d, 2H, J = 8.0 Hz, aromatic), 4.13 (m, 2H, CH2), 3.92 (s,
1H, CH), 1.48 (s, 3H, CH3). Anal. Calcd for C10H12ClNO2
(Mr = 213.66): C, 56.21 %; H, 5.66 %; N, 6.56 %. Found:
C, 56.14 %; H, 5.72 %; N. 6.48 %. FTIR(KBr pellet, cm-1):
3423 m, 1692 v, 1584 s, 1490 m, 1388 s, 1294 s, 1213 s,
1156 s, 1112 s, 1017 s, 827 s, 692 m, 537 s.
obtained with a Carlo Erba 1106 elemental analyzer. FTIR
spectra were recorded from KBr pellets in the range of
4000–400 cm-1 on a Mattson Alpha-Centauri spectrome-
ter. 1H NMR spectra were obtained at room temperature in
DMSO-d6 using a Bruker 400 MHz spectrometer.
Ligand preparations
Synthesis of [Ag2(Hshis)2]Á3H2O (1)
To a solution of the appropriate amino acid (10 mmol) in
water (10 mL) containing KOH (0.56 g, 10 mmol) was
added the appropriate aromatic aldehyde (10 mmol) in
EtOH (10 mL). The yellow solution was stirred for 30 min
at room temperature prior to cooling in an ice bath. The
intermediate Schiff base so obtained was reduced with
excess NaBH4 (0.46 g, 12 mmol). The yellow color slowly
discharged, and after 30 min the solution was acidified
with concentrated HCl to a pH of 4–6. The solvent was
then reduced to half and Et2O was added to precipitate the
product, which was filtered off, washed with ethanol fol-
lowed by diethyl ether, dried, and recrystallized from
water/ethanol (1:1).
A mixture of AgNO3 (0.034 g, 0.2 mmol) and H2shis
(0.052 g, 0.2 mmol) in water (6 mL) plus methanol
(14 mL) was stirred for 20 min at room temperature, and
then filtered. Colorless crystals of complex 1 were obtained
from the filtrate after standing at room temperature for
several days (72 % yield). Anal. Calcd for C26H34Ag2N6O9
(Mr = 790.32): C, 39.51 %; H, 4.33 %; N, 10.63 %.
Found: C, 39.68 %; H, 4.26 %; N, 10.77 %. FTIR(KBr
pellet, cm-1): 3450 m, 3329 s, 3180 m, 1833 s, 1710 s,
1644 s, 1345 m, 1230 s, 1175 m, 1070 w, 980 m, 805 m,
650 m.
H2shis: Yield, 51 %; mp 224–225 °C; 1H NMR
(d6-DMSO, ppm) d: 9.03 (s, 1H, imidazole), 7.49 (s, 1H,
imidazole), 7.39 (d, 1H, J = 12.0 Hz, aromatic), 7.19 (t,
1H, J = 16.0 Hz, aromatic), 6.97 (d, 1H, J = 8.0 Hz,
aromatic), 6.79 (t, 1H, J = 16.0 Hz, aromatic), 4.28 (t, 1H,
J = 12.0 Hz, CH), 4.17 (s, 2H, CH2), 3.49–3.34 (m, 2H,
CH2). Anal. Calcd for C13H15N3O3 (Mr = 261.28): C,
39.51 %; H, 4.34 %; N, 10.63 %. Found: C, 39.44 %; H,
4.42 %; N, 10.57 %. FTIR(KBr pellet, cm-1): 3430 m,
3106 m, 2903 m, 1605 v, 1513 m, 1464 s, 1415 s, 1377 s,
1282 s, 1190 m, 1090 m, 1039 m, 874 s, 826 s, 759 s,
658 m, 630 s.
Synthesis of Ag(Hcgly) (2)
A mixture of AgNO3 (0.034 g, 0.2 mmol), H2cgly
(0.043 g, 0.2 mmol), NaOH (0.004 g, 0.1 mmol), water
(10 mL), and methanol (10 mL) was stirred for several
minutes; then the precipitate was dissolved by dropwise
addition of an aqueous solution of NH3 (14 M). Colorless
block crystals were obtained by evaporation of the solution
for 10 days at room temperature (70 % yield). Anal. Calcd
for C9H9AgClNO3 (322.49): C, 33.52 %; H, 2.81 %; N,
4.34 %. Found: C, 33.51 %; H, 2.69 %; N, 4.29 %.
FTIR(KBr pellet, cm-1): 3370 m, 3289 s, 3145 s, 1878 m,
1690 s, 1536 m, 1370 w, 1310 m, 1156 m, 1080 s, 875 m,
745 m, 630 m.
H2cgly: Yield, 58 %; mp 221–222 °C; 1H NMR
(d6-DMSO, ppm) d: 7.31 (s, 1H, aromatic), 7.20 (d, 1H,
J = 8.0 Hz, aromatic), 6.85 (d, 1H, J = 8.0 Hz, aromatic),
3.92 (s, 2H, CH2), 3.20 (s, 2H, CH2). Anal. Calcd for C9
H10ClNO3 (Mr = 215.63): C, 50.13 %; H, 4.67 %; N,
6.50 %. Found: C, 50.22 %; H, 4.58 %; N, 6.42 %.
FTIR(KBr pellet, cm-1): 3445 w, 3202 m, 2746 m, 1628 s,
1582 v, 1500 s, 1456 s, 1412 s, 1377 s, 1253 s, 1124 s,
1060 m, 850 m, 820 s, 666 s, 548 s.
Synthesis of Ag(cala) (3)
A mixture of AgNO3 (0.034 g, 0.2 mmol), Hcala (0.042 g,
0.2 mmol), NaOH (0.004 g, 0.1 mmol), water (16 mL), and
methanol (4 mL) was stirred for several minutes; then the
precipitate was dissolved by dropwise addition of an aqueous
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