2
06
Transition Met Chem (2010) 35:205–211
were recorded on a Shimadzu 1700 UV–Vis spectropho-
tometer as Nujol mulls [17]. IR spectra were recorded in
dried. A methanol solution (10 mL) of ethylenediamine
(0.30 mL, 4 mmol) was added to a methanol suspension of
the above compound, and after shaking for a few minutes,
the resulting clear brown solution was filtered and kept for
crystallization. Brown crystals of 1 suitable for X-ray
analyses were obtained by slow evaporation of the solution
over a period of 10 days. Yield 62%. Mp 172 °C. Anal.
Found: C, 45.1; N, 21.0; H, 4.8; S, 12.0%. Calc. for
C H N NiO S C, 45.0; N, 21.0; H, 4.9; S, 12.0%. IR
-
the 4,000–400 cm region as KBr pellets on a Varian
1
1 13
Excalibur 3100-FT IR spectrophotometer. H and C NMR
spectra were recorded in DMSO-d on a JEOL AL 300 FT
6
NMR spectrometer using TMS as internal reference.
Synthesis of 5-phenyl-1,3,4-oxadiazole-2-thione (Hpot)
2
0
26
8
2 2
-
1
CS (1.5 mL, 25 mmol) was added dropwise to a solution
2
data (KBr, cm ); m(NH) 3,305, 3,245 m (en), m(C=N)
1,602; m (C–O–C) 1284w; m(N–N)1,075; m(C=S) 962;
of benzoic acid hydrazide (2.72 g, 20 mmol) in EtOH–
CHCl (25:75 v/v, 25 mL) plus Et N (0.8 g, 20 mmol).
m(Ni–N) 520w, l = 2.90 BM.
3
3
B
After stirring the reaction mixture for 3 h, the solution was
filtered and acidified with acetic acid (5 mL, 20% v/v). On
evaporation of the solvent, the resulting solid was washed
twice using an ethanol–water mixture (4:1), filtered and
Synthesis of [Ni(fot) (en) ] (2)
2
2
Freshly prepared K(H fchc) (0.480 g, 2 mmol) was dis-
2
crystallized from EtOH–CHCl mixture. Yield: 86%. Mp
3
solved in water (20 mL), and a solution of Ni(OAc) ꢀ4H O
2
2
1
2
13 °C [18]. H NMR (300 MHz, DMSO-d ): d = 13.56
(0.250 g, 1 mmol) in water (15 mL) was added. The
mixture was stirred for 15 min. The brown solid which
separated was filtered off, washed with methanol–water
mixture (50:50) and dried. A solution of ethylenediamine
(0.30 mL, 4 mmol) in methanol (10 mL) was added to a
methanol suspension of the above compound, and after
shaking for a few minutes, the resulting clear brown
solution was filtered and kept for crystallization. Brown
single crystals of 2 suitable for X-ray analysis were
obtained by slow evaporation of the solution over a period
of 10 days. Yield: 58%; Mp 260 °C. Anal. Found: C, 37.4;
H, 4.3; N, 21.8; S, 12.4%. Calc. for C H N NiO S : C,
6
1
s, 1H, NH), 8.55–7.25 (m, 5H, phenyl); C NMR
3
(
(
(
DMSO-d , TMS): d 131.48 (C1), 128.68 (C2, C6), 125.29
C3, C5), 121.73 (C4), 159.72 (C7), 176.74(C8). IR (KBr,
-
6
1
cm ): m(NH) 3,108, m(C=N) 1,610 s; m(C–O–C) 1,331 m;
m(N–N) 1,050 s; m(C=S) 1,145 m. Anal. Found: C, 53.8; H,
3
.4; N, 15.7%. Calc. for C H N OS (178.21): C, 53.9; H,
8 6 2
3
.4; N, 15.7.
0
Synthesis of potassium N -(furan-2-carbonyl) hydrazine
carbodithioate [K(H fchc)]
2
1
6
22
8
4 2
-
1
CS (1.5 mL, 25 mmol) was added dropwise to a solution
2
37.4; H, 4.3; N, 21.8; S, 12.5%. IR data (KBr, cm );
m(NH) 3,309(en), 3,261 m, m(C=N) 1,607; m(C–O–C)
1,324w; m(N–N) 1,086; m(C=S) 953; m(Ni–N) 523w,
lB = 2.84 BM.
of furan-2-carboxylic acid hydrazide (2.52 g, 20 mmol)
and potassium hydroxide (1.12 g, 20 mmol) in methanol
(
30 mL) with stirring. The mixture was stirred for 2 h. The
solid that separated was filtered off, washed with 10% (v/v)
mixture of EtOH–ether and dried in vacuo. Yield: 60%; Mp
1
Crystal structure determination and refinement
2
40 °C. H NMR (300 MHz, DMSO-d ): d = 11.60
6
1
s, 2H, NH), 8.8–7.3(m, 3H, furan); C NMR (DMSO-d6,
3
(
Data for the structures 1 and 2 were obtained at 296(2) and
150(2) K, on Bruker three-circle and Oxford Gemini
diffractometers, respectively, both equipped with SMART
6000 CCD software using graphite mono-chromated Mo
TMS): d 211.79 (C=S), 157.87 (C=O), 153.79 (C2), 146.91
-
1
(
C3), 144.87 (C4), 140.75(C5). IR (KBr, cm ): m(NH)
3
,218, 3,077, m(C=O) 1,655 s; m(N–N) 1,089 s; m(C=S)
˚
9
46 m. Anal. Found: C, 30.1; H, 2.1; N, 11.7, S, 26.7%.
Ka (k = 0.71073 A) radiation (Table 1). The structures
were solved by direct methods (SHELXS-08) and refined
Calc. for C H N O S K (240): C, 30.0; H, 2.1; N, 11.7, S,
6 5 2 2 2
2
against all data by full matrix least-square on F using
2
6.7%.
anisotropic displacement parameters for all non-hydrogen
atoms. In complex 2, the C4 and C5 atoms are disordered
over two positions with occupancy of 57:43%. All hydrogen
atoms were included in the refinement at geometrically ideal
position and refined with a riding model [19]. The MERCURY
and DIAMOND packages were used for molecular graphics
[20, 21]. Molecular structures were generated by use of the
ORTEP-3 for windows program [22].
Synthesis of [Ni(pot) (en) ] (1)
2
2
Hpot (0.358 g, 2 mmol) and Ni(OAc) ꢀ4H O (0.250 g,
2
2
1
mmol) were dissolved separately in methanol (20 mL),
then the solutions were mixed together and stirred for
–10 min. The brown solid which separated was filtered
off, washed with methanol–water mixture (50:50) and
5
1
23