RSC Advances
Journal Name
DOI: 10.1039/C5RA061 A
ART12ICLE
centre for cell Science (NCCS), Pune, India. All other Nꢀ(2,4,6ꢀTrimethylphenyl)pyridineꢀ2ꢀthiocarboxamide(L3):
chemicals and reagents used for the biological studies were of Yellowꢀbrown; Yield:74%; M.p.117ꢀ119°C. C H N S
15 16 2
(
7
256.37): calcd. C 70.28, H 6.29, N 10.93, S 12.51; found C
0.21, H 6.41, N 10.72, S 12.48. H NMR (400 MHz, CDCl ):
3
high quality in biological grade. Elemental analyses were
performed on a vario EL III CHNS elemental analyser. Melting
points were performed with an electrical instrument and are
uncorrected. Infrared spectra were recorded in KBr pellets with
1
δ = 2.22 (s, 6 H, 2ꢀ and 6ꢀPhCH ), 2.33 (s, 3H, 4ꢀPhCH ), 6.99
(
1
H, 4ꢀPyH), 8.58 (ddd, J = 4.8, J = 1.8, J = 0.9 Hz, 1 H,
6
PyH), 11.29 (br. s, 1 H, CSNH) ppm.IR (KBr): ν = 3274, 855
cmꢀ1.
3
3
3
3
4
s, 2 H, 3ꢀ and 5ꢀPhH), 7.50 (ddd, J = 7.7, J =4.8, J
=
3,5
4,5
3
4,5
5,6
3
4
1
13
.2 Hz, 1 H, 5ꢀPyH), 7.89 (dt, J = J =7.7, J = 1.8 Hz, 1
a JASCO 200 plus spectrometer. The HꢀNMR and CꢀNMR
were recorded on a high resolution Bruker 400 MHz instrument
and the chemical shifts given in ppm are referenced to the
deuterated solvents. Electronic spectroscopy was recorded with
a Cary 300 Bio Varian spectrophotometer using cuvettes of 1
cm path length. Emission intensity measurements were carried
out using a Jasco FPꢀ6500 spectrofluorimeter. The circular
dichromism spectra were recorded using a JASCO Jꢀ810
spectropolarimeter equipped with a peltier Temperature control
device at room temperature with a quartz cell of 1cm path
3,4
4
4,6
3
5
5,6
4,6
3,6
3
4
5
ꢀPyH), 8.80 (ddd, J = 7.7, J = 1.2, J = 0.9 Hz, 1 H, 3ꢀ
3,4 3,5 3,6
Nꢀ(2ꢀChlorophenyl)pyridineꢀ2ꢀthiocarboxamide(L4):
Orange; Yield: 74%; M.p. 93ꢀ95°C. C H ClN S (248.75):
calcd. C 57.94, H 3.64, N 11.26, S 12.86; found C 57.87, H
3
(
4
1
8.45 (ddd, J =4.8, J = 1.8, J =0.9 Hz, 1 H, 6ꢀPyH), 8.73
5,6 4,6 3,6
(
(
12
9
2
1
.59, N 11.22, S 12.77. H NMR (400 MHz, CDCl ): δ = 7.26
3
3
3
3
d, J=8.4 Hz, 2 H, 3ꢀ and 5ꢀPhH), 7.46 (ddd, J = 7.7, J
=
=
length. Each sample solution was the average of
3
4,5
3
5,6
4
3
4
.8, J = 1.2 Hz, 1 H, 5ꢀPyH), 7.84 (dt, J = J =7.7, J
3,5 3,4 4,5
.8 Hz, 1 H, 4ꢀPyH), 7.93 (d, J =8.4 Hz, 2 H, 2ꢀ and 6ꢀPhH),
accumulations using a scan speed of 500 nm/ min at 1s
response time. The viscosity measurements were carried out on
4,6
3
3
4
5
°
a Schott Gerate AVS 310 viscometer at 30.0±0.1 C in a
3
4
5
ddd, J =7.7, J = 1.2, J = 0.9 Hz, 1 H, 3ꢀPyH), 10.38
3,4 3,5 3,6
thermostatic waterbath.
ꢀ
1
br. s, 1 H, CSNH) ppm.IR (KBr):
ν = 3214, 840 cm .
Preparation of thiocarboxamide ligands
The bidentate thiocarboxamides ligands (L1ꢀL4) were prepared
by reported procedure. A mixture of substituted aniline (0.10
mol), sulfur (0.30 mol) and sodium sulfide nonahydrate (2 mol
Synthesis of new square plannar nickel(II) thiocarboxamide
complexes
5
4
All the reactions were carried out under unhydrous conditions
and the new nickel(II) complexes were prepared by the
following procedure : To a solution of thiocarboxamide
ligands (2mmol) (L1ꢀL4) was added in ethanol under constant
%
) in 2ꢀmethylpyridine (60 mL) was refluxed for 48 h. After
cooling and removal of all volatiles in vacuum, the dark solid
residue was taken up in dichloromethane (200 mL), and the
mixture was filtered through a column of silica gel. The filtrate
was evaporated under reduced pressure, and the resulting solid
was dried in vacuum. Recrystallisation from ethanol gave yield
5
5
3
stirring. Solid Ni(CH COO)2
2
⋅4H O (1 mmol) was added and
the solution was heated to refluxed for 5h. A yellow colored
mononuclear nickel complex [Ni(L) ] precipitated. The solid
(
74ꢀ79%) of analytically pure thiocarboxamide ligands as a
2
was separated by the filtration and washed with ethanol and
dried under vacuum. (Scheme: 1)
yellow to orange crystalline solid.
Nꢀ(2ꢀMethylphenyl)pyridineꢀ2ꢀthiocarboxamide(L1):
Yellow; Yield: 75%; M.p. 99ꢀ101°C. C H N S (228.31):
1
3
12
2
[
Ni (L1) ] (1)
2
calcd. C 68.39, H 5.30, N 12.27, S 14.04; found C 68.10, H
1
Yield: 79.5%. M.P. 246
°C Color: Yellow. Anal. Calc. for
5
.58, N 12.40, S 13.01. H NMR (400 MHz, CDCl ): δ = 2.1 (s,
3
3
C H N S Ni: C; 60.84, H; 4.32, N; 10.91, S; 12.46. Found: C;
3
H, PhCH ), 7.26 (d, J=8.4 Hz, 2 H, 3ꢀ and 5ꢀPhH), 7.46 (ddd,
26 22
4 2
3
3
ꢀ
1
3
4
3
60.70, H; 4.39, N; 10.80, S; 12.31. IR (KBr, cm ) γ= 1620,
1202. UVꢀVis in CHCl3: ꢉmax/nm (εmax/dm mol cm )
241(70,280), 270(72,730), 344(5279), 466(1393). H NMR
J
= 7.7, J = 4.8, J = 1.2 Hz, 1 H, 5ꢀPyH), 7.87 (dt, J
5,6 3,5 3,4
4
3
,5
3
ꢀ1
ꢀ1
4
3
=
2
J4,5 =7.7, J = 1.8 Hz, 1 H, 4ꢀPyH), 7.93 (d, J =8.4 Hz, 2 H,
4,6
1
3
4
5
ꢀ and 6ꢀPhH), 8.54 (ddd, J = 4.8, J =1.8, J = 0.9 Hz, 1
5,6 4,6 3,6
3
4
5
(400 MHz, CDCl ): 2.2 (s, CH , 6H), 7.01ꢀ7.14 (m, 8 H, Arꢀ
H, 6ꢀPyH), 8.80 (ddd, J =7.7, J = 1.2, J =0.9 Hz, 1 H, 3ꢀ
3
3
3
,4
3,5
3,6
3
H),7.76(d, 2H, 8.4 Hz), 7.73 (d, J=8.4 Hz, 2H, PyH), 8.08 (d,
J =8.4 Hz, 2H, PyH), 8.10 (ddd, J = 6.4, J = 1.2, J
.8 Hz, 2H, PyH), 8.28 (dt, J = J =4, J = 0.8 Hz, 2H,
3,4 4,5 4,6
PyH), 11.99 (br. s, 1 H, CSNH) ppm. IR (KBr): ν = 3310, 898
3
3
3
4
ꢀ
1
=
3,5
cm .
4,5
5,6
3
3
4
0
Nꢀ(4ꢀMethylphenyl)pyridineꢀ2ꢀthiocarboxamide(L2):
Yellow; Yield: 79%; M.p. 110ꢀ112°C. C H N S (228.31):
calcd. C 68.39, H 5.30, N 12.27, S 14.04; found C 68.10, H
PyH) ppm.δ (100MHz) 167.68, 162.92, 152.76, 149.81, 138.50,
c
1
3
12
2
1
30.43, 128.59, 126.22, 125.81, 124.10, 122.81, 118.99,17.92
1
ppm.
5
.57, N 12.36, S 13. H NMR (400 MHz, CDCl ): δ = 2.38 (s, 3
3
3
H, PhCH ), 7.26 (d, J = 8.4 Hz, 2 H, 3ꢀ and 5ꢀPhH), 7.46 (ddd,
3
[
Ni (L2) ] (2)
3
3
4
3
2
J4,5 =7.7, J = 4.8, J = 1.2 Hz, 1 H, 5ꢀPyH), 7.87 (dt, J =
3,4
5,6
3,5
3
4
3
Yield: 91.7%. M.P.250
°C Color: Yellow. Anal. Calc. for
J =7.7, J =1.8 Hz, 1 H, 4ꢀPyH), 7.93 (d, J =8.4 Hz, 2 H, 2ꢀ
and 6ꢀPhH), 8.54 (ddd, J = 4.8, J = 1.8, J = 0.9 Hz, 1
H, 6ꢀPyH), 8.80 (ddd, J =7.7, J = 1.2, J =0.9 Hz, 1 H, 3ꢀ
4
,5
4,6
3
4
5
C H N S Ni: C; 60.84, H; 4.32, N; 10.91, S; 12.46. Found: C;
26 22
4 2
5
,6
4,6
3,6
ꢀ
1
3
4
5
60.72, H; 4.29, N; 10.81, S; 12.52. IR (KBr, cm ) γ= 1634,
218. UVꢀVis in CHCl3: ꢉmax/nm (εmax/dm mol cm )
42(59,080), 267(60,140), 350(4613), 472(1296). H NMR
3
,4
3,5
3,6
3
ꢀ1
ꢀ1
1
2
PyH), 11.99 (br. s, 1 H, CSNH) ppm. IR (KBr): ν = 3240, 820
cmꢀ1.
1
This journal is © The Royal Society of Chemistry 2012
J. Name., 2012, 00, 1-3 | 11