Synthesis and characterization of transition metal complexes of potassium 3-(pyridine-4-carbonylmethyl)-dithiocarbazate

Article abstract of DOI:10.1002/jccs.200200038

The preparation and characterization of some dipositive metal ion complexes derived from potassium 3-(pyridine-4-carbonylmethyl)-dithiocarbazate (PCDHK) are reported. The solid complexes of the composition ML·nH₂O (M=Cu(II), Co(II), Mn(II), Zn(II), Cd(II), Ni(II), Pb(II), L = PCD^-2, n = 0, 1, PCD^-2= PCDHK-K⁺-H⁺) and ML ₂·2H₂O (M=UO₂(IV), L=PCDH^-1, PCDH^-1=PCDHK-K⁺) have been characterized by elemental analyses, IR, UV, and ¹H NMR spectra. The IR spectral data indicate that PCDHK behaves as either a mononegative or binegative ligand and coordinates in a tridentate or bridging tetradentate manner.

Full text of DOI:10.1002/jccs.200200038

JournaloftheChineseChemicalSociety, 2002, 49, 251-254
251
Synthesis and Char ac ter iza tio on f Transition Metal Complexesof
Potassium3-(Pyridine-4-carbonylmethyl)-dithiocarbazate
Dong Liu (
), Su-Yan Liu (
), Xin-Ping Yang (
),
Peng-Fei Xu* (
) and Zi-Yi Zhang (
)
NationalLaboratoryofAppliedOrganicChemistry,LanzhouUniversity,Lanzhou730000,P.R. China
The prep a ra tion and char ac ter iza tion of some dipositive metal ion com plexes de rived from potassium
-(pyridine-4-carbonylmethyl)-dithiocarbazate (PCDHK) are re ported. The solid com plexes of the composi-
3
-
2
-2
tion ML ×n H
PCDHK-K -H ) and ML
2
O (M=Cu(II), Co(II), Mn(II), Zn(II), Cd(II), Ni(II), Pb(II), L = PCD , n = 0, 1, PCD =
+
+
-1
-1
+
2
×2 H
2
O (M=UO (IV), L=PCDH , PCDH =PCDHK-K )havebeencharacterizedby
2
1
elementalanalyses,IR,UV,and HNMRspectra.TheIRspectraldataindicatethatPCDHKbehavesaseither
a mononegative or binegative ligand and co or di nates in a tridentate or bridg ing tetradentate manner.
INTRODUCTION
Potassium3-(pyridine-4-carbonylmethyl)-dithiocar-
eth a nol and dry di ethyl ether. Yield 2.48 g, (99%), m.p. > 300
C.
°
bazate (PCDHK) has been re ported to func tion as an im por-
tant intermediate for the synthesis of heterocyclic com-
pounds. How ever, no work has been re ported con cern ing its
com plexes. It was found that PCDHK ex hib its in ter est ing
complexingcharacteristicswithtransitionmetals.Inthispa-
per, we re port the prep a ra tion and char ac ter iza tion of seven
new com plexes of PCDHK.
Synthesis of Complexes
A so lu tion of 0.502 g (2 mmol) PCDHK in bidistilled
wa ter (10 mL) was added with con stant stir ring to the metal
ac e tate (2 mmol) in bidistilled wa ter (5 mL). The re ac tion
mix ture was refluxed for one hour. The re sult ing solid was
filtered,washedwithbidistilledwater,ethanol,diethylether,
and then dried in a vac uum des ic ca tor over an hy drous cal-
ciumchloride.
1
EXPERIMENTAL
RESULTS AND DISCUSSION
Allchemicalsusedwereanalyticalgrade.Metalswere
2
determinedbyastandardliteratureprocedure. Car bon, H
All of the metal com plexes are quite sta ble in air and
soluble in dimethyl-formamide (DMF) and dimethyl sul-
foxide (DMSO), but in sol u ble in most com mon or ganic sol-
ventssuchaschloroform, ethanol, methanol, acetone, ben-
zene, anddichloromethane. Theircolorsandanalyticaldata
are re ported in Ta ble 1.
andNweredeterminedonanElementalVarioELelemental
analyzer. Infraredspectraofthecompoundswererecorded
on a Nicolet 170SX FT-IR spectrophotometer (KBr discs).
1
The H NMR spec tra were ob tained on a Bruker DRX-200
spectrometer(DMSO-d ). UV spec tra were re corded on a
6
Theinsufficientsolubilityofthecomplexesinsuitable
solvents precluded molecularweightdeterminationsand
growingofsinglecrystalsforX-raycrystallographicstudies.
Theformationofthecomplexesmayberepresentedby
thefollowingequations:
Shimadzu UV-240 spectrophotometer. Melting points were
taken on a Kofler melt ing point ap pa ra tus and are un cor-
rected. Dou ble dis tilled wa ter was used in pre par ing so lu-
tions.
Synthesis of the Ligand
bidistilled H2O
M(OAc)2 + PCDHK ¾ ¾ ¾ ¾ ¾ ®
A mix ture of 0.84 g (15 mmol) KOH and 1.37 g (10
mmol) isonicotinic hydrazide in ab so lute eth a nol (80 mL)
wasagitatedatroomtemperaturetoaffordaclearsolution.
Sub se quently, car bon disulfide 1.14 g (15 mmol) was added
and stirred for 16 hours. The solid was fil tered, washed with
M(PCD) ×n H
2
O¯ + KOAc + HOAc n = 0, 1
bidistilled H2O
UO2(OAc)2 + 2PCDHK ¾ ¾ ¾ ¾ ¾ ®
reflux
2 2 2
UO (PCDH) ×2 H O + 2KOAc

252 J. Chin. Chem. Soc., Vol. 49, No. 2, 2002
Liu et al.
Table 1. Analytical and Physical Data of the Complexes
m.p.
a
Elemental Analyses (%)
Yield
(%)
No.
Formula
Color
(
dec°c)
C
H
N
M
1
2
PCDHK
Cu(PCD)
OS
Mn (PCD)
OS
Zn (PCD)
OS
Cd (PCD)
OS
Yellow
Black
> 300
> 300
98
92
—
30.73
(30.60)
31.41
(31.59)
30.60
(30.39)
25.65
(25.97)
29.25
(29.20)
18.96
—
2.01
(1.82)
2.03
(1.88)
1.84
(1.81)
2.15
(1.55)
2.75
(2.43)
1.62
—
—
23.02
(23.13)
20.54
(20.66)
23.51
(23.66)
34.80
(34.76)
20.38
(20.40)
47.35
14.81
(15.30)
15.76
(15.79)
15.48
(15.20)
12.76
(12.98)
14.54
(14.60)
9.31
C
7
H
5
N
3
2
2
2
2
Cu
Mn
Zn
3
4
5
6
7
8
a
Brown
Yellow
Orange
Brown
Red
> 300
> 300
> 300
> 300
88
94
90
95
89
93
C
7
H
5
N
3
C
7
H
5
N
3
C
7
H
5
N
3
Cd
2
Ni(PCD) ×H O
CHNOSNi
Pb (PCD)×H
2
O
178-179
> 300
C
7
H
7
N
3
O
2
S
2
Pb
(19.27)
23.08
(23.01)
(1.60)
2.28
(2.19)
(9.63)
11.55
(11.51)
(47.46)
31.97
(32.19)
UO
2
(PCDH) ×2 H
2
2
O
Pale brown
C
14
H
18
N
6
O
6
S
4
U
The hydrated complexes lose the water molecule between 80-90 °C yielding anhydrous complexes. The loss
3
of the water molecule at this low temperature indicates that this water molecule is present in the lattice.
-
1
-1
InfraredSpectra
show two bands in the re gion 725 cm and 1270 cm which
5
The po si tions of in fra red bands of PCDHK (Scheme I)
are as signed tonc=s and a com bi na tion ofnc=s and nC-N, re-
and its com plexes have been pre sented in Ta ble 2.
spectively.
-
1
No band ex ists above 3500 cm or in the 2500-2600
-
1
Scheme I Struc ture of PCDHK
cm re gion due to nO-H and nS-H vibrations,respectively.The
ab sence of these bands in di cates that PCDHK ex ists in the
O
1
thioketo form. Also, the HNMRspectrum(DMSO-d
6
) of the
H
ligand shows no sig nals due to OH or SH con firm ing the pres-
ence of the thioketo form.
N
S
1
2
N
H
K
N
A comparison made between the IR spectra of the
ligand and its com plexes shows that PCDHK be haves as a
mononegative or binegative ligand and coordinates in a
bridgingtetradentateortridentatemanner.
S
The IR spec trum of PCDHK shows two bands at 3309
-
1
-1
1
2
cm and 3082 cm which are as signed tonN H and nN H vibra-
tions, re spec tively. The strong band at 1677 cm isattributed
The IR spectra of the complexes [(PCD)M×nH
2
O]
m
-
1
+
+
(where PCD equal to PCDHK-H -K ; M=Cu(II), Mn(II),
Zn(II), Cd(II), and Pb(II), n = 0, 1) show that the ligand be-
4
to car bonyl of the hy drox ide moi ety. The spectrum also
-1
Table 2. Infrared Spectral Bands for PCDHK and its Complexes (cm )
1
N H
2
N H
n
C=S
1
Compound
n
S-M
n
n
n
C=O
n
C=N
n
C-O
n
N-N
n
M-O
n
M-N
nC=S+nC-N
PCDHK
—
3082
—
—
—
—
—
—
3068
3309
3160
3190
3163
3181
3160
3184
3163
725, 1270
750, 1278
752, 1220
755, 1217
753, 1218
751, 1261
747, 1213
741, 1242
1677
—
—
—
—
—
—
1682
—
—
993
929
902
929
960
908
953
—
—
—
Cu (PCD)
Mn (PCD)
Zn (PCD)
Cd (PCD)
Ni(PCD) ×H O
Pb (PCD)×H
300
302
300
306
326
317
317
1608 1160
1612 1161
1600 1163
1610 1157
1632 1164
1594 1144
517
518
499
525
521
511
520
428
431
428
432
436
434
430
2
2
O
UO (PCDH)
2
2
×2 H
2
O
—
—

Metal Com plexes of PCDHK
J. Chin. Chem. Soc., Vol. 49, No. 2, 2002 253
haves inabinegativetetradentatemode, coordinatingthrough
the enolic ox y gen and the ni tro gen atom of the NH group to
one metal ion, and the an ionic sul phur atom and the ni tro gen
atom of the N=C group to an other metal cen ter with the loss
of a pro ton and a po tas sium ion. This mode of complexation
issuggestedbythefollowingevidence:(i)thedisappearance
of nC=O andnN-H withthesimultaneousappearanceofbandsin
The mode of complexation is sup ported by the fol low-
ing: (i) the car bonyl and N H bands re main and nC=N and nC-O
1
are ab sent.(ii) the thioketo bands re main at the same po si tion.
-
1
(iii) the ap pear ance of new bands at 520, 430 and 317 cm is
as sign able tonM-O, nM-N and nM-S, respectively. (iv) the ap-
-
1
pear ance of new bands in the re gion 3400-3500 cm is due to
the nOH of wa ter.
-
1
-1
the re gion 1594-1732 cm and 1144-1164 cm assignableto
6
n
C=N andnC-O,respectively. (ii) the thiocarbonyl bands in the
Electronic Spectrum
spec tra of all metal com plexes with re spect to these in the
ligand spec trum re main at the same po si tion sug gest ing that
the C-S group does not take part in complexation. (iii) the
The elec tronic spec trum of the ligand PCDHK shows
-
1
three bands at 36,941, 27,345 and 25,627 cm corresponding
to the p ® p* and n ® p* tran si tions of car bonyl and NH
-
1
-1
newbandsobservedintheregion499-525cm , 428-436 cm
and 300-326 cm are due to nM-O, nM-N and nM-S,respectively
group. The spec trum of [Ni(PCD)]H O shows two bands at
2
-
1
7
-1
-1
3
3
20,703 cm and 21,978 cm as sign able to the T
1
® T
1
(P)
3
3
(
Scheme II).
Scheme II
and T
1
® A
2
transitions,respectively,inatetrahedralstruc-
8
3
3
ture. The peak of the T
1
® T tran si tion was not found,
2
which may be cov ered by the peaks of the ligand. All these
val ues, to gether with the IR data, sug gest a tet ra he dral ar-
range ment of the do nor at oms around the metal ion.
O
M
1
H NMR Spectra
N
1
The H NMR spectra [DMSO-d
6
] show two broad
HN
.
nH O
2
N
peaks at 9.54 and 9.20 ppm for PCDHK and at 10.41 and
0.15 ppm for [(PCDH) UO ]2H O that are downfield from
TMS and that dis ap pear upon add ing D O. These peaks are
S
1
2
2
2
M
S
2
m
1
2
assigned to the protons of the N H and N H groups (in
Scheme I), re spec tively. A multiplet at 7.62-8.52 ppm is at-
trib uted to the pro tons of the pyridine moi ety. The H NMR
1
M=Cu, Mn, Zn, and Cd; n=0; M=Ni, and Pb, n=1.
spec trum of [(PCD)
posedstructure.
2
UO
2
]×2H O is con sis tent with the pro-
2
On the other hand, PCDHK may be have as a mono-
1
negative tridentate ligand via N H, carbonyloxygenandsul-
phuratomofthe-SKgroupwiththereplacementofthepotas-
sium atom from the -SK group as shown in Scheme III.
Biological Activities
Therepresentativecompoundswerescreenedfortheir
fungicidalactivitiesemployingtheagardiffusiontechnique.
ThepreliminaryresultsindicatedthatPCDHK,(PCD)Cuand
Scheme III
(
PCD)Zn ex hib ited mild in hib i tory ac tiv ity against plant
patho genic fungi such as gray mold of cu cum bers, sclerotium
rot of rape and brown leaf spot of pea nuts. The de gree of in hi-
bitionrangedfrom27.2~66.6%ataconcentrationof50ppm.
Furtherinvestigationsonthebiologicalactivitiesofthese
complexesareinprogress.
S
N
NH
S
NH
O
M
O
. 2H2O
ACKNOWLEDGEMENT
NH
S
S
HN
WethanktheNationalNaturalScienceFoundation(QT
Pro gram) of the PRC for its fi nan cial sup port.
N

254 J. Chin. Chem. Soc., Vol. 49, No. 2, 2002
Liu et al.
Received December 3, 2001.
dus try Press, 1982, p 616.
3
4
5
6
7
. Narang, K. K.; Singh, V. P. Synth. Reavt. Inorg. Met.-Org.
Chem. 1993, 23, 1187.
. Xanthopoulos, C. E.; Tzavellas, L. C.; Haristos, D. A.;
Katsoulos, G. A. Struct. Chem. 1994, 5, 1.
. Shallaby, A. H. M.; Khattab, M. A. K.; Moussa, M. N. El-D.
H.; Ibrahim, G. M. Acta Chim. Hung. 1986, 122, 61.
. Iskander, M. F.; El-Sayed, L.; Sadek, S.; Abu-Taleb, A.
Trans. Met. Chem. 1980, 5, 168.
. Nath, M.; Goyal, S.; Sharma, C. L.; Eng, G.; Whalen, D.
Synth. Re act. Inorg. Met.-Org. Chem. 1995, 25, 828.
Key Words
Preparation; Transition metals; Complexes;
Biologicalactivities.
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1
2
. Reid, J. R.; Heindel, N. D. J. Heterocycl. Chem. 1976, 13,
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