Solid-phase synthesis, crystal structure, and quantum chemical calculation of a molybdenum(II) complex with bis(diethyldithiocarbamate)

Article abstract of DOI:10.1007/s10870-005-9060-6

The complex Mo(Et₂dtc)₂ [Et₂dtc: bis(diethyldithiocarbamate)] was synthesized by solid-phase reaction at room temperature and characterized by elemental analysis, powder XRD, IR, ¹H NMR and TG/DTA. Its crystal structure was determined by X-ray single crystal diffraction. The crystals are monoclinic with space group P2 ₁/c, a=0.61800(12)nm; b=1.1540(2)nm; c=1.1610(2)nm; β=95.78(3)°; V=0.8238(3)nm³; D _c=1.582g/cm ³; Z=2 F(000)=400; μ=1.285mm^-1; R=0.0703; wR=0.2330; GOF=1.060. The coordination geometry of Mo atom, by four S anions from Et ₂dtc ligand, is that of a slightly distorted planar square. Furthermore, the optimized geometry, charge distribution, and thermodynamic functions were calculated by quantum chemical method.

Full text of DOI:10.1007/s10870-005-9060-6

Journal of Chemical Crystallography, Vol. 36, No. 8, August 2006 (ꢀC 2006)
DOI: 10.1007/s10870-005-9060-6
Solid-phase synthesis, crystal structure, and quantum
chemical calculation of a molybdenum(II) complex
with bis(diethyldithiocarbamate)
(1)
(2)
(1)
(1)∗
Guang-Yu He, Feng-Li Bei, Hai-Qun Chen, and Xiao-Qiang Sun
Received April 7, 2005; accepted December 20, 2005
Published Online June 7, 2006
The complex Mo(Et2dtc)2 [Et2dtc: bis(diethyldithiocarbamate)] was synthesized by solid-
phase reaction at room temperature and characterized by elemental analysis, powder XRD,
1
IR, H NMR and TG/DTA. Its crystal structure was determined by X-ray single crys-
tal diffraction. The crystals are monoclinic with space group P21/c, a = 0.61800(12) nm;
◦
3
3
b = 1.1540(2) nm; c = 1.1610(2) nm; β = 95.78(3) ; V = 0.8238(3) nm ; Dc = 1.582 g/cm ;
−1
Z = 2 F(000) = 400; µ = 1.285 mm ; R = 0.0703; wR = 0.2330; GOF = 1.060. The coor-
dination geometry of Mo atom, by four S anions from Et2dtc ligand, is that of a slightly
distorted planar square. Furthermore, the optimized geometry, charge distribution, and
thermodynamic functions were calculated by quantum chemical method.
KEY WORDS: Mo(II) complex; diethyldithiocarbamate; solid-phase reaction; crystal structure; quantum
chemical calculation.
Introduction
Dialkyl-substituted dithiocarbamate (dtc)
The ability of dtc to bind to metals has been
known for many years. They can chelate with vir-
10
tually all transition elements. Water-soluble di-
alkyldithiocarbamate complexes have been tested
anions have been proven to be metal chelating
agents, which are highly versatile in separating
11
in various medical applications. In addition, di-
alkyldithiocarbamate sodium salts are better ex-
1
metals with gas chromatography. Their good per-
12
formance in liquid–liquid extraction and other
tracting agents for many transition metals. They
are good floating agents to novel metal ores and
2
analytical procedures makes them very attrac-
13,14
tive in identifying metals with gas chromatogra-
copper ores
as well. In this paper, we report
3
phy. Some of the dtc salts have shown interest-
a solid-phase reaction of molybdenum(II) com-
plex with bis(diethyldithiocarbamate) at room
4
,5
ing biological effects including anti-alkylation
and anti-HIV properties.6,7 They are also used as
effective antidotes for cadmium intoxication.8,9
1
temperature. Infrared and H NMR spectra were
acquired. And the crystal structure of molyb-
denum(II) bis(diethyldithiocarbamate) complex
(
1)
2)
[Mo(II)(Et dtc) ] has been determined. Further-
Key Laboratory of Fine Petro-Chemical Engineering, Jiangsu
Polytechnic University, Changzhou 213016, P.R. China.
Materials Chemistry Laboratory, Nanjing University of Science
and Technology,Nanjing 210094, P.R. China.
To whom correspondence should be addressed; e-mail:
chtt88@tom.com
2 2
more, the optimized geometry, charge distri-
bution and thermodynamic functions of title
complex Mo(II)(Et2dtc)2 were calculated by
quantum chemical method.
(
∗
4
81
1
074-1542/06/0800-0481/0 ꢀC 2006 Springer Science+Business Media, Inc.

4
82
He, Bei, Chen, and Sun
Table 1 Crystal Data and Structure Refinement for Title Complex
Empirical formula
Formula weight
Temperature (K)
C10H20MoN2S4
288.22
293(2)
˚
Wavelength (A)
0.71073
Crystal system
Space group
Monoclinic
P-1
Unit cell dimensions
a = 13.861(3),
b = 10.142(2), and
˚
a
c = 8.7320(17)A;
◦
b
c
d
β = 103.70(3)
˚
3
Volume (A )
1192.6(4)
4
Z
10
20
30
40
50
60
3
Calculated density (mg/m )
Absorption coefficient (mm 1) 0.129
1.605
2-Theta(degrees)
−
F(000)
Crystal size (mm )
Theta range for data collection
592
Fig. 1 The X-ray powder diffraction patterns of reactants
3
0.30 × 0.14 × 0.10
and products.
2.51–24.97
(
deg)
Limiting indices
− 16 ≤ h ≤ 15, − 12 ≤ k ≤ 0,
0
≤ l ≤ 10
Synthesis
Reflections collected
1118
Independent reflections
1118 [R(int) = 0.0000]
All chemicals were obtained from commer-
◦
Completeness to theta = 24.97 99.9%
cial source and used without further purification.
Absorption correction
Refinement method
Empirical
Full-matrix least-squares on F
1.114
2
ꢁ
Preparation of the N,N -diethyldithiocarba-
2
Goodness-of-fit on F
mate sodium [Na(Et dtc)]. To a stirred solution
2
Final R indices [I > 2σ(I)]
R indices (all data)
Largest diff. peak and hole
R1 = 0.0439, wR2 = 0.1125
of diethyl secondary amine (0.05 mol, Et NH is
2
R1 = 0.0503, wR2 = 0.1175
˚
−3
40% aqueous solution) in ethanol (5 ml), car-
bon disulfide (3.1 ml–0.052 mol), and sodium
hydroxide (50% aqueous solution 4 ml) were
added dropwise while keeping the temperature
0.358 and − 0.237 e. A
◦
below 4 C. After stirring for 4–5 h, volatiles
Experimental
were evaporated without heating. The pure prod-
uct [Na(Et2dtc)] was obtained after recrystal-
lization from ethanol. Yield 80–90%. Found: C,
30.19; H, 4.8; N, 7.6. Calcd. for the title com-
pound (C H N S Mo ): C, 30.60; H, 5.14; N,
Physical measurements
Elemental analysis for carbon, hydrogen,
and nitrogen were performed on Perkin-Elmer
10
20
2
4
1
2
40C instrument. The IR spectra were recorded
7.14.
Solid-phase synthesis of Mo(Et dtc) . At
−
1
in the 4000–400 cm region using KBr pellets
on a Nicolet 170SX FT spectrophotometer. Pro-
ton NMR spectra were obtained on a Bruker DRX
2
2
room temperature, the accurately weighed
ꢁ
white ligand N,N -diethyldithiocarbamate sodium
3
00 spectrometer using TMS as internal standard.
[Na(Et dtc)](a) and red NH MoO (b) (2:1) were
2
4
4
The TG/DTA data were acquired on a SDT2980
simultaneous for samples of approximately 10 mg
under a nitrogen atmosphere (150 ml/min)
carefully mixed in an agate mortar, and the
mixture was ground for 25 min. The primary
product (c) formed after the reaction mixture
turned green. The fine product (d) was ob-
tained by washing primary product with water.
Crystals, suitable for X-ray structure determi-
nation, were prepared after recrystallizing from
ethanol.
◦
at a heating rate of 20 C/min. The solid-
phase reaction was investigated by Bruker D8
ADVANCE powder XRD diffractometer. The sin-
gle crystal data were measured on Nonius-CAD-4
diffractometer.

Solid-phase synthesis, crystal structure, and quantum chemical calculation
483
Fig. 2 Molecular structure of the title compound with 50% probability of the
thermal ellipsoids.
Crystal structure determination
determination. The structure was solved by di-
rect methods using the SHELXTL program pack-
15
A green prismatic crystal with approximate
dimensions of 0.36 mm × 0.24 mm × 0.18 mm
was selected for data collection. The XRD
data were collected on a Nonius-CAD-4 diffrac-
tometer. Reflection data were measured at
age. All the non-hydrogen atoms were refined
2
on F anisotropically by full-matrix least squares
methods. All the hydrogen atoms were placed
in calculated positions assigned fixed isotropic
thermal parameters at 1.2 times the equivalent
isotropic U of the atoms to which they are at-
tached and allowed to ride on their respective
parent atoms. The contributions of these hy-
drogen atoms were included in structure-factor
calculations. The final least-square cycle gave
R = 0. 0439, wR = 0.1125 for 1035 reflections
2
93 K using graphite-monochromated Mo Kα
˚
radiation(λ = 0.71073 A). The ω − 2θ scan tech-
◦
nique was used with θ limit 2.49 < θ <
◦
2
4.96 . A total of 1443 independent reflections
were collected, of which 1079 observed reflec-
tions (I > 2σ(I)) were used for the structure
Fig. 3 Crystal packing of the title compound.

4
84
He, Bei, Chen, and Sun
˚
◦
Table 3 The Atomic Charges
Table 2 Bond Lengths (A) and Angles ( ) of the Title Compound
Atom
Charge
Atom
Charge
Mo(1)–S(1)
Mo(1)–S(1)#1 2.1981(16) S(1)–Mo(1)–S(2)
Mo(1)–S(2) 2.2013(16) S(1)#1–Mo(1)–S(2)
Mo(1)–S(2)#1 2.2013(16) S(1)–Mo(1)–S(2)#1
2.1981(16) S(1)–Mo(1)–S(1)#1
180.00(8)
79.35(6)
100.65(6)
100.65(6)
79.35(6)
180.00(12)
85.5(2)
Mo(1)
S(1)
C(3)
0.639
− 0.474
− 0.588
N(1)
C(1)
C(2)
− 0.289
0.453
− 0.284
S(1)–C(1)
S(2)–C(1)
N(1)–C(1)
N(1)–C(4)
N(1)–C(2)
C(2)–C(3)
C(4)–C(5)
1.720(6)
1.717(6)
1.305(8)
1.482(9)
1.499(9)
S(1)#1–Mo(1)–S(2)#1
S(2)–Mo(1)–S(2)#1
C(1)–S(1)–Mo(1)
C(1)–S(2)–Mo(1)
C(1)–N(1)–C(4)
85.5(2)
121.0(5)
121.1(6)
117.6(6)
is different with that of reactants (a and b). This
demonstrates that the reaction is brought to com-
pletion and the title complex can be synthesized
by environment-friendly solid-phase reaction at
room temperature.
1.494(13) C(1)–N(1)–C(2)
1.453(13) C(4)–N(1)–C(2)
2
2
2
with I>2σ(I), w = 1/[σ (F ) + (0.1241P) +
o
2
o
2
c
0
.0000P], where P = (F + 2F )/3. S = 1.060,
1
(
ꢀ/σ)
= 0.152, (ꢀρ)
= 0.831, (ꢀρ)
=
IR, H NMR spectra, and TG/DTA
max
max
min
−
1.053. Atomic scattering factors and anoma-
lous dispersion corrections were taken from In-
The four strong bands in the region from
2830 to 2960 cm of IR represent the stretching
16
−1
ternational Tables for X-Ray Crystallography.
Crystal data and refinement details are given in
Table 1.
vibration of C–H for CH . The v
stretching
2
C=N
−
1
vibration band is slightly shifted from 1610 cm
for the free ligand to the lower frequency
−
−1
1
22
1
1
600 cm for the complex. The strong peak of
Calculation method
202 cm shows the stretching vibration of C=S.
1
The H NMR (CDCl , TMS) spectrum of the free
3
Molecular modeling of Mo(Et dtc) was
2
2
ligand gives a triplet within 1.17–1.22 ppm for the
started by optimizing the molecular framework
obtained from the crystal structure with Hy-
protons of the CH and quadruplet around 3.98–
3
4
.00 ppm for the protons of the CH . The complex
2
17
perChem molecular modeling software us-
◦
was heated to 800 C in N atmosphere. The figure
2
18
ing MM + force field molecular mechanics.
After optimizing geometry, charge distribution
and thermodynamic functions were investigated
of TG/DTA analysis shows two weight-loss pro-
cesses. The complex began to lose 57.43% of its
◦
weight at about 74–321 C corresponding to the
1
9,20
using DFT-BLYP method,
with basic set of
loss of C H N S fragment (Calcd. 59.21%).
10
20
2 2
21
Double Numerical plus d-functions (DND). All
calculations were performed on Compaq Alpha
DS20E server and PIV 1.4G PC.
And finally the 9.80% loss of weight for S
◦
(
Calcd. 8.10%) from 414 to 798 C left the residue
of MoS.
Results and discussion
Description of the molecular and
crystal structure
Powder XRD characterization
A perspective view of the title compound
with atomic numbering scheme is shown in
Fig. 2. and a perspective view of the crystal
packing in the unit cell is shown in Fig. 3.
Atomic coordinates and equivalent isotropic dis-
placement parameters are listed in Table 1.
ꢁ
Powder XRD patterns of the ligand N,N -
diethyldithiocarbamate sodium (a), NH MoO
4
4
(b), primary product (c), and fine product of
Mo(Et dtc) (d) are shown in Fig. 1. The XRD
2
2
pattern of product (d) which can be seen in Fig. 1

Solid-phase synthesis, crystal structure, and quantum chemical calculation
485
Table 4 Thermodynamic Properties of Title Complex at Different
˚
of C1–N1 [1.305(8) A] has double-bond char-
acter, but slightly shorter than those observed
Temperatures
24
0
p,m
0
S
0
m
0
in a related structure. The other bond dis-
tances for the C–C in the ligand ring are in
good agreement with those of other corresponding
C
H
G
m
m
−1
−1
−1 −1
−1 −1
−1 −1
) (calmol K )
T (K) (calmol
K
) (calmol
K
) (calmol
K
25,26
200.00
298.15
400.00
500.00
600.00
700.00
800.00
58.884
77.125
95.095
128.102
189.921
164.300
compounds.
155.036
180.251
203.183
224.537
244.443
263.032
196.601
205.385
215.691
227.423
240.350
254.282
150.377
133.285
114.099
92.701
69.240
43.856
Charges distribution, thermodynamic
properties, and molecular orbit
110.603
123.648
134.575
143.810
The charge distribution of the title com-
plex is listed in Table 3. The charges on the
Mo(II) cation of 0.639 indicate that the charges
were transferred from the ligands to the Mo(II)
cation. Furthermore, the average charges of
1.257 on MoS of the complex demonstrate that
the charges on ligands were transferred toward
the coordinated center MoS . According to vi-
Selected bond lengths and bond angles are listed
in Table 2.
–
4
The Mo(II) ion is four-coordinated form-
4
ing a plane-square, i.e. MoS . The dithiocarba-
4
brational analysis and statistical thermodynam-
ics, the standard thermodynamic functions, heat
mate functions as a bidentate ligand coordinating
through the S atom with the Mo–S distance of
0
p m
0
˚
capacities (C ), entropies (S ), and enthalpies
2
.1981(16) and 2.2013(16) A. The MoS plane
4
0
m
(
H ) were obtained and are listed in Table 4.
is slightly distorted, with dihedral angles rang-
ing from 1.47(3) to –1.97(7). The four-membered
0
p
0
m
0
m
The magnitudes of C , S , and H increase with
0
m
MoS C ring is planar, with maximum devia-
temperature, but the G decreases with temper-
2
˚
tion of 0.013 A for C1 from the plane. The
ature. The molecular orbits HOMO and LUMO
were calculated, and their patterns are listed in
Fig. 4, which shows that the HOMO orbit mainly
appears on the Mo atom, while the LUMO orbit
was distributed averagely on ligand atoms and Mo
atom, indicating that electrons were transferred
from Mo atom to ligand atoms in the process of
excitation.
Mo1–S2 and S1–C1 bond lengths are longer than
those of Mo1–S1 and S2–C1, respectively. The
shorter Mo–S bond length (Mo1–S2) lies ad-
jacent to the C1–S2 bond, which is closer to
˚
the normal C=S bond length of 1.69 A. This
characteristic is also found and explained in de-
23
tail in the similar structure. The bond length
HOMO
LUMO
Fig. 4 Frontier molecular orbit of the title complex.

4
86
He, Bei, Chen, and Sun
Supplementary data
Further details of crystal struc-
A.; Maecel, A.; Petersen, E.A.; Whiteside, M.; zahradnik, J.;
Negron, C.; Boutitie, F.; Caraux, J.; Dupuy, J.M.; Saimi, R. J.
Am. Med. Assoc. 1991, 265, 1538.
8. Gale, G.R.; Atkins, L.M.; Walker Jr. E.M.; Smith, A.B.; Jones,
M.M. Ann. Clin. Lab. Sci. 1984, 14, 137.
ture determination can be obtained from the Cam-
bridge Crystallographic Data Centre, 12 Union Road,
Cambridge CB2 1EZ, UK (fax: + 44-1223-336033; e-mail:
deposit@ccdc.cam.ac.uk) on request. Deposition number CCDC
2
14324.
9. Shinobu, L.A.; Jones, S.G.; Jones, M.M. Acta Pharmacol. Tox-
icol. 1984, 54, 189.
1
0. Allen, F.H.; Kennard, O. Chem. Des. Autom. News 1993, 8,
Acknowledgement
Financial Support from the National Natural
3
1.
11. Bardaji, M.; Connelly, N.G.; Gimeno, M.C.; Jimenez, J.; Jones,
P.G.; Laguna, A.; Laguna, M. J. Chem. Dalton Trans 1994, 86,
1
163.
Science Foundation of China (No.21071021) and
the Open Foundation of Key Laboratory of Fine
Petro-Chemical Engineering of Jiangsu Polytech-
nic University are gratefully acknowledged
12. Xie, J.; Funakoshi, T.; Shimada, H.; Kojima, S. Res. Commun.
Mol. Pathol. Pharmacol. 1994, 86, 245.
1
1
1
1
3. Stary, J. The Solvent Extraction of Metal Chelate, Pergamon,
1964, p. 180.
4. Jian, F.-F.; Wang, Z.-X.; Bai, Z.-P.; You, X.-Z.; Fun, H.-K.;
Chinnakali, K.; Razak, I.A., Polyhedron 1999, 18, 3401.
5. Sheldrick, G.M. SHELXTL 97, Program for Crystal Structure
refinement, University of Gottingen, Germany, 1997.
6. Wilson, A.J. International Tables for X-ray Crystallography,
Vol. C, Dordrecht: Kluwer Academic Publishers, 1992; Tables
Reference
1
2
3
4
5
6
. Riekkola, M.L.; Makitie, O.; Sundberg, M. Kem. Kemi. 1979, 6,
4
.2.6.8 (pp. 219–222) and 6.1.1.4 (pp. 500–502) respectively.
5
25.
TM
1
7. HyperChem , Version 4.5 for Windows, Hypercube Inc.,
Waterloo, Canada, 1994.
. Thorn, G.D.; Ludwing, R.A. The Dithiocarbamate and Related
Compounds, Amsterdam: Elsevier, 1962.
. Riekkola, M.L.; Pakkanen, T.; Niinisto, L. Acta Chim. Scand
1
1
2
2
2
2
8. Allinger, N.L. J. Am. Chem. Soc. 1977, 99, 8127.
9. Becke, A.D. J. Chem. Phys. 1988, 88, 2547.
0. Lee, C.; Yang, W.; Parr, R.G. Phys. Rev. B 1988, 37, 786.
1. Delley, B. J. Chem. Phys. 1990, 92, 508.
2. Coville, N.J.; Neuse, E.W. J. Org. Chem. 1977, 42, 3485.
3. Lanfredi, A.M.M.; Ugozzoli, F.; Asaro, F.; Pellizer, G.; Marsich,
N.; Camus, A. Inorg. Chim. Acta. 1992, 192, 271.
4. Jian, F.F.; Bei, F.L.; Lu, L.D.; Yang, X.J.; Wang, X. et al. Acta.
Cryst. 2000, C56, e288.
1
983, A37, 807.
. Gringeri, A.; Keng, P.C.; Borch, R.F. Cancer Res. 1988, 48,
708.
5
. Pannacciulli, I.M.; Lerza, R.A.; Bogliolo, G.U.; Mencoboni,
M.P. J. Cancer 1989, 29, 371.
. Lang, J.M.; Touraine, J.L.; Trepo, C.; Choute, P.; Kirstetter,
M.; Falkenrodt, A.; Herviou, L.; Livrozet, J.M.; Retornaz, G.;
Tpuraine, F.; Renoux, G.; Renoux, M.; Musset, M. J. Carauk
and the AID-Imuthiol French Study Group, Lancet, 1988, 702.
. Hersh, E.M.; Brewton, G.; Abrams, D.; Bartlett, J.; Gill, P.;
Gorter, R.; Gottlieb, M.; Jonikas, J.J.; Landesman, S.; Levine,
2
2
2
5. Long, D.L.; Zeng, D.X.; Xin, X.Q.; Huang, X.Y.; Kang, B.S.
Synth. React. Inorg. Met-Org. Chem. 1996, 26, 723.
6. Zheng, H.G. Zeng, D.X.; Xin, X.Q.; Wong, W.T. Polyhedron
7
1
997, 20, 3499.