Benzylisopropyldithiocarbamate complexes of nickel with triphenylphosphine in the coordination sphere

Article abstract of DOI:10.1016/S0277-5387(99)00188-6

Nickel(II) benzylisopropyldithiocarbamate complexes of the composition [Ni(bzⁱPrdtc)₂], [NiCl(bzⁱPrdtc)(PPh₃)]·CHCl₃ and [NiX(bzⁱPrdtc)(PPh₃)] (X=Cl, Br, I, NCS; bz=C₇H₇, ⁱPr=C₃H₇, dtc=S₂CN^-, PPh₃=triphenylphosphine) have been synthesized. The complexes have been characterized by elemental analyses, IR and electronic spectroscopies, thermal analysis, magnetochemical and conductivity measurements. A single crystal X-ray analysis of the [NiCl(bzⁱPrdtc)(PPh₃)]·CHCl₃, [NiBr(bzⁱPrdtc)(PPh₃)] and [NiI(bzⁱPrdtc)(PPh₃)] confirms four-coordinated nickel in a distorted square-planar arrangement with the NiS₂PX chromophore. Elsevier Science Ltd.

Full text of DOI:10.1016/S0277-5387(99)00188-6

Polyhedron 18 (1999) 2879–2883
www.elsevier.nl/locate/poly
Benzylisopropyldithiocarbamate complexes of nickel with
triphenylphosphine in the coordination sphere
a
a ,
a
a
b
*
ˇ´
´ˇ
ˇ
´
´ˇ
´
Richard Pastorek , Jirı Kamenıcek , Zdenek Travnıcek , Josef Husarek , Norman Duffy
a
´
ˇ´ˇ
´
Department of Inorganic and Physical Chemistry, Palacky University, Krızkovskeho 10, 77 147 Olomouc, Czech Republic
bWheeling Jesuit University, 316 Washington Avenue, West Virginia, WV, USA
Received 6 April 1999; accepted 5 July 1999
Abstract
Nickel(II) benzylisopropyldithiocarbamate complexes of the composition [Ni(bziPrdtc)2], [NiCl(bziPrdtc)(PPh3)]?CHCl3 and
[NiX(bziPrdtc)(PPh3)] (X5Cl, Br, I, NCS; bz5C7H7, iPr5C3H7, dtc5S2CN2, PPh35triphenylphosphine) have been synthesized. The
complexes have been characterized by elemental analyses, IR and electronic spectroscopies, thermal analysis, magnetochemical and
conductivity measurements. A single crystal X-ray analysis of the [NiCl(bziPrdtc)(PPh3)]?CHCl3, [NiBr(bziPrdtc)(PPh3)] and
[NiI(bziPrdtc)(PPh3)] confirms four-coordinated nickel in a distorted square-planar arrangement with the NiS2PX chromophore.
Elsevier Science Ltd. All rights reserved.
1999
Keywords: Nickel(II) benzylisopropyldithiocarbamate complexes; Synthesis; Study; X-ray structure
1. Introduction
LANCASTER Co., nitromethane and triphenylphosphine
from FLUKA Co., the remaining reagents from LA-
CHEMA Co. All reagents were of p.a. purity.
Recently, the unsymmetrical Ni(II) dithiocarbamate
complexes of the type [Ni(NO)(HRdtc)(PPh3)] (R5Me,
Et,
Pr,
Bu,
Ph,
p-ClPh,
(R5Et,
p-MeOPh
[1],
[2],
2.2. Syntheses
[Ni(NCS)(HRdtc)(PPh3)]
Bu)
[NiX(HRdtc)(PPh3)] (X5Cl, Br, I, R5Me, Et, Pr, Bu, Ph,
p-ClPh, p-MeOPh [3] and [Ni(NO2)(HRdtc)(PBu3)] (R5
Me, Et, iPr, sBu) were studied [4]. However, no information
about the complexes of the [NiX(R1R2dtc)(PPh3) type
were found in the literature. Therefore, the aim of this
work was detailed study of the coordination compounds of
composition [NiX(bziPrdtc)(PPh3)], including the influ-
ence of X-donor atom on the structure and properties of
the complexes.
2.2.1. Preparation of [Ni(bziPrdtc)2 ]
The compound was prepared by the reaction of CS2 (50
mmol) with N-benzylisopropylamine (50 mmol) in EtOH
(25 cm3). A warm water solution of NiCl2?6H2O (25
mmol in 50 cm3) was added after 15 min. The deep-green
substance was formed and after standing for 1 h it was
filtered off, washed by warm water until negative reaction
on Cl2 ions and dried under an IR lamp at 408C (nearly
quantitative yield).
2. Experimental
2.2.2. Preparation of [NiX(bziPrdtc)(PPh3 )] (X5Cl, Br,
I, NCS)
2.1. Materials
These compounds were synthesized by the reaction of
suspension of fine pulverized complexes [Ni(bziPrdtc)2] (1
mmol) and [NiX2(PPh3)2] (1 mmol) [5] in CHCl3 (25
cm3). The mixture was stirred till all components were
dissolved. After filtration, an Et2O was added to creation a
slight turbidity. Then, the solution was left to crystallize at
N-benzylisopropylamine (97%) was purchased from
*Corresponding author. Tel.: 142-68-563-4353; fax: 142-68-522-
5737.
´ˇ
E-mail address: kamen@risc.upol.cz (J. Kamenıcek)
0277-5387/99/$ – see front matter
PII: S0277-5387(99)00188-6
1999 Elsevier Science Ltd. All rights reserved.

2880
R. Pastorek et al. / Polyhedron 18 (1999) 2879–2883
room temperature. The formed crystals were filtered,
washed by Et2O and dried under an IR lamp at 408C (yield
76–80%). Single crystals suitable for X-ray analysis were
obtained by recrystallization from a CHCl3 /Et2O mixture
(5:1).
PARST95 program [10]. All of important crystallographic
parameters are summarised in Table 1.
3. Results and discussion
Composition and analytical data for all complexes are
given in Table 2, and the important results of physico–
chemical studies are shown in Table 3.
All prepared compounds are diamagnetic and behave as
complex non-electrolytes [11]. Slightly increased values of
molar conductivities for [NiX(bziPrdtc)(PPh3)] could be
explain as a consequence of partial dissociation in the
solvent:
2.2.3. Physical measurements
The content of nickel was estimated by the chelatomet-
ric titration on murexid as an indicator, while chlorine and
¨
bromine were determined according Schoniger’s method
[6]. The elemental analyses (C, H, N, S) were performed
on an EA 1108 instrument (FISONS). All physico-chemi-
cal measurements were carried out using the same devices
as in the previous work [7].
[NiX(bziPrdtc)(PPh3)]á[Ni(bziPrdtc)(PPh3)]1 1 X2
2.3. X-ray crystallography
From Table 3, it follows that this dissociation increases
in the order NCS,Cl,Br,I. The results of magneto-
chemical and conductivity measurements show that nickel
atom is coordinated in the square-planar arrangement with
NiS4 chromophore in the case of the complex 1 and
NiS2PX in remaining complexes 2–6. This assumption is
supported by results of the electron spectroscopy; the
strong bands in the 15 700–20 500 cm21 region can be
attributed to the d–d electron transitions for Ni(II) square-
planar complexes [4,12]. The maxima between 28 700–
40 000 cm21 are connected with intraligand transitions in
X-ray measurements were performed on a KUMA KM-
4 diffractometer with graphite monochromated Mo Ka
˚
radiation (l50.71073 A) using an v/2u scan technique.
The structures were solved by the direct method using the
SHELX-97 program [8]. The structures were refined
anisotropically by the full-matrix least-square procedure on
F2 using SHELXL-97 program [9]. Most of H-atoms were
found from differential Fourier maps and they were refined
isotropically. Additional calculations were made using
Table 1
Crystal data and structure refinement for [NiX(bziPrdtc)(PPh3)], X5Cl, Br, I
Molecular formula
C30H30Cl4NNiPS2
C29H29BrNNiPS2
C29H29INNiPS2
Formula weight
Temperature (K)
Wavelength (A)
700.15
295(2)
0.71073
625.24
291(2)
0.71073
672.23
293(2)
0.71073
˚
Crystal system
Space group
Monoclinic
P21 /a
Triclinic
P1
Monoclinic
P21 /c
]
Unit cell dimensions
(A, 8)
a511.975(2)
b510.001(2)
c526.698(5)
a590
b596.080(3)
g590
3179(2); 4
0.2530.2030.07
3.6 to 25.5
115h514
2125k512
2325l520
14714
a510.1391(13)
b510.851(2)
c514.105(2)
a5109.08(2)
b591.512(12)
g5105.52(2)
1402.0(4); 2
0.7030.2530.20
1.5 to 27.6
2135h51
2135k514
2185l518
7429
a58.969(2)
b519.356(4)
c516.960(3)
a590
b596.46(3)
g590
2925.6(10); 4
0.430.430.3
1.6 to 25.1
215h510
2155k50
2165l516
4625
˚
3
˚
Volume (A ); Z
Crystal size (mm)
u range for data collection (8)
Index ranges
Reflections collected
Independent reflections
Data/restraints/parameters
Goodness-of-fit on F2
Final R indices [I.2s(I)]
5385 [R(int)50.1124]
5385/0/374
1.286
R150.0933
wR250.1933
R150.1756
wR250.2281
0.753;20.722
6496 [R(int)50.0238]
6496/0/432
1.019
R150.0318
wR250.0855
R150.0915
wR250.1037
0.462;20.591
3926[R(int)50.0376]
3926/0/345
1.027
R150.0302
wR250.0837
R150.0449
wR250.0900
0.630;20.358
R indices (all data)
Largest peak and hole
23
˚
(e.A
)

R. Pastorek et al. / Polyhedron 18 (1999) 2879–2883
2881
Table 2
The results of elemental analyses
Compound
Ni
C
H
N
S
Xa
Found (calcd.)%
1, [Ni(bziPrdtc)2]
11.3 (11.6)
9.8 (10.1)
8.5 (8.4)
9.7 (9.4)
9.0 (8.7)
9.3 (9.7)
51.7 (52.1)
59.9 (60.0)
51.9 (51.4)
55.4 (55.7)
52.3 (51.8)
59.7 (59.7)
5.5 (5.6)
5.0 (5.0)
4.3 (4.3)
5.1 (4.7)
4.7 (4.4)
4.6 (4.8)
5.2 (5.5)
2.1 (2.4)
1.8 (2.0)
2.2 (2.2)
2.4 (2.1)
4.8 (4.6)
24.7 (25.3)
11.5 (11.0)
9.8 (9.2)
9.7 (10.3)
9.1 (9.5)
2, [NiCl(bziPrdtc)(PPh3)]
3, [NiCl(bziPrdtc)(PPh3)]?CHCl3
4, [NiBr(bziPrdtc)(PPh3)]
5, [NiI(bziPrdtc)(PPh3)]
6, [Ni(NCS)(bziPrdtc)(PPh3)]
5.8 (6.1)
19.8 (20.2)
13.1 (12.8)
15.5 (15.9)
a X5Cl, Br.
Table 3
The results of physico–chemical studiesa
Compound
lM
(S cm2 mol21
IRb (cm21
)
UV/VIS
T c
(8C)
Color
)
(3103 cm21
)
n(CiS)
n(CiN)
1
2
4
5
6
2.6d
999 w
992 m
988 m
988 m
990 m
1540 w
1526 m
1516 w
1511 m
1515 w
15.7; 24.7; 28.7
19.5; 29.1
19.2; 28.7; 36.8; 37.6
19.4; 24.4; 29.2; 30.5; 36.8; 37.6
20.5; 28.6; 36.8
80
140
180
190
130
deep green
violet
violet
violet
red
6.4e
12.5e
13.2e
4.5e
a Compound 3 is not included (small amount of crystal available).
b In nujol.
c The beginning of thermal decomposition.
d Measured in dimethylformamide solution.
e Measured in nitromethane solution.
the S2CN2 group [13]. In the IR spectra of all the
complexes maxima at 1540–1511 cm21 and at 999–990
cm21 were observed. They are characteristic for dithio-
carbamates and can be assigned to [n(CiN)] and
[nCiS)], respectively [3,14]. Middle absorption peaks for
complex VI at 2080 cm21 [n(C;N)] and 835 cm21
[n(C–S)] may imply the assumption that the NCS
group is coordinated to the nickel via nitrogen atom
[15]. It was recently confirmed by X-ray analysis of similar
complexes [Ni(NCS)(Bu2dtc)(PPh3)] and [Ni(NCS)
(plddtc)(PPh3)] (Bu5n-C4H9, pld5C4H8) [2,16].
Table 4
i
˚
Selected bond lengths [A] for [NiX(bz Prdtc)(PPh3)] (X5Cl, Br, I)
Bond
Cl
Br
I
Ni(1)–S(1)
Ni(1)–P(1)
Ni(1)–S(2)
Ni(1)–X(1)
S(1)–C(1)
S(2)–C(1)
P(1)–C(21)
P(1)–C(31)
P(1)–C(11)
N(1)–C(1)
N(1)–C(40)
N(1)–C(2)
2.176(3)
2.195(3)
2.215(3)
2.189(3)
1.722(10)
1.714(11)
1.822(11)
1.819(11)
1.817(12)
1.326(14)
1.498(13)
1.472(13)
2.1851(10)
2.2023(9)
2.2205(8)
2.3153(7)
1.720(3)
1.711(3)
1.817(3)
1.825(3)
1.826(3)
1.316(4)
1.475(4)
1.499(4)
2.1882(12)
2.2094(12)
2.2087(12)
2.5257(8)
1.724(4)
1.709(5)
1.828(4)
1.851(4)
1.828(4)
1.325(5)
1.475(5)
1.479(6)
The thermal decomposition of [Ni(bziprdtc)2] starts at
808C. The TG-curve exhibits a plateau in the interval
410–4608C, which can be probably due to formation of
NiS2 (loss of mass found/calcd.573.7/73.8%). The de-
composition was not complete till 10008C. The thermal
degradations of remaining complexes 2–6 start at 130–
1908C and its thermal stability increases depending on X:
NCS,Cl,Br,I. The thermolysis is continual, without
transient intermediates.
The results of X-ray analysis of complexes 3, 4, and 5
(Tables 4 and 5; Figs. 1–3) confirm previous assumptions
of distorted square–planar arrangement of nickel in these
compounds. This fact is apparent from the different values
of the bond lengths and angles between nickel and
coordinated atoms of ligands and from deviations of atoms
from LSQ-plane Ni(1)S(1)S(2)P(1)X(1) (Table 6). The
relatively high value of R1 in the case 3 can be explained
by the poor quality of crystal (it was a great problem to
obtain crystals suitable for X-ray measurements and many
attempts to obtain a crystal of better quality were unsuc-
cessful). In contrast to 4 and 5, the structure of 3 contains
chloroform as solvent situated out of the coordination
sphere–the chlorine derivative without solvent 2 gives a
very poor crystals without a chance of solving the X-ray
structure.
As expected, the Ni(1)–X(1) bond lengths increase in
order to larger atomic radius in the series Cl,Br,I and
the length of Ni(1)–P(1) bond, too, whereas the
S(2)Ni(1)X(1) angles are slightly decreasing.Very interest-
ing is the fact that the Ni(1)–S(1) and Ni(1)–S(2) bond
lengths are not equivalent. For all three solved structures
are the Ni(1)–S(1) distances significantly shorter in com-

2882
R. Pastorek et al. / Polyhedron 18 (1999) 2879–2883
Table 5
Selected angles [8] for [NiX(bziPrdtc)(PPh3)], (X5Cl, Br, I)
Angle
Cl
95.29(12)
Br
92.14(3)
I
S(1)–Ni(1)–P(1)
S(1)–Ni(1)–S(2)
P(1)–Ni(1)–S(2)
S(1)–Ni(1)–X(1)
P(1)–Ni(1)–X(1)
S(2)–Ni(1)–X(1)
C(1)–S(1)–Ni(1)
C(1)–S(2)–Ni(1)
C(21)–P(1)–C(31)
C(21)–P(1)–C(11)
C(31)–P(1)–C(11)
C(21)–P(1)–Ni(1)
C(31)–P(1)–Ni(1)
C(11)–P(1)–Ni(1)
C(1)–N(1)–C(40)
C(1)–N(1)–C(2)
C(40)–N(1)–C(2)
N(1)–C(1)–S(2)
N(1)–C(1)–S(1)
S(2)–C(1)–S(1)
95.86(5)
78.13(5)
78.83(12)
170.18(13)
171.80(13)
92.66(12)
93.02(12)
86.8(4)
78.05(3)
169.49(3)
170.87(3)
96.84(3)
173.95(5)
169.13(3)
94.96(4)
91.06(4)
87.2(2)
92.87(3)
87.47(10)
86.53(10)
105.45(14)
103.12(14)
103.98(13)
109.25(10)
111.84(9)
121.79(9)
120.7(2)
119.0(2)
119.8(2)
126.9(2)
125.1(2)
85.8(4)
86.92(13)
103.1(2)
105.9(2)
103.0(2)
115.05(14)
115.16(12)
113.22(13)
119.7(4)
120.7(3)
119.6(3)
126.9(3)
125.3(3)
107.7(2)
101.0(5)
106.6(5)
106.6(5)
121.3(4)
115.1(4)
105.2(4)
119.4(9)
121.5(9)
119.1(9)
126.2(8)
125.4(8)
108.4(6)
Fig. 3. Molecular structure of [NiI(bziPrdtc)(PPh3)] with the atom
numbering scheme (thermal ellipsoids are drawn at 30% probability
level).
Table 6
Deviations of atoms from the LSQ Ni(1)S(1)S(2)P(1)X-plane in
i
˚
[NiX(bz Prdtc)(PPh3)], (X5Cl, Br, I) [A]
107.9(2)
Atom
Cl
Br
I
Ni(1)
S(1)
S(2)
P(1)
X(1)
0.045(4)
20.025(5)
20.001(14)
0.051(11)
0.049(11)
0.002(6)
0.005(6)
0.023(8)
20.108(8)
20.107(9)
0.012(9)
20.029(13)
0.021(14)
0.012(12)
20.003(4)
parison to Ni(1)–S(2) ones (see Table 4). This fact was at
first described for dithiocarbamates of the type
[NiX(R1R2dtc)(PPh3)] [2].
A significant deal of p-bonds in C(1)–N(1), C(1)–S(1)
and C(1)–S(2) was found. The lengths of the simple
˚
˚
s(N–C) and (C–S) bonds are 1.47 A and 1.81 A,
respectively [17]. For comparison, the appropriate values
˚
˚
are in pyridine 1.339 A, thiophene 1.718 A [18]. We have
found, that complexes 3, 4, 5 form hydrogen bonds
between the both S(1), S(2) atoms and C(2), C(40) atoms
respectively. Moreover, compound 3 exhibits intramolecu-
lar hydrogen bonds between Cl(1) and C(26); Cl(1) and
C(50) from solvent molecule. Some intermolecular con-
tacts between Cl(3) and C(22); Cl(4) and C(3) were
observed, too (Table 7, interpretation according [19]). This
fact can be explained by increased electronegativity of
chlorine in comparison to bromine and iodine.
Fig. 1. Molecular structure of [NiCl(bziPrdtc)(PPh3)]?CHCl3 with the
atom numbering scheme (thermal ellipsoids are drawn at 30% probability
level).
Supplementary data
Crystallographic data are available from the Cambridge
Crystallographic Data Centre (CCDC), 12 Union Road,
Cambridge CB2 1EZ, UK on request, quoting the deposi-
tion numbers 115882 (for 5), 115883 (for 4) and 115884
(for 3).
Fig. 2. Molecular structure of [NiBr(bziPrdtc)(PPh3)] with the atom
numbering scheme (thermal ellipsoids are drawn at 30% probability
level).

R. Pastorek et al. / Polyhedron 18 (1999) 2879–2883
2883
Table 7
Hydrogen bonds (distances in A and angles in 8) in [NiX(bz Prdtc)(PPh3)], (X5Cl, Br, I)
i
a
˚
D–H
D–A
H . . . A
/DHA
Cl
C(2)–H(2)
0.96(22)
C(40)–H(40A)
1.03(21)
C(26)–H(26)
0.96(24)
C(50)–H(50)
1.10(20)
C(3)–H(3B)
0.96(28)
C(22)–H(22)
1.11(26)
C(2) . . . S(1)
3.10(9)
C(40) . . . S(2)
3.08(7)
C(26) . . . Cl(1)
3.44(18)
C(50) . . . Cl(1)
3.46(22)
C(3) . . . Cl(4)
3.71(17)
C(22) . . . Cl(3)
3.76(29)
H(2) . . . S(1)
2.59(2)
H(40A) . . . S(2)
2.55(8)
H(26) . . . Cl(1)
2.72(3)
H(50) . . . Cl(1)
2.94(4)
H(3B) . . . Cl(4)
2.90(38)
H(22) . . . Cl(3)
2.77(11)
C(2)–H(2) . . . S(1)b
112.5(1.9)
C(40)–H(40A) . . . S(2)b
111.5(1.7)
C(26)–H(26) . . . Cl(1)b
131.8(1.2)
C(50)–H(50) . . . Cl(1)b
109.4(1.0)
C(3)–H(3B) . . . Cl(4)c
142.7(1.4)
C(22)–H(22) . . . Cl(3)c
147.9(4.4)
Br
C(2)–H(2)
0.96(28)
C(40)–H(40A)
0.96(6)
C(2) . . . S(1)
3.04(2)
C(40) . . . S(2)
3.10(2)
H2 . . . S1
2.50(13)
H40A . . . S2
2.61(26)
C(2)–H(2) . . . S(1)b
115.5(3.0)
C(40)–H(40A) . . . S(2)b
111.8(2.8)
I
C(2)–H(2)
0.90(48)
C(40)–H(40B)
0.87(28)
C(2) . . . S1
3.07(1)
C(40) . . . S2
3.08(5)
H2 . . . S1
2.56(18)
H40B . . . S2
2.49(34)
C(2)–H(2) . . . S(1)b
116.9(8.8)
C(40)–H(40B) . . . S(2)b
125.2(7.6)
a D5donor; A5acceptor.
b Intramolecular contacts.
c Intermolecular contacts.
[8] G.M. Sheldrick, SHELXS-97; enhanced version of SHELX-S, Acta
Crystallogr., Sect. A 46 (1990) 467.
Acknowledgements
[9] G.M. Sheldrick, SHELXL-97; Program for Crystal Structure Refine-
We thank the Grant Agency of the Czech Republic
(grant No. 203/99/0067) and FRVS (grant No. 31702007/
1999) for financial support.
¨
ment, University of Gottingen, 1997.
ˇ
[10] M. Nardelli, PARST 95 J, Appl. Cryst. 28 (1995) 659.
[11] W.J. Geary, Coord. Chem. Rev. 7 (1971) 81.
[12] A.B.P. Lever, Inorganic Electronic Spectroscopy, Elsevier, Am-
sterdam, 1968, p. 343.
[13] C.A. Tsipis, I.J. Meleziadis, D.P. Kessissoglou, G.A. Katsoulos,
Inorg. Chim. Acta 90 (1984) L19.
References
[14] S.V. Larionov, L.A. Patrina, I.M. Oglezneva, E.M. Uskov, Koord.
Chim. 10 (1984) 92.
[15] I.E. Cernikova, I.A. Chartonik, D.S. Umrejko, A.B. Kavrikov, V.I.
[1] C.A. Tsipis, D.P. Kessissoglou, G.E. Manoussakis, Chim. Chron.
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