Bis (1,3-dithiole-2-one-4,5-dithiolato)antimonate(1-) salts, [Q][Sb(dmio)2]. Structural comparisons of [Q][Sb(dmio)2] and bis(1,3-dithiole-2-thione-4,5-dithiolato)antimonate(1-) salts, [Q][Sb(dmit)2]

Article abstract of DOI:10.1016/S0277-5387(02)01156-7

Bis(1,3-dithiole-2-one-4,5-dithiolato)antimonate(1-) salts, [Q][Sb(C₃OS₄)₂], [Q][Sb(dmio)₂] (3: Q = NEt₄, 1,4-dimethylpyridinium (DMP), PPh₄ or ferrocenyl-CH₂NMe₃) and

Full text of DOI:10.1016/S0277-5387(02)01156-7

Polyhedron 21 (2002) 2107ꢁ2116
/
www.elsevier.com/locate/poly
Bis(1,3-dithiole-2-one-4,5-dithiolato)antimonate(1-) salts,
[Q][Sb(dmio)2]. Structural comparisons of [Q][Sb(dmio)2] and bis(1,3-
dithiole-2-thione-4,5-dithiolato)antimonate(1-) salts, [Q][Sb(dmit)2]
John H. Aupers a, Zahid H. Chohan b, Nadia M. Comerlato c, R. Alan Howie a,*,
Alexandre C. Silvino c, James L. Wardell c, Solange M.S.V. Wardell d
a Department of Chemistry, University of Aberdeen, Meston Walk, Old Aberdeen AB24 3UE, UK
b Department of Chemistry, Islamia University, Bahawalpur, Pakistan
c Departamento de Qu´ımica Inorgaˆnica, Instituto de Qu´ımica, Universidade Federal do Rio de Janeiro, CP 68563, 21945-970 Rio de Janeiro, RJ, Brazil
d Departamento de Qu´ımica Orgaˆnica, Instituto de Qu´ımica, Universidade Federal Fluminense, 24020-150 Nitero´i, RJ, Brazil
Received 19 March 2002; accepted 12 June 2002
Abstract
Bis(1,3-dithiole-2-one-4,5-dithiolato)antimonate(1-) salts, [Q][Sb(C3OS4)2], [Q][Sb(dmio)2] (3: Qꢀ
(DMP), PPh4 or ferrocenyl-CH2NMe3) and bis(1,3-dithiole-2-thione-4,5-dithiolato)antimonate(1-) salts, [Q][Sb(C3S5)2],
[Q][Sb(dmit)2] (1: QꢀAsPh4 or NBu4) have been obtained from SbBr3ꢁNaSCN and [Q]2[Zn(dmio)2]or [Q]2[Zn(dmit)2]. The
crystal structures of (1: QꢀAsPh4 or NBu4) and (3: QꢀNEt4 and DMP) have been determined. In all cases, the Sb centres are 6-
/NEt4, 1,4-dimethylpyridinium
/
/
/
/
coordinated and, with the inclusion of the lone pair, are considered to have pseudo pentagonal bipyramidal structures. The
interanion interactions in these and related complexes are compared.
# 2002 Elsevier Science Ltd. All rights reserved.
Keywords: 1,3-Dithiole-2-thione-4,5-dithiolates; 1,3-Dithiole-2-one-4,5-dithiolates; Antimony(III); Crystal structures
1. Introduction
The 1,3-dithiole-2-thione-4,5-dithiolate
[C3S5]2ꢂ, (dmit), Fig. 1, has been extensively studied
as a ligand with both transition and main group metal
complexes [1] and binds to metal centres primarily
through the thiolato sulfur atoms forming, in the
majority of cases, chelate complexes. Intermolecular or
dimethylpyridinium (DMP), or PPh4] involves the
thione sulfur atoms, which connect the bis chelated
anions into arrays, varying in form with the cation [Q]ꢃ.
Metal-thione intermolecular interactions also arise in
dianion,
[NBu4][Bi(dmit)2] (2: Qꢀ
NEt4) [5], [(2: QꢀNEt4)×
AsPh4)×1/2DMSO] [4], it is the thiolato sulfur atoms
which take part in the secondary bonding. In addition to
these metalꢁsulfur interactions there can be weak
/
NBu4) [4], but in (2: Qꢀ
/
/
/
1/2Et2O] [5] and [(2: Qꢀ
/
/
interanionic secondary metalꢁsulfur interactions can
/
/
also occur to link the neutral or ionic complexes into
aggregated species. Such is the case with bis(1,3-dithiole-
2-thione-4,5-dithiolato)antimonate(1-) [Q][Sb(dmit)2],
(1) [2,3], and also bis(1,3-dithiole-2-thione-4,5-dithiola-
intermolecular SÁ Á ÁS contacts at distances less than the
˚
sum of the van der Waals radii of 3.60 A, which further
interconnect the anionic assemblies. In contrast, there
are no interanion interactions in the benzene-1,2-dithio-
lato complex [NEt4][Sb(1,2-S2C6H4)2] (CSD reference
code: HEGCUR) in which the benzene-1,2-dithiolato
ligand is merely chelating [7].
to)bismuthate(1-) complexes, [Q][Bi(dmit)2], (2) [4ꢁ
(Qꢀquaternary ammonium, arsonium cation, etc). The
secondary metalꢁsulfur bonding in [1: QꢀNEt4, 1,4-
/6]
/
/
/
Related to the dmit ligand is the 1,3-dithiole-2-one-
4,5-dithiolate dianion, [C3OS4]2ꢂ (termed dmio in this
paper, but also known as dmid) [1,8]. The structures of
few dmio complexes have been reported [1b]. As
* Corresponding author. Tel.: ꢃ
272-921
E-mail address: r.a.howie@abdn.ac.uk (R. Alan Howie).
/
44-1224-272-907; fax: ꢃ44-1224-
/
0277-5387/02/$ - see front matter # 2002 Elsevier Science Ltd. All rights reserved.
PII: S 0 2 7 7 - 5 3 8 7 ( 0 2 ) 0 1 1 5 6 - 7

2108
J.H. Aupers et al. / Polyhedron 21 (2002) 2107ꢁ2116
/
SbBr3 (0.36 g, 1 mmol) in acetone (20 cm3) and a
solution of [AsPh4]2[Zn(dmit)2] (1.22 g, 1 mmol) in
acetone (35 cm3). The reaction mixture was stirred for
30 min after the addition of [AsPh4]2[Zn(dmit)2], the
solvent removed by rotary evaporation and the crude
Fig. 1. Xꢀ
/
S: H2dmit; XꢀO: H2dmio.
/
expected, only small structural differences are found
between dmit and dmio complexes when these 1,2-
dithiolato ligands merely act as chelates, as in
product recrystallised from acetone to give dark greenꢁ
black crystals (blocks), m.p. 185ꢁ187 8C. Anal. for (1:
QꢀAsPh4). Found: C, 40.2; H, 2.3. C30H20AsS10Sb
requires C, 40.1; H, 2.2%. H NMR (DMSO-d6, 300
MHz): d: 7.8ꢁ
7.9(m, aryl-H). 13C NMR (DMSO-d6,
75.5 MHz): d: 121.5, 131.5, 133.7 and 134.9(aryl-C),
132.7(CꢀC), 212.2(Cꢀ C),
S). IR (KBr, cmꢂ1): 1437 (Cꢀ
1053, 1014(CꢀS), 883(Cꢁ
S). IR (CsI, cmꢂ1): 516, 482,
463, 398, 360, 351, 323, 289, 279, 270, 246, 223.
/
/
/
1
[Q][R2SnX(dmit)]
and
[Q][R2SnX(dmio)]
[9,10],
[Q]2[Sn(dmit)3] and [Q]2[Sn(dmio)3] [11], as well as
[Q][Zn(dmit)2] and [Q][Zn(dmio)2] [12]. However, when
the chalcogen atoms are involved in secondary bonding,
structural differences are realised as is the case with the
pair, Me2Sn(dmit) and Me2Sn(dmio) [9,13].
/
/
/
/
/
/
A series of bis(1,3-dithiole-2-one-4,5-dithiolato)anti-
monate(1-) complexes, [Q][Sb(dmio)2] (3) have been
2.1.3. Compound (1: Qꢀ
[NBu4]2[Zn(dmit)2]
The product was recrystallised from DMSO as dark
red crystals (needles): m.p. 168ꢁ170 8C. Anal. for (1:
QꢀNBu4). Found: C, 34.8; H, 4.9; N, 1.8.
C22H36NS10Sb requires C, 34.9; H, 4.8; N, 1.9%. 1H
NMR (DMSO-d6, 300 MHz): 0.93(t, 12H,
J(1Hꢁ1H)ꢀ
7.2 Hz, CH3), 1.30(m, 8H, CH2), 1.57(m,
8H, CH2), 3.18(t, 8H, H2Cꢁ
N). 13C NMR (DMSO-d6,
75.5 MHz): 13.5(CH3), 19.2(CH2), 23.1(CH2),
57.6(CH2), 132.4(CꢀC) and 211.5(CꢀS). IR (KBr,
S). IR
/
NBu4) from
prepared and the structures of two complexes, (3: Qꢀ
/
NEt4 and DMP), have been determined and are now
reported. These are compared with the structures of the
/
previously reported (1: Qꢀ
well as with those of the new compounds, (1: Qꢀ
/
NEt4, DMP and PPh4) as
NBu4
/
/
and AsPh4).
d
/
/
/
2. Experimental
d
/
/
cmꢂ1): 1437(Cꢀ
/
C), 1063, 1016(Cꢀ
/
S), 889(Cꢁ
/
2.1. General
(CsI, cmꢂ1): 526, 519, 462, 441, 390, 343, 329, 300,
288, 266, 246, 219.
NMR spectra were run on Bruker 250 and 300 MHz
instruments, IR spectra on Nicolet Magna 760 FTIR,
Philips Analytical PU9800 and Nicolet Fourier-trans-
2.1.4. Compound (3: Qꢀ
[NEt4]2[Zn(dmio)2]
The target product was recrystallised from acetone as
a dark greenꢁblack crystalline solid, m.p. 193ꢁ195 8C.
Yield: 0.57 g (67%). Anal. for (3: QꢀNEt4). Found: C,
/
NEt4) from
form spectrometers and UVꢁ
Cary 1E UVꢁVis instrument. Melting points (m.p.) were
measured on a MeltꢁTempII instrument and a Kofler
hotstage and are uncorrected. Elemental analyses were
obtained using a PerkinꢁElmer 2400 Instrument or
/
Vis spectra on a Varianꢁ
/
/
/
/
/
/
/
27.6; H, 3.5. C14H20NO2Sb requires C, 27.5; H, 3.3%.
1H NMR (DMSO-d6, 250 MHz): d: 1.2 (t of t, 12H, J
from Butterworth Laboratories Ltd, Middlesex. The
compounds, (ferrocenylmethyl)trimethylammonium io-
(1Hꢁ
J(1Hꢁ
(DMSO-d6, 63 MHz): d: 8.7(Me), 53.0(CH2N),
O). IR (CsI, cmꢂ1): 2075, 1660,
/
1H)ꢀ
/
7.2 Hz, Me of cation), 3.2 (q, 8H,
7.5 Hz, CH2N of cation). 13C NMR
/
1H)ꢀ
/
dide, [FcCH2NMe3]I [14], [Q]2[Zn(dmit)2] (Qꢀ
/NBu4
and AsPh4) and [Q]2[Zn(dmio)2] (QꢀNEt4, DMP,
/
FcCH2NMe3 and PPh4) [12,15] were prepared by
published procedures.
119.9(Cꢀ
/
C), 195.4(Cꢀ
/
1607, 1473, 1391, 1365, 1171, 1000, 883, 786, 755, 545,
462, 365, 338, 321, 280, 257, 172.
2.1.1. Synthesis of 1 and 3
These were prepared by a procedure similar to that
2.1.5. Compound (3: Qꢀ
[DMP]2[Zn(dmio)2]
The target product was recrystallised from acetone as
a dark greenꢁblack crystalline solid, m.p. 182ꢁ183 8C.
Yield: 0.58 g (68%). Anal. for (3: QꢀDMP). Found: C,
/
DMP) from
previously used for (1: Qꢀ
/
NEt4, PPh4 or DMP) [2,3].
Reactions between SbBr3ꢁNaSCN and [Q]2[Zn(dmit)2]
/
or [Q]2[Zn(dmio2] gave the target products in yields
generally greater than 60% after recrystallisation. The
/
/
/
procedure used for (1: Qꢀ/AsPh4) is given as an
26.7; H, 1.7; N, 2.5. C13H10NO2S8Sb requires C, 26.4;
H, 1.7; N, 2.4%. 1H NMR (DMSO-d6, 250 MHz): d: 2.6
(s, 3H, Me of cation), 4.3 (s, 3H, MeN of cation), 7.9 (d,
illustration.
2.1.2. Compound (1: Qꢀ/AsPh4) from
2H, J(1Hꢁ
J(1Hꢁ1H)ꢀ
d6, 63 MHz): d: 23.1(Me), 48.8(MeN), 120.0(Cꢀ
129.7, 146.2, 159.9 (aromatic-C), 195.4(CꢀO). IR (CsI,
/
1H)ꢀ
6.6 Hz, C2 and C6). 13C NMR (DMSO-
C),
/
6.2 Hz, C3 and C5), 8.8 (d, 2H,
[AsPh4][Zn(dmit)2]
/
/
To a solution of NaSCN×
/
2H2O (0.351 g, 3 mmol) in
acetone (20 cm3) was successively added a solution of
/
/

J.H. Aupers et al. / Polyhedron 21 (2002) 2107ꢁ
/2116
2109
cmꢂ1): 1771, 1660, 1641, 1605, 1517, 1471, 1295, 1189,
885, 877, 816, 803, 752, 695, 542, 486, 460, 366, 333, 318,
279, 252, 174, 154.
means of the programs DENZO [20] and COLLECT [21].
Correction for absorption was by means of SORTAV [22].
2.2.2. Structure solution and refinement
The direct methods approach of SHELXS-97 [23]
2.1.6. Compound (3: Qꢀ
[PPh4]2[Zn(dmio)2]
The target molecule was recrystallised from acetone as
a black crystalline solid, m.p. 173ꢁ175 8C. Yield: 0.88 g
(66%). Anal. for (3: QꢀPh4P). Found: C, 43.5; H, 2.6.
C30H20O2PS8Sb: requires C, 43.8; H, 2.4%. H NMR
(DMSO-d6, 250 MHz): d: 7.8 (m, 12H, m-Hꢃp-H), 8.0
(m, 8H, o-H). 13C NMR (DMSO-d6, 63 MHz): d: 118.6
(Cꢀ 88.5 Hz, Ci), 132.0
C), 120.0 (J(31Pꢁ13C)ꢀ
[J(31Pꢁ13C)ꢀ12.2 Hz, Cm], 136.1 (J(31Pꢁ13C)ꢀ
11.0
O). IR
/
Ph4P) from
provided solutions for the structures of (1: Qꢀ
and (3: QꢀNEt4 or DMP), while the structure of (1:
QꢀAsPh4) was solved by the heavy atom method using
SHELXS-86 [23]. Structure refinement in all cases was by
means of SHELXL-97 [24]. In the case of (1: QꢀAsPh4)
/
NBu4)
/
/
/
/
1
/
correction for extinction was applied with k in the
2
/
ꢄ
formula: Fc ꢀ
/
kFc[1ꢃ
/
0.001ꢅ
/
Fc l3/sin(2u)]1/4 taking
the value 0.0035(5). In all four cases, all non-H atoms
were refined anisotropically and in the final stages H
atoms were introduced in calculated positions and
refined with a riding model. Special action was required
to deal with disorder in two of the Bu groups of the
/
/
/
/
/
/
/
Hz, Co), 137.0(31Pꢁ
/
13C)ꢀ
/
2.2 Hz, Cp), 195.3(Cꢀ
/
(KBr, cmꢂ1): 1660, 1610, 1585, 1471, 1434, 1104, 995,
885, 752, 686, 526, 460.
counter cation of (1: Qꢀ
metric symmetry of the cation sites in (3: Qꢀ
(3: QꢀDMP). Further details of data collection and
/NBu4) and the centrosym-
/
NEt4) and
2.1.7. Compound (3: QꢀFcCH2NMe3) from
/
/
[FcCH2NMe3]2[Zn(dmio)2]
The target molecule was recrystallised from acetone as
structure refinement are available in Table 1.
a dark orangeꢁ
/
green solid, m.p. 203ꢁ
/
205 8C. Yield:
0.78 g, (60%). Anal. for (3: Qꢀ
/
FcCH2NMe3): C, 32.0;
3. Results and discussion
H, 3.0; N, 1.7. C20H20NO2FeS8Sb requires C, 32.4; H,
2.7; N, 2.0%. 1H NMR (DMSO-d6, 250 MHz): d: 2.9 (s,
9H, Me of cation), 4.2 (s, 5H, unsubstituted cp-H), 4.4
(s, 4H, substituted cp-H), 4.5 (s, 2H, CH2N). 13C NMR
(DMSO-d6, 63 MHz): d: 53.0(Me), 67.1(CH2N),
70.6(unsubstituted cp-C), 71.7, 73.6, 74.7(substituted
3.1. General
The dmit complexes, (1: Qꢀ
prepared from [Q]2[Zn(dmit)2] and SbBr3ꢁ
acetone, using a previously reported procedure [2]. A
related procedure was used to obtain (3: QꢀNEt4,
DMP, PPh4 or FcCH2NMe3) from [Q]2[Zn(dmio)2] and
SbBr3ꢁNaSCN. The complexes have little solubility in
non-coordinating solvents: the NMR spectra were run
in DMSO-d6 for this reason. The values of n(CꢀC) for 1
and 3 are generally found in the regions 1430ꢁ1443 and
1455ꢁ C)
1470 cmꢂ1, respectively, while the d13C(Cꢀ
NMR values are between 132.4ꢁ133.9 and 118.6ꢁ120.0
ppm, respectively. Spectral data for the CꢀS groups in 1
n(CꢀS) 1016ꢁ S) 211.5ꢁ213.3
1026 cmꢂ1 and d 13C(Cꢀ
ppm: values for CꢀO in 3 are n(CꢀO) 1660ꢁ1667 and
1605ꢁ O) 195.3ꢁ195.4 ppm.
1610 cmꢂ1and d 13C (Cꢀ
/
NBu4 and AsPh4), were
/
NaSCN in
cp-C), 119.9(Cꢀ
/
C), 195.3(Cꢀ
/
O). IR (KBr, cmꢂ1):
/
1666, 1610, 1479, 1467, 867, 825, 482, 464.
/
2.2. Crystallography
/
2.2.1. Data collection
/
For (3: Qꢀ
/
NEt4 or DMP) unit cell and intensity data
/
/
were obtained at 293 and 150 K, respectively, on the
Delft Instruments FAST diffractometer of the EPSRC’s
crystallographic service at Cardiff. Unit cells were
determined and the data collected using the routines
/
/
/
/
/
/
/
/
/
/
ENDEX, REFINE and MADONL of the MADNES software
[16] and data reduction carried out using ABSMAD [17].
/
/
/
Full procedural details are available elsewhere [18]. The
3.2. Crystal structures
triclinic cell determined initially for (3: QꢀNEt4) was
/
found to correspond to a C-centred monoclinic cell and
the cell dimensions were adjusted accordingly and the
intensity data re-indexed with the row-wise transforma-
In what follows, the geometry of the previously
published structures of (1: QꢀNEt4, DMP or PPh4)
/
[2,3] is described in terms of values obtained by the use
of PLATON [25] applied to cif data extracted from the
Cambridge Structural Database [26] at the Chemical
Database Service of the EPSRC at Daresbury [27] with
the atomic coordinates unchanged but with the atoms
relabelled for conformity with the new structures pre-
sented here.
tion matrix ꢂ
correction for absorption was made using XABS-2 [19].
Unit cell and intensity data for (1: QꢀNBu4) and (1:
QꢀAsPh4), both at 150 K, were obtained by means of
/
1 ꢂ
/
1 0; ꢂ
/
1 1 0; 0 0 ꢂ
/
1. In both cases
/
/
the Enraf Nonius KappaCCD area detector diffract-
ometer of the EPSRC’s crystallographic service at
Southampton. The entire process of data collection,
cell refinement and data reduction was accomplished by
Complexes 1 and 3 are, in all cases, ionic species
exhibiting only electrostatic cationꢁanion interactions.
/

2110
J.H. Aupers et al. / Polyhedron 21 (2002) 2107ꢁ
/2116
Table 1
Crystal data and structure refinement
1: QꢀAsPh4
1: QꢀNbu4
3: QꢀNet4
3: QꢀDMP
Empirical formula
M
C
897.73
30H20AsS10Sb
C22H36NS10Sb
756.87
150(2)
C14H20NO2S8Sb
612.54
293(2)
C13H10NO2S8Sb
590.45
150(2)
Temperature (K)
˚
Wavelength (A)
150(2)
0.71073
0.71073
monoclinic
P21/n
0.71073
monoclinic
C2/c
0.71073
triclinic
Crystal system
Space group
Unit cell dimension
triclinic
¯
¯
P/1/
P/
1
/
˚
a (A)
9.1083(1)
12.0855(2)
16.4877(3)
95.6559(6)
96.1007(6)
111.0647(13)
1665.67(4)
2
9.0802(4)
19.1957(8)
18.0213(10)
90
12.579(7)
12.373(7)
14.976(7)
90
8.7965(14)
10.741(3)
11.251(3)
89.310(14)
100.566(10)
109.903(10)
981.1(4)
2
˚
b (A)
˚
c (A)
a (8)
b (8)
g (8)
94.4590(15)
90
103.15(3)
90
3
˚
V (A )
Z
3131.6(3)
4
1.605
2270(2)
4
1.792
Dcalc (g cmꢂ3
Absorption coefficient (mmꢂ1
F(000)
)
1.790
2.464
888
1.999
2.266
580
)
1.563
1544
1.962
1224
Crystal colour
Crystal size (mm)
dark greenꢁ
0.36ꢅ0.20ꢅ0.06
3.21ꢁ30.54
ꢂ115h 511,
ꢂ155k 517,
ꢂ215l 523
25 181/8684 [0.0390]
85.2
/
black
dark red
0.25ꢅ0.05ꢅ0.03
dark greenꢁ
0.2ꢅ0.2ꢅ0.2
2.34ꢁ25.02
ꢂ145h 514,
ꢂ95k 513,
ꢂ165l B11
4259/1692 [0.0822]
84.1
/
black
dark greenꢁ
0.22ꢅ0.14ꢅ0.07
1.84ꢁ25.52
ꢂ105h 59,
ꢂ125k 512,
05l 511
/
black
u Range for data collection (8)
Index range
/
3.09ꢁ
/
27.51
/
/
ꢂ115h 511,
ꢂ245k 524,
ꢂ215l 523
19 918/7137 [0.1185]
98.9
Reflections collected/unique [Rint
Completeness to 2 u limit (%)
Absorption correction
]
3753/2752 [0.1443]
75.2
semi-empirical from
equivalents
0.864, 0.756
semi-empirical from
equivalents
0.959, 0.905
empirical (XABS-2.0) empirical (XABS-2.0)
Max/min transmission
Refinement method
0.641, 0.623
1.000, 0.582
full-matrix least-squares
on F2
full-matrix least-squares on full-matrix least-squares on full-matrix least-
F2
F2
squares
on F2
Data/restraints/parameters
Goodness-of-fit on F2
Final R indices [I ꢀ2s(I)] R1
wR2
8684/0/380
1.060
0.0366
7137/0/331
0.890
1692/0/138
1.065
2752/0/226
1.166
0.0522
0.0782
0 1647
0.1018
0.0526
0.1235
0.0591
0.1251
0.0712
0.1881
0.0761
0.1898
0.0876
0.0454
R indices (all data) R1
WR2
0.0922
0.0035(5)
Extinction coefficient
Largest difference in peak and hole 1.061 and ꢂ2.020
0.981 and ꢂ0.757
2.733 and ꢂ0.604
2.696 and ꢂ1.210
ꢂ3
˚
(e A
)
The cations have their usual geometries and are not
discussed further. The V-shape (Table 2) of the anions in
1 and 3 is shown, along with the numbering scheme
used, in Fig. 2. The bond lengths and angles within dmit,
in 1, and dmio, in 3, vary little from complex to
the Introduction, the complex, [NEt4][Sb(1,2-S2C6H4)2],
has been reported [7] to have non-interacting anions and
have a pseudo 5-coordinate Sb centre, if one coordina-
tion site is assumed to be occupied by the antimony lone
pair. The dithiolato ligands in [NEt4][Sb(1,2-S2C6H4)2]
complex. The central Cꢀ
and its attached S constitutes a planar entity with Sb
and the CꢀO or CꢀS atoms displaced from this plane by
varying amounts as shown in Table 2. In all complexes
each of the two chelating dmitꢁdmio ligands is asym-
metrically bound to Sb (Table 3) with shorter and longer
SbꢁS bond lengths in the range 2.4679(18)ꢁ2.527(3) and
2.529(3)ꢁ2.7311(6) A, respectively, both of which can be
compared with the PLATON [25] estimate of the sum of
/
C bond of each of the ligands
[7] are also asymmetrically bonded to Sb, with Sbꢁ
/
S
bond lengths of 2.4400(7) and 2.6093(7), in one chelate,
˚
and 2.4450(7) and 2.6266(8) A, in the other and are,
/
/
therefore, comparable with those in 1 and 3.
In all of the complexes 1 and 3 antimony also forms
two weaker bonds to chalcogen atoms of neighbouring
/
/
/
anions with Sbꢁ
/
S and Sbꢁ
/
O, in the range 3.271(4)ꢁ
/
˚
˚
3.285(3) A respectively (cf.
/
3.4968(16) and 3.131(5)ꢁ
/
PLATON [25] estimates of sums of van der Waals radii
for Sb and S and Sb and O and of covalent radii of Sb
˚
the covalent radii of Sb and S of 2.48 A. As indicated in

J.H. Aupers et al. / Polyhedron 21 (2002) 2107ꢁ
/2116
2111
Table 2
Out of plane displacements and interplanar and anion V-shape angles, Ip and V (A, 8)
a
˚
˚
Sb-oop(A): Sb out of
the ligand plane
˚
˚
C3-oop(A): C3 out of X-oop(A): thione-S or Ip (8): angle between the V (8): angle subtended at
the ligand plane
one-O out of the ligand ligand planes
plane
Sb by the two thione S in
(1) or two one-O in (3)
b
c
(1: QꢀNEt4)
(3: QꢀNEt4)
(1: QꢀPPh4)
0.247(2)
ꢂ0.188(3)
ꢂ0.096(1), 1.315(1)
0.095(11)
0.054(7)
0.292(4)
0.100(6)
86.52(12)
86.95(5)
67.29(6)
66.43(2)
105.85(11)
107.42(10)
84.5(2)
ꢂ0.003(5), 0.004(5)
0.005(3), 0.004(5)
0.003(1), ꢂ0.022(2)
0.0010(12), 0.0386(14)
(1: QꢀAsPh4) ꢂ0.0819(10),
ꢂ1.338(9)
83.39(1)
(1: QꢀNBu4) ꢂ0.099(2), 1.208(2)
0.031(5), 0.026(6)
0.103(3), 0.216(3)
63.35(5)
66.31(11)
76.41(9)
82.50(2)
120.8(2)
97.21(11)
b
(1: QꢀDMP)
(3: QꢀDMP)
0.606(1), 0.141(1)
0.030(4), 0.711(4)
0.047(10), ꢂ0.009(9) 0.091(3), ꢂ0.025(3)
ꢂ0.030(10),
ꢂ0.087(15)
0.024(9), ꢂ0.158(12)
a
Dmit and dmio ligand planes are defined by the CꢁC double bond and the attached S atoms.
Ref. [2].
Ref. [3].
b
c
˚
˚
and O of 4.06, 3.78 and 2.14 A, respectively). These link
the anions into 2D sheets or chains and in some cases,
along with SÁ Á ÁS or SÁ Á ÁO contacts shorter than the sum
3.317(5) A, respectively, in (3: Qꢀ
/
NEt4) complete the
connectivity.
In all of the other compounds discussed in this paper
the secondary SbꢁS and SbꢁO bonds interconnect the
anions to form chains. This is brought about in two
stages leading to three different situations (Fig. 3(bꢁd),
˚
/
/
of van der Waals radii (3.60 or 3.32 A, respectively), into
3D networks in a manner described in more detail
below.
/
In all of the structures discussed here, the anions are
confined to layers whose orientation is indicated com-
pound by compound in Table 3 and which are stacked
alternating with parallel layers of counter cations. The
simplest case, the anion layer in isostructural (1 and 3:
Tables 3 and 4). In the first stage one atom, X? in Table
3, i.e. a symmetry related equivalent of thione S5 in (1:
Qꢀ
(3: Qꢀ
/
NBu4, AsPh4, PPh4 and DMP) or of thiolato S2 in
DMP), bonds to Sb to form a centrosymmetric
/
dimer in which inevitably a pair of parallel and head to
tail ligands overlap to a greater or lesser extent (ring
QꢀNEt4), is clearly evident in Fig. 3(a). Here the
/
disposition of the anions is entirely due to the C-centred
nature of the unit cell so that all the anions within a
pairs aꢁ
contacts, Sbꢁ
/
a? in Table 4). The second stage involves further
/
Xƒ where Xƒ (Table 3) is a second and
single layer at zꢀ/1/4 or 3/4 point in the same direction
different symmetry related eqivalent, relative to the
original Sb, of the same thione S5 as before for (1:
along b. Adjacent anion layers are then related to one
another by crystallographic centres of symmetry or
equivalently by the operation of the c-glide of the space
group C2/c, thus inverting the orientation of the anions
Qꢀ
thione S, S10, or one-O, O1, in (1: Qꢀ
QꢀDMP), respectively. These connect the anions in (1:
QꢀNBu4, AsPh4 and PPh4) (Fig. 3(b)) and (3: Qꢀ
/NBu4, AsPh4 and PPh4), or symmetry equivalent
/DMP) [2] or (3:
/
from one layer to the next. Contacts between anion
˚
/
/
layers as S3Á Á ÁS5i (i: 1/2ꢂx, 1/2ꢂ
/
y, ꢂ
/
z) at 3.556(5) A
DMP) (Fig. 3(c)), to form linear double chains in which
the face to face ligands, including their chelate function,
are now m3 bridging species while the other ligands,
protruding on either side of the spine of the double
in (1: Qꢀ
/
NEt4) and S3Á/Á ÁS1i (i: ꢂ
/
x, ꢂ
/
y, 1ꢂ
/
z) and
S3Á Á ÁO1ii (ii: ꢂ
/
1/2ꢂ
/
x, ꢂ
/
1/2ꢂ
/
y, 1ꢂ
/z) at 3.550(3) and
Fig. 2. Atom arrangements and numbering systems for (a) (3: Qꢀ
/
NEt4) which, with S5 replacing O, applies equally well to (1: Qꢀ
/NEt4) [2] as
relabelled for comparison purposes; (b) (1: QꢀAsPh4, NBu4 and relabelled PPh4 [3] and DMP [2]), AsPh4 salt shown; (c) (3: Qꢀ
/
/
DMP).

2112
J.H. Aupers et al. / Polyhedron 21 (2002) 2107ꢁ2116
/
Table 3
a
˚
Bond lengths and angles (A, 8) about Sb in anions of 1 and 3
b
c
b
(1:QꢀNet4)
(3:QꢀNEt4) (1:QꢀNBu4) (1:QꢀAsPh4) (1:QꢀPPh4)
(1:QꢀDMP)
(3:QꢀDMP)
S(A)
S(B)
S(C)
S(D)
Xƒ
S1
S2
S1
S2
S1
S2
S1
S2
S1
S2
S1
S2
S1
S2
S1? [i]
S2? [i]
S5? [ii]
S5ƒ [iii]
S1? [i]
S2? [i]
O1? [iv]
O1ƒ [v]
S6
S7
S6
S7
S6
S7
S6
S7
S5
S6
S5? [vi]
S5ƒ [vii]
S5? [vi]
S5ƒ [viii]
S5?[ix]
S5ƒ [x]
S10? [xi]
S5? [xii]
O1? [vi]
S2? [viii]
X?
Bond lengths
SbꢁS(A)
SbꢁS(B)
SbꢁS(C)
SbꢁS(D)
SbꢁX?
SbꢁXƒ
SbÁ Á ÁSb?
Bond angles
2.496(3)
2.673(3)
2.496(3)
2.673(3)
3.271(4)
3.271(4)
2.4679(18)
2.666(2)
2.4679(18)
2.666(2)
3.131(5)
3.131(5)
2.4883(15)
2.6047(15)
2.4854(16)
2.7228(16)
3.4968(16)
3.3413(15)
4.3098(8)
2.4825(6)
2.6146(6)
2.5114(6)
2.7311(6)
3.3721(7))
3.4965(7)
4.0636(3)
2.4777(12)
2.6194(13)
2.5080(15)
2.7235(16)
3.4016(17)
3.5495(15)
4.0785(10)
2.502(3)
2.696(3)
2.527(3)
2.661(3)
3.336(4)
3.354(4)
2.527(3)
2.648(3)
2.478(3)
2.529(3)
3.285(3)
3.173(8)
3.6008(15)
ꢁ/
ꢁ/
ꢁ/
S(A)ꢁSbꢁS(B)
S(C)ꢁSbꢁS(D)
S(A)ꢁSbꢁS(C)
S(B)ꢁSbꢁS(D)
S(A)ꢁSbꢁS(D)
S(B)ꢁSbꢁS(C)
X?ꢁSbꢁXƒ
X?ꢁSbꢁS(A)
X?ꢁSbꢁS(B)
X?ꢁSbꢁS(C)
X?ꢁSbꢁS(D)
XƒꢁSbꢁS(A)
XƒꢁSbꢁS(B)
XƒꢁSbꢁS(C)
XƒꢁSbꢁS(D)
Direction of chain propagation
83.22(13)
83.22(13)
101.65(13)
158.86(13)
83.47(13)
83.47(13)
103.54(13)
82.44(13)
120.55(13)
155.98(13)
73.67(13)
155.98(13)
73.67(13)
82.44(13)
120.55(13)
83.12(6)
83.12(6)
84.45(5)
80.55(5)
97.17(6)
158.99(5)
77.97(5)
90.43(5)
101.90(3)
83.40(4)
78.25(4)
168.58(5)
110.64(3)
148.45(4)
66.67(4)
71.73(5)
126.70(4)
a
84.08(2)
80.34(2)
95.73(2)
84.1(2)
80.3(2)
95.7(2)
159.5(2)
77.2(2)
93.5(2)
108.2(2)
83.2(2)
86.8(2)
178.9(2)
99.1(2)
145.8(2)
65.1(2)
72.9(2)
129.8(2)
c
82.6(2)
82.9(2)
101.5(2)
155.6(2)
81.3(2)
82.5(2)
103.4(2)
86.1(2)
123.2(2)
154.1(2)
73.8(2)
156.5(2)
74.2(2)
79.4(2)
121.8(2)
a
83.70(8)
83.42(9)
96.52(9)
162.81(9)
82.54(9)
87.97(9)
115.84(15)
82.32(8)
106.15(7)
165.56(8)
82.15(8)
151.94(15)
71.06(14)
71.15(15)
119.47(14)
a
105.26(10)
157.47(18)
83.27(6)
158.72(2)
76.347(19)
93.61(2))
107.481(14)
83.837(18)
85.946(18)
179.409(19)
99.935(18)
145.204(18)
64.661(17)
72.656(18)
130.899(18)
a
83.27(6)
100.6(2)
86.16(10)
128.96(11)
147.36(10)
67.71(12)
147.36(10)
67.71(12)
86.16(10)
128.96(11)
d
e
¯
(011)
Orientation of chain
(001)
(001)
(010)
(010)
(100)
(011)
For all but (1: QꢀNEt4) and (3: QꢀNEt4), Xƒ is the atom which connects the anions into chains, and X? is the atom used to connect the anions in
centrosymmetric pairs with face to face ligands.
a
Symmetry operations as designated by roman numerals in square brackets: i: ꢂx, y, 1/2ꢂz; ii: xꢂ1/2, 1/2ꢃy, z; iii: 1/2ꢂx, 1/2ꢃy, 1/2ꢂz; iv:
ꢂ1/2ꢂx, 1/2ꢃy, 1/2ꢂz; v: 1/2ꢃx, 1/2ꢃy, z; vi: xꢂ1, y, z; vii: 1ꢂx, 1ꢂy, 1ꢂz; viii: 1ꢂx, 1ꢂy, ꢂz; ix: x, y, zꢂ1; x: 1ꢂx, ꢂy, 1ꢂz; xi: 1ꢂx,
y, z; xii; 1ꢂx, 2ꢂy, 2ꢂz.
Ref. [2].
b
c
Ref [3].
Direction of propagation of anion chains.
Form of plane parallel to anion (and cation) layers.
d
e
chain, are purely chelating. In (1: Qꢀ
/
DMP) [2], on the
significant contact between the chains but adjacent
anion layers are now related by the operation of the n-
other hand, the secondary SbꢁS10 bond, which was
/
overlooked in the original report of this structure,
creates a chain in the form of a succession of loops,
Fig. 3(d), and both ligands are now m2 bridges while still
chelating.
glide of the space group P21/n. In (1: QꢀDMP) [2],
/
there is no significant contact between the anion layers,
once again related by cell translation and, therefore, all
identical, where the looped chains are opposed face to
face but within the layers edge to edge contacts between
In the case of (1: Qꢀ
/
AsPh4) and (1: QꢀPPh4) [3],
/
the chains as S5Á Á ÁS5i (i: 1ꢂ
/
x, 3ꢂ
/
y, 2ꢂ
/
z) and S5Á Á ÁS9ii
which are isostructural despite the different labelling of
the cell edges, there is no significant contact between the
linear chains within or between the layers and adjacent
layers being related to one another purely by cell
˚
y, z) at 3.387(4) and 3.544(4)A, respec-
(ii: 1ꢃx, 1ꢃ
/
/
tively, are found (Fig. 3(d)). Also present here between
the chains within the layer is limited overlap of
centrosymmetrically related pairs of loop forming
translation are all identical. In (1: Qꢀ
/NBu4), which is
isostructural with (2: QꢀNBu4) [4], there is likewise no
/
ligands comprising C4ꢁ
/
C6 and S6ꢁ
/
S10 (ring pair bꢁb?
/

J.H. Aupers et al. / Polyhedron 21 (2002) 2107ꢁ
/2116
2113
Table 4
˚
Ring overlaps in terms of PLATON [25] pꢁp interaction parameters (A, 8) and lateral displacements, O
/
a
Ring pair [symmetry operation]
b
A
a
b
b?
B
B?
O
(1: QꢀNBu4)
(1: QꢀAsPh4)
(1: QꢀPPh4)
(1: QꢀDMP)
aꢁ
aꢁ
aꢁ
aꢁ
bꢁ
aꢁ
aꢁ
dꢁ
eꢁ
/
a? [vii]
a? [viii]
a? [x]
3.534
3.512
3.541
4.245
5.571
3.732
4.441
4.960
4.068
0
12.80
13.37
13.02
33.50
48.99
18.20
32.77
51.73
40.14
12.80
13.37
13.02
33.50
48.99
24.53
32.77
51.73
40.14
3.447
3.417
3.450
3.540
3.654
3.395
3.734
3.072
3.110
3.447
3.417
3.450
3.540
3.654
3.545
3.734
3.072
3.110
0.779
0.811
0.798
2.359
4.205
1.374
2.404
3.894
2.622
/
0
c
/
0
/
a? [xii]
0
/
b? [xiii]
c? [xiv]
a? [xv]
0
/
8.88
0
d
(3: QꢀDMP)
/
/
d? [x]
0
/e? [vii]
0
a
Rings defined as: (a) C1, C2, S4, C3, S3; (b) C4, C5, S7, C6, S6; (c) the DMP ring; (d) C4, C5, S8, C6, S7; (e) Sb, S1, C1, C2, S2. Symmetry
operations as in Table 3, plus: xiii: ꢂx, 1ꢂy, 1ꢂz; xiv: 1ꢂx, 2ꢂy, 1ꢂz; xv: 2ꢂx, 1ꢂy, ꢂz.
b
Calculated as (A2ꢂB2)1/2 for all except in (1: QꢀDMP) for the aꢁc? overlap, which was calculated as [A2ꢂ(BꢃB?)2/4]1/2. The overlap of rings x
/
and y with centroids Cgx and Cgy and points Fx (or Fy ) defined as the foot of the perpendicular from Cgx (or Cgy ) to the plane of ring y (or x) is
defined in the manner used by PLATON [25] in terms of the following: distances Cgx ꢁCgy (A); Cgx ꢁFx (B) and Cgy ꢁFy (B?) and angles between the
ring planes (a); Cgy ꢁCgx ꢁFx (b) and Cgx ꢁCgy ꢁFy (b?). If the rings are related to one another by the operation of a crystallographic centre of
/
/
/
/
/
/
/
symmetry they are by definition parallel to one another and hence aꢀ0, bꢀb? and BꢀB?.
Ref. [3].
c
d
Ref. [2].
in Table 4). More significant is pꢁ
DMP counter cation and the dimer forming ligand (ring
pair aꢁc? in Table 4). In (3: QꢀDMP) there is yet again
/
p overlap between the
S2? and S5 making an angle of 165.56(8)8 at Sb which
also shows a greater departure from the ideal than the
corresponding angles in the previous cases.
/
/
no significant contact between chains within or between
layers. However, in this case the use of thiolato S2 in
The location of the lone pair in isostructural (1 and 3:
Qꢀ
the earlier report on the structure of (1: Qꢀ
was considered to be in an equatorial site between the
two SbꢁS5 inter-anion bonds, i.e. directed along the
/NEt4) is not so simply or obviously determined. In
dimer formation promotes overlaps dꢁ
/
d? and eꢁe?
/
/NEt4) [2], it
(Table 4) within the essentially linear double chains.
/
crystallographic twofold axis (Fig. 4(a)). It then bisects
an angle of only 103.54(13)8 which appears extremely
small to accommodate it. However, the estimate of this
angle has been increased by positing [2] an increase to
that of f (Fig. 5), which is achieved if the inter-anion
bonds from Sb are directed toward p-orbitals on S (or
O) rather than directly toward the atoms. The equiva-
3.3. Geometry at Sb
In all of the complexes 1 and 3, Sb forms six bonds in
two groups as four strong intra- and two weaker inter-
anion bonds. Inclusion of the Sb lone pair results in
pseudo seven-coordinate geometry probably pentagonal
bipyramidal in form (see reference [28]). In contrast, the
antimony geometry in [NEt4][Sb(1,2-S2C6H4)2] is re-
ported to be pseudo trigonal bipyramidal [7]. The site of
the lone pair in compounds (1: QꢀNBu4 or AsPh4) is
assumed to be as shown in Fig. 4(b) and is exactly the
same, allowing for the changed atom numbering
lent bond angle in (3: Qꢀ
but the same argument regarding the use of f applies
here also. The difference between f and the XꢁSbꢁ
bond angle (XꢀS5 or O1) for the same orbitals
increases as the SbꢁX bond lengths decrease and the
inter-anion bonds SbꢁS5 and SbꢁO1 are the shortest of
/
NEt4) is still less at 100.6(2)8
/
/X
/
/
/
/
/
scheme, as that previously reported for (1: QꢀPPh4)
/
all inter-anion bonds found in 1 and 3. Thus the impact
of considering orbital overlap rather than direct atom to
atom vectors to determine bond direction and hence
bond angles will be greatest for these two complexes.
With the lone pairs in equatorial sites directed along the
twofold axis as just described the axial sites are then
occupied by S2 atoms which form the longest intra-
anion bonds in these complexes which is appropriate for
their perceived axial status. The angle they form, while
only about 1588, is, however, the largest subtended at
Sb.
[3]. In all three complexes, the lone pairs on centrosym-
metrically related Sb atoms are directed away from one
another on opposite sides of the centrosymmetric Sb2S2
rings and are in equatorial sites between S5? and S7. The
S5?ꢁ
than twice the ideal ligandꢁ
are perceived as sufficiently large [ꢀ
accommodate the lone pair. The axial atoms are S5ƒ
and S6 with angles at Sb [X?ꢁSbꢁS(C)] of 168.58(5)8,
179.409(19)8 and 178.9(2)8, respectively.
The situation in (3: QꢀDMP) is similar with the lone
/
Sbꢁ
/
S7 angles [Xƒꢁ
/
Sbꢁ
/
S(D) in Table 3] are less
ligand angle of 728 but
126.70(4)8] to
/
Mꢁ
/
/
/
/
/
Bearing in mind the twofold axial symmetry of these
last two complexes, alternative dispositions of the lone
pair between O1? and S6 (Fig. 4(d)). The angle O1?ꢁ
/
Sbꢁ
/
S6 is only 119.47(14)8 but still regarded as large enough
to accommodate the lone pair. The axial atoms are now
pair can also be envisaged. In (3: QꢀNEt4) the bond
/

2114
J.H. Aupers et al. / Polyhedron 21 (2002) 2107ꢁ2116
/
Fig. 3. Anion layers in (a) (3: Qꢀ
and in a generic manner i.e. lacking symmetry relationships which are instead given in Table 3. Cations are crudely represented either by N or for
DMP by the centroid. Atoms are shown as 50% ellipsoids [isotropic atoms for (1: QꢀDMP)] and the cell edges are labelled. Dashed lines represent
SbꢁX (Xꢀthione S or one-O) bonds or, in (d), SÁ Á ÁS contacts.
/
NEt4], (b) (1: Qꢀ
/
NBu4), (c) (3: Qꢀ
/
DMP) and (d) (1: QꢀDMP) [2]. In all cases only selected atoms are labelled
/
/
/
/
angles O1?ꢁ
/
Sb1ꢁ
/
S2ꢀ
/
O1ƒꢁ
/
Sb1ꢁ
/
S2?ꢀ
/
128.96(11)8, as-
atom pairs S1ꢁ
twofold axial symmetry in their disposition (Fig. 4(c)).
On this basis the situation in (1: QꢀDMP) with angles
S10?ꢁSbꢁS5? [103.4(2)8], S2ꢁSbꢁS7 [159.5(2)8], S10?ꢁ
SbꢁS7 [121.8(2)8] and S5?ꢁSbꢁS2 [123.2(2)8] relates to
that in (3: QꢀNEt4) and (1: QꢀNEt4) with corre-
/
S6, S2ꢁ
/
S7 and S5?ꢁ
/
S10? approximate
sociated with axial pairs O1ƒꢁ
/
S1 and O1?ꢁ
/
S1? with
/
trans-axial angle 147.36(10)8, are sufficiently large to
accommodate the lone pair more easily. If the lone pair
occupies only one of these sites the axial symmetry is
destroyed but, if the lone pair on Sb occupied an orbital
of d-type character, it would no longer concentrate
electron density towards a single notional coordination
/
/
/
/
/
/
/
/
/
/
sponding angles of similar magnitude.
site. A similar situation obtains for (1: Qꢀ
/
NEt4) and,
see below, (1: QꢀDMP). Dispersal or smearing out of
/
4. Supplementary material
the lone pair electron density in this way is also
consistant with the comparatively short inter-anion
Crystallographic data for the structural analyses have
been deposited with the Cambridge Crystallographic
Sbꢁ
While crystallographic symmetry does not apply in
the case of the remaining complex (1: QꢀDMP) the
/
X bonds observed in these complexes.
Data Centre, CCDC numbers 174409ꢁ/174412. Copies
/
of this information may be obtained free of charge from

J.H. Aupers et al. / Polyhedron 21 (2002) 2107ꢁ
/2116
2115
Fig. 4. Representations of the co-ordination of Sb including the stereochemically active lone pair (Lp and where appropriate the centrosymmetrically
related Lp?) in (a) (1: QꢀNEt4) and (3: QꢀNEt4); (b) (1: QꢀNBu4, PPh4 or AsPh4) [the example shown is (1: QꢀPPh4)]; (c) (1: QꢀDMP) and (d)
(3: QꢀDMP). In (a), (b) and (d) the suffix ‘a’ marks atoms related by symmetry to atoms without suffix. For clarity the ligands providing the
primary coordination of Sb are indicated only in terms of the 5-membered chelate rings thus formed.
/
/
/
/
/
/
National Data Collection Service of the EPSRC, now
at the University of Southampton, previously at the
University of Wales, Cardiff, and the expert assistance
of the staff there. The financial support of CNPq,
FAPERJ and FUJB, Brazil is gratefully acknowledged.
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