Coordination of 4-mercapto-1,2-dithiole-3-thione heterocycles to ruthenium(II) and molybdenum(VI) centres

Article abstract of DOI:10.1016/j.ica.2009.09.015

Deprotonation of 4-mercapto-1,2-dithiole-3-thiones with NEt₃ followed by reaction with [Ru(H)(Cl)(CO)(PPh₃)₃] affords virtually quantitative yields of turquoise [Ru(H)(RC₃S₄)(CO)(PPh₃)₂] (R = Ph, Mes) in which the heterocycle is bound as a bidentate uninegative ligand through the two exocyclic sulfur atoms. The presence of both possible isomers in each case is indicated by NMR spectroscopy. Reaction of the 4-mercapto-1,2-dithiole-3-thiones with [MoO₂(acac)₂] results in displacement of the acac ligands and formation of [MoO₂(RC₃S₄)₂]. The crystal structures of [Ru(H)(MesC₃S₄)(CO)(PPh₃)₂] and [MoO₂(MesC₃S₄)₂] have been determined.

Full text of DOI:10.1016/j.ica.2009.09.015

Inorganica Chimica Acta 363 (2010) 173–178
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Inorganica Chimica Acta
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Coordination of 4-mercapto-1,2-dithiole-3-thione heterocycles to ruthenium(II)
and molybdenum(VI) centres
*
Harry Adams, Anna M. Coffey, Michael J. Morris
Department of Chemistry, University of Sheffield, Sheffield S3 7HF, UK
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 19 May 2009
Received in revised form 14 August 2009
Accepted 2 September 2009
Available online 8 September 2009
Deprotonation of 4-mercapto-1,2-dithiole-3-thiones with NEt3 followed by reaction with [Ru(H)(Cl)-
(CO)(PPh3)3] affords virtually quantitative yields of turquoise [Ru(H)(RC3S4)(CO)(PPh3)2] (R = Ph, Mes)
in which the heterocycle is bound as a bidentate uninegative ligand through the two exocyclic sulfur
atoms. The presence of both possible isomers in each case is indicated by NMR spectroscopy. Reaction
of the 4-mercapto-1,2-dithiole-3-thiones with [MoO2(acac)2] results in displacement of the acac ligands
and formation of [MoO2(RC3S4)2]. The crystal structures of [Ru(H)(MesC3S4)(CO)(PPh3)2] and [MoO2-
(MesC3S4)2] have been determined.
Keywords:
Ruthenium
Molybdenum
Sulfur
Ó 2009 Elsevier B.V. All rights reserved.
1,2-Dithiole-3-thione
1. Introduction
sulfur atom of the C@S group. In addition we show that deprotona-
tion of the heterocyclic thiol products also provides an effective
Compounds which contain the 1,2-dithiole-3-thione ring sys-
tem are currently attracting attention as chemopreventive agents
against various types of cancer. One such compound, Oltipraz (4-
methyl-5-(2-pyrazinyl)-1,2-dithiole-3-thione), shown in Fig. 1,
which was originally developed as an anti-schistosomiasis treat-
ment, is currently undergoing a large scale clinical trial in the Qi-
dong region of China, an area associated with a high incidence of
aflatoxin-induced liver cancer [1]. Other compounds containing
the 1,2-dithiole-3-thione ring are known to have chemopreventive
properties which are at least as good as, if not better than, Oltipraz
[2].
route to complexes of this type. Previous studies of the coordina-
tion chemistry of the 1,2-dithiole-3-thione ring system have lar-
gely concentrated on the 4,5-dithiolate derivative (often known
as dmt), which can be prepared by thermal isomerisation of the
readily prepared dmit dianion (Steimecke rearrangement) as
shown in Scheme
2 [6]. Bis-chelate complexes of the type
[NBu4]2[M(dmt)2] (M = Ni, Pd, Pt, Cu) can then be prepared in
which the dianionic ligand bonds through the exocyclic 4,5-dithi-
olate unit, in the same manner as in the dmit isomers [7].
2. Results and discussion
One of the drawbacks of such compounds is that their synthesis
often involves toxic and malodorous sulfurising reagents such as
P2S5, Lawesson’s reagent, or H2S [3]. We recently reported a novel
2.1. Ruthenium complexes
route to 4-mercapto substituted 1,2,-dithiole-3-thiones
4 by
Addition of one equivalent of [RuH(Cl)(CO)(PPh3)3] to solutions
of the anions 3 (R = Ph or Mes) prepared in situ from the appropri-
ate lithium acetylide, carbon disulfide and sulfur, either at room
temperature or at ꢀ78 °C, rapidly afforded a dark turquoise solu-
tion from which the new highly coloured blue-turquoise com-
plexes [Ru(H)(RC3S4)(CO)(PPh3)2] (5 R = Ph; 6 R = Mes) could be
isolated by column chromatography (Scheme 3). The yields of both
compounds are high (88% for 5 and 72% for 6). The only other prod-
uct detected was triphenylphosphine sulfide (identified by 31P
NMR and mass spectroscopy), formed by the liberated PPh3 react-
ing with the excess of sulfur involved in the synthesis of the
heterocycle. Deprotonation of the preformed 4-mercapto-1,2-
dithiole-3-thione derivatives with triethylamine followed by addi-
tion of [RuH(Cl)(CO)(PPh3)3] produced slightly improved yields of 5
sequential treatment of alkynyl lithiums with carbon disulfide
and elemental sulfur (Scheme 1) [4]. We also showed that the first
intermediates in this reaction, the alkynyl dithiocarboxylate anions
RCBCCSꢀ2 2, were sufficiently stable in solution at room tempera-
ture to be coordinated to ruthenium(II) centres by reaction with
[RuH(Cl)(CO)(PPh3)3] or [Ru(CPh@CHPh)(Cl)(CO)(PPh3)2] [5].
In this paper we demonstrate that a further intermediate in this
synthesis, the 4-mercapto-1,2-dithiole-3-thione anions 3, can also
be isolated by coordination to ruthenium, and that they coordinate
as bidentate ligands through the 4-mercapto substituent and the
* Corresponding author. Tel.: +44 114 2229363; fax: +44 114 2229346.
E-mail address: M.Morris@sheffield.ac.uk (M.J. Morris).
0020-1693/$ - see front matter Ó 2009 Elsevier B.V. All rights reserved.
doi:10.1016/j.ica.2009.09.015

174
H. Adams et al. / Inorganica Chimica Acta 363 (2010) 173–178
mer ratios is unknown, but seems likely to be due to steric factors.
The FAB mass spectra of both complexes showed appropriate
molecular ion envelopes.
Diffusion of heptane vapour into an ethyl acetate solution of 6
gave large turquoise blocks suitable for X-ray diffraction. The
molecular structure is shown in Fig. 2 with selected bond lengths
and angles collected in Table 1. As expected the molecule adopts
an octahedral geometry with the two PPh3 ligands in mutually
trans positions; the P(1)–Ru(1)–P(2) angle is 164.40(5)°. The het-
erocyclic ligand is coordinated in a bidentate manner through
the thione sulfur atom S(1) [Ru(1)–S(1) 2.4341(16) Å] and the thio-
late sulfur atom S(2) [Ru(1)–S(2) 2.4585(16) Å]. The C@S bond of
the thione unit apparently retains complete double bond character,
as shown by the C(2)–S(1) distance of 1.659(6) Å compared to the
value of 1.651(3) Å for the corresponding bond in the structure of
PhCSSC(@S)C(SMe); this can also be compared with the C(3)–S(2)
single bond of the thiolate group in 6 which is 1.740(6) Å. The crys-
tal chosen for study consists exclusively of the isomer in which the
thione sulfur is trans to the hydride ligand and the thiolate sulfur
trans to the carbonyl ligand, rather than vice versa; however it is
not known whether this corresponds to the major or minor isomer
in solution.
Fig. 1. Structural formula of Oltipraz.
(93%) and 6 (89%). However since the isolated yields of the thiones
4 are only about 50%, the in situ reaction gives a better overall yield.
Characterisation of 5 and 6 followed from their spectroscopic
data. Each complex shows one strong m(CO) absorption in the IR
spectrum (at 1930 cmꢀ1 for 5, 1932 cmꢀ1 for 6). Apart from phenyl
peaks the 1H NMR spectrum of 5 contains two triplet hydride res-
onances at d ꢀ9.54 (JHP = 18.0 Hz) and d ꢀ9.86 (JHP = 17.5 Hz), indi-
cating the presence of two isomers in a ratio of 97.7:2.3. Similarly
the 1H NMR spectrum of 6 also contains two hydride signals, at d
ꢀ9.47 (JHP = 19.5 Hz) and ꢀ10.43 (JHP = 18.5 Hz) in a ratio of
56:44. The 31P NMR spectra of both compounds also indicate the
presence of two isomers. The origin of the large difference in iso-
Scheme 1. Formation of 4-mercapto-1,2-dithiole-3-thiones from alkynes [4].
Scheme 2. Synthesis and coordination of dmt (4,5-dimercapto-1,2-dithiole-3-thione dianion) [6,7].
Scheme 3. Synthesis of ruthenium complexes.

H. Adams et al. / Inorganica Chimica Acta 363 (2010) 173–178
175
Fig. 2. Molecular structure of complex 6 in the crystal (ORTEP plot, 50% probability ellipsoids). Hydrogen atoms have been omitted for clarity.
Table 1
ligands of [MoO2(acac)2] can be removed by protonation with
mildly acidic ligands such as Schiff’s bases to give a wide range
of dioxo molybdenum complexes. Stirring [MoO2(acac)2] with
two equivalents of the thiones 4 for 24 h afforded red-brown pre-
cipitates which were collected by filtration and recrystallised
(Scheme 4). These complexes, 7 and 8, were characterised spectro-
scopically as well as by an X-ray diffraction study of the mesityl
derivative. The solid state IR spectrum of 7 (in KBr) showed two
strong peaks at 946 and 894 cmꢀ1, characteristic of the cis-MoO2
Selected bond lengths (Å) and angles (°) for complex 6.
Ru(1)–C(1)
Ru(1)–P(2)
Ru(1)–S(2)
S(1)–C(2)
S(3)–C(4)
S(4)–C(2)
C(2)–C(3)
1.841(7)
2.3631(16)
2.4585(16)
1.659(6)
1.721(6)
1.730(6)
1.421(8)
Ru(1)–P(1)
Ru(1)–S(1)
Ru(1)–H(1RU)
S(2)–C(3)
S(3)–S(4)
O(1)–C(1)
C(3)–C(4)
2.3500(15)
2.4341(16)
1.5643
1.740(6)
2.054(3)
1.162(7)
1.380(8)
P(1)–Ru(1)–P(2)
O(1)–C(1)–Ru(1)
164.40(5)
177.0(5)
S(1)–Ru(1)–S(2)
84.83(5)
unit; in 8 these appear at lower frequency, 910 and 875 cmꢀ1
.
The 1H NMR spectra displayed only phenyl/mesityl resonances,
but the complexes were not sufficiently soluble to obtain 13C
NMR spectra. The FAB mass spectra of both compounds showed
molecular ion envelopes.
2.2. Molybdenum complexes
Crystallisation of 8 by diffusion of hexane vapour into a CH2Cl2
solution afforded orange-brown crystals of the dichloromethane
solvate suitable for structural investigation. The molecular struc-
ture is shown in Fig. 3 with selected bond lengths and angles col-
lected in Table 2. Due to the unsymmetrical nature of the bidentate
ligand, there are three possible isomers of [MoO2(RC3S4)2] if the
Molybdenum is known to have a high affinity for sulfur and
displays an extensive coordination chemistry with sulfur based
ligands, some of which is of biological importance in the
molybdenum cofactor of oxidoreductase enzymes [8]. We were
therefore prompted to investigate the coordination of the thiones
to molybdenum centres. It is well known that the acetylacetonate
Scheme 4. Synthesis of molybdenum complexes.

176
H. Adams et al. / Inorganica Chimica Acta 363 (2010) 173–178
Fig. 3. Molecular structure of complex 8ꢁCH2Cl2 in the crystal (ORTEP plot, 50% probability ellipsoids). Hydrogen atoms and the dichloromethane of crystallisation have been
omitted for clarity.
Perkin–Elmer 1600 FT-IR machine. The 1H, 13C and 31P NMR spec-
Table 2
Selected bond lengths (Å) and angles (°) for complex 8ꢁCH2Cl2.
tra were obtained in CDCl3 solution on a Bruker AC250 machine
with automated sample-changer or an AMX400 spectrometer.
Chemical shifts are given on the d scale relative to SiMe4 or 85%
H3PO4 = 0.0 ppm. The 13C{1H} NMR spectra were routinely re-
corded using an attached proton test technique (JMOD pulse se-
quence). Mass spectra were recorded on a Fisons/BG Prospec
3000 instrument operating in fast atom bombardment mode with
m-nitrobenzyl alcohol as matrix. Elemental analyses were carried
out by the Microanalytical Service of the Department of Chemistry.
The compounds [Ru(H)(Cl)(CO)(PPh3)3] [12] and [MoO2(acac)2]
[13] were prepared by literature methods.
Mo(1)–O(1)
Mo(1)–S(1)
Mo(1)–S(2)
S(1)–C(2)
1.709(2)
2.4263(8)
2.6838(8)
1.751(3)
1.712(3)
1.720(3)
1.676(3)
2.0457(11)
1.414(4)
1.424(4)
105.19(10)
163.54(7)
165.70(8)
Mo(1)–O(2)
Mo(1)–S(5)
Mo(1)–S(6)
S(2)–C(1)
1.714(2)
2.4417(8)
2.7036(8)
1.689(3)
2.0419(11)
1.751(3)
1.727(3)
1.716(3)
1.375(4)
1.375(4)
154.45(3)
80.61(3)
80.50(2)
S(3)–C(3)
S(3)–S(4)
S(4)–C(1)
S(5)–C(11)
S(6)–C(10)
S(7)–C(10)
S(7)–S(8)
S(8)–C(12)
C(1)–C(2)
C(2)–C(3)
C(10)–C(11)
O(1)–Mo(1)–O(2)
O(1)–Mo(1)–S(2)
O(2)–Mo(1)–S(6)
C(11)–C(12)
S(1)–Mo(1)–S(5)
S(1)–Mo(1)–S(2)
S(5)–Mo(1)–S(6)
3.2. Synthesis of [Ru(H)(PhC3S4)(CO)(PPh3)2] (5)
(i) One pot reaction
two oxo ligands are assumed to retain their cis geometry (as is usu-
ally the case). The methyl region of the 1H NMR spectrum of 8 indi-
cates that only one isomer is formed. In the crystal it is the one in
which the two thiolate sulfurs are trans to each other, and the two
thione sulfurs are trans to the oxo ligands. A similar arrangement
was found in the MoO2 complex of the dianion of 2,3:8,9-diben-
zo-1,4,7,10-tetrathiadecane (ꢀSC6H4SCH2CH2SC6H4Sꢀ); the two
thiolate sulfurs were trans to each other and the two uncharged
thioether sulfur atoms were trans to the oxo ligands [9].
A solution of phenylacetylene (0.29 mL, 2.64 mmol) in THF
(17.9 mL) was cooled to ꢀ78 °C and treated with nBuLi (1.64 mL
of 1.6 M solution, 2.63 mmol). After stirring at room temperature
for 30 min, the solution was re-cooled to ꢀ78 °C and carbon disul-
fide (0.15 mL, 2.5 mmol) was added. The pale yellow solution was
allowed to warm to room temperature and stirred for 1 h, causing a
colour change to dark red. An excess of elemental sulfur (0.26 g,
8.08 mmol of S) was added, causing an instant colour change to
bright red-pink. After stirring for 1 h, 8.75 mL of this solution (i.e.
1.15 mmol of anion) was transferred by syringe to a second
Schlenk tube containing a suspension of [Ru(H)(Cl)(CO)(PPh3)3]
(1.00 g, 1.04 mmol) in THF (20 mL). The resulting blue-turquoise
solution was allowed to stir for 24 h. After the addition of a small
amount of silica, the solution was evaporated to dryness and the
residue loaded onto a chromatography column. Elution with light
petroleum and CH2Cl2 (7:3), afforded a blue-turquoise band of 5
(0.8295 g, 88%).
It is well known that [MoO2(dtc)2], where dtc ¼ Et2NCSꢀ , acts
2
as an oxygen atom transfer reagent towards substrates such as
PPh3 [10]. However attempts to induce a similar reaction by treat-
ing 7 with PPh3, either at room temperature or elevated tempera-
ture, showed no evidence of success.
2.3. Conclusion
Complexes containing the anion of 4-mercapto-1,2,-dithiole-3-
thiones can be prepared in good yield either in situ from terminal
alkynes, or by deprotonation of the heterocycle. Coordination oc-
curs through the two exocyclic sulfur atoms, forming a five-mem-
bered chelate ring.
(ii) From 4-mercapto-5-phenyl-1,2-dithiole-3-thione
An orange solution of the heterocycle (40 mg, 0.18 mmol) in
THF (10 mL) was treated with NEt3 (0.03 mL, 0.18 mmol), causing
a colour change to dark red. The complex [Ru(H)(Cl)(CO)(PPh3)3]
(0.158 g, 0.166 mmol) was added, and the solution stirred for 1 h.
Column chromatography, eluting with light petroleum-dichloro-
methane (7:3), gave 5 (0.1387 g, 93%).
3. Experimental
Data for 5: IR 1930 cmꢀ1 1H NMR: d 7.80–7.10 (m, 35 H, Ph),
.
3.1. General
ꢀ9.54 (t, J = 18.0 Hz, 1 H, Ru–H of major isomer), ꢀ9.86 (t,
J = 17.5 Hz, 1 H, Ru–H of minor isomer). 13C NMR (major isomer):
d 213.1 (s, C@S), 202.2 (t, J = 13 Hz, CO), 163.6 (s, CPh), 151.0 (t,
J = 3 Hz, CS), 134.7-127.2 (m, Ph). 31P NMR: d 43.2 (major isomer),
43.4 (minor isomer). Anal. Calc. for RuC46H36OP2S4: C, 61.68; H,
General experimental techniques were as described in a recent
paper from this laboratory [11]. Infra-red spectra were recorded
either in CH2Cl2 solution (0.5 mm NaCl cells) or as KBr discs on a

H. Adams et al. / Inorganica Chimica Acta 363 (2010) 173–178
177
4.02; S, 14.30. Found: C, 61.94; H, 4.17; S, 14.60%. Mass spectrum:
Mes), 21.3 (s, Me), 21.2 (s, 2Me). Anal. Calc. for RuC49H42OP2S4: C,
62.75; H, 4.48; S, 13.66. Found: C, 62.77; H, 4.56; S, 13.69%. Mass
spectrum: m/z 938 (M+H)+.
m/z 896 (M+H)+.
3.3. Synthesis of [Ru(H)(MesC3S4)(CO)(PPh3)2] (6)
3.4. Synthesis of [MoO2(PhC3S4)2] (7)
(i) One pot reaction
The heterocycle 4a (80 mg, 0.33 mmol), dissolved in THF (2 mL)
was added to a solution of [MoO2(acac)2] (50 mg, 0.17 mmol) in
methanol (10 mL). After stirring for 24 h, the red-brown precipitate
was filtered off, washed with methanol, and recrystallised from
CH2Cl2 and light petroleum. Yield 63.6 mg, 63%.
In the same manner as above, a solution of mesityl acetylene
(0.25 mL, 2.22 mmol) in THF (18.2 mL) was treated sequentially
with nBuLi (1.40 mL of 1.6 M solution, 2.24 mmol), carbon disulfide
(0.15 mL, 2.5 mmol), and sulfur (0.21 g, 6.66 mmol of S). A portion
of this solution (10.41 mL, containing 1.16 mmol of anion) was
Data for 7: IR (KBr): 946s, 894s cmꢀ1(Mo@O). 1H NMR: d 7.65–
7.20 (m, Ph). Anal. Calcd. for C18H10MoO2S8: C, 35.40; H, 1.64; S,
41.97. Found: C, 35.87; H, 1.97; S, 42.55%. Mass spectrum m/z
610 (M+).
then added to
a Schlenk tube containing a suspension of
[Ru(H)(Cl)(CO)(PPh3)3] (1.00 g, 1.04 mmol) in THF (20 mL). This
reaction was stirred for 24 h, producing a blue-black solution. Col-
umn chromatography as above, eluting with light petroleum-
dichloromethane (3:2) afforded
(0.7072 g, 72%).
a dark turquoise band of 6
3.5. Synthesis of [MoO2(MesC3S4)2] (8)
(ii) From 4-mercapto-5-mesityl-1,2-dithiole-3-thione
A solution of heterocycle 4b (100 mg, 0.35 mmol) in THF (2 mL)
was added to [MoO2(acac)2] (60 mg, 0.18 mmol) dissolved in
methanol (10 mL). After stirring for 24 h, the orange-brown precip-
itate was filtered off, washed with methanol, and recrystallised
from CH2Cl2 and light petroleum. Yield 49.6 mg, 43%.
The heterocycle (50 mg, 0.19 mmol) in THF (10 mL) was depro-
tonated with triethylamine (0.03 mL, 0.19 mmol) and [Ru(H)(Cl)
(CO)(PPh3)3] (0.16 g, 0.17 mmol) was added. Stirring for 72 h pro-
duced a turquoise-green solution. Column chromatography as
above, eluting with a 13:7 mixture of light petroleum and CH2Cl2,
gave 6 (0.1414 g, 89%).
Data for 8: IR (KBr) 910s, 875s cmꢀ1. (Mo@O). 1H NMR: d 7.25 (s,
4H, CH), 2.15 (s, 6H, Me), 1.60 (s, 12H, 2Me). Anal. Calcd. for
C24H22MoO2S8: C, 41.50; H, 3.17; S, 36.89. Found: C, 41.58; H,
3.20; S, 37.22%. Mass spectrum m/z 696 (M)+.
Data for 6: IR: 1932 cmꢀ1 1H NMR: Major isomer: d 7.70–7.28
.
(m, 30 H, Ph), 6.70 (s, 2 H of Mes), 2.20 (s, 3 H, Me), 1.75 (s, 6 H,
2Me), ꢀ9.47 (t, J = 19.5 Hz, 1 H, Ru–H). Minor isomer: d 7.70–
7.28 (m, 30 H, Ph), 6.80 (s, 2 H of Mes), 2.27 (s, 3 H, Me), 1.78 (s,
6 H, 2Me), ꢀ10.43 (t, J = 18.5 Hz, 1 H, Ru–H).13C NMR: Major iso-
mer: d 213.3 (s, C@S), 201.3 (t, J = 15 Hz, CO), 165.0 (s, CMes),
150.1 (t, J = 2 Hz, CS), 139.1 (s, CMe), 137.2 (s, 2CMe), 133.0–
127.0 (m, Ph/Mes), 21.2 (s, Me), 19.6 (s, 2Me). Minor isomer: d
216.1 (s, C@S), 204.0 (t, J = 15 Hz, CO), 165.5 (s, CMes), 153.0 (t,
J = 2 Hz, CS), 139.5 (s, CMe), 137.8 (s, 2CMe), 133.0–127.0 (m, Ph/
3.6. Crystal structure determinations
Details of the data collection and refinement are collected in Ta-
ble 3. A Bruker Smart CCD area detector with Oxford Cryosystems
low temperature system was used for data collection. Complex
scattering factors were taken from the program package SHELXTL
as implemented on a Viglen Pentium computer [14]. Hydrogen
atoms were placed geometrically and refined in riding mode with
Uiso constrained to be 1.2 (1.5 for methyl groups) times Ueq of the
carrier atom.
Table 3
Summary of crystallographic data for complexes 6 and 8ꢁCH2Cl2.
6
8ꢁCH2Cl2
Acknowledgements
Empirical formula
Formula weight
T/K
Crystal system
Space group
a (Å)
C49H42OP2RuS4
938.08
150(2)
monoclinic
P21/c
17.854(2)
11.8777(13)
21.597(2)
90
C25H24Cl2MoO2S8
779.76
100(2)
orthorhombic
P212121
8.7520(14)
16.527(3)
21.600(3)
90
We thank the University of Sheffield for support. We also thank
the many undergraduate students who prepared [RuH(Cl)(-
CO)(PPh3)3] as part of their laboratory course.
b (Å)
c (Å)
Appendix A. Supplementary material
a
(°)
CCDC 731884 (8) and 731885 (6) contain the supplementary
crystallographic data for this paper. These data can be obtained
free of charge from The Cambridge Crystallographic Data Centre
via http://www.ccdc.cam.ac.uk/data_request/cif.
Supplementary data associated with this article can be found, in
the online version, at doi:10.1016/j.ica.2009.09.015.
b(°)°
111.263(2)
90
4268.2(8)
4
1.460
0.676
90
90
3124.3(9)
4
1.658
c
(°)
V (Å3)
Z
Density (calcd)(Mgmꢀ3
)
l
(mmꢀ1
)
1.150
1576
F(0 0 0)
1928
0.23 ꢂ 0.12 ꢂ 0.04
Crystal size (mm3)
0.43 ꢂ 0.27 ꢂ 0.27
h range for data collection 1.22–27.60
(°)
1.55–27.56
References
Reflections collected (°)
Independent reflections
Data/restraints/
36 483
9567 [R(int) = 0.1189]
9567/0/514
34 990
7133 [R(int) = 0.0460]
7133/0/349
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parameters
Goodness-of-fit on F2
1.010
1.047
Final R1, wR2 [I > 2
r
(I)]
R1 = 0.0608,
wR2 = 0.1384
R1 = 0.1522,
wR2 = 0.1805
1.448 and ꢀ2.075
R1 = 0.0284,
wR2 = 0.0686
R1 = 0.0311,
wR2 = 0.0698
1.001 and ꢀ0.335
(all data)
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Largest diff. peak and
hole (e Åꢀ3
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