Synthesis and characterization of Co(II) and Mn(II) [M3L3] triangles

Article abstract of DOI:10.1007/s10847-019-00904-y

Abstract: We report an improved method to make the ligand N,N′-(pyrazine-2,5-diylbis(methanylylidene))bis(2-(pyridin-2-yl)ethanamine) (L) and the subsequent complexation of this ligand to make the triangular metallo-macrocycles [Co₃L₃

Full text of DOI:10.1007/s10847-019-00904-y

Journal of Inclusion Phenomena and Macrocyclic Chemistry
https://doi.org/10.1007/s10847-019-00904-y
ORIGINAL ARTICLE
Synthesis and characterization of Co(II) and Mn(II) [M3L3] triangles
Tyson N. Dais1 · Michael J. Brown1 · Martyn P. Coles2 · François Laur3 · Jason R. Price4 · Gareth J. Rowlands1 ·
Paul G. Plieger1
Received: 14 January 2019 / Accepted: 23 March 2019
© Springer Nature B.V. 2019
Abstract
We report an improved method to make the ligand N,N′-(pyrazine-2,5-diylbis(methanylylidene))bis(2-(pyridin-2-yl)ethan-
amine) (L) and the subsequent complexation of this ligand to make the triangular metallo-macrocycles [Co3L3](ClO4)6·2H2O
(C1·2H2O) and [Mn3L3](ClO4)6·3H2O (C2·3H2O). Single crystal X-ray analysis of both trimeric circular helicates reveal the
complexes pack in enantiomeric pairs in close synergy with the accompanying anions.
Graphical abstract
Keywords Cyclohelicates · Cobalt · Manganese · Pyrazine · Metallo-macrocycle
A contribution in celebration of my friend and collaborator
Karsten Gloe on the occasion of his 70th birthday.
3
* Paul G. Plieger
Faculté de Sciences Fondamentales et Appliquées, Université
de Poitiers, TSA 51106, 86073 Poitiers Cedex 9, France
p.g.plieger@massey.ac.nz
4
Australian Synchrotron, 800 Blackburn Road, Clayton,
VIC 3168, Australia
1
School of Fundamental Sciences, Massey University,
Palmerston North 4410, New Zealand
2
School of Chemical and Physical Sciences, Victoria
University of Wellington, PO Box 600, Wellington 6012,
New Zealand
Vol.:(0123456789)
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Journal of Inclusion Phenomena and Macrocyclic Chemistry
strain [3]. Although the formation of cyclohelicate squares
has been reported more frequently, bridging ligands with
increased fexibility have been reported to more easily form
triangles by distributing geometric strain as smaller defor-
mations throughout the ligand backbone [3, 10].
Introduction
The combination of metal ion and ligand allows complexes
to self-assemble into a variety of supramolecular architec-
tures. An interesting structure produced by this strategy is
the class of cyclohelicates with an [MxLx] composition. In
these structures each ligand provides two polydentate chelat-
ing pockets typically in a bis-bidentate or bis-tridentate
fashion, acting as a rigid arm connecting two metal centres
[1–5]. The outcome of the self-assembly process is domi-
nated by the design of the bridging ligand and the often-pre-
dictable coordination geometry of the metal ion [3, 6]. Due
to the wide structural diversity of ligands, and the diferent
metal geometries, it is possible to create cyclohelicates of
various shapes including, but not limited to, triangles [M3L3]
and squares [M4L4], the latter being an example of a chiral
2×2 grid complex (Fig. 1) [4, 6].
Pyrazine-based ligands incorporating hydrazone- and
amide-type bridges to attach ancillary pyridyl groups have
been used extensively in the past to produce M4L4 cycloheli-
cate squares [2, 11, 12]. Previous work by Plieger et al. has
also demonstrated the use of iminopyridyl moieties attached
to a 3,6-disubstituted pyridazine for the binding of octahe-
dral metal centres [13]. This work incorporates imine-type
bridges to produce a pyrazine-based bis-tridentate ligand
with two antiparallel N3 binding environments, which were
found to form isomorphic M3L3 cyclohelicate triangles with
manganese and cobalt.
Ligands composed of two antiparallel bi- or tridentate
chelating arms should be designed such that they match the
typical binding geometry of the metal [1, 2]. Cyclohelicates
containing octahedrally coordinated metal centres are more
commonly explored as they have displayed more exotic
electrochemical properties, while tetrahedrally coordinated
metal centres tend to alter their coordination geometry upon
redox processes and are thus less studied [7]. The formation
of cyclohelicates can be understood by looking at the direc-
tional bonding approach and the molecular library model [8,
9]. The self-assembly of octahedral metal centres with rigid
linear bridging ligands is expected to produce a square archi-
tecture, however the formation of triangles has been reported
[3, 5, 10]. As both square and triangular cyclohelicates can
be synthesised under identical conditions, both entropic and
enthalpic factors determine which structures will be formed.
Entropy favours the formation of the cyclohelicate trian-
gles as more discrete molecules will be formed compared
to the cyclohelicate square, however, cyclohelicate squares
are more enthalpically favoured due to a lower geometric
Results and discussion
Synthesis
A simple 3-step approach (see Scheme 1) has been
employed in the synthesis of N,N′-(pyrazine-2,5-
diylbis(methanylylidene))bis(2-(pyridin-2-yl)ethanamine)
(L). 2,5-distyrylpyrazine (2) was synthesized in high purity
and good yield by a microwave-mediated condensation
based on a report by Coufal et al. [14]. The distyryl deriva-
tive was sufciently pure to use directly in the subsequent
ozonolysis to give the aldehyde building block (3) [15]. Fol-
lowing work-up, the ozonolysis product (3) was obtained in
sufcient purity, as evidenced by NMR and MS, to be used
Fig. 1 An M4L4 cyclohelicate (a) and an M3L3 cyclohelicate (b)
where blue cylinders represent ligands and red spheres represent
metal centres
Scheme 1 Synthesis of the bis-tridentate ligand L
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Journal of Inclusion Phenomena and Macrocyclic Chemistry
those reported by Brooker et al. [15]. Improved data suf-
fcient to identify the heavily disordered anions was subse-
quently obtained from the Australian synchrotron facility.
The CHN elemental analyses indicate the presence of six
and eight non-coordinated water molecules in C1 and C2,
respectively. Samples of each complex were crushed and
analyzed by thermogravimetric analysis (TGA) to further
confrm the presence of these water molecules. A 5.6% loss
in mass was observed for C1 over 4 h, corresponding to
the loss of 6 water molecules. C2 was observed to decrease
in mass by 7.2% over 2.5 h, corresponding to the loss of
almost 8 water molecules, followed by an energetic event
causing an instantaneous 8% decrease in total mass indicat-
ing sample removal of the thermobalance. These results are
consistent with the presence of water observed in the X-ray
crystal structure determinations. Conductivity studies indi-
cated both C1 and C2 have high electrolyte cation to anion
ratios, however, due to the low mobility in solution and low
solubilities of the complexes no reliable conclusions about
exact electrolyte ratios can be drawn.
Fig. 2 X-ray structure of the ligand L
in the fnal reaction without further purifcation. Previously,
complexations were performed as a one-pot reaction with
the Schif base condensation, however we favour the isola-
tion and characterization of the Schif base ligand (L) prior
to complexation (Fig. 2).
By adopting a microwave based synthesis of the distyryl
derivative (2), a reduction in the reaction time to 6 h was
achieved with higher purity than that previously reported.
The total synthesis was completed in 3 days with an over-
all yield of 62%. This compares favourably to previously
reported methods with, for example the 3 day reaction of
Brooker et al. providing L in 54% yield [3]. Our method also
provided a more accessible 2-step synthesis of the dicar-
baldehyde derivative (3) from 2,5-dimethylpyrazine (1).
White needle-like single crystals of the Schif base ligand
(L) suitable for X-ray structural analysis were obtained by
hot recrystallization from acetonitrile and confrmed the suc-
cessful synthesis. The ligand crystalizes in the P21/c space
group, thus the full ligand structure (Fig. 2) was generated
through an inversion centre in the middle of the pyrazine
ring. The imine groups adopted an E-conformation and sit
in the plane of the pyrazine ring, with the terminal pyridyl
groups sitting approximately parallel but displaced above
and below the central pyrazine ring.
Each complex is isomorphic with each other and with
the previously reported [Zn3L3](BF4)6 of Brooker et al. [3].
The asymmetric unit contains a ML fragment which com-
prises one-third of the complex, and two perchlorate anions
disordered over fve sites. Applying the symmetry operation
(3-fold rotation through the centre of the triangle of the com-
̄
plex for R3c) perpendicular to the M3 plane, results in the
generation of the full triangular metallo-macrocycle (Fig. 3).
Each octahedral coordinated metal cation shares an N3
donor set from two diferent ligands comprising pyrazine,
imine and pyridine donor nitrogen atoms. The bond lengths
for the metals are consistent with the (+2) oxidation state for
The complexes [Co3L3](ClO4)6 (CI) and [Mn3L3]
(ClO4)6 (C2) were synthesised by reacting the preformed
ligand, N,N′-(pyrazine-2,5-diylbis(methanylylidene))bis(2-
(pyridin-2-yl) ethanamine), (L), with that of the appropriate
metal perchlorate salt in acetonitrile. (Caution: perchlorate
salts are potentially explosive and should be handled with
appropriate care.) Upon reduction of volume, crystals were
observed to form directly from the reaction mixture. These
could be further purifed by fltering, dissolving in acetoni-
trile and subsequently difusing diethyl ether into the solu-
tion containing the respective complex resulted in orange
crystals for the Co(II) complex, and dark red crystals for the
Mn(II) complex. Initial single crystal X-ray studies on our
in-house system provided connectivity and confrmed that
the structures were triangular cyclohelicates, analogous to
Fig. 3 X-ray structure of the cation [Mn3L3]6+
1 3

Journal of Inclusion Phenomena and Macrocyclic Chemistry
each cation. Selected bond distances and angles are shown
in Table 1.
one shared perchlorate anion between them. The remaining
perchlorate anions are distributed in the naturally occurring
voids this structure provides. One fully occupied perchlorate
sits above, but skewed towards one of the nitrogen donors on
the pyrazine ring on each face of the metallo-macrocyclic
triangle. It also sits in close proximity to one of the two
terminal pyridine rings. The remaining 1.5 perchlorates are
distributed evenly around the outer face of the triangle (0.5
occupancy per side) again sitting above and now towards the
other pyrazine nitrogen donor. These again interact weakly
with the other terminal pyridine ring on each side of the
triangle (Fig. 5).
Overall, the structure of each metallo-macrocycle is chi-
̄
ral, with both enantiomers contained within the R3c crystal
symmetry.
The improved quality of the refection data for both of
these structures allowed the positions of the anions to be
clearly identifed. Each enantiomeric cation is balanced by
six perchlorate anions. One ClO4− lies on the six-fold centre
of symmetry with one Cl–O bond aligned with the three-
fold rotation axis in the centre of the triangle. It is therefore
‘pointing’ towards one enantiomer half the time and towards
the other enantiomer the other half of the time (Fig. 4).
A second perchlorate anion occupies the mirror position
on the other side of each enantiomer, again with a Cl–O
bond aligned along the three-fold rotation axis. As such,
the packing can be considered as pairs of enantiomers with
As all examples to date have utilised similar sized anions
−
(BF4− vs. ClO4 ) in the structural determinations, it remains
to be seen whether a diference in incorporated anion will
have any infuence on the overall structure of these triangular
metallo-macrocycles.
Table 1 Selected bond lengths and angles for the C1·2H2O and C2·3H2O
C1·2H2O
C2·3H2O
Bond lengths
Å
Bond lengths
Å
Co–N11pyz
Co–N2pyz
Co–N4imine
Co–N0AA1imine
Co–N6pyrid
Co–N5B1pyrid
Co–N51pyrid
2.200 (3)
2.216 (3)
2.162 (3)
2.142 (3)
2.133 (3)
2.08 (2)
Mn–N11pyz
Mn–N2pyz
Mn–N4imine
Mn–N0AA1imine
Mn–N6pyrid
Mn–N5B1pyrid
Mn–N51pyrid
2.343 (2)
2.341 (2)
2.217 (2)
2.218 (2)
2.203 (2)
2.11 (2)
2.207 (3)
2.267 (18)
Bond angles
Angle/º
Bond angles
Angle/º
N11–Co–N2
81.64 (10)
159.1 (5)
76.07 (11)
90.19 (12)
163.68 (12)
83.5 (4)
86.30 (11)
159.81 (11)
102.59 (12)
88.73 (12)
102.6 (7)
93.20 (12)
75.92 (12)
105.7 (4)
168.1 (5)
92.9 (7)
N11–Mn–N2
81.04 (6)
157.00 (6)
71.96 (6)
87.16 (6)
155.51(7)
85.2 (5)
84.77 (6)
155.79 (6)
106.97 (7)
87.69 (7)
104.7 (6)
90.51 (7)
72.99 (7)
110.4 (5)
163.4 (5)
96.6 (8)
N11–Co–N51
N0AA1–Co–N11
N0AA1–Co–N2
N0AA1–Co–N4
N0AA1–Co–N51
N6–Co–N11
N11–Mn–N51
N0AA1–Mn–N11
N0AA1–Mn–N2
N0AA1–Mn–N4
N0AA1–Mn–N51
N6–Mn–N11
N6–Co–N2
N6–Mn–N2
N6–Co–N0AA1
N6–Co–N4
N6–Mn–N0AA1
N6–Mn–N4
N6–Co–N51
N6–Mn–N51
N4–Co–N11
N4–Mn–N11
N4–Co–N2
N4–Mn–N2
N4–Co–N51
N4–Mn–N51
N5B1–Co–N11
N5B1–Co–N2
N5B1–Co–N0AA1
N5B1–Co–N6
N5B1–Co–N4
N51–Co–N2
N5B1–Mn–N11
N5B1–Mn–N2
N5B1–Mn–N0AA1
N5B1–Mn–N6
N5B1–Mn–N4
N51–Mn–N2
93.5 (4)
101.7 (7)
95.7 (4)
91.5 (5)
102.4 (7)
104.6 (6)
95.8 (6)
94.3 (7)
11−Y,+X−Y,+Z
1 3

Journal of Inclusion Phenomena and Macrocyclic Chemistry
Materials and analysis
All reagents were obtained from commercial sources and
used without further purifcation. Commercially sourced
HPLC grade acetonitrile and methanol was dried over acti-
vated 3 Å molecular sieves for at least 1 week prior to use.
Microwave synthesis was performed using a CEM Discov-
ery Monomode Explorer operating at 100 Watts. Ozonol-
ysis was performed using a CD10/AD Corona Discharge
Ozone Generator. The synthesized ligand and precursors
were characterized by 1H and 13C NMR spectroscopy (solu-
tions in DMSO-d6 or CDCl3, at room temperature) using a
Bruker Avance 500 MHz spectrometer. Melting points were
recorded on a Gallenkamp melting point apparatus, and are
uncorrected. High resolution mass spectrometry was per-
formed using a ThermoScientifc Q Exactive Focus Hybrid
Quadrupole-Orbitrap Mass Spectrometer. Thermogravimet-
ric analysis (TGA) was performed on a Q50 TGA appara-
tus. The Campbell Microanalytical Laboratory, University
of Otago, provided CHN elemental analysis. UV–Vis spectra
were collected on a Shimadzu UV-3101PC spectrophotom-
eter. Conductivity measurements were performed with a
Philips PW9509 conductivity meter.
Fig. 4 A pair of enantiomeric helicates showing the centrally shared
perchlorate positionally disordered over two sites
Synthesis of 2,5‑distyrylpyrazine (2)
2,5-Dimethylpyrazine (0.99 g, 9.15 mmol), benzaldehyde
(4.00 mL, 39.4 mmol) and benzoic anhydride (4.97 g,
22.0 mmol) were stirred in a microwave tube until full dis-
solution occurred. Argon was bubbled through the yellow
mixture and was reacted at 175 °C in the microwave for 5 h,
with rapid stirring. After cooling, a dark brown solid was
obtained, which was suspended in cold ethanol before flter-
ing and washing with cold ethanol to yield a yellow crystal-
line solid (1.61 g, 5.7 mmol, 62%). This product was carried
through to the next reaction without further purifcation. 1H
NMR (500 MHz, CDCl3): δ 8.60 (2H, s, ArH), 7.74 (2H, d,
J=16 Hz, CH), 7.63–7.59 (4H, m, ArH), 7.43–7.31 (6H, m,
ArH), 7.19 (2H, d, J=16 Hz, CH).
Fig. 5 Space flling enantiomeric pair showing the fanking perchlo-
rates sitting on the outside face of the trimeric helicates
Conclusion
Synthesis of pyrazine‑2,5‑dicarbaldehyde (3)
There are now four crystallographic examples of this ligand
with difering octahedral coordination capable transition
metals and in every case the metallo-macrocycle generated
is one of a M3L3 variation as opposed to other stoichio-
metries, for example that of the analogous diamide ligand
[15]. Based on the available evidence it is clearly a ligand-
based phenomena due primarily to the fexibility that this
particular ligand possesses. A study on whether a change in
the incorporated anion would infuence structure is nonethe-
less worthwhile and both this and electrochemical investiga-
tions are on-going.
The dicarbaldehyde derivative was prepared as previously
reported by Brooker et al. [15]. 1H NMR data corresponds
to literature values.
Synthesis of N,N′‑(pyrazine‑2,5‑diylbis(methanylyli
dene))bis(2‑(pyridin‑2‑yl)ethanamine) (L)
2-(2-Aminoethyl)pyridine (1.02 g, 3.0 mmol) was added to
a stirred solution of pyrazine-2,5-dicarbaldehyde (0.52 g,
1.5 mmol) in 10 mL acetonitrile. The mixture was stirred at
1 3

Journal of Inclusion Phenomena and Macrocyclic Chemistry
room temperature for 30 min then left to stand in a freezer
at −5 °C for 3 h. The precipitated solid was fltered and
washed with cold acetonitrile to yield L as a white crystal-
line solid (0.32 g, 0.9 mmol, 62%). Recrystallization from hot
acetonitrile yielded white crystals of X-ray quality. 1H NMR
(500 MHz, DMSO-d6): δ 9.14 (2 H, s, HC=N), 8.55 (2 H, d,
J=4.10 Hz, pyH), 8.35 (2 H, t, J=1.27 Hz, pzH), 7.58 (2 H,
td, J=1.57, 7.6 Hz, pyH), 7.18 (2 H, d, J=7.87 Hz, pyH), 7.12
(2 H, ddd, J=0.99, 4.94, 7.44 Hz, pyH), 4.13 (4 H, dt, J=7.26,
1.26 Hz, CH2), 3.24 (4 H, t, J=7.1 Hz, CH2). MS: m/z=345
(M+, 100%). UV/Vis λmax(MeCN) 257 nm (21000 L mol−1
cm−1), 291 nm (22019 L mol−1 cm−1). MP 138 °C (Sample
decomposed at this temperature).
(w), 1437 (m), 1379 (w), 1348 (w), 1327 (w), 1121 (s), 1086
(s), 1035 (s).
[Co3L3](ClO4)6 (C1): 1631 (w), 1608 (m), 1571 (w),
1484 (w), 1446 (m), 1402 (w), 1363 (w), 1317 (m), 1307
(m), 1251 (w), 1191 (m), 1165 (w), 1019 (m), 985 (w), 952
(m), 882 (w), 864 (w), 840 (w), 831 (w), 825 (w), 813 (w),
784 (w), 768 (m), 755 (m), 741 (m), 724 (m), 717 (m), 699
(w), 684 (w).
[Mn3L3](ClO4)6 (C2): 1641 (w), 1608 (m), 1486 (w),
1443 (m), 1403 (w), 1311 (m), 1183 (m), 1017 (m), 959
(m), 844 (m), 768 (m).
X‑ray crystallography
Synthesis of [Co3L3](ClO4)6·6H2O (C1·6H2O)
Single crystal difraction data for ligand L was collected
at 120 K on an Agilent SuperNova difractometer (using
focused microsource Cu Kα radiation, λ = 1.54184 Å)
with an EOS S2 detector. The structures were solved by
direct methods SHELXS and refned using the SHELXL
as implemented in the Olex2 software package [16–18].
Absorption data scaling corrections were carried out using
multiscan. Hydrogens were calculated at their ideal posi-
tions unless otherwise stated. Single crystal difraction
data for complexes C1 and C2 was collected at 110 K on
the MX2 beamline (λ = 0.7093 Å) at the Australian Syn-
chrotron, Victoria, Australia. The dataset was processed
and evaluated using XDS [19]. The resulting refections
were scaled using AIMLESS140 from the CCP4 program
suite [20]. The structures were solved by direct methods
SHELXS and refned using the SHELXL as implemented
in the Olex2 software package [16–18]. Absorption data
scaling corrections were carried out using multiscan. All
non-H atoms were refned with anisotropic thermal param-
eters. All H atoms were inserted at calculated positions
and rode on the C atoms to which they were attached.
TwinRotMat indicated the presence of a non-merohedral
twin law (− 1 0 0, 0 − 1 0, 0.666 0 1) which was duly
applied to the data for L, resulting in 2% improvement in
R1, BASF=10.8%. Positional disorder was present in both
complexes. In both cases, one of the pyridine arms is posi-
tional disordered in a 50:50 ratio. In addition, one of the
perchlorate anions is rotational disordered in a 45:55 ratio
(C1), and 47:53 (C2). In both structures, one of the cavi-
ties is shared by one perchlorate anion 50% of the time and
residue water solvent over two (C1) and four (C2) sites.
Remaining difuse solvent in C1 and C2 was treated with
SQUEEZE [21] as implemented in the Olex2 software
package. A total of 674 and 873 electrons were removed
per unit volume (or 56 and 73 electrons per asymmetric
unit) for the complexes C1 and C2 respectively. These
approximated to 1.333 molecules of water and two mol-
ecules of CH3CN per asymmetric unit for C1 with Z = 12
A solution of Co(ClO4)2·6H2O (0.14 g, 0.39 mmol) in 3 mL
acetonitrile was added to a solution of L (0.13 g, 0.39 mmol)
in 30 mL acetonitrile producing a orange solution. The mix-
ture was stirred for 30 min then concentrated in vacuo to give
orange crystals. Vapour difusion of diethyl ether into a con-
centrated solution of [Co3L](ClO4)6 in acetonitrile yielded
more orange crystalline material. The product was fltered
then recrystallized by vapour difusion of diethyl ether into a
concentrated solution of [Co3L3](ClO4)6 in acetonitrile to yield
orange crystals of X-ray quality (0.10 g, 0.13 mmol, 39%).
Elemental analysis calcd for [Co3L3](ClO4)6·6H2O: C 37.63,
H 3.79, N 13.17%. Found: C 37.69, H 3.34, N 13.02%. UV/Vis
λmax(MeCN) 240 nm (50195 L mol−1 cm−1), 326 nm (33512
L mol−1 cm−1), 406 nm (8305 L mol−1 cm−1). Conductivity
of [Co3L3](ClO4)6 in CH3CN=0.416 mS cm−1, 419.01 S cm2
mol−1.
Synthesis of [Mn3L3](ClO4)6·8H2O (C2·8H2O)
A solution of Mn(ClO4)2·6H2O (0.13 g, 0.35 mmol) in 10 mL
acetonitrile was added to a solution of L (0.12 g, 0.35 mmol)
in 20 mL acetonitrile producing a dark red coloured solution.
The mixture was stirred for 30 min then concentrated in vacuo.
Vapour difusion of diethyl ether into a concentrated solution
of [Mn3L3](ClO4)6 in acetonitrile yielded dark red crystals of
X-ray quality (0.03 g, 0.12 mmol, 15%). Elemental analysis
calcd for [Mn3L3](ClO4)6·8H2O: C 37.17, H 3.95, N 13.00%.
Found: C 37.59, H 3.58, N 13.25%. UV/Vis λmax(MeCN)
248 nm (41565 L mol−1 cm−1), 306 nm (38730 L mol−1 cm−1),
400 nm (weakly absorbing shoulder). Conductivity of [Mn3L3]
(ClO4)6 in CH3CN=0.320 mS cm−1, 554.76 S cm−2 mol−1.
The characteristic FTIR bands (cm−1) of ligand L
and complexes C1 and C2
N,N′-(pyrazine-2,5-diylbis(methanylylidene))bis(2-(pyridin-
2-yl)ethanamine) (L): 1642 (m), 1590 (m), 1571 (m), 1477
1 3

Journal of Inclusion Phenomena and Macrocyclic Chemistry
Table 2 Crystallographic data and structure refnement details for all compounds
L
C1
C2
CCDC number
Empirical formula
Formula weight
T/K
Crystal system
Space group
a/Å
1890125
C20H20N6
344.42
120(1)
monoclinic
P21/c
6.0968(2)
4.60769(17)
31.7665(12)
93.622(3)
90
890.61(6)
2
1890162
C60H60Cl6Co3N18O26
1838.76
100(2)
trigonal
̄
R3c
1890780
C60H66Cl6Mn3N18O27
1848.82
100(2)
trigonal
̄
R3c
25.397(4)
25.397(4)
45.748(9)
90
120
25554(9)
12
25.397(4)
25.397(4)
45.748(9)
90
120
25554(9)
12
b/Å
c/Å
β/°
γ/°
Volume/Å3
Z
ρcalcg/cm3
1.284
0.640
1.434
0.846
1.442
0.709
μ/mm−1
F(000)
364
11244
11340
Crystal size/mm3
Radiation
0.149×0.136×0.046
Cu Kα (λ=1.54184)
0.02×0.005×0.003
Mo Kα (λ=0.71073)
4.98 to 52.598
0.15×0.12×0.1
Mo Kα (λ=0.71073)
2.568 to 56.61
2Θ range for data collection/° 8.366 to 145.99
Index ranges
−4≤h≤7, −5≤k≤5, −39≤l≤39 −31≤h≤31, −31≤k≤31,
−33≤h≤33, −33≤k≤33,
−55≤l≤55
−60≤l≤60
Refections collected
4850
54503
131410
Independent refections
Data/restraints/parameters
Goodness-of-ft on F2
1708 [Rint =0.0284, Rsigma =0.0288] 5627 [Rint =0.0694, Rsigma =0.0381] 7067 [Rint =0.0720, Rsigma =0.0236]
1708/0/119
1.156
5627/268/481
1.049
7067/312/509
1.039
Final R indexes [I≥2σ (I)]
Final R indexes [all data]
R1 =0.0790, wR2 =0.2307
R1 =0.0838, wR2 =0.2385
R1 =0.0660, wR2 =0.2040
R1 =0.0765, wR2 =0.2177
0.86/−0.42
R1 =0.0535, wR2 =0.1614
R1 =0.0559, wR2 =0.1640
0.74/−0.76
Largest dif. peak/hole/e Å−3 0.40/−0.28
5. Zhang, L., August, D.P., Zhong, J., Whitehead, G.F.S., Vitorica-
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(~ 57 e−) and three molecules of water and two molecules
of CH3CN per asymmetric unit for C2 with Z = 12 (~ 74
e−). The crystallographic data are summarised in Table 2.
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