A novel octacyanido dicobalt(iii) building block for the construction of heterometallic compounds

Article abstract of DOI:10.1039/c9nj00420c

The first bimetallic octacyanido complex of Co^III, (PPh₄)₂[Co₂(μ-2,5-dpp)(CN)₈] (1), was synthesized and used as a metalloligand with [Mn(MAC)(H₂O)₂]Cl₂·4H₂

Full text of DOI:10.1039/c9nj00420c

View Article Online
View Journal
NJC
Accepted Manuscript
This article can be cited before page numbers have been issued, to do this please use: M. Alexandru, N.
Marino, D. Visinescu, G. De Munno, M. Andruh, A. Bentama, F. Lloret and M. Julve, New J. Chem., 2019,
DOI: 10.1039/C9NJ00420C.
This is an Accepted Manuscript, which has been through the
Volume 40 Number
1 January 2016 Pages 1–846
Royal Society of Chemistry peer review process and has been
accepted for publication.
NJC
Accepted Manuscripts are published online shortly after
New Journal of Chemistry
www.rsc.org/njc
A journal for new directions in chemistry
acceptance, before technical editing, formatting and proof reading.
Using this free service, authors can make their results available
to the community, in citable form, before we publish the edited
article. We will replace this Accepted Manuscript with the edited
and formatted Advance Article as soon as it is available.
You can find more information about Accepted Manuscripts in the
author guidelines.
Please note that technical editing may introduce minor changes
to the text and/or graphics, which may alter content. The journal’s
standard Terms & Conditions and the ethical guidelines, outlined
in our author and reviewer resource centre, still apply. In no
event shall the Royal Society of Chemistry be held responsible
for any errors or omissions in this Accepted Manuscript or any
consequences arising from the use of any information it contains.
ISSN 1144-0546
PAPER
Jason B. Benedict et al.
The role of atropisomers on the photo-reactivity and fatigue of
diarylethene-based metal–organic frameworks
rsc.li/njc

Please do not adjust margins
Page 1 of 9
New Journal of Chemistry
1
2
3
4
5
6
7
View Article Online
DOI: 10.1039/C9NJ00420C
ARTICLE
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
A novel octacyanido dicobalt(III) building block for the
construction of heterometallic compounds
Maria-Gabriela Alexandru,*a Nadia Marino,*b Diana Visinescu,c Giovanni De Munno,b
Received 00th January 20xx,
Accepted 00th January 20xx
Marius Andruh,d Abdeslem Bentama,e Francesc Lloret,f and Miguel Julve*f
DOI: 10.1039/x0xx00000x
The first bimetallic octacyanido complex of CoIII, (PPh4)2[Co2(μ-2,5-dpp)(CN)8], (1), was synthesized and used as a
metalloligand towards [Mn(MAC)(H2O)2]Cl2·4H2O to give a new {CoIIIMnII} heterometallic chain of formula [MnII(MAC)(μ-
+
NC)2Co2III(μ-2,5-dpp)(CN)6]n·7nH2O (2) (PPh4 = tetraphenylphosphonium cation; 2,5-dpp = 2,5-bis(2-pyridyl)pyrazine and
MAC = 2,13-dimethyl-3,6,9,12,18-pentaazabicyclo-[12.3.1]octadeca-1(18),2,12,14,16-pentaene). Both compounds were
characterized by single-crystal X-ray diffraction. Compound 1 contains a diamagnetic 2,5-dpp-bridged dicobalt(III) unit with
four peripheral cyanide ligands at each cobalt center achieving a six-coordinate surrounding, the electroneutrality being
ensured by bulky tetraphenylphosphonium cations. The structure of 2 consists of neutral heterobimetallic chains where the
[Co2(μ-2,5-dpp)(CN)8]2- complex anion adopts a bis-monodentate bridging mode towards the [Mn(MAC)]2+ cation. Each
manganese(II) ion in 2 is seven-coordinate with five quasi coplanar nitrogen atoms from the macrocycle and two trans-
positioned cyanide-nitrogen atoms building a somewhat distorted pentagonal bipyramidal environment. Cryomagnetic
measurements for 2 reveal the occurrence of quasi magnetically isolated spin sextets in the temperature range 1.9-300 K.
Introduction
towards transition metal ions. Examples of complexes with the
2,5-dpp molecule are still scarce, most likely because of the
Polypyridyl-type ligands have been used as spacers towards
transition metal ions to form polynuclear complexes with
interesting structures and properties.1 Exhaustive studies were
performed on complexes of RuII, OsII, IrIII or PtII with
pyridylpyrazine-type ligands focusing on their rich
electrochemical and photophysical properties.1d,e,f,i Some of
these polydentate ligands induce spin crossover (SCO)
phenomena in their FeII complexes.1g Other examples with RuII,
RhIII, IrIII and AuIII exhibit (photo)cytotoxic activity.1b,h,i A special
attention was also devoted to organometallic compounds of IrIII,
RuII, AgI, ReI, PtII , etc.1j
difficult synthetic route for this ligand.2 In this respect, it
deserves to be noted that the synthetic method used by Escuer
et al. (first five steps in Scheme 1; yield 10%)2a was improved by
some of us (last step in Scheme 1; yield ca. 50%).2b Recently, an
alternative procedure to obtain this molecule published which
is carried out under harder conditions (e.g. temperature of -78
oC) affords practically the same yield (ca. 55%).2c
The organic compound 2,5-bis(2-pyridyl)pyrazine (2,5-dpp)
represents an advantageous option as a ligand aiming at
obtaining coordination compounds since it can act as a linker
a. Department of Inorganic Chemistry, Physical Chemistry and Electrochemistry,
Faculty of Applied Chemistry and Materials Science, University Politehnica of
Bucharest, 1-7 Gh, Polizu Street, 011061 Bucharest, Romania. E-mail:
alexandru.gabriela@gmail.com
Scheme 1. Preparative route of 2,5-dpp.
b. Dipartimento di Chimica e Tecnologie Chimiche, Università della Calabria, 87036
Rende, Cosenza, Italy. E-mail: nadia.marino@unical.it
Mononuclear complexes with 2,5-dpp were prepared and
characterized especially with heavy metal ions such as RuIII, OsIII,
CdII.3 A tweezer molecule of PtII with 2,5-dpp, able to form
heterobimetallic complexes was reported,4 as well as
heteroleptic RuII polynuclear complexes5 and emissive IrIII
complexes.2c There are also several examples of 2,5-dpp
c. c
Coordination and Supramolecular Chemistry Laboratory, “Ilie Murglescu”
Institute of Physical Chemistry, Romanian Academy, Spaiul Independentei 202,
Bucharest 060021, Romania
d. Inorganic Chemistry Laboratory, Faculty of Chemistry, University of Bucharest, Str.
Dumbrava Rosie nr. 23, 020464, Bucharest, Romania.
e. Laboratoire de Chimie Organique Appliquée, Faculté des Sciences Techniques de
Fès, Université Sidi Mohammed Ben Abdellah, Fès, Morocco
f. Departament de Química Inorgànica/Instituto de Ciencia Molecular (ICMol),
Universitat de València, C/ Catedrático José Beltrán 2, 46990 Paterna, Valencia, bridged hetero- and homometallic complexes are known. The
Spain. E-mail: miguel.julve@uv.es.
photoluminescent {CuIRuII} heterometallic species of formula
[(bpy)2RuII(μ-2,5-dpp)CuI(PPh3)2](PF6)5 is one example of the
former ones.6 A series of binuclear complexes of divalent 3d
† Electronic Supplementary Information (ESI) available: Infrared spectra [Figs. S1 (1)
and S2 (2)] and tables of bond lengths and angles [Tabs. S1 (1) and S2 (2)]. CCDC
1892383 and1892384 for complexes
DOI: 10.1039/x0xx00000x
1
and 2, respectively. See
Please do not adjust margins

Please do not adjust margins
New Journal of Chemistry
Page 2 of 9
ARTICLE
Journal Name
1
2
3
4
5
6
7
8
9
metal ions which were reported by Escuer2a and Soeckli-Evans7 Synthesis of (PPh4)2[Co2(μ-2,5-dpp)(CN)8]·2H2O (1)
View Article Online
DOI: 10.1039/C9NJ00420C
are illustrative examples of the second ones. The ability of the
2.5-dpp ligand to mediate weak magnetic interactions between
CuII ions when adopting a bis-bidentate coordination mode has
been investigated by some of us.2b,8
A methanolic solution (20 mL) of 2,5-dpp (0.292 g, 1.25 mmol)
was poured into an aqueous solutions (20 mL) of Co(NO3)2·6H2O
(0.595 g, 2.5 mmol) under continuous stirring for 10 minutes, to
form an orange solution. Then, an aqueous solution (10 mL) of
KCN (0.528 g, 8 mmol) was added dropwise under stirring. The
green suspension initially formed turned into a clear yellow
solution in a few minutes. The addition of solid Ph4PCl (0.748 g,
2.5 mmol) caused the precipitation of complex 1 as a yellow
polycrystalline solid. It was collected by filtration and its
recrystallization from a H2O:CH3OH (1:10 v/v) solvent mixture in
a hood afforded X-ray quality crystals of 1 as pale yellow blocks.
Yield: ca. 55%. Anal. calc. for C70H54Co2N12O2P2 (1): C, 65.94; H,
4.27; N, 13.18. Found: C, 66.08; H, 4.96; N 13.04%. IR (KBr/cm-
1): 3432(vs), 2922(m), 2130(s), 1624(m), 1585(m), 1438(s),
1109(s), 786(m), 759(s), 690(m), 528(s).
A series of mononuclear heteroleptic cyanide complexes of
general formula XPh4[MIII(AA)(CN)4] [M = Cr, Fe and Co; X = P
and As; AA = bidentate ligand] have been used as metalloligands
for metal assembling affording nD (n = 0-3) heterometallic
compounds with interesting magnetic properties.9-12 The
rational design of cyanide-bridged FeIII-CoII ribbon-like motifs
with slow relaxation of the magnetization (referred to as Single
Chain Magnets) being one of most appealing results obtained
through this strategy.11a-c,13 The preparation of dinuclear
cyanide-bearing precursors with a bis-bidentate ligands instead
of the bidentate AA would open new avenues towards novel
heterometallic species. This strategy was nicely illustrated by
Herrera et al. in a report where the authors prepared the 3D
lattice by using the [{RuII(CN)4}2(μ-bpym)]4- precursor (bpym =
2,2’-bipyrimidine) as metalloligand towards [GdIII(hfac)3(H2O)2]
(Hhfac = hexafluoroacetylacetone).14
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Synthesis of [MnII(MAC)(μ-NC)2Co2III(μ-2,5-dpp)(CN)6]n·7nH2O
(2)
A solution of 127 mg 1 dissolved in 15 mL of a methanol:water
(5:1 v/v) solvent mixture was introduced in a test tube. Then, a
methanolic solution (10 mL) of [Mn(MAC)(H2O)2]Cl2·4H2O (51
mg, 0.1 mmol) was layered over it and the tube was covered
with parafilm. X-ray quality crystals of 1 were obtained after
three weeks under ambient conditions. Yield: ca. 60%. Anal.
calcd. for C37H47Co2N17MnO7 (2): C, 43.80; H, 4.67; N, 23.47.
Found: C, 43.19; H, 4.16; N, 23.14%. IR (KBr/cm-1): 3463(m),
2924(w), 2139(s), 1649(s), 1441(s), 1198(m), 787(m).
Having this in mind, and taking advantage of the potential
bis-bidentate character of the 2,5-dpp molecule, we prepared
the first dinuclear 3d-cyanide building block with 2,5-dpp of
+
formula (PPh4)2[CoIII (μ-2,5-dpp)(CN)8]·2H2O (1) (PPh4
=
2
tetraphenylphosphonium cation) and used it as a metalloligand
towards to afford the
[MnII(MAC)(H2O)2]·4H2O15,16
polymer
[MnII(MAC)(μ-
heterobimetallic
NC)2Co2 (μ-2,5-dpp)(CN)6]n·7nH2O (2), [MAC = 2,13-dimethyl-
3,6,9,12,18-pentaazabicyclo-[12.3.1]octadeca-
coordination
III
Physical measurements
1(18),2,12,14,16-pentaene] (see Scheme 2). Herein we report
the preparation and X-ray structures of 1 and 2 together with
the cryomagnetic study of 2.
Elemental analyses (C, H, N) were performed by the Servicio
de Microanálisis from the Universidad Autónoma de Madrid.
The values of the Co:P (1) and Co:Mn (2) molar ratios (1:1 and
2:1, respectively) were determined by electron microscopy at
the Servicio Interdepartamental de la Universidad de Valencia.
FTIR spectra (4000-300 cm-1) were recorded on a Bruker FS55
spectrophotometer on samples of 1 and 2 prepared as KBr
pellets. Variable-temperature (1.9-300 K) magnetic
susceptibility measurements on a polycrystalline sample of 2
were carried out with a SQUID susceptometer using applied
magnetic fields of 1 T (T ≤ 50 K) and 500 G (T < 50 K).
Magnetization versus magnetic field measurements of 2 were
performed at 2.0 K in the field range 0-5 T. Diamagnetic
corrections for the constituent atoms were made by using the
Pascal’s constants. The magnetic data were also corrected for
the magnetization of the sample holder (a plastic bag).
Scheme 2. Structure and atom numbering scheme for MAC.
Experimental
All reagents and solvents were purchased from commercial
suppliers and used without further purification. The organic 2,5-
dpp ligand and the [Mn(MAC)(H2O)2]Cl2·4H2O complex were
prepared according to the literature.2b,15
X-ray data collection and structure refinement
X-ray diffraction data on single crystals of 1 and 2 were
collected at room temperature with a Bruker-Nonius X8-APEXII
CCD area detector system by using graphite-monochromated
Mo-Kα radiation (λ = 0.71073 Å). The data were processed
through the SAINT17 reduction and SADABS18 absorption
software. A summary of the crystallographic data and structure
refinement for the two compounds is given in Table 1. The
structures were solved by direct methods and subsequently
Caution! Cyanides are highly toxic and should be handled with
great caution. We worked at the mmol scale and the
preparations were performed in a well-ventilated hood.
Concentrated aqueous solutions of sodium hypochlorite and
sodium hydroxide were used to transform the cyanide from the
waste into cyanate.
2 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins

Page 3 of 9
New Journal of Chemistry
Please do not adjust margins
Journal Name
completed by Fourier recycling using the SHELX-2013 software
ARTICLE
1
2
3
4
5
6
7
8
Results and discussion
View Article Online
DOI: 10.1039/C9NJ00420C
package,19 then refined by the full-matrix least-squares
refinements based on F2 with all observed reflections. All non-
hydrogen atoms of 1 and 2 except the oxygen atoms of the
seven water molecules of crystallization in 2 were refined
anisotropically. The latter were found disordered, as revealed
by the high thermal factors; ten sites were compatible with the
presence of water molecules of crystallization, only four of
them being refined with full occupancy (half occupancy was
assigned to the remaining six ones). All the hydrogen atoms of
the 2,5-dpp ligand (1 and 2), the tetraphenylphosphonium
cation (1) and the MAC ligand (2) were set in calculated
positions and refined isotropically using the riding model.
Hydrogen atoms of the uncoordinated water molecules in both
1 and 2 were neither found nor calculated. Note that there is a
discrepancy between the IUPAC nomenclature given for the
MAC ligand in the Introduction and the labelling scheme used
for 2 when refining the structure, for convenience reasons. The
final geometrical calculations and graphical manipulations were
performed using the Diamond program.20 Crystallographic data
have been deposited at the Cambridge Crystallographic Data
Centre and have been assigned CCDC reference numbers
1892383 (1) and 1892384 (2).
Syntheses and infrared spectroscopy
The binuclear octacyanido building block, (PPh4)2[CoIII (μ-
2
2,5-dpp)(CN)8]·2H2O, (1), was obtained through the same,
simple, one-pot synthetic method, used by us to prepare the
CoIII mononuclear cyanido complexes, PPh4[CoIIIL(CN)4] · nS,12a,b
(L = ethylenediamine (en), 2-(aminomethyl)pyridine (ampy),
1,10-phenanthroline (phen) and 4,4’-dimethyl-2,2’-bipyridine
(4,4’-dmbipy)) changing only the molar ratio between the metal
cation and the ligand (Co2+:2,5-dpp = 2:1 molar ratio). The aerial
oxidation of cobalt(II) to cobalt(III) in the presence of the
cyanide and 2.5-dpp groups, which are strong field ligands,
accounts for the obtaining of the Co(III) dinuclear complex from
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
a Co(II) salt.12a Further, the [CoIII (μ-2,5-dpp)(CN)8]2- complex
2
anion was reacted with [Mn(MAC)(H2O)2]2+, a complex cation
known as a stable species with two labile trans positions that
can be easily replaced with organic donors16e and
metalloligands.16a-d,f-i The reaction afforded the neutral chain 2,
III
[MnII(MAC)(μ-NC)2Co2 (μ-2,5-dpp)(CN)6]n·7nH2O, in which the
[Co2(μ-2,5-dpp)(CN)8]2- spacers connect the [Mn(MAC)]2+
nodes, the binuclear octacyanido species acting as
metalloligand toward the complex cations.
a
The infrared spectrum for 1 shows a strong intensity band
at 2130 cm-1 (Fig. S1, ESI†) which is assigned to the terminal
cyanide groups (triple carbon-nitrogen bond stretching). This
value agrees with those from the literature for cyanide groups
terminally bound to cobalt(III).12a,b,21 This band is shifted to
higher wavenumbers in the infrared spectrum of 2 (Fig. S2,
ESI†), at 2140 cm-1 and has a shoulder at 2160 cm-1, being
assigned to terminal and bridging cyanide ligands.12b The strong
IR peaks at 786, 724, 690 and 528 cm-1 present in 1 that are
Table 1. Crystal data and structure refinement for compounds 1 and 2
1
2
Formula
C70H54Co2N12O2P2 C37H47Co2MnN17O7
Fw
1275.05
Monoclinic
P21/c
1014.71
Triclinic
P–1
Crystal system
Space group
a/Å
b/Å
c/Å
α/°
β/°
γ/°
V/Ǻ3
Z
9.0615(2)
25.7607(5)
13.9161(3)
90
105.6720(10)
90
3127.68(11)
2
1.354
11.3470(11)
13.0729(12)
17.5444(16)
90.907(4)
102.483(4)
110.635(4)
2365.9(4)
2
+
absent in 2 suggest the presence of the PPh4 cations in the
former compound. Finally, the shift towards higher
wavenumbers of the υ(C=N) and υ(C=C) stretching of 2,5-dpp in
1 (1624 and 1585 cm-1) and 2 (1649 and 1580 cm-1) support the
coordination of this molecule to the metal atoms in these
compounds. All these spectroscopic features are confirmed by
the X-ray structures (see below).
Dc/g cm -3
1.424
T/K
μ/mm-1
293(2)
0.638
296(2)
1.019
Description of the crystal structures
The structure of 1 consists of tetraphenylphosphonium
cations, dinuclear [Co2 (μ-2,5-dpp)(CN)8]2- complex anions and
F(000)
1316
1046
III
Refl. collected
Refl. indep. [R(int)]
Data/restraints/param.
123588
7525 [0.0508]
7525 / 0 / 397
44741
water molecules of crystallization.
1 crystallizes in the
8900 [0.0391]
8900 / 173 / 544
1.069
monoclinic system as P21/c with half of the complex anion (the
second half being generated by the crystallographic inversion
center), one tetraphenylphosphonium cation and one
uncoordinated water molecule in the asymmetric unit, (see Fig.
1). Selected bond lengths and angles for 1 are listed in Table S1
in ESI†.
Each cobalt(III) cation is six-coordinate with one pyrazine
and one pyridyl nitrogen atoms from the 2,5-dpp ligand and
four carbon-cyanide atoms building a distorted octahedral
surrounding. The two nitrogen atoms from the chelating 2,5-
dpp ligand and two cyanide groups occupy the equatorial sites,
while the axial positions are filled by the two remaining cyanide
groups.
Goodness-of-fit on F2 (S)c 1.077
Final R indicesa,b
[I >2σ(I)]
R1 = 0.0380,
wR2 = 0.0870
R1 = 0.0504,
wR2 = 0.0936
0.319 / -0.303
R1 = 0.0525,
wR2 = 0.1632
R1 = 0.0639,
wR2 = 0.1732
1.100 / -0.474
R indices (all data)
Δρmax,min/ e Å-3
aR1 = ∑||Fo| – |Fc||/∑|Fo|. bwR2 = {[∑w(Fo2 – Fc2)2/∑w(Fo2)2]}1/2 and w = 1/[σ 2(Fo)2
+ (mP)2 + nP] with P = (Fo2 + 2Fc2)/3, m = 0.0386 (1) and 0.0997 (2), and n = 1.2291
(1) and 2.1948 (2). cS = [∑w(|Fo| – |Fc|)2/(No – Np)]1/2
.
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 3
Please do not adjust margins

Please do not adjust margins
New Journal of Chemistry
Page 4 of 9
ARTICLE
Journal Name
straight [175.6(2) to 178.71(17)o]. The intramolecular
cobalt···cobalt separation through the bridging
molecule is 6.6536(4) Å.
The water molecules of crystallization in 1 are confined into a
hydrophobic space and are terminally H-bonded to one of the
two axial cyanide groups at each CoIII site [O1w···N3 = 2.874(4)
Å], this interaction contributing to the stabilization of the
1
2
3
4
5
6
7
8
View Article Online
DOI: 10.1039/C9N2J0,50-4d2p0Cp
9
structure.
Both
the
complex
anions
and
the
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
tetraphenylphosphonium cations form, instead, extended
networks by means of several moderate-to-weak non-covalent
III
interactions. The [Co2 (μ-2,5-dpp)(CN)8]2- anions, in particular,
line-up through double C-H···N type of interactions [C4b-
H4b···N5 = 2.38 Å; symmetry code: (b) = x-1, y, z] involving the
outer pyridyl rings of the 2,5-dpp ligand and a CoIII-equatorially
bound cyanide group of an adjacent molecular anion along the
crystallographic a axis (see Fig. 2a). Weak C-H···N type
interactions [C1c-H1c···N4 = 2.65 Å; (c) = -x, -y, -z+1]
interconnecting the molecular anions along the crystallographic
c axis do also exist, generating supramolecular anionic layers
growing parallel to the ac plane (Fig. 2a). Similarly, the
tetraphenylphosphonium cations in 1 arrange beautifully in a
row through uncommon, concerted edge-to-face phenyl
embraces22 involving three of the four phenyl rings along the
crystallographic c axis (Figs. 2b), with C-H···ring centroid
distances ranging from 3.33 to 3.41 Å. The fourth phenyl ring is
responsible for the interconnection of such 1D motifs along the
crystallographic a axis, with a C-H···ring centroid distance of
about 3.01 Å.
Figure 1. A view of the [Co2III(μ-2,5-dpp)(CN)8]2- complex anion of 1, also showing its
immediate water and tetraphenylphosphonium cations surrounding. Hydrogen bonds
and - stacking interactions are shown as black and pale grey dashed lines, respectively.
Labels are added on selected atoms of the asymmetric unit only and the hydrogen atoms
were omitted for clarity [Symmetry code: (a) = -x, -y, -z].
The reduced bite angle of the 2,5-dpp molecule [82.12(6)o for
N1-Co1-N2] is the main reason for the distortion of the
octahedral environment. The Co-C bond lengths vary from
1.866(2) to 1.908(2) Å and the Co-N bonds are larger, averaging
at 1.963(1) Å. The bond lengths and angles at the cobalt(III) ion
are very close to those of the tetracyanido-cobalt(III) species
reported to date.12a,b,21 The Co-C-Ncyanide angles are almost
Fig. 2. (a) View of adjacent 1D motifs built by vicinal [Co2III(μ-2,5-dpp)(CN)8]2- anions in 1 through C-H···N contacts (black dashed lines) along the crystallographic a axis. Yellow dashed
lines indicate weaker C-H···N interactions along the crystallographic c axis, leading to supramolecular anionic layers growing parallel to the ac plane in 1. (b) View of the 1D motif
along the crystallographic c axis built by edge-to-face phenyl embraces between vicinal tetraphenylphosphonium cations in 1. Dashed lines indicate the phenyl rings involved in the
embracing (A, C and D). (c) A view of the supramolecular cationic layer growing parallel to the ac plane, arising from the combination of the tetraphenylphosphonium phenyl
embracing along the c axis together with multiple C-H··· interactions along the a axis in 1, the latter involving phenyl rings B and D.
4 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins

Please do not adjust margins
Page 5 of 9
New Journal of Chemistry
1
2
3
4
5
6
7
View Article Online
DOI: 10.1039/C9NJ00420C
ARTICLE
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
The combination of the tetraphenylphosphonium phenyl water content in 2 could not be determined and the declared
embraces along the c axis with multiple C-H··· interactions value represents our best estimate based on all data in hand
along the a axis gives rise to supramolecular cationic layers (elemental analyses, magnetism, crystallography). The further
growing parallel to the crystallographic ac plane in 1 (Fig. 2c). development of the chain is determined by a second cyanido
Thus, both anionic and cationic supramolecular layers group [C15-N5] belonging to the dicobalt(III) metalloligand
extending in the crystallographic ac plane are present in 1, and which coordinates to an adjacent MnII metal ion. A fragment of
they alternate along the b axis (Fig. 3). Interconnections the heterobimetallic alternating CoIII-MnII chain of 2 is shown in
between the extended anionic and cationic portions of the Fig. 4c, while selected bond distances and angles for this
crystal packing of 1 are provided by weak - stacking between compound are listed in Table S2 in ESI†. Each MnII ion is
the outer pyridyl rings of the 2,5-dpp ligand of the complex confined within the pentadentate macrocyciclic MAC ligand and
anions and a phenyl group of the tetraphenylphosphonium it is seven-coordinate: five in-plane nitrogen atoms from the
cations, the centroid-to-plane distances averaging at 3.72 Å and MAC ligand (N13, N14, N15, N16 and N17 set of atoms) and two
the dihedral angle between the rings being 19.3° (see Figs. 1 and axial cyanido nitrogen atoms from two dicobalt(III) units build a
3).
distorted pentagonal bipyramidal environment around the
manganese atom (see Fig. 4). The two cyanido bridges at the
manganese side are bent, the values of the Mn-N-C angles being
159.0(3) and 161.1(3)° at N9 and N5a, respectively. The Mn-
Ncyanido bond lengths [mean value 2.275(4) Å] are shorter than
the Mn-Nimine [Mn1-N14 and Mn1-N15, averaging at 2.302(4) Å]
and the Mn-Namino [Mn1-N16 and Mn1-N17, averaging at
2.297(4) Å] distances, but longer than the Mn-Npyridyl bond
length [Mn1-N13 = 2.210(2) Å]. These structural pattern
regarding the MnII environment in 2 agrees with those observed
in previous structures containing the {MnII(MAC)}2+ fragment.16
Fig. 3. Eclipsed view of a fragment of the crystal packing of 1 along the crystallographic
a axis, showing anionic and cationic layers intercalating each other in the direction of the
b axis, and being interconnected through - stacking between the 2,5-dpp ligand and
the tetraphenylphosphonium cations (grey dashed lines). Hydrogen atoms and water
molecules of crystallizations are omitted for clarity. Yellow and orange dashed lines
indicate non-covalent interactions relevant to the development of anionic and cationic
layers, respectively (see also Figs. 1-2). The four phenyl rings (noted A, B, C and D) on the
cation are defined as in Figs. 2b-c.
Compound 2 crystallizes in the triclinic space group P-1. Its
structure consists of neutral zig-zag chains of general formula
III
[MnII(MAC)(μ-NC)2Co2 (μ-2,5-dpp)(CN)6]n·7nH2O running along
Fig. 4. (a) Perspective view of the repeating unit of the heterobimetallic alternating CoIII-
MnII chain of 2. (b) View of the asymmetric unit, comprising the fragment shown in (a)
and the seven disordered water molecules of crystallization occupying ten different sites
with either full (dark red spheres) or half occupancy (light red spheres). (c) View of a
fragment of the chain running along the crystallographic b axis. Labels are put on
selected atoms only. Hydrogen atoms are not shown for clarity [Symmetry codes: (a) =
x, y-1, z; (b) = x, y+1, z.]
the crystallographic b axis. The asymmetric unit comprises a
[MnII(MAC)]2+ cationic moiety connected to a [Co2 (μ-2,5-
III
dpp)(CN)6]2- anionic fragment through a cyanido bridge [C19-
N9], plus the seven water molecules of crystallization
tentatively distributed over ten sites of which six with half
occupancy (Fig. 4a-b). It is worth to mention that the exact
Please do not adjust margins

Please do not adjust margins
New Journal of Chemistry
Page 6 of 9
ARTICLE
Journal Name
1
2
3
4
5
6
7
As in 1, the two cobalt(III) ions in 2 are six-coordinate in an respectively, values which are very close to the corresponding
octahedral environment formed by two nitrogen atoms bite angle in 1. The Co-Ccyanido bond lengths have values in the
belonging to the bridging 2,5-dpp ligand and four cyanide- range 1.865(3)-1.900(4) (at Co1) and 1.871(4)-1.905(4) Å (at
carbon atoms. The bite angles of the bis-chelating 2,5-dpp Co2), while the Co-N2,5-dpp distances are generally longer [mean
molecule are 82.14(11) and 81.98(11)o at Co2 and Co1 values 1.970(3) (at Co1) and 1.971(3) Å (at Co2)].
View Article Online
DOI: 10.1039/C9NJ00420C
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Fig. 5. (a) View of fragments of vicinal heterometallic chains in the bc plane in 2, coupled into stripes by means of face-to-face - stacking interactions involving the pyridiyl ring of
the MAC ligand (grey dashed lines). (b) A view of the crystal packing of 2 along the crystallographic b axis, showing the arrangement of vicinal supramolecular stripes in the ac plane,
some of which being highlighted in green for clarity. Hydrogen atoms and water molecules of crystallization are omitted for clarity.
Fig. 6. (a) Perspective view of a fragment of the crystal packing of 2 along the crystallographic c axis, showing in (b) the disordered water molecules (van der Waals model) filling the
channels which develop in the same direction.
The values of the Co-C-Ncyanide angles are close to linearity [with distance is 8.5873(13) Å. The intrachain angles between the
values varying in the ranges 174.9(3)-178.9(4)° for Co1 and metal ions are almost right [Co1-Co2-Mn1 = 98.381(12)o and
175.7(3)-178.0(5)° for Co2]. Bond distances and angles within Mn1b-Co1-Co2 = 96.076(12)o; symmetry code: (b) = x, -1+y, z]
the cyanido-bearing CoIII fragments (see Table S2 in ESI†), are in or straight [Co1a-Mn1-Co2 = 175.408(13)°].
agreement with those observed in 1.
Two chains are coupled into a stripe by means of face-to-
The shortest CoIII···MnII separation across the bridging face, parallel by symmetry, - stacking interactions involving
cyanide is 5.2178(8) Å, while the CoIII···CoIII separation through the pyridyl ring of neighboring MAC ligands (Fig. 5), whose
the bridging 2,5-dpp ligand is 6.6824(8) Å, a value very similar interplanar distance is about 3.39 Å. Such stripes are closely
to that observed in 1. The intrachain MnII···MnII separation is packed in the crystallographic ac plane, however no further
13.0729(12) Å whereas the shortest interchain MnII···MnII relevant - stacking, C-H··· or C-H···N interactions can be
6 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins

Page 7 of 9
New Journal of Chemistry
Please do not adjust margins
Journal Name
ARTICLE
1
2
3
4
5
6
7
noted. Rather, viewed along the crystallographic c axis, the 3D towards the peripheral cyanide groups. Being a robust
View Article Online
packing of 2 reveals the presence of small channels, where all diamagnetic species, complex 1 opens aDnOeIw: 10a.v10e3n9u/Ce9fNoJr0m04e2t0aCl
the disordered lattice water molecules are located (Fig. 6), and assembling in the near future when used as a metalloligand
they are involved into an extensive network of hydrogen bonds versus either preformed metal complexes whose coordination
which contribute to the stabilization of the crystal packing.
sphere is unsaturated or well fully solvated metal ions.
8
9
Magnetic properties
Conflicts of interest
There are no conflicts to declare.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Compound 1 is a diamagnetic species as expected for a
dicobalt(III) complex where each metal centre is six-coordinated
by four strong field cyanide ligands and one pyridyl and one
pyrazine nitrogen atoms from a bis-bidentate 2,5-dpp molecule.
The magnetic properties of 2 in the form of χMT versus T plot [χM
is the magnetic susceptibility per CoIII2MnII unit) are shown in
Fig. 7. At room temperature, χMT for 2 is ca. 4.38 cm3 mol-1 K, a
value which is as expected for a magnetically isolated high-spin
MnII with gMn = 2.0, the CoIII being diamagnetic. Upon cooling,
this value remains constant until 10 K and it further exhibits a
very small decrease to 4.22 cm3 mol-1 K at 1.9 K. This behaviour
corresponds to a practically magnetically isolated spin sextet
with a g value of 2.005(3).
Acknowledgements
This work was financially supported by the Romanian National
Authority for Scientific Research (CNCS-UEFISCDI) (Projects PN-
II-RU-TE-2014-4-1556 and PN-III-P1-1.1-MC-2018-1877), the
Italian Ministero dell’Istruzuione dell’Università e della Ricerca
(MIUR) and the Ministerio Español de Economía
Competitividad (MINECO) (Project CTQ2016-75068P and
Unidad de Excelencia María de Maetzu MDM-2015-0538).
y
Notes and references
1
(a) C. R. K. Glasson, L. F. Lindoy and G. V. Meehan, Coord.
Chem. Rev., 2008, 252, 940-963; (b) L. Salassa, Eur. J. Inorg.
Chem., 2011, 4931-4947; (c) R. D. Hancock, Chem. Soc. Rev.,
2013, 42, 1500-1524; (d) S. Culham, P.-H. Lanoë, V. L. Whittle,
M. C. Durrant, J. A. Gareth Williams and V. N. Kozhevnikov,
Inorg. Chem., 2013, 52, 10992-11003; (e) B. Colasson, A. Credi
and G. Ragazzon, Coord. Chem. Rev., 2016, 325, 125-134; (f)
B. Floris, M. P. Donzello, C. Ercolani and E. Viola, Coord. Chem.
Rev., 2007, 347, 115-140; (g) M. Attwood and S. S. Turner,
Coord. Chem. Rev., 2017, 353, 247-277; (h) V. Bravec and J.
kaspatkova, Coord. Chem. Rev., 2018, 376, 75-94; (i) A. M.-H.
Yip and K. K.-W. Lo, Coord. Chem. Rev., 2018, 361, 138-163.;
(j) A. P. Sadimenko and O. O. Okoh, Adv. Heterocyclic Chem.,
10.1016/bs.aihch.2018.06.001.
Fig. 7. Plot of χMT vs. T for 2: (o) experimental; (__) best-fit curve through a Curie law (see
text). The inset shows the thermal dependence of the magnetization for 2 at 2.0 K. The
dashed line corresponds to the Brillouin function for a magnetically isolated S = 5/2 with
g = 2.005.
2
3
(a) A. Escuer, T. Comas, R. Vicente and J. Ribas, Transition Met.
Chem., 1993, 18, 42-44; (b) C. Yuste, A. Bentama, S.-E. Stiriba,
D. Armentano, G. De Munno, F. Lloret and M. Julve, Dalton
Trans., 2007, 5190-5200; (c) L. Donato, C. E. McCusker, F. N.
Castellano, E. Zysman-Colman, Inorg. Chem., 2013, 52, 8495-
8504.
(a) S. Serroni and G. Denti, Inorg. Chem., 1992, 31, 4251-4255;
(b) A. Neels and H. Stoeckli-Evans, Inorg. Chem., 1999, 38,
6164-6170.
This is corroborated by the field dependence of the
magnetization (M) of 2 at 2.0 K, M at 5 T tending to a value of
5.0 BM (see inset of Fig. 7).
4
5
M. Al-Anber, N. Wetzold, B. Walfort, T. Rüffer and H. Lang,
Inorg. Chim. Acta, 2013, 398, 124-131.
E. C. Constable, H. Eriksson, C. E. Housecroft, B. M. Kariuki, E.
Nordlander and J. Olsson, Inorg. Chem. Commun., 2001, 4,
749-752.
Conclusions
The first heterobimetallic 3d cyanido complex was obtained
and crystallographically characterized: a one pot reaction under
ambient conditions, involving the 2,5-dpp organic molecule,
cobalt(II) ions and cyanide anions affords the octacyanido
6
T. Tsubomura, S. Enoto, S. Endo, T. Tamane, K. Matsumoto
and T. Tsukuda, Inorg. Chem., 2005, 44, 6373-6378.
A. Neels and H. Stoeckli-Evans, Chimia, 1993, 47, 198-202.
(a) A. Bentama, O. Schott, J. Ferrando-Soria, S.-E. Stiriba, J.
Pasán, C. Ruiz-Pérez and M. Julve, Inorg. Chim. Acta, 2013,
389, 52-59; (b) C. Yuste, A. Bentama, N. Marino, D.
Armentano, F. Setifi, S. Triki, F. Lloret and M. Julve,
Polyhedron, 2009, 28, 1287-1294.
R. Lescouëzec, L. M. Toma, J. Vaissermann, M. Verdaguer, F.
S. Delgado, C. Ruiz-Pérez, F. Lloret and M. Julve, Coord. Chem.
Rev., 2005, 249, 2691-2729; (b) M.-G. Alexandru, D. Visinescu,
B. Braun-Cula, F. Lloret and M. Julve, Eur. J. Inorg. Chem.,
2018, 349-359; (c) M.-G. Alexandru, D. Visinescu, S. Shova, W.
7
8
III
complex (Ph4P)2[Co2 (μ-2,5-dpp)(CN)8]·2H2O (1) where the 2,5-
dpp molecule acts as a bis-bidentate ligand and the cobalt(II) ion
has become cobalt(III) by air oxidation. This cyanido building-
block was used as
a
metalloligand towards the
9
[Mn(MAC)(H2O)2]2+ complex cation to construct
a
III
heterometallic
chain,
[MnII(MAC)(μ-NC)2Co2 (μ-2,5-
dpp)(CN)6]n·7nH2O. This result proves the ability of the cyanide-
bearing cobalt(III) precursor to act as an efficient spacer
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 7
Please do not adjust margins

Please do not adjust margins
New Journal of Chemistry
Page 8 of 9
ARTICLE
Journal Name
1
2
3
4
5
6
7
8
9
X. C. Oliveira, F. Lloret and M. Julve, Dalton Trans., 2018, 47,
View Article Online
DOI: 10.1039/C9NJ00420C
6005-6017.
10 Y.-H. Li, W.-R. He, X.-H. Ding, S. Wang, L.-F. Cui and W. Huang,
Coord. Chem. Rev., 2012, 256, 2795-2815.
11 (a) L. M. Toma, C. Ruiz-Pérez, F. Lloret and M. Julve, Inorg.
Chem., 2012, 51, 1216-1218; (b) L. M. Toma, J. Pasán, C. Ruiz-
Pérez, F. Lloret and M. Julve, Dalton Trans., 2012, 41, 13716-
13726; (c) L. M. Toma, C. Ruiz-Pérez, J. Pasán, W.
Wernsdorfer, F. Lloret and M. Julve, J. Am. Chem. Soc., 2012,
134, 15265-15268; (d) M.-G. Alexandru, D. Visinescu, M.
Andruh, N. Marino, D. Armentano, J. Cano, F. Lloret and M.
Julve, Chem. Eur. J., 2015, 21, 5429-5446; (e) M.-G. Alexandru,
D. Visinescu, S. Shova, M. Andruh, F. Lloret and M. Julve,
Inorg. Chem., 2017, 56, 2258-2269.
12 (a) M.-G. Alexandru, D. Visinescu, N. Marino, G. De Munno, J.
Vallejo, F. Lloret and M. Julve, Eur. J. Inorg. Chem., 2014, 4564-
4572; (b) M.-G. Alexandru, D. Visinescu, N. Marino, G. De
Munno, F. Lloret and M. Julve, RSC Adv., 2015, 5, 95410-
95420; (c) M.-G. Alexandru, D. Visinescu, S. Shova, F. Lloret
and M. Julve, Dalton Trans., 2017, 46, 39-43.
13 (a) R. Lescouëzec, J. Vaissermann, C. Ruiz-Pérez, F. Lloret, R.
Carrasco, M. Julve, M. Verdaguer, Y. Dromzée, D. Gatteschi
and W. Wernsdorfer, Angew. Chem. Int. Ed., 2003, 42, 1483-
1486; (b) L. M. Toma, R. Lescouëzec, J. Pasán, C. Ruiz-Pérez, J.
Vaissermann, J. Cano, R. Carrasco, W. Wernsdorfer, F. Lloret
and M. Julve, J. Am. Chem. Soc., 2006, 128, 4842-4853.
14 J.-M. Herrera, S. G. Baca, H. Adams and M. D. Ward,
Poyhedron, 2006, 25, 869-875.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
15 O. Jiménez-Sandoval, D. Ramírez-Rosales, M. del Jesús
Rosales-Hoz, M. E. Sosa-Torres, R. Zamorano-Ulloa, J. Chem.
Soc., Dalton Trans. 1998, 1551-1556.
16 (a) A. K. Sra, M. Andruh, O. Kahn, S. Golhen, L. Ouahab and J.
V. Yakhmi, Angew. Chem. Int. Ed., 1999, 38, 2606-2609; (b) A.
K. Sra, J.-P. Sutter, P. Guionneau, D. Chasseau, J. V. Yakhmi and
O. Kahn, Inorg. Chim. Acta, 2000, 300-302, 778-782; (c) G.
Rombaut, S. Golhen, L. Ouahab, C. Mathonière and O. Kahn,
J. Chem. Soc., Dalton Trans., 2000, 3609-3614; (d) S. Tanase,
M. Andruh, N. Stanica, C. Mathonière, G. Rombaut, S. Golhen
and L. Ouahab, Polyhedron, 2003, 22, 1315-1320; (e) C.
Paraschiv, J.-P. Sutter, M. Schmidtmann, A. Müller, M.
Andruh, Polyhedron, 2003, 22, 1611-1615; (f) C. Paraschiv, M.
Andruh, Y. Journaux, Z. Žak, N. Kyritsakasd and L. Ricard, J.
Mater. Chem., 2006, 16, 2660-2668; (g) Q.-L. Wang, Y.-Z.
Zhang, H. Southerland, A. V. Prosvirin, H. Zhao and K. R.
Dunbar, Dalton Trans., 2014, 43, 6802-6810; (h) K. Wang, B.
Xia, Q.-L. Wang, Y. Ma, D.-Z. Liao and J. Tang, Dalton Trans.,
2017, 46, 1042-1046; (i) C. Pichon, B. Elrez, V. Béreau, C.
Duhayon and J.-P. Sutter, Eur. J. Inorg. Chem., 2018, 340-348.
17 SAINT, version 6.45, Bruker Analytical X-ray Systems,
Madison, WI, 2003.
18 G. M. Shieldrick. SADABS Program for Absorption Correction,
version 2.10, Analytical X-ray Systems, Madison, WI, 2003.
19 (a) G. M. Sheldrick, Acta Crystallogr., 2015, C71, 3-8; (b) G. M.
Sheldrick, Acta Crystallogr., 2008, A64, 112-122; (c) SHELXTL-
2013/4, Bruker Analytical X-ray Instruments, Madison, WI,
2013.
20 Diamond - Crystal and Molecular Structure Visualization.
Crystal Impact - Dr. H. Putz & Dr. K. Brandenburg GbR,
Kreuzherrenstr. 102, 53227 Bonn, Germany
21 G. Lyubartseva and S. Parkin, Acta Crystallogr., 2010, E66,
m475-476.
22 I. Dance and M. Scudder, Chem. Eur J., 1996, 2, 481-486.
8 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins

Page 9 of 9
New Journal of Chemistry
1
2
3
4
View Article Online
DOI: 10.1039/C9NJ00420C
5
6
Table of contents
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
III
The first bimetallic 3d cyanido-bearing complex with 2,5-dpp as a bridge, (Ph4P)2[Co2 (-2,5-
dpp)(CN)8]·2H2O, is obtained and used as a metalloligand towards the [Mn(MAC)(H2O)2]2+
cation to build a {CoIIIMnII} heterobimetallic chain.