A synthetic and crystal structure study of a collection of coordination polymers based on alkaline aroylhydrazonates

Article abstract of DOI:10.1016/j.poly.2015.08.013

The reactions of two aroylhydrazone ligands H₂L^S and H₂L^Ac with alkaline Li(I), Na(I), K(I) and Ba(II) metal ions afforded nine new coordination polymers with different dimensionalities. These illustrate the ionic radii, the ligand substitution and the solvent influence on the formation of the final product. Interestingly, one of them shows porous structure with a 40% unoccupied volume.

Full text of DOI:10.1016/j.poly.2015.08.013

Polyhedron 100 (2015) 359–372
Contents lists available at ScienceDirect
Polyhedron
journal homepage: www.elsevier.com/locate/poly
A synthetic and crystal structure study of a collection of coordination
polymers based on alkaline aroylhydrazonates
c
c
d,
David Specklin a, Samir Mameri a,b, , Edward Loukopoulos , George E. Kostakis , Richard Welter
⇑
⇑
a Institut de Chimie, UMR 7177, Université de Strasbourg, 4 rue Blaise Pascal, 67000 Strasbourg, France
b Laboratoire de Chimie Moléculaire, UMR 7509, Université de Strasbourg, 25 rue Becquerel, 67087 Strasbourg, France
c Department of Chemistry, School of Life Sciences, University of Sussex, Brighton BN1 9QJ, UK
d Institute of Plant Molecular Biology, UPR 2357, Université de Strasbourg, 28 rue Goethe, 67000 Strasbourg, France
a r t i c l e i n f o
a b s t r a c t
The reactions of two aroylhydrazone ligands H2LS and H2LAc with alkaline Li(I), Na(I), K(I) and Ba(II) metal
ions afforded nine new coordination polymers with different dimensionalities. These illustrate the ionic
radii, the ligand substitution and the solvent influence on the formation of the final product. Interestingly,
one of them shows porous structure with a 40% unoccupied volume.
Article history:
Received 22 June 2015
Accepted 6 August 2015
Available online 1 September 2015
Ó 2015 Elsevier Ltd. All rights reserved.
This paper is dedicated to the Emeritus of
Prof. Pierre Braunstein, member of the
French Académie des Sciences.
Keywords:
Ligand design
Crystal structure
Coordination polymers
MOFs
Alkali metals
1. Introduction
Interestingly, a recent study from Matoga et al. showed that this
class of organic moieties can be used along with Cu(II) metal ions
The synthesis of new coordination polymers (CPs) or metal
organic frameworks (MOFs) has captured researchers’ interest
owing to the variety of compositions and topologies of the pro-
duced compounds [1–9] together with their interesting functional
properties and applications [10–20]. The properties of such sys-
tems are controlled by their chemical composition and structure,
which are easily monitored by simply varying the reactants and
reaction conditions. Considerable attention has been given toward
developing the ability to control the reactions so that the products
can be engineered towards desired properties [21,22].
Aroylhydrazones is a class of excellent multidentate organic
ligands that has been extensively studied for the chemistry of tran-
sition metals (3d), what has resulted in polynuclear coordination
clusters [23,24], also with interesting biological properties, e.g.
antiamoebic activity [25], DNA synthesis inhibition or antiprolifer-
ative behaviour [26–28], anticonvulsant, analgesic, antiinflamma-
tory, antiplatelet, antitubercular and antitumoral activities [29].
to produce water soluble CPs [30]. We also reported the synthesis
and properties of a CP with an aroylhydrazone based ligand coor-
dinating to a Mn centre [31].
A comprehensive survey shows that a systematic study of the
influence of the alkali metal ions and the solvent on the construc-
tion of alkali aroylhydrazonates based CPs has not been reported so
far. We have thus embarked on a program of synthesizing new
aroylhydrazone ligands, so far with a sulfonate functional group
(SO3), aiming towards producing new water soluble CPs which
could also be suitable for attachment to a variety of surfaces
including biological molecules.
Having all these in mind, we synthesized the two new organic
ligands H2LS and H2LAc (see Scheme 1) and studied their coordina-
tion abilities to alkali metal ions, i.e. Li(I), Na(I), K(I) and Ba(II)
cations. We report herein the syntheses, structure determination,
and topological evaluation of ten new compounds (including both
ligands in Scheme 1), i.e. [pyr][HLAc] (pyr = 3,5,5-trimethyl-4,5-di-
hydro-1H-pyrazolium), K2(LS)(DMF)2, Li2(LS)(H2O)5ꢀH2O (C1),
Na4(LS)(H2O)22ꢀ2H2O (C2), K2(LS)(H2O)2 (C3), Ba(LS)(H2O)4 (C4),
[Li(LAc)(H2O)2][Li(H2O)4]ꢀH2OꢀOC3H6 (C5), Na2(LAc)(H2O)2 (C6),
K2(LAc)(H2O) (C7) and Ba(LAc)(H2O)4ꢀH2O (C8), which were
⇑
Corresponding authors at: Institute of Plant Molecular Biology, UPR 2357,
Université de Strasbourg, 28 rue Goethe, 67000 Strasbourg, France (R. Welter).
E-mail addresses: mameri@unistra.fr (S. Mameri), welter@unistra.fr (R. Welter).
http://dx.doi.org/10.1016/j.poly.2015.08.013
0277-5387/Ó 2015 Elsevier Ltd. All rights reserved.

360
D. Specklin et al. / Polyhedron 100 (2015) 359–372
Scheme 1. The protonated form of the two new aroylhydrazone ligands described in this study.
prepared from 5-sulfosalicyloylhydrazono-1,3-dithiolane potas-
sium salt K2LS or from the hydrazinium salt of the 5-sulfosalycilic
hydrazide, respectively (see Schemes 2 and 3).
[Li(LAc)(H2O)2][Li(H2O)4]ꢀH2OꢀOC3H6 (C5), Na2(LAc)(H2O)2 (C6),
K2(LAc)(H2O) (C7) and Ba(LAc)(H2O)4ꢀH2O (C8) were prepared from
the hydrazinium salt of the 5-sulfosalycilic hydrazide. Crystal
structure of pyrazolium salt derivative of the ligand H2LAc was also
determined and is discussed in the present study as well. All 10
compounds were characterized by structural resolution using sin-
gle crystal X-ray diffraction using the following procedure: diffrac-
tion measurements were performed at 173 K by using a Nonius
Kappa-CCD or a Bruker APEX-II DUO Kappa-CCD diffractometer
2. Experimental
2.1. Materials and instrumentation
Reactions were carried out under aerobic conditions using stan-
dard Schlenk techniques with chemicals and solvents obtained
from commercial sources and used as received without further
purification. Anhydrous solvents were either obtained from com-
mercial sources and used as received without further purification
or purified using a solvent purification system (MBraun SPS). TLC
was performed with silica gel plates (Merck, 60F-254). Flash chro-
with Mo K radiation (Mo Ka = 0.71073 Å). The crystal structures
were solved by means of Direct Methods and refined employing
full-matrix least squares on F2 (SHELXL-97). All non-hydrogen atoms
were refined anisotropically, and the hydrogen atoms of organic
ligands were introduced using the riding model (SHELXL-97). Crystal
data and refinement details are given in Tables X1, X2 and X3 in
Supplementary materials.
matography was performed with 40–63 l
m SiO2. 1H, 13C, and 31P
NMR spectra were recorded at ambient temperature at 300, 400,
500 or 600 MHz with tetramethylsilane (TMS) as an internal stan-
dard (Bruker AVANCE). Chemical shifts (d) of samples in CDCl3,
CH3OD, [D6]acetone, [D6]DMSO or D2O are in parts per million
(ppm). The splitting patterns are designated as: s = singlet,
brs = broad singlet, d = doublet, t = triplet, q = quartet, and
m = multiplet. Coupling constants (J) between two nuclei sepa-
rated by n chemical bonds are denoted in Hertz (Hz). FTIR spectra
were measured in the range 4000–400 cmꢁ1 with a Nicolet 67000
FT-IR (ATR mode, ZnSe). Elemental analyses were obtained at the
analytical facility of the IUT Robert Schuman, University of
Strasbourg.
2.2. Synthesis of the compounds
2.2.1. Synthesis of 5-sulfosalicyloylhydrazono-1,3-dithiolane (H2LS)
The ligand H2LS was obtained in 4 steps following the procedure
described hereafter.
2.2.1.1. 5-Sulfosalycilic methyl ester (2). 5-Sulfosalycilic acid (4 g,
18.3 mmol) was refluxed in MeOH (50 mL) for 18 h. After evapora-
tion of the solvent, title ester was isolated as a white powder
(quant.). 1H NMR (DMSO-d6): d = 8.03 (d, J = 2.2 Hz, 1H), 7.69 (dd,
J = 8.6 Hz, J = 2.2 Hz, 1H), 6.92 (d, J = 8.6 Hz, 1H), 4.68 (brs), 3.90
(s, 3H) ppm.
Single crystals of complexes K2(LS)(DMF)2, Li2(LS)(H2O)5ꢀH2O
(C1), Na4(LS)(H2O)22ꢀ2H2O (C2), K2(LS)(H2O)2 (C3) and Ba(LS)
(H2O)4 (C4) were prepared from 5-sulfosalicyloylhydrazono-1,3-
dithiolane potassium salt K2LS, whilst single crystals of complexes
2.2.1.2. 5-Sulfosalycilic hydrazide (3). Ester 2 (4.04 g, 17.4 mmol)
and hydrazine monohydrate (1.1 mL, 20.9 mmol, 1.2 eq) were
Scheme 2. Synthetic route to K2LS.

D. Specklin et al. / Polyhedron 100 (2015) 359–372
361
Scheme 3. Synthetic pathways to MxLAc. M = metal; x = 2 and y = 1 for Li, Na and K; x = 1 and y = 2 for Ba.
dissolved in MeOH (50 mL) and vigorously stirred for 18 h at room
temperature. The resulting white precipitate was filtered off,
washed with Et2O (50 mL), and recrystallized from MeOH to yield
titled compound as a white powder (69%). 1H NMR (DMSO-d6):
d = 10.55 (s, 1H), 8.62 (brs, 2H), 8.03 (d, J = 2.1 Hz, 1H), 7.69 (dd,
J = 8.5 Hz, J = 2.1 Hz, 1H), 6.92 (d, 8.5 Hz, 1H), 4.3 (brs, 2H) ppm.
200 mL of THF has resulted in the precipitation of titled salt 4 as
a white solid, which was further recrystallized in MeOH (quant.).
1H NMR (DMSO-d6): d = 8.10 (d, J = 2 Hz, 1H), 7.53 (dd, J = 8.5 Hz
and 2 Hz, 1H), 6.77 (d, J = 8.5 Hz, 1H), 6.54 (brs, 9H) ppm.
2.2.2.2. 5-Sulfosalicyloylhydrazono-2-propane pyrazolium salt [pyr]
[HLAc
] {pyr: 3,5,5-trimethyl-4,5-dihydro-1H-pyrazolium}. Acetone
2.2.1.3. 5-Sulfosalicyloylhydrazono-1,3-dithiolane potassium salt (K2-
LS). KOH (2.307 g, 41 mmol, 3.4 eq) was added to a vigorously stir-
red solution of 2 (2.764 g, 11.9 mmol) in DMF (40 mL). The
resulting mixture was further stirred for 12 h at room temperature,
after which the drop-by-drop addition of CS2 (0.745 mL,
12.3 mmol, 1.03 eq). After further stirring for 12 h at room temper-
ature, 1,2-dibromoethane (1.06 mL, 12.3 mmol, 1.03 eq) was added
drop-by-drop, and the stirring further continued for 6 h at room
temperature. Then, the resulting yellow solution was dropped into
CH2Cl2 (200 mL), which has resulted in a white precipitate. Final
(3 mL) was added at room temperature to a solution of 4 (50 mg,
0.19 mmol) in H2O (1 mL) which resulted in the precipitation of
titled pyrazolium 5-sulfosalicyloylhydrazono-2-propane salt as a
white powder (quant.). Colourless single crystals suitable for X-
ray diffraction were obtained by the slow diffusion of acetone to
an aqueous solution of this salt. 1H NMR (DMSO-d6): d = 11.9
(brs, 1H), 11.2 (brs, 2H), 11.0 (brs, 1H), 8.21 (d, J = 1.5 Hz, 1H),
7.58 (dd, 8.3 Hz, J = 1.5 Hz, 1H), 6.90 (d, J = 8.3 Hz, 1H), 2.98 (s,
2H), 2.13 (s, 3H), 2.03 (s, 3H), 1.93 (s, 3H), 2.13 (s, 6H).
recrystallization from MeOH gave K2LS as
a white powder.
2.2.2.3. 5-Sulfosalicyloylhydrazono-2-propane (H2LAc). Acidification
to pH 1 of an aqueous solution of [pyr][HLAc] with diluted HCl solu-
tion (1 M in water) followed by addition of acetone led to the pre-
Yield = 34%. 1H NMR (DMSO-d6): d = 8.11 (d, J = 1.9 Hz, 1H), 7.40
(dd, J = 8.1 Hz and 1.9 Hz, 1H), 6.64 (d, J = 8.1 Hz, 1H), 3.64 (t,
J = 5.4 Hz, 2H), 3.51 (t, J = 5.4 Hz, 2H) ppm.
cipitation of titled acidic ligand H2LAc
.
2.2.1.4. 5-Sulfosalicyloylhydrazono-1,3-dithiolane (H2LS). Acidifica-
tion to pH 1 of an aqueous solution of K2LS with diluted HCl solu-
tion (1 M in water) followed by addition of acetone led to the
precipitation of titled acidic ligand H2LS. 1H NMR (DMSO-d6):
d = 12.0 (brs, 1H), 11.1 (brs, 1H), 8.18 (d, J = 2 Hz, 1H), 7.57 (dd,
J = 8.4 Hz and 2 Hz, 1H), 6.92 (d, J = 8.4 Hz, 1H), 3.75–3.71 (m,
2H), 3.59–3.51 (m, 2H) ppm. 1H NMR (D2O): d = 8.17 (brs,
J = 2 Hz, 1H), 7.70 (d, J = 8.6 Hz, 1H), 6.94 (d, J = 8.6 Hz, 1H), 3.72–
3.68 (m, 2H), 3.58–3.54 (m, 2H) ppm.
2.2.3. Synthesis of the CPs
The diffusion of Et2O to a solution of K2LS (10 mg) in DMF (2 mL)
has led, after 1 day, to K2(LS)(DMF)2 as thin colourless needles.
2.2.3.1. Synthesis of Li2(LS)(H2O)5ꢀH2O (C1). A solution of K2LS in
water (100 mg in 2 mL) was acidified to pH 1 using dil. aq. HCl
(1 M). Then, aq. LiOH (5% w/w) was added to reach basic pH 14.
Addition of acetone (20 mL) led to the precipitation of a white
powder (65 mg), which was further washed with cold water
(5 mL) and THF (20 mL). Among this quantity, 10 mg were solubi-
lized in water (1 mL) and let to diffusion with acetone. Colourless
crystalline needles of title lithium complex were isolated after
3 days.
2.2.2. Synthesis of 5-sulfosalicyloylhydrazono-2-propane (H2LAc
)
The ligand H2LAc was obtained in 5 steps following the proce-
dure described hereafter.
2.2.2.1. 5-Sulfosalycilic hydrazide hydrazinium salt (4). 5-Sulfosaly-
cilic acid (4 g, 18.3 mmol) was refluxed in MeOH (50 mL) during
48 h. Then, hydrazine monohydrate (8.88 mL, 183 mmol, 10 eq)
was added and the resulting mixture further stirred under reflux
for 48 h. The addition of the resulting colourless solution to
2.2.3.2. Synthesis of Na4(LS)2(H2O)22ꢀ2H2O (C2). A solution of K2LS in
water (100 mg in 2 mL) was acidified to pH 1 using dil. aq. HCl
(1 M). Then, aq. NaOH (10% w/w) was added to reach basic pH
14. Addition of acetone (15 mL) led to the precipitation of a white
powder (72 mg), which was further washed with cold water (5 mL)

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D. Specklin et al. / Polyhedron 100 (2015) 359–372
and THF (15 mL). Among this quantity, 10 mg were solubilized in
water (1 mL) and let to diffusion with acetone. Colourless crys-
talline needles of titled sodium complex were isolated after 4 days.
cilic acid which was simply stirred in MeOH to afford correspond-
ing methyl ester 2 (Scheme 2). The reaction of 2 with hydrazine
monohydrate at ambient temperature led to the 5-sulfosalycilic
hydrazide 3 which was isolated as a white powder after recrystal-
lization in MeOH. Compound 3 was found to be a key entry for the
preparation of both salts of ligands H2LS and H2LAc. K2LS was thus
obtained by a reaction of cyclisation in basic media (KOH) involv-
ing 3 in the presence of carbon disulfide (CS2) and 1,2-dibro-
moethane. Noteworthy, (i) the control of the temperature is
crucial and best yields were obtained at room temperature, and
(ii) similar reactions carried out with other bases, i.e. NaOH and
LiOH, did not lead to target alkaline compounds. Thus, K2LS com-
pound was found to be a key entry also for the preparation of other
alkaline aroylhydrazonates, namely with Li(I), Na(I) and Ba(II)
counter-anions. A typical reaction consisted in successive protona-
tion and deprotonation process, by using diluted aqueous solutions
of HCl and corresponding base respectively. The preparation of CPs
with ligand H2LAc can be achieved using two distinct synthetic
routes. The direct route consisted in the reaction of 3 with target
Li(I), Na(I), K(I) and Ba(II) salts in water followed by the addition
of acetone (excess) which has resulted in species of general for-
mula [Mx(LAc)] (x = 2 for Li, Na and K; x = 1 for Ba). Noteworthy,
the second route, which was attempted to optimize the yields,
proved to be successful as well. In this respect, compound 3 was
reacted with excess hydrazine in refluxing MeOH followed by a
precipitation with THF, which has resulted in the hydrazonium salt
4 in quantitative yield. The addition of selected bases in water has
led to target CPs of Li(I), Na(I), K(I) and Ba(II) ions, whilst the direct
reaction of 4 with acetone led in the immediate precipitation of the
new 5-sulfosalicyloylhydrazono-2-propane pyrazolium salt ([pyr]
[HLAc]) {pyr: 3,5,5-trimethyl-4,5-dihydro-1H-pyrazolium}. This
ligand is also a key entry for the synthesis of the CPs using the
same strategy applied for K2LS, i.e. via successive protonation and
deprotonation process, by using diluted aqueous solutions of HCl
and corresponding base respectively, followed by precipitation
using the solvent acetone.
2.2.3.3. Synthesis of K2(LS)(H2O)2 (C3). A solution of K2LS in water
(100 mg in 2 mL) was recrystallized in acetone/H2O mixture
(50/50), what has resulted, after 3 days, to crystallization of
K2(LS)(H2O)2 as colourless prismatic single crystals.
2.2.3.4. Synthesis of Ba(LS)(H2O)4 (C4). A solution of K2LS in water
(100 mg in 2 mL) was acidified to pH 1 using dil. aq. HCl (1 M).
Then, saturated aq. Ba(OH)2 was added to reach basic pH 14. Addi-
tion of acetone (20 mL) led to the precipitation of a white powder
(80 mg), which was further washed with cold water (5 mL) and
THF (10 mL). Among this quantity, 5 mg were solubilized in water
(1 mL) and let to diffusion with acetone. Colourless crystals of title
barium CP were isolated after 2 days.
2.2.3.5. Synthesis of [Li(LAc)(H2O)2][Li(H2O)4]ꢀH2OꢀOC3H6 (C5). To a
solution of 5-sulfosalicylic hydrazonium salt (100 mg, 0.38 mmol)
in water (1 mL) was added aq. LiOH (1 M, 0.76 mL). Then, acetone
(20 mL) was added, which resulted in the precipitation of a white
powder (95 mg). Among this quantity, 10 mg were solubilized in
water (1 mL) and let to diffusion with acetone. Colourless crys-
talline needles of title lithium CP were isolated after 3 days.
2.2.3.6. Synthesis of Na2(LAc)(H2O)2 (C6). To a solution of 5-sulfosal-
icylic hydrazonium salt (100 mg, 0.38 mmol) in water (1 mL) was
added aq. LiOH (1 M, 0.76 mL). Then, acetone (20 mL) was added,
which resulted in the precipitation of a white powder (97 mg).
Among this quantity, 10 mg were solubilized in water (1 mL) and
let to diffusion with acetone. Colourless crystalline needles of titled
sodium complex were isolated after 3 days.
2.2.3.7. Synthesis of K2(LAc)(H2O) (C7). To a solution of 5-sulfosali-
cylic hydrazonium salt (100 mg, 0.38 mmol) in water (1 mL) was
added aq. KOH (1 M, 0.76 mL). Then, acetone (30 mL) was added,
which resulted in the precipitation of a white powder (101 mg).
Among this quantity, 10 mg were solubilized in water (1 mL) and
let to diffusion with acetone. Colourless crystalline needles of title
potassium complex were isolated after 3 days.
3.2. Crystal structure description (all crystal data, refinement details
and selected bond lengths for all compounds are gathered in
Supplementary materials in Tables X1–XN)
3.2.1. Crystal structure of 5-sulfosalicyloylhydrazono-2-propane
pyrazolium salt ([pyr][HLAc
]
2.2.3.8. Synthesis of Ba(LAc)(H2O)4ꢀH2O (C8). To a solution of 5-sul-
fosalicylic hydrazonium salt (100 mg, 0.38 mmol) in water (1 mL)
was added aq. Ba(OH)2 (0.1 M, 7.6 mL). Then, acetone (20 mL)
was added, which resulted in the precipitation of a white powder
(101 mg). Among this quantity, 10 mg were solubilized in water
(1 mL) and let to diffusion with acetone. Colourless crystals of title
barium CP were isolated after 4 days. 1H NMR (DMSO-d6): d = 7.90
(d, J = 2.4 Hz), 7.26 (dd, J = 8.8 Hz and 2.4 Hz, 1H), 6.21 (d,
J = 8.8 Hz, 1H), 3.73 (s, 3H), 3.29 (s, 3H).
[pyr][HLAc] salt crystallizes in the monoclinic space group P21/
c. The crystal structure clearly shows that both ligand and pyra-
zolium derivatives are organized as finite molecules. Classical intra
molecular hydrogen bonds are observed between the oxygen atom
of the phenol group and nitrogen atom of the hydrazine (N1–
Hꢀ ꢀ ꢀO4, 2.660(3) Å, 134(2)°). Intermolecular hydrogen bonds are
also observed between one oxygen atom of the sulfonate and one
nitrogen atom of the pyrazolium (N4–Hꢀ ꢀ ꢀO1, 2.784(3) Å, 154
(3)°). The packing diagram can be analysed as ligands and pyra-
zolium layers, as pointed out in Fig. 1 (right).
3. Results and discussion
3.2.2. Crystal structure of 5-sulfosalicyloylhydrazono-1,3-dithiolane
3.1. Synthesis
potassium salt (K2LS)
S
The coordination chemistry of both aroylhydrazones H2LS and
H2LAc is unexplored. We thus undertook to use these two new
ligands in the preparation of a collection of CPs with different
dimensionalities. Ten new compounds have been synthesized
and their structures characterized by single crystal X-ray diffrac-
tion. The crystal structure description of all compounds is dis-
cussed below (see Section 3.2). From the synthetic front, 5-
sulfosalicyloylhydrazono-1,3-dithiolane potassium salt K2LS was
synthesized in three steps starting from commercial 5-sulfosaly-
K2L salt crystallizes in the trigonal space group R3 and contains
one molecule in the asymmetric unit. The asymmetric unit consists
of two potassium centres, one organic ligand molecule and two ter-
minal N,N0-DMF molecules (Fig. 2).
ꢀ
Both metal centres – there are two crystallographic positions
for potassium cation K1 and K2 – are coordinated to seven atoms
and exhibit distorted pentagonal bi-pyramidal geometry. K1 cation
is coordinated to the N@N nitrogen (N2) and the C@O oxygen (O1)
atoms of the ligand, the SO3 oxygen (O3, O4) atoms of a symmetry

D. Specklin et al. / Polyhedron 100 (2015) 359–372
363
Fig. 1. Left: ORTEP view of asymmetric unit of [LAc][pyr] salt with partial labelling scheme. The ellipsoids enclose 50% of the electronic density. Dashed lines indicate both
intra and inter molecular hydrogen bonds. Right: selected packing view in the crystallographic (a,b) plane.
Fig. 2. ORTEP views of K2LS(DMF)2 showing the chemical bonding scheme from ligand (A) and potassium cluster (B) point of view. The ellipsoids enclose 50% of the electronic
density. Some hydrogen atoms have been omitted for clarity. Symmetry codes for equivalent positions: a = x, y, ꢁ1 + z; e = y, ꢁx + y, 2 ꢁ z; h = 1/3 ꢁ y, ꢁ1/3 + xꢁy, ꢁ1/3 + z;
o = 2/3 ꢁ x + y, 1/3 ꢁ x, 1/3 + z; p = 2/3 ꢁ x, 1/3 ꢁ y, 4/3 ꢁ z.
related ligand, the SO3 oxygen (O2) atom of another symmetry
related ligand and two oxygen atoms (O6, O7) of DMF solvent
molecules. K2 is coordinated to the phenoxide oxygen (O5) atom
of the ligand, the SO3 oxygen (O2, O3) atoms of a symmetry related
ligand, the SO3 oxygen (O2, O4) atoms of another symmetry related
ligand and one DMF oxygen atom (O7). In total, each ligand coor-
dinates to six different metal centres as displayed in Fig. 2. The
crystal structure of K2LS is stabilized by the formation of a strong
N–Hꢀ ꢀ ꢀO intramolecular hydrogen bond within the ligand between
the protonated nitrogen (N1) and the phenoxide oxygen atom (O5)
(N1–Hꢀ ꢀ ꢀO4, 2.559(3) Å, 152(1)°).
From packing diagram front, this compound can be described as
a 3-D CP with two types of channels, i.e. triangular and hexagonal
with a 2:1 ratio, crossing the structure along the crystallographic c-
axis and partially filled by crystallization DMF molecules (see
Fig. 3), forming thus a potential porous material. Triangular chan-
nels have a diameter of approximately 3 Å and are fully occupied
by solvent DMF molecules coordinating each a potassium atom.
The hexagonal channels have a diameter of approximately 12 Å.
Since six DMF molecules are into the channel, an effective diameter
of 6 Å must thus be considered. This size is notably comparable to
Fig. 3. Packing view of K2LS(DMF)2 along the crystallographic c-axis showing both
the pore size of zeolites materials, for instance. Since the residual
triangular and hexagonal channels.
electron density calculated by PLATON software and the estimation
of the empty space indicate that the channels are occupied statis-
tically by a half molecule of DMF (these disordered solvent mole-
cules have been considered during the refinement), the
unoccupied volume thus represents 40% of total volume of this
structure.
molecule and a total of six water molecules, out of which three
act as terminal ligands, two as bridging ligands and one is present
in the lattice (Fig. 4). Li1 cation is coordinated to five oxygen atoms
and exhibits a distorted square pyramidal geometry. The basal
plane consists of two oxygen atoms (O7, O8) from water molecules,
as well as the N@N nitrogen (N2) and the C@O oxygen (O5) atom of
the ligand which coordinates to the metal centre in a bidentate
fashion (Scheme 1A). An oxygen atom (O6) from a third water
molecule occupies the apical position. While there are two Li
atoms present in the structure, only Li1 is coordinated to the
3.2.3. Crystal structure of Li2(LS)(H2O)5ꢀH2O (C1)
ꢀ
Compound C1 crystallizes in the triclinic space group P1 and
contains one molecule in the asymmetric unit. The crystal struc-
ture of C1 reveals the formation of finite compound. The asymmet-
ric unit consists of two lithium centres, one organic ligand

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D. Specklin et al. / Polyhedron 100 (2015) 359–372
the formation of a neutral two dimensional (2D) coordination poly-
mer. The unit consists of four sodium metallic centres, two organic
ligand molecules and twelve water molecules, out of which eight
act as terminal ligands, two as bridging ligands and two are present
in the lattice. All Na ions are coordinated to the organic ligand. Na1
centre is coordinated to five atoms and exhibits a slightly distorted
square pyramidal geometry (s = 0.15).[32] The basal plane consists
of the N@N nitrogen atom (N2) and the C@O oxygen atom (O1) of
one ligand molecule, as well as two oxygen atoms (O15, O20) from
terminal water molecules. One oxygen atom (O14) from a bridging
water molecule occupies the apical position. Na2 ion is also coor-
dinated to five atoms in
a square pyramidal environment
(s
= 0.04) [32]. The basal plane consists of two oxygen atoms
(O16, O17) from terminal water molecules and the N@N nitrogen
(N4) and C@O oxygen (O6) atoms of another ligand molecule.
The apical position is occupied by an oxygen atom (O19) from a
bridging water molecule. Na3 ion is coordinated to six atoms and
exhibits a distorted octahedral geometry. Four water oxygen atoms
(O11, O12, O12, O19) occupy the equatorial positions of the octa-
hedron, while one SO3 oxygen (O3) and one water oxygen (O20)
atoms occupy the axis. Each of these two centres is coordinated
to two oxygen atoms from terminal water molecules (O11, O12,
O13 and O18 respectively), one bridging water oxygen atom
(O19 and O14 respectively) and one SO3 oxygen atom (O3 and
O7 respectively). Finally, Na4 centre is coordinated to five atoms
Fig. 4. ORTEP view of compound C1 with partial labelling scheme. The ellipsoids
enclose 50% of the electronic density. Solvent H2O molecule (O11) is not
represented for clarity.
ligand. Li2 cation is coordinated to four water molecules (atoms
O7, O8, O9 and O10) possessing a distorted tetrahedral geometry.
The distance between Li1 and Li2 is 2.959(5) Å, while the bridging
Li1ꢁO8ꢁLi2 and Li1ꢁO7ꢁLi2 bond angles are 92.69(18) and 91.01
(17)° respectively. The crystal structure of C1 is stabilized by strong
intermolecular hydrogen bonds, which involve the oxygen atoms
of all six water molecules as donors (O6 up to O11). Each of these
atoms acts as a donor in two hydrogen bonds for a total of twelve
strong intermolecular hydrogen bonds (see Table X6 in Supple-
mentary materials and Fig. 5). The atoms involved as acceptors in
these bonds are the three oxygen atoms of the sulfonate group
SO3 (O1, O2, O3), the phenoxide and carbonyl group (C@O) oxygen
atoms (O4 and O5) and the oxygen atoms of three of the four
non-bridging water molecules (O6, O10 and O11). The structure
and exhibits a distorted trigonal bipyramidal geometry (s = 0.65)
[32]. The basal plane consists of one SO3 oxygen atom (O7) and
two water oxygen atoms (O14 and O13), while the apical positions
are occupied by two additional water oxygen atoms (O18 and
O13). As a result, the ligand becomes tridentate (see coordination
mode in Scheme 4). The distances between the bridged metal cen-
tres Na1-Na4 and Na2-Na3 is 4.192(17) Å and 4.273(16) Å, respec-
tively. Bridging Na1ꢁO14ꢁNa4 and Na2ꢁO19ꢁNa3 bond angles
are 120.54(10)° and 127.34(10)° respectively. The structure of
compound C2 propagates in two directions through the bridging
ligand forming layers along the b0c plane axis (Fig. 6). The crystal
structure of C2 is further stabilized by strong intermolecular
hydrogen bonds, which involve the oxygen atoms of all twelve
water molecules as donors (O11-to-O22). Each of these atoms acts
as a donor in two hydrogen bonds for a total of 24 intermolecular
hydrogen bonds. The atoms involved as acceptors in these bonds
are the oxygen atoms of the SO3 group, the C@O group oxygen
atoms together with the oxygen atoms of other water molecules.
is further stabilized by the formation of
intramolecular hydrogen bond within the ligand between the
protonated nitrogen (N1) and the phenoxide oxygen atom (O4).
a
strong N–Hꢀ ꢀ ꢀO
3.2.4. Crystal structure of Na4(LS)2(H2O)22ꢀ2H2O (C2)
ꢀ
Compound C2 crystallizes in the triclinic space group P1 and
contains one molecule in the asymmetric unit. X-ray data reveals
Fig. 5. Packing diagram of compound C1 into both crystallographic (b,c) and (a,b) planes.

D. Specklin et al. / Polyhedron 100 (2015) 359–372
365
Scheme 4. Coordination modes of the metals to the ligands LS (modes A–D, I) and LAc (modes E–H).
Fig. 6. ORTEP views of the two parts of compound C2 with partial labelling scheme. The ellipsoids enclose 50% of the electronic density. Solvent H2O molecules (O21 and O22)
are not represented for clarity. Dashed lines indicate selected hydrogen bonds. Symmetry for equivalent positions: a = 2 ꢁ x, 1 ꢁ y, ꢁz; b = 2 ꢁ x, 2 ꢁ y, 1 ꢁ z; c = 2ꢁx, 3 ꢁ y,
1ꢁz.
The structure C2 is further stabilized by the formation of a strong
N–Hꢀ ꢀ ꢀO intramolecular hydrogen bond within each ligand,
between the protonated nitrogen and the phenoxide oxygen atoms
(see Fig. 7 and Table X8).
Precisely, K1 ion is coordinated to the SO3 oxygen atoms (O2, O4)
of the ligand, the SO3 oxygen atoms (O3, O4) of a symmetry related
ligand, the SO3 oxygen atom (O4) of a third symmetry related
ligand, the C@O oxygen atom (O5) of another symmetry related
ligand and a water molecule oxygen atom (O6). K2 cation is coor-
dinated to a total of six atoms and exhibits a highly distorted octa-
hedral geometry. In detail, K2 centre is connected to the SO3
oxygen (O2) atom of the ligand, two SO3 oxygen (O3, O3) atoms
of symmetry related ligands and three water molecule oxygen
atoms (O7). Despite the increase of the radii, the structure of C3
propagates, as in compound C2, in two directions (see Fig. 9)
through the bridging ligand forming layers along the b0c plane axis
3.2.5. Crystal structure of K2LS(H2O)2 (C3)
Compound C3 crystallizes in the monoclinic space group P21/c
and contains one molecule in the asymmetric unit. The unit con-
sists of two potassium centres, one organic ligand molecule and
two terminal water molecules (Fig. 8). In this compound, the ligand
coordinates in a tetradentate fashion. K1 centre is coordinated to
seven atoms in a distorted pentagonal bipyramidal environment.

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D. Specklin et al. / Polyhedron 100 (2015) 359–372
and further stabilized by strong intermolecular hydrogen bonds, in
which the water molecule oxygen atom (O6) acts as a donor. The
N@N group nitrogen atom (N2) acts as an acceptor. The structure
is further stabilized by the formation of a strong O–Hꢀ ꢀ ꢀO (O6-
H2Wꢀ ꢀ ꢀO5) and a strong N–Hꢀ ꢀ ꢀO (N1-H1Nꢀ ꢀ ꢀO1) intramolecular
hydrogen bonds within the ligand (see SI, Tables X9 and X10, for
details) (Table 1).
3.2.6. Crystal structure of Ba(LS)(H2O)4 (C4)
Compound C4 crystallizes in the monoclinic space group P21/c
and contains one molecule in the asymmetric unit. The unit con-
sists of one barium ion centre, one organic ligand molecule and
four terminal water molecules (Fig. 10). Each ligand is coordinated
to four different metal centres as presented in Scheme 4. Ba1 ion is
coordinated to a total of eight atoms and exhibits a distorted
square antiprismatic geometry. One square consists of the N@N
nitrogen (N1) atom of the ligand and the phenoxide oxygen atom
(O2) from a symmetry related ligand molecule, as well as two oxy-
gen atoms (O7, O9) from water molecules. The mean deviation of
this plane is 0.123 Å. The second square contains the C@O oxygen
Fig. 7. Packing diagram of compound C2 into crystallographic (b,c) plane.
Fig. 8. (A) ORTEP view of compound C3 with partial labelling scheme. The ellipsoids enclose 50% of the electronic density. (B) Ball and stick view of potassium atoms
coordination. Dashed lines indicate intramolecular hydrogen bonds. Symmetry for equivalent positions a = x, ꢁ1 + y, z; b = x, 1 + y, z; c = 2 ꢁ x, ꢁ1/2 + y, 3/2 ꢁ z; d = 2 ꢁ x, 1/2
+ y, 3/2 ꢁ z; f = 2 ꢁ x, 1 ꢁ y, 1 ꢁ z.
Fig. 9. Packing diagram of compound C3 in both (a,c) and (b,c) crystallographic planes.

D. Specklin et al. / Polyhedron 100 (2015) 359–372
367
Table 1
(O1) atom of the ligand and the SO3 oxygen (O4) atom from a sym-
metry related ligand molecule, as well as two oxygen atoms (O6,
O8) from water molecules. The mean deviation of this plane is
0.253 Å. Plane centroid to plane centroid distance was measured
as 2.7204(8) Å. The angle between the mean planes is 7.39(3)°,
with the metal centre being located at 1.149(2) Å from the first
plane and 1.561(2) Å from the second one. The twist angle between
the two mean planes is 52.7(2)°. Despite the further increase of the
ionic radii of the metal centre, no influence in the dimensionality of
the final product is observed. Therefore, as complexes C2 and C3,
compound C4 propagates along the b0c plane axis (Fig. 11). The
crystal structure of C4 is stabilized by strong intermolecular hydro-
gen bonds, in which the oxygen atoms of all four water molecules
are donors (O6–O9). Each of these atoms acts as a donor in two
hydrogen bonds for a total of eight strong intermolecular hydrogen
bonds. The atoms involved as acceptors in these bonds are the C@O
and phenoxide group oxygen atoms (O1, O2), two of the three oxy-
gen atoms of the SO3 (O3, O5) and the oxygen atoms of two water
molecules (O6, O9). The structure is further stabilized by the for-
mation of a strong N–Hꢀ ꢀ ꢀO intramolecular hydrogen bond within
Global reaction conditions for the synthesis of C1–C8 and K2LS_DMF.
Ligand Metal Compound Dimensionality Solvent Topology
H2LS
H2LS
H2LS
Li
Na
K
C1
C2
C3
0D
2D
2D
H2O
H2O
H2O
–
3,3,4L24
(43)(45.6)
(411.610
)
H2LS
Ba
Li
Na
C4
C5
C6
2D
0D
3D
H2O
H2O
H2O
fes
–
H2LAc
H2LAc
(43.83)(45.6)
(412.69)
H2LAc
K
C7
3D
H2O
(43)2(48.62)2
(411.64) (413.62)
(413.613.82)2
/
(6.92) (32.4.6.7.8)
(32.4.92.10)
(32.44.6.7.82)
SP 1-periodic
network (4,4)
(0,2)
H2LAc
H2LS
Ba
K
C8
1D
3D
H2O
K2LS_DMF
DMF
3,6T18
Fig. 10. (A) ORTEP view of compound C4 with partial labelling scheme. The ellipsoids enclose 50% of the electronic density. (B) Ball and stick view of barium ion coordination.
Dashed lines indicate intramolecular hydrogen bonds. Symmetry for equivalent positions: b = 1 ꢁ x, ꢁy, 2 ꢁ z; c = x, 1/2 ꢁ y, ꢁ1/2 + z; d = x, 1/2 ꢁ y, 1/2 + z.
Fig. 11. Packing diagram of compound C4 in both (a,c) and (b,c) crystallographic planes.

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D. Specklin et al. / Polyhedron 100 (2015) 359–372
the ligand between the protonated nitrogen (N2) and the phenox-
ide oxygen atom (O2).
3.2.7. Crystal structure of [Li(LAc)(H2O)2][Li(H2O)4]ꢀH2OꢀOC3H6 (C5)
ꢀ
Compound C5 crystallizes in the triclinic space group P1 and
contains one molecule in the asymmetric unit and is a finite mole-
cule. The unit consists of two lithium centres, one organic ligand
molecule, one lattice acetone molecule and a total of seven water
molecules, out of which six act as terminal ligands and one is pre-
sent in the lattice (Fig. 12). While there are two Li atoms present in
the structure, only Li1 ion is coordinated to the organic ligand,
through the N@N nitrogen (N2) and the C@O oxygen (O1) atoms
(Scheme 4) and to two other oxygen atoms (O7, O8) from water
molecules, thus displaying a total coordination number of four
and a distorted tetrahedral geometry. Li2 centre is coordinated to
four water molecules through oxygen atoms O9, O10, O11 and
O13 in
a
distorted tetrahedral environment. The Owater
ꢁ Li2 ꢁ Owater angles range from 106.9(2) to 112.4(2)°. The crystal
structure of complex C5 is stabilized by strong intermolecular
hydrogen bonds, which involve the oxygen atoms of all seven
Fig. 12. ORTEP view of compound C5 with partial labelling scheme. The ellipsoids
enclose 50% of the electronic density.
Fig. 13. Packing diagram of compound C5 in both (a,c) and (b,c) crystallographic planes.
Fig. 14. (A) ORTEP view of compound C6 with partial labelling scheme. The ellipsoids enclose 50% of the electronic density. (B) Ball and stick view of sodium ion coordination.
Dashed lines indicate intramolecular hydrogen bonds. Symmetry for equivalent positions: a = 1ꢁx, ꢁ1/2 + y, 1/2 ꢁ z; b = 1 ꢁ x, 1/2 + y, 1/2 ꢁ z; c = ꢁx, 1 ꢁ y, 1 ꢁ z; d = 1ꢁx,
1 ꢁ y, 1 ꢁ z; e = x, 3/2 ꢁ y, ꢁ1/2 + z; f = x, 3/2 ꢁ y, 1/2 + z.

D. Specklin et al. / Polyhedron 100 (2015) 359–372
369
water molecules as donors (O7–O13). Each of these atoms acts as a
donor in two hydrogen bonds for a total of 14 strong intermolecu-
lar hydrogen bonds. The structure is further stabilized by the for-
phenoxide oxygen atom (O4) from a fourth ligand molecule occu-
pies the apical position. Na2 centre is coordinated to six atoms in a
severely distorted octahedral environment. The basal plane is
determined by the SO3 oxygen (O1) atom of the ligand, the oxygen
atom (O4) from a second ligand and two oxygen atoms from water
molecules (O6). The two apical positions are occupied by a water
oxygen atom (O7) and a SO3 oxygen atom (O2). The distance
between the two Na centres was found to be 3.360(12) Å. The crys-
tal structure of compound C6 is stabilized by strong intermolecular
hydrogen bonds, in which the oxygen atoms of the two water
molecules act as donors (O6 and O7) for a total of three strong
intermolecular hydrogen bonds. The atoms involved as acceptors
in these bonds are the three oxygen atoms of the SO3 group (O2,
O3) and the C@O group oxygen atom (O5). The structure is further
stabilized by the formation of a strong N–Hꢀ ꢀ ꢀO intramolecular
hydrogen bond within the ligand between the protonated nitrogen
(N1) and the phenoxide oxygen (O4) atoms. A packing diagram is
given in Fig. 15.
mation of
a
strong N–Hꢀ ꢀ ꢀO intramolecular hydrogen bond
within the ligand between the protonated nitrogen (N1) and the
phenoxide oxygen atom (O5). A packing diagram is given in Fig. 13.
3.2.8. Crystal structure of Na2(LAc)(H2O)2 (C6)
Compound C6 crystallizes in the monoclinic space group P21/c
and contains one molecule in the asymmetric unit and forms a
3D coordination polymer. The unit consists of two sodium centres,
one organic ligand molecule and two coordinated water molecules
(Fig. 14). Each ligand is ligated to six different metal centres as
highlighted in Scheme 4. Na1 cation is coordinated to a total of five
atoms and exhibits a square pyramidal geometry (s = 0.04) [32].
The basal plane consists of the SO3 oxygen (O1) atom of the ligand,
the N@N nitrogen and the C@O oxygen atoms (N2, O5) of a second
ligand and a SO3 oxygen (O3) atom of a third ligand molecule. A
3.2.9. Crystal structure of K2(LAc)(H2O) (C7)
Compound C7 crystallizes in the monoclinic space group C2/c
and contains one molecule in the asymmetric unit. The unit con-
sists of three potassium centres, one organic ligand molecule and
one coordinating water molecule that acts as a terminal ligand.
K1 ion is coordinated to six atoms and exhibits a distorted octahe-
dral geometry. The apical positions are occupied by both one phe-
noxide oxygen (O4) atom and one water molecule oxygen (O6)
atom. The basal plane consists of four oxygen atoms that derive
from different ligand molecules (O4, O1, O1) and the coordinating
water molecule (O6). K2 centre is coordinated to a total of six
atoms and also exhibits a distorted octahedral geometry. The api-
cal positions are occupied by one phenoxide oxygen (O4) atom and
one water molecule oxygen atom (O6). The basal plane consists of
the N@N nitrogen group atom (N2) and the C@O group oxygen
atom (O5) of one ligand, as well as two SO3 oxygen atoms which
derive from different ligand molecules (O1, O3). K3 cation is coor-
dinated to a total of eight atoms and exhibits a distorted square
antiprismatic geometry. One plane consists of the N@N nitrogen
(N2) and the C@O oxygen (O5) atoms of two ligated molecules.
The mean deviation of this plane is 0.359 Å. The second plane con-
sists of two SO3 oxygen (O2, O2) and two water oxygen atoms (O6,
O6) from two different ligand molecules. The mean deviation of
this plane is 0.269 Å. Plane centroid to plane centroid distance
Fig. 15. Packing diagram of compound C6 in (b,c) crystallographic plane.
Fig. 16. (A) ORTEP view of compound C7 with partial labelling scheme. The ellipsoids enclose 50% of the electronic density. (B) Selected part of potassium ions coordination.
Dashed lines indicate intramolecular hydrogen bonds. Symmetry for equivalent positions: a = 1 ꢁ x, y, 3/2 ꢁ z; b = 1 ꢁ x, 1 ꢁ y, 1 ꢁ z; c = x, 1 ꢁ y, ꢁ1/2 + z; f = 1/2 ꢁ x, ꢁ1/2 + y,
1/2 ꢁ z; h = 1/2 ꢁ x, 1/2 ꢁ y, 1 ꢁ z; i = 1/2 ꢁ x, 3/2 ꢁ y, 1 ꢁ z; k = ꢁ1/2 + x, 3/2 ꢁ y, ꢁ1/2 + z.

370
D. Specklin et al. / Polyhedron 100 (2015) 359–372
was measured at 3.617(2) Å. The planes are almost parallel to each
other, with K3 ion being located almost at the centre, i.e. 1.814(6) Å
from the first plane and 1.803(6) Å from the second one. Each
ligand is coordinated to a total of eight different metal centres as
presented in Scheme 4. As C6, compound C7 extends to three
dimensions via the bridging ligand. The crystal structure of C7 is
stabilized by two strong intermolecular hydrogen bonds, in which
the O6 water molecule oxygen atom acts as donor. The atoms
involved as acceptors in these bonds are the SO3 oxygen atoms
(O2, O3). The structure is further stabilized by the formation of a
strong N–Hꢀ ꢀ ꢀO intramolecular hydrogen bond within the ligand
between the protonated nitrogen (N1) and the phenoxide oxygen
atom (O4). A packing view is given Fig. 17.
deviation of this plane is 0.405 Å. Plane centroid to plane centroid
distance was measured at 3.141(2) Å. The angle between the mean
planes is 12.83(9)°, with the metal centre being located at 1.668(5)
Å from the first plane and 1.446(7) Å from the second. The twist
angle between the two mean planes is 118.8(10)°. In total, each
ligand is coordinated to (a total of) three different metal centres
as presented in Scheme 4. Despite the increase of the radii of the
metal centre, in comparison with C6 and C7, complex C8 forms
one dimensional (1D) chain. The crystal structure of C8 is stabilized
by strong intermolecular hydrogen bonds, in which the oxygen
atoms of all five water molecules are donors (O6 up to O10). Each
of these atoms acts as a donor in two hydrogen bonds for a total of
10 strong intermolecular hydrogen bonds. The atoms involved as
acceptors in these bonds are the phenoxide and C@O group oxygen
atoms (O4, O5), the three oxygen atoms of the SO3 (O1, O2, O3) and
the oxygen atom of the lattice water molecule (O10). The structure
3.2.10. Crystal structure of Ba(LAc)(H2O)4ꢀH2O (C8)
ꢀ
Compound C8 crystallizes in the triclinic space group P1 and
is further stabilized by the formation of
a
strong N–Hꢀ ꢀ ꢀO
contains one molecule in the asymmetric unit. The unit consists
of one barium centre, one organic ligand molecule and a total of
five water molecules, out of which four act as terminal ligands,
and one is present in the lattice. Ba1 centre is coordinated to a total
of eight atoms and exhibits a highly distorted square antiprismatic
geometry. One square consists of the N@N nitrogen (N2) and the
C@O oxygen (O5) atoms of the ligand, as well as the phenoxide
oxygen (O4) atom from a symmetry related ligand molecule and
an oxygen atom of a water molecule (O9). The mean deviation of
this plane is 0.237 Å. The second square contains the SO3 oxygen
(O3) atom from a symmetry related ligand molecule, as well as
three oxygen atoms (O6, O7, O8) from water molecules. The mean
intramolecular hydrogen bond within the ligand between the pro-
tonated nitrogen (N2) and the phenoxide oxygen atom (O4). The
parameters of these hydrogen bonds are listed in Supplementary
materials section (Fig. 16).
3.3. Topological features
A plethora of hydrogen bonds can be found in these compounds.
Therefore, the topological representation of compounds C2–C8 and
K2LS_DMF has been performed taking into account only the coor-
dination bonds. It is worth noting that the statistics on underlying
Fig. 17. Packing diagrams of compound C7 in both (a,b) and (a,c) crystallographic planes.
Fig. 18. (A) ORTEP view of compound C8 with partial labelling scheme. The ellipsoids enclose 50% of the electronic density. (B) Ball and stick view of barium ion coordination.
Dashed lines indicate intramolecular hydrogen bonds. Symmetry for equivalent positions: a = ꢁ1 + x, 1 + y, z; c = ꢁx, 1 – y, ꢁz.

D. Specklin et al. / Polyhedron 100 (2015) 359–372
371
Fig. 19. Selected part of the packing diagram of compound C8 in (a,b) crystallographic plane.
Fig. 20. (a) 3,3,4L24 topology found in C2, (b) (43)(45.6)(411.610) topology, K(I) (blue), Ligand (pink) found in C3, (c) fes, Ba(II) (yellow), Ligand (pink) found in C4, (d) (43.83)
(45.6)(412.69) Na(I) (blue) ligand (pink) found in C6, (e) Five (3,5,6,6,8) nodal network with Point Symbol (43)2(48.62)2(411.64)(413.62)(413.613.82)2 found in C7, (f) SP 1periodic
network (4,4)(0,2) found in C8, (g) 3,6T18, K(I) blue, ligand (pink) found in K2LS_DMF. (Colour online.)
net do not include alkaline metals [33] and thus as it can be
expected unseen topologies can be identified in the present work.
The topological representation of the 2D network found in C2 is
shown in Fig. 20(a). A trinodal (3,3,4) network is constructed by
considering three Na(I) metallic centres as nodes. Topological anal-
ysis of this network reveals that it possesses 3,3,4L24 topology
[34]. Interestingly, a survey in the TOPOS database shows that
there are only two examples [35,36] of 3,3,4L24 topology and that
compound C2 is notably the first structure containing Na(I) with
such topology. The topological analysis for compound C3 has been
performed using a simple analysis which resulted to the same net-
work as well as with the cluster analysis. The topological represen-
tation of the 2D net found in C3 is shown in Fig. 20(b). A trinodal
(3,4,7) network with stoichiometry (3-c)(4-c)(7-c) is constructed
by considering each K(I) centre and each ligand as a node. Topolog-
ical analysis of this network reveals that it possesses an unseen
topology with Point Symbol (43)(45.6)(411.610). Despite the higher
radii of Ba(II), in comparison with Na(I) and K(I) in C2 and C3
respectively, compound C4 forms a 2D network. The topological
interpretation of C4 reveals a uninodal three connected network

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D. Specklin et al. / Polyhedron 100 (2015) 359–372
possessing fes topology. Each organic ligand and Ba(II) units can be
considered as a node to form this network, cf. Fig. 20(c). As
described above, compound C6 forms a 3D coordination polymer.
The topological evaluation of the 3D network found in C6 is as
shown in Fig. 20(d). A trinodal (4,4,7) network is formed by consid-
ering two Na(I) centres (blue) and each ligand (pink) as a node.
Analysis of this network reveals that it possesses an unseen topol-
ogy with Point Symbol (43.83)(45.6)(412.69). The 3D network found
in compound C7, analysed utilizing a simple methodology, corre-
sponds to a five (3,5,6,6,8) nodal network with unseen topology
and Point Symbol (43)2(48.62)2 (411.64) (413.62)(413.613.82)2 Fig 20
(e). Compound C8 is a 1D coordination polymer possessing an
uninodal three connected network with Point Symbol (42.6) cate-
gorized as: SP 1-periodic network (4,4)(0,2) Fig. 20(f). Finally, the
porous structure of compound K2LS_DMF contains a well-defined
K4(SO3)2 cluster that can be considered as a six connected Second-
ary Building Unit (SBU) and the ligand can be considered as a three
connected node. The 6-c SBU is connected to the ligands via O (4ꢂ)
and S (2ꢂ). The resulting net is binodal (3,6) having a topological
type 3,6T18. cf. Fig 20(g). According to TOPOS database this net-
work has been seen in eight compounds (COKMOG, COKNIB, COK-
QAW, DOKDEN, LENKIA, OGAXUR, OGECOU) (Figs. 18 and 19).
Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax: (+44) 1223-
336-033; or e-mail: deposit@ccdc.cam.ac.uk.
Supplementary data associated with this article can be found, in
the online version, at http://dx.doi.org/10.1016/j.poly.2015.08.013.
References
[1] N.H. Alsmail, M. Suyetin, Y. Yan, R. Cabot, C.P. Krap, J. Lü, et al., Chem. Eur. J. 20
(2014) 7317.
[2] T. Min, B. Zheng, J. Bai, R. Sun, Y. Li, Z. Zhang, CrystEngComm 12 (2010) 70.
[3] L. Qin, W.-N. Zhao, G.-J. Yu, L.-P. Xu, L. Han, Inorg. Chem. Commun. 34 (2013)
47.
[4] C.N. Morrison, A.K. Powell, G.E. Kostakis, Cryst. Growth Des. 11 (2011) 3653.
[5] J. Liu, J. Wu, Z. Jia, H. Chen, C. Daiguebonne, O. Guillou, et al., Dalton Trans. 43
(2014) 17265.
[6] S.S.P. Dias, M.V. Kirillova, V. André, J. Kłak, A.M. Kirillov, Inorg. Chem. 54 (2015)
5204.
[7] G. Peng, L. Ma, J. Cai, L. Liang, H. Deng, G.E. Kostakis, Cryst. Growth Des. 11
(2011) 2485.
[8] M. Wu, F. Jiang, X. Kong, D. Yuan, L. Long, S.A. Al-Thabaiti, et al., Chem. Sci. 4
(2013) 3104.
[9] Z. Majeed, K.C. Mondal, G.E. Kostakis, Y. Lan, C.E. Anson, A.K. Powell, Chem.
Commun. 46 (2010) 2551.
[10] C. Janiak, J.K. Vieth, New J. Chem. 34 (2010) 2366.
[11] L. Han, L. Qin, L. Xu, Y. Zhou, J. Sun, X. Zou, Chem. Commun. 49 (2013) 406.
[12] I. Imaz, M. Rubio-Martínez, J. An, I. Solé-Font, N.L. Rosi, D. Maspoch, Chem.
Commun. 47 (2011) 7287.
[13] K.C. Mondal, G.E. Kostakis, Y. Lan, C.E. Anson, A.K. Powell, Inorg. Chem. 48
(2009) 9205.
[14] M. Kurmoo, Chem. Soc. Rev. 38 (2009) 1353.
[15] B. Joarder, A.V. Desai, P. Samanta, S. Mukherjee, S.K. Ghosh, Chem. Eur. J. 21
(2015) 965.
4. Conclusion
We present herein a systematic investigation on the coordina-
tion abilities of two new aroylhydrazonate ligands, i.e. H2LS and
H2LAc, along with alkali Li(I), Na(I), K(I) and Ba(II) metal ions. The
dimensionality of the final product is independent of the ionic radii
and strongly depends on the ligand substitution. Noteworthy,
using the solvent DMF instead of H2O results in the formation of
a highly porous 3D material, i.e. K2LS_DMF, with 40% unoccupied
volume. Having all this knowledge in mind and being aware that
structural motifs for such kinds of aroylhydrazonate ligands can
be readily reproducible, our efforts are now dedicated to the prepa-
ration of porous CPs using such ligand together with the assess-
ment of their absorption properties on small molecules such as
CO2 and N2.
[16] S.S. Nagarkar, A.V. Desai, S.K. Ghosh, Chem. Commun. 50 (2014) 8915.
[17] J.B. DeCoste, M.H. Weston, P.E. Fuller, T.M. Tovar, G.W. Peterson, M.D. LeVan,
et al., Angew. Chem., Int. Ed. 53 (2014) 14092.
[18] B. Manna, A.V. Desai, N. Kumar, A. Karmakar, S.K. Ghosh, CrystEngComm
(2015), http://dx.doi.org/10.1039/C5CE00139K.
[19] P.M. Usov, C. Fabian, D.M. D’Alessandro, Chem. Commun. 48 (2012) 3945.
[20] L. Sun, C.H. Hendon, M.A. Minier, A. Walsh, M. Dinca, J. Am. Chem. Soc. 137
(2015) 6164.
[21] H.-C. Zhou, J.R. Long, O.M. Yaghi, Chem. Rev. 112 (2012) 673.
[22] S. Furukawa, J. Reboul, S. Diring, K. Sumida, S. Kitagawa, Chem. Soc. Rev. 43
(2014) 5700.
[23] M.V. Angelusiu, G.L. Almajan, T. Rosu, M. Negoiu, E.-R. Almajan, J. Roy, Eur. J.
Med. Chem. 44 (2009) 3323.
[24] M.V. Angelusiu, S.-F. Barbuceanu, C. Draghici, G.L. Almajan, Eur. J. Med. Chem.
45 (2010) 2055.
[25] M.R. Maurya, S. Agarwal, M. Abid, A. Azam, C. Bader, M. Ebel, et al., Dalton
Trans. (2006) 937.
[26] D.K. Johnson, T.B. Murphy, N.J. Rose, W.H. Goodwin, L. Pickart, Inorganica
Chim. Acta 67 (1982) 159.
[27] T.B. Chaston, D.B. Lovejoy, R.N. Watts, D.R. Richardson, Clin. Cancer Res. 9
(2003) 402.
Acknowledgments
This work was supported by the Centre National de la
Recherche Scientifique (CNRS). S.M. and R.W. thank the Ministère
de la Recherche (FRANCE) for PhD financial support of D.S. A. Haze-
mann from the IUT Robert Schuman (Unistra) is gratefully thanked
for the elemental analysis. Dr. M. Kurmoo is gratefully acknowl-
edged for scientific discussions and orientations.
[28] G. Link, P. Ponka, A.M. Konijn, W. Breuer, Z.I. Cabantchik, C. Hershko, Blood 101
(2003) 4172.
[29] S. Rollas, S.G. Küçükgüzel, Molecules 12 (2007) 1910.
´
[30] D. Matoga, J. Szklarzewicz, R. Grybos, K. Kurpiewska, W. Nitek, Inorg. Chem. 50
(2011) 3501.
[31] C. Bouchameni, C. Beghidja, A. Beghidja, P. Rabu, R. Welter, Polyhedron 30
(2011) 1774.
[32] A.W. Addison, T.N. Rao, J. Reedijk, J. Vanrijn, G.C. Verschoor, J. Chem. Soc. Trans.
(1984) 1349.
[33] E.V. Alexandrov, V.A. Blatov, A.V. Kochetkov, D.M. Proserpio, CrystEngComm
13 (2011) 3947.
Appendix A. Supplementary data
[34] V.A. Blatov, A.P. Shevchenko, D.M. Proserpio, Cryst. Growth Des. 14 (2014)
3576.
[35] M.M. Monchak, A.V. Pavlyuk, V.V. Kinzhibalo, M.G. Mys’kiv, Russ. J. Coord.
Chem. 35 (2009) 405.
[36] S. Naiya, C. Biswas, M.G.B. Drew, C.J. Gómez-García, J.M. Clemente-Juan, A.
Ghosh, Inorg. Chem. 49 (2010) 6616.
CCDC 1407586–1407595 contains the supplementary crystallo-
graphic data for C1–C8, [pyr][HLAc] and K2LS_DMF. These data can
be obtained free of charge via http://www.ccdc.cam.ac.uk/conts/
retrieving.html, or from the Cambridge Crystallographic Data