A family of 2D and 3D coordination polymers involving a trigonal tritopic linker

Article abstract of DOI:10.1039/c2dt12072k

Five new coordination polymers, namely, [Zn₂(H ₂O)₂(BBC)](NO₃)(DEF)₆ (DUT-40), [Zn₃(H₂O)₃(BBC)₂] (DUT-41), [(C ₂H₅)₂NH

Full text of DOI:10.1039/c2dt12072k

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PAPER
A family of 2D and 3D coordination polymers involving a trigonal tritopic
linker†
Ines Maria Hauptvogel,a Volodymyr Bon,a Ronny Grünker,a Igor A. Baburin,b Irena Senkovska,a
Uwe Muellerc and Stefan Kaskel*a
Received 1st November 2011, Accepted 27th December 2011
DOI: 10.1039/c2dt12072k
Five new coordination polymers, namely, [Zn2(H2O)2(BBC)](NO3)(DEF)6 (DUT-40),
[Zn3(H2O)3(BBC)2] (DUT-41), [(C2H5)2NH2][Zn2(BBC)(TDC)](DEF)6(H2O)7 (DUT-42),
[Zn10(BBC)5(BPDC)2(H2O)10](NO3)(DEF)28(H2O)8 (DUT-43), and [Co2(BBC)(NO3)(DEF)2(H2O)]
(DEF)6(H2O) (DUT-44), where BBC – 4,4′,4′′-(benzene-1,3,5-triyl-tris(benzene-4,1-diyl))tribenzoate,
TDC – 2,5-thiophenedicarboxylate, BPDC – 4,4′-biphenyldicarboxylate, DEF – N,N-diethylformamide,
were obtained under solvothermal conditions and structurally characterized. It has been shown that
compounds DUT-40, DUT-41 and DUT-44 exhibit 2D layered structures with large hexagonal channels.
Utilization of additional angular dicarboxylic TDC linker led to the formation of the DUT-42 compound
with the structure consisting of three interpenetrated 3D networks. Using the linear co-linker dicarboxylic
BPDC, DUT-43 was obtained which forms a complicated 3D architecture arising from the polycatenation
of triple-layered 2D building units and 2D single layer units. The pore accessibility of the synthesized
compounds in the liquid phase was proved by the adsorption of dye molecules.
for a fixed chemical composition, structural diversity of resulting
Introduction
coordination polymers is nearly indefinite.5 The study of such
Porous coordination polymers (PCPs) also referred to as metal–
organic frameworks (MOFs), have stayed on the cutting edge at
the focus of research for the last two decades.1 The wide field of
application of such materials ranges from gas storage and gas
separation to heterogeneous asymmetric catalysis,2 and separ-
ation of enantiomers.3 The great success of MOFs in these appli-
cation fields can be attributed to their outstanding porosity
(specific area up to 6240 m2 g−1)4 and modular building-blocks
concept.
isomers can be helpful to understand the influence of different
synthesis parameters on the resulting structure and to achieve
certain control over the composition, structure, net topology and
eventually the properties of new compounds. Up to now, such
control still remains a challenge in the synthesis of coordination
polymers.
The use of tritopic linkers turns out to be very successful in
the construction of highly porous MOFs. The most investigated
and even commercially available MOF named HKUST-1
(Cu3(BTC)2) is composed of Cu paddle-wheel clusters and a
small aromatic tritopic linker (BTC = benzene-1,3,5-tricarboxy-
late). The robust and highly porous framework has the tbo topo-
logy. The use of elongated tritopic BTB linker (BTB =
benzene-1,3,5-tribenzoate) in combination with the same sec-
ondary building unit (SBU) leads to the three different struc-
tures, namely DUT-346 (or MOF-143)7 (pto net), MOF-148
(interwoven pto net), and DUT-336 (interwoven tbo net). Utiliz-
ation of Zn4O6+ cluster as SBU and BTB as linker produces
MOF-177, which has been the best performance material up to
last year, regarding the hydrogen storage capacity. Furthermore,
Caskey et al. reported three new phases of Zn/BTB adopting
polyreticular frameworks, which were obtained using polymer-
induced nucleation and different crystallization conditions.5b
4,4′,4′′-(Benzene-1,3,5-triyl-tris(benzene-4,1-diyl))tribenzoate
(BBC) ligand is a further elongated homologue of BTC with a
distance between the carboxylic groups of about 2 nm. The
presence of 7 aromatic rings in the molecule promotes the for-
mation of numerous weak π⋯π and C–H⋯π interactions in the
On the other hand, the coordination polymers are interesting
from the crystal engineering point of view, due to their crystalli-
nity and the tendency to produce supramolecular isomers. Even
aDepartment of Inorganic Chemistry, Dresden University of Technology,
Bergstr. 66, 01062 Dresden, Germany. E-mail: Stefan.Kaskel@chemie.
tu-dresden.de; Fax: +49 351 46337287
bDepartment of Physical Chemistry and Electrochemistry, Dresden
University of Technology, Bergstr. 66b, 01062 Dresden, Germany.
E-mail: Igor.Baburin@chemie.tu-dresden.de; Fax: +49 351 46335953;
Tel: +49 351 463 32637
cHelmholtz-Zentrum Berlin für Materialien und Energie BESSY-MX
Group, Albert-Einstein-Str. 15, 12489 Berlin, Germany.
E-mail: umue@helmholtz-berlin.de; Fax: +49 030 806214975;
Tel: +49 030 806214974
†Electronic supplementary information (ESI) available: Synthesis and
characterization of H3BBC, PXRD patterns and TG curves of DUT-40,
DUT-42, DUT-43, and DUT-44, details of dye adsorption experiments,
further crystallographic data, selected geometrical parameters for investi-
gated compounds. CCDC reference numbers 850713–850717. For ESI
and crystallographic data in CIF or other electronic format See DOI:
10.1039/c2dt12072k
4172 | Dalton Trans., 2012, 41, 4172–4179
This journal is © The Royal Society of Chemistry 2012

Scheme 1 Overview of the resulted MOFs.
resulted structures, which may cause interpenetration and
polycatenation.
Fig. 1 SBU unit of DUT-40 (a) and the crystal structure along the c
axis (b).
Zhou et al. used the BBC ligand in combination with zinc.9
The synthesis in the presence of two different bases has resulted
in the formation of two porous MOFs: Zn4(OH)2(H2O)2(py)2
(BBC)2 (py = pyridine) and Zn8(OH)4(BBC)4 with novel SBUs.
Recently, Furukawa et al. reported a new highly porous material
MOF-200 constructed from the BBC linker and Zn4O6+ cluster
as SBU.4 Shortly after, the same group reported on MOF-399 –
(Cu3(BBC)2) material based on Cu paddle-wheels, which is iso-
reticular to Cu3(BTC)2. The substitution of BTC by BBC leads
to the enlargement of the cubic unit cell edge from 26.34 Å in
Cu3(BTC)2 to 68.31 Å in MOF-399.7
In the present work, we report the synthesis and characteriz-
ation of five new 2D and 3D coordination polymers, based on
the BBC linker (Scheme 1). The synthesis conditions as well as
bitopic co-linkers (H2TDC, H2BPDC) or crystallization agents
have a crucial influence on the structure and topology of the
resulting compounds.
Fig. 2 SBU unit of DUT-41 with numbering scheme (a), and the
crystal structure along the c axis (b).
Results and discussion
Crystallographic results
(Fig. 1b), measured from atom to atom centre. After the lattice
solvent molecules were excluded from the structural model the
solvent-accessible voids were assessed by PLATON to be
67.8%.
Crystal structure of [Zn2(H2O)2(BBC)](NO3)(DEF)6 (1,
DUT-40‡). The H3BBC was synthesized (for more details see
ESI†) and used for the reaction with Zn(NO3)2·4H2O in DEF at
373 K. This led to the formation of 2D coordination polymer
DUT-40, which crystallizes in the monoclinic space group C2/c
(No. 15). The asymmetric unit contains one half of the formula
unit, which is generated by the crystallographic two-fold axis.
The SBU unit consists of two symmetrically equivalent Zn
atoms forming Zn2(COO)3 paddle-wheels with coordinated
water molecules in axial positions (Fig. 1a). It should be men-
tioned, that only few structures with Zn2(COO)3 SBU unit are
available in the Cambridge Structural Database.10 The distance
between Zn atoms is 3.32(7) Å. The Zn–O distances have
expected values in the range of 1.93(1)–2.16(4) Å. The
Zn2(COO)3 paddle-wheels are interconnected via BBC linker
molecules (Fig. 1a). All carboxylate groups of the linker adopt a
μ-carboxylato-κO:κO′ coordination mode leading to the for-
mation of layers parallel to (20-1) plane. The layers are intercon-
nected by several weak π⋯π interactions (see ESI†). As
expected from the trigonal geometry of both the SBU unit and
the linker, the crystal structure of 1 contains hexagonal channels
along the c direction with approximate dimensions of 18 × 26 Å
Crystal structure of Zn3(H2O)3(BBC)2 (2, DUT-41). Heating
Zn(NO3)2·4H2O, H3BBC, and 2,6-bipyridylnaphthalene at 80 °C
for 24 h in DMF as solvent led to the formation of a mixture of
different products. The crystals of one of them were studied by
single crystal X-ray diffraction. The compound named DUT-41
crystallizes in the monoclinic space group Cc (No. 9). The com-
pound contains a three-nuclear zinc cluster (Fig. 2a), where Zn
atoms exhibit different coordination geometry and are intercon-
nected by 5 carboxylate groups in μ-carboxylato-κO:κO′ coordi-
nation mode. The Zn1 has a nearly regular octahedral ZnO6
coordination geometry with neighbouring O–Zn–O angles range
80.93(12)–97.26(9)°. The Zn2 adopts strongly distorted tetra-
hedral geometry with a wide O–Zn–O angle range 94.27(11)–
126.54(11)° and is connected to Zn1 via three μ-carboxylic
groups.
The Zn1–Zn2 and Zn1–Zn3 distances within the cluster are
sufficiently longer in comparison to 1 (3.843(1) Å and 4.267(1)
Å, respectively) and the Zn2–Zn1–Zn3 angle is 152.0°.
This journal is © The Royal Society of Chemistry 2012
Dalton Trans., 2012, 41, 4172–4179 | 4173

Every Zn atom in the cluster is additionally coordinated by
one solvent molecule. Two BBC molecules, which lie in the par-
allel planes, connect the above-mentioned SBU units into a 2D
network. The crystal structure of 2 consists of the layers and
exhibits nearly regular hexagonal channels along [001] direction
with approximate diameter of 25 Å (Fig. 2b). The layers are held
together by numerous weak π⋯π interactions (see ESI†). After
the lattice solvent molecules were excluded from the structural
model the solvent-accessible voids were assessed by PLATON to
be 67.5%.
The paddle-wheel geometry in DUT-42 is mostly similar to
that in DUT-40 (Fig. 3), but the Zn–O bond lengths lie in the
narrower range 1.937(1)–1.977(1) Å. Numerous weak π⋯π
interactions between the frameworks stabilize the crystal struc-
ture (see ESI†). Despite of interpenetration, the structure has
hexagonal channels along the c direction. After exclusion of
lattice solvent molecules and cations from the structural model
the solvent-accessible voids were assessed by PLATON to be
60.9%.
Crystal structure of [Zn10(BBC)5(BPDC)2(H2O)10](NO3)
(DEF)28(H2O)8 (4, DUT-43). Maintaining the same synthetic
conditions as for compound 1 and using additional 4,4′-biphe-
nyldicarboxylic acid (H2BPDC), DUT-43 could be obtained.
The main differences between TDC and BPDC as bridging units
are the distances between carboxylate groups as well as the
angles between them. Thus, the distance between two carboxy-
late carbon atoms in TDC is 5.33 Å and the angle between them
is 147.5°. In the case of linear BPDC linker, the distance
between carboxylate groups is nearly twice as long as in TDC
(10.11 Å).
DUT-43 crystallizes in the monoclinic space group C2/c (No.
15). The crystal structure of DUT-43 is built up by two types of
2D units. The first one is a honeycomb layer containing Zn4/Zn5
trigonal paddle-wheel units (Fig. 4a) interconnected by BBC
linkers. The second unit consists of three honeycomb layers con-
nected together by BPDC molecules (Fig. 4d). The Zn1 atom of
Zn1/Zn3 containing paddle-wheel is bound by the BPDC linker
to the Zn2 atom from the neighbouring layer (Fig. 4c, 4d).
The resulted 3D architecture of DUT-43 (Fig. 4e) is formed
by the polycatenation of triple layers and interpenetration of
single and triple layers at the same time (Fig. 8).
Crystal
structure
of
[(C2H5)2NH2][Zn2(BBC)(TDC)]
(DEF)6(H2O)7 (3, DUT-42). Recently, the highly porous 3D
coordination polymer, namely UMCM-3, was obtained by Koh
et al.11 by combining angular 2,5-thiophenedicarboxylate (TDC)
linker, BTB and Zn4O cluster. Under similar reaction conditions
and using H3BBC instead of H3BTB, we obtained the yellow
hexagonally shaped crystals of DUT-42. Single crystal diffrac-
tion data revealed the hexagonal crystal system and chiral space
group P6522 (No. 179). The paddle-wheel SBU units are con-
nected by three μ-carboxylate groups of the BBC linker to form
a layer. The layers are interconnected into the 3D network by
TDC linkers, their carboxylic groups coordinate in a monoden-
tate fashion (Fig. 3a). This leads to non-equivalent C–O bond
lengths in the carboxylic group (see ESI†) as well as to the dis-
order of non-coordinated carboxylate oxygen atoms.
Assuming that the linker molecules are fully deprotonated, a
negatively charged framework is formed. Unfortunately, it was
impossible to locate the counterions from the difference Fourier
map, obviously due to the strong disorder. However, the elemen-
tal, as well as thermal gravimetric analyses of supercritically
dried sample give evidence of the presence of diethylammonium
cation, which can be formed under the synthetic conditions. TG
analysis indicates 6.83% weight loss in the range 25–250 °C
(boiling point of diethylamine 55.5 °C) (see ESI†). Additionally,
the nitrogen content of 1.22%, found from the elemental analy-
sis, corresponds to the framework composition [(C2H5)2NH2]
[Zn2(BBC)(TDC)]. A similar observation was made by Hou
et al. for the MCF-26 (MCF – metal–carboxylate framework)
compound,12 which is isoreticular to DUT-42.
Three pairs of zinc atoms (Zn1/Zn3, Zn2/Zn2#1 (#12−x, y,
2.5−z), and Zn4/Zn5) are interconnected into trigonal paddle-
wheels similar to that in compounds 1 and 3: two Zn atoms in
the SBU are interconnected by three μ-coordinated carboxylic
groups from the BBC linkers.
The coordination sphere of Zn4 is completed by one solvent
molecule (H2O) to form a distorted trigonal pyramid, and the
coordination sphere of Zn5 is completed by three solvent mol-
ecules giving rise to distorted octahedra (Fig. 4a). The coordi-
nation environment of Zn3 is completed by one water molecule
(Fig. 4c). After the lattice solvent molecules were excluded from
the structural model the solvent-accessible voids were assessed
by PLATON to be 62.9%.
Crystal
structure
of
[Co2(BBC)(NO3)(DEF)2(H2O)]
(DEF)6(H2O) (5, DUT-44). Heating Co(NO3)2·6H2O and
H3BBC at 120 °C for 12 h in DEF leads to the formation of crys-
talline product 5. The structure was solved in the monoclinic
space group C2/c (No. 15). The SBU unit of DUT-44 consists of
two cobalt atoms, which are coordinated each by six oxygen
atoms (Fig. 5a). The Co1–O bond lengths and O–Co1–O angles
lie within wide ranges of 1.988(2)–2.296(3) Å, and 57.87(13)–
105.06(10)°, respectively. This is caused by the coordination of
−
NO3 anion and one of the carboxylate groups in a bidentate
manner to Co1 (Fig. 5a). In contrast to Co1, Co2 has nearly
regular octahedral coordination environment having Co2–O
bond lengths and O–Co2–O angles in the range of 2.047(2)–
Fig. 3 SBU unit of DUT-42 (a), and view on the crystal structure
along c axis (b).
4174 | Dalton Trans., 2012, 41, 4172–4179
This journal is © The Royal Society of Chemistry 2012

Fig. 6 Underlying nets of layered coordination polymers DUT-40 and
DUT-44 (a); DUT-41 (b); and DUT-43 (c). Black circles represent the
centroids of Zn-clusters and open circles correspond to BBC.
molecules. The structure consists of 2D layers lying in the ab
plane (Fig. 5b). The layers are interconnected by weak C–H⋯O,
C–H⋯π and numerous π⋯π interactions (Table S7, ESI†). After
exclusion of lattice solvent molecules from the structural model,
the solvent-accessible voids were assessed by PLATON to be
54.9%.
Topological analysis
The topology of all coordination polymers presented in this
paper is either identical to or can be easily derived from that of a
honeycomb net (63). In the DUT-40 and DUT-44 structures the
trivalent nodes of the underlying net correspond (alternately) to
the paddle-wheel units and BBC linkers (black and white circles,
respectively, in Fig. 6a). Although the two structures belong to
the same C2/c space group, they are different with respect to the
stacking of the honeycomb layers: in the structure DUT-40 the
ˉ
stacking direction is [101] and there are six layers per translation
period while in DUT-44 the layers are packed in a more usual
fashion, namely, along [001] with four layers per translation
period.
Fig. 4 Crystal structure of DUT-43: (a) SBU of the single-layer; (b)
single-layer; (c) SBUs of triple-layer connected by BPDC; (d) triple-
layer; (e) view along c direction.
Double honeycomb (3,4)-connected layers (Fig. 6b) character-
ize the topology of the DUT-41 structure. Double layers are
formed since trinuclear Zn-clusters are interconnected by two
linkers lying in the parallel planes (Fig. 3a). The stacking direc-
tion is [001] with only two double layers per translation period.
The hexagonal structure of DUT-42 consists of three interpe-
netrated frameworks with the topology of the (3,5)-connected
gra net. Here, the BBC ligands again give rise to the trivalent
nodes of the underlying net. Binuclear Zn-units correspond to
the 5-connected nodes since they are bound to three BBC
ligands and additionally – by TDC – to the two symmetrically
equivalent Zn-units (Fig. 7). The crystal structure of DUT-42
consists of three-fold interpenetrated 3D networks related by 32
screw axis (rare interpenetration class IIa).13
The structure of the compound DUT-43 represents the
most complicated example (Fig. 4a) since it comprises four
honeycomb layers (identical to those in DUT-40) and further-
more four triple honeycomb (3,4,5)-connected layers (Fig. 6c)
per translation period along [001]. Nevertheless, the
sequences of symmetry operations generating the 4-layered
stacking (ABCD) along [001] are different for single and
Fig. 5 SBU unit of DUT-44 (a) and view on the crystal structure along
the c axis (b).
2.122(2) Å and 85.78(15)–94.46(11)°, respectively. The two Co
atoms are interconnected by two μ-carboxylate groups and one
oxygen atom from the third carboxylate group. In the case of
Co2, the coordination environment is completed by 3 DEF
This journal is © The Royal Society of Chemistry 2012
Dalton Trans., 2012, 41, 4172–4179 | 4175

Fig. 7 Three-fold interpenetrating nets (gra type) in the structure 3
(schematic view). TDC cross-linkers correspond to the dotted lines.
Fig. 9 The nitrogen adsorption (solid symbols) and desorption (open
symbols) isotherms at 77 K on DUT-40 (triangles), DUT-43 (squares),
and DUT-44 (circles).
2037 m2 g−1 for DUT-42, 1932 m2 g−1 for DUT-43,
1939 m2 g−1 for DUT-44.
This is remarkable, that the original structures of DUT-40,
DUT-42 and DUT-43 can be restored by soaking in DMF, or by
the adsorption of DMF from vapour. In the case of DUT-44 the
structural changes caused by activation are irreversible, and the
resolvation does not lead to the recovery of the as-made structure
(Fig. S5, ESI†).
Fig. 8 Schematic view of polycatenation and interpenetration in the
structure of DUT-43: catenated triple honeycomb layers (red and blue)
and a single honeycomb layer (black) penetrating them.
For some applications (for example, heterogeneous catalysis
in the liquid phase), the availability of the solvent free compound
is non-essential. More important in this case is that the accessi-
bility of the pore system for the substrate molecules is
guaranteed.
triple
layers
and
, respectively. The triple layers are
formed owing to the BPDC ligands which connect binuclear Zn-
units (within a given layer) to the two additional ones in the
neighbouring (up and down) layers. Finally, triple layers are cate-
nated with each other and also penetrated by a set of single hon-
eycomb layers (Fig. 8). Thus, in this structure we have a rare
example of simultaneous occurrence of both polycatenation14
(between triple layers) and interpenetration (between triple and
single honeycomb layers, respectively).
The dye molecules are a good model system, because the
adsorption can be monitored optically, by the colour change of
the crystals. Additionally, some information about the substrate
size limitation can be collected, since a vast series of dyes with
different sizes and polarity is available. The adsorption of Isatin,
Brilliant green, Nile red, Nile blue, Methylene blue, Fluorescein,
Disperse red 1, Disperse red 13, Food red No. 2, and Brilliant
yellow (Table S1, ESI†) carried out in DMF or DEF as solvent
confirm the accessibility of the pores for most of the investigated
dyes. It was found, that in the case of DUT-40 all tested dyes
can penetrate the framework. The DUT-42 can adsorb Brilliant
green, Nile blue, Nile red, Methylene blue, Disperse red 1, Dis-
perse red 13 and Brilliant yellow. Furthermore, DUT-43 is able
to adsorb Fluorescein and Isatin in addition to the dyes which
could be adsorbed on DUT-42. It should be mentioned, that the
estimation of the adsorption ability of Co based DUT-44 was
difficult, because of its own intensive purple colour of the crys-
tals. In this case, the adsorption of Brilliant green, Nile red, Nile
blue, and Methylene blue (Fig. 10) could be postulated
definitely.
Physisorption experiments
To estimate the porosity of investigated compounds the nitrogen
adsorption experiments were performed at 77 K. Thermogravi-
metric analyses of the compounds showed that up to 47.3% (for
1), 49.2% (for 2), 40.1% (for 3), and 49.7% (for 4) of the total
mass is lost in the temperature range 298–573 K, but no pro-
nounced steps are present (Fig. S1, S3–S5, ESI†). The conven-
tional thermal activation in vacuum at 423 K leads to the
materials which show no significant nitrogen adsorption. After
activation with supercritical CO2, the samples lose the pristine
structure (Fig. S1, S2, S4, S5, ESI†), but they are able to adsorb
nitrogen at 77 K and the specific surface area could be estimated
from the isotherms (Fig. 9). The multipoint BET surface areas
are 34 m2 g−1 for DUT-40, 397 m2 g−1 for DUT-43, and
479 m2 g−1 for DUT-44. The DUT-42 shows no nitrogen uptake.
Measured surface areas are much lower than expected from
the calculation. The geometrically calculated surface area15 is
2606 m2 g−1 for DUT-40, 2505 m2 g−1 for DUT-41,
Conclusions
Five new coordination polymers, namely DUT-40 – DUT-44,
based on the trigonal linker BBC were obtained under different
synthesis conditions. DUT-40, DUT-41 and DUT-44 possess
2D-layered crystal structures topologically related to that of the
4176 | Dalton Trans., 2012, 41, 4172–4179
This journal is © The Royal Society of Chemistry 2012

Synthesis of [Zn3(H2O)3(C45H27O6)2] (2, DUT-41)
Zn(NO3)2·4H2O (26.15 mg, 0.100 mmol), H3BBC (20 mg,
0.030 mmol) and 2,6-bipyridylnaphthalene (10 mg,
0.035 mmol) were dissolved in 2 mL DMF. The solution was
sonicated for 2 min and heated in a Pyrex tube for 24 h at
353 K. Small single crystals of 2 and other amorphous by-
products were obtained.
Yield could not be determined and elemental analysis could
not be performed due to the product impurity.
Synthesis of [(C2H5)2NH2][Zn2(C45H27O6)(C6H2O4S)]
(DEF)6(H2O)7 (3, DUT-42)
Fig. 10 Adsorption of methylene blue on (a) DUT-40, (b) DUT-42, (c)
DUT-43 and (d) DUT-44.
Zn(NO3)2·4H2O (156.0 mg, 0.6 mmol), H3BBC (45.0 mg,
0.067 mmol) and H2TDC (51.6 mg, 0.3 mmol) were dissolved
in 2 mL DEF and heated in a Pyrex tube for 96 h at 353 K. The
resulting yellow hexagonal sticks were separated by decanting
the mother liquor. The crystals were washed with fresh DMF
three times and dried in argon flow at room temperature (yield:
89 mg, 77.6% based on H3BBC).
Elemental analysis of as-synthesized material: calc.: % C
57.66, % H 6.84, % N 5.54% S 1.81; found: % C 57.42, % H
6.64, % N 5.41, % S 1.42. Elemental analysis of supercritically
dried material: calc.: % C 63.65, % H 3.95, % N 1.35% S 3.09;
found: % C 61.72, % H 4.21, % N 1.22, % S 3.08. IR of
“as-synthesized” phase: ν/cm−1 = 2984 (w), 2947 (w), 2897 (w),
1632 (s), 1607 (s), 1526 (m), 1402 (vs), 1387 (s), 1263 (m),
1215 (m), 1204 (w), 1111 (m), 1005 (m), 947 (w), 824 (m), 783
(s), 733 (w), 735 (w), 648 (m), 555 (w), 517 (m). IR of CO2
supercritically dried phase: 2976 (w), 2939 (w), 1683 (m), 1604
(s), 1523 (m), 1386 (s), 1177 (m), 1003 (m), 825 (m), 783 (s),
733 (w), 650 (m), 505 (m).
honeycomb net (63). Using the H2TDC as additional bifunc-
tional co-linker led to the formation of DUT-42 with triply inter-
penetrated 3D architecture. DUT-43, obtained by co-
polymerization of H3BBC, H2BPDC and Zn2+, shows an excep-
tional 3D structure, formed by polycatenation of triple layers and
interpenetration between triple and single layers at the same
time.
During solvent removal, the transformation of the structures
takes place and the resulting porous solids have specific surface
areas up to 480 m2 g−1. The original crystal structures of
DUT-40, DUT-42 and DUT-43 can be restored by exposing the
activated materials to DMF. All investigated compounds have
pores accessible for large dye molecules, which was confirmed
by liquid phase adsorption experiments.
Experimental
Synthesis of [Zn10(C45H27O6)5(C14H8O4)2(H2O)10](NO3)
(DEF)28(H2O)8 (4, DUT–43)
General remarks
Zinc nitrate tetrahydrate (≥98.5%, Merck), cobalt nitrate hexahy-
drate (99%, Chempur), H2TDC (≥98%, TCI) and H2BPDC
(97%, Aldrich) were used as received. N,N′-Diethylformamide
(DEF) was dried over phosphorous pentoxide and stored under
argon atmosphere. The H3BBC was synthesized according to
published procedure (see ESI† for more details).16
Zn(NO3)2·4H2O (283.0 mg, 1.08 mmol), H3BBC (162.1 mg,
0.23 mmol), and H2BPDC (65.5 mg, 0.27 mmol) were sus-
pended in 10 mL DEF and heated in a Pyrex tube 72 h at 373 K
to give colourless crystals. They were filtered under argon atmos-
phere, washed with DMF and dried in an argon flow at room
temperature (yield: 181.3 mg, 51.5% based on H3BBC).
Elemental analysis: calc.: % C 61.53, % H 6.50, % N 5.30;
found: % C 61.03, % H 5.94, % N 5.77. IR: ν/cm−1 = 3067 (w),
3035 (w), 2933 (w), 2860 (w), 1668 (s), 1605 (s), 1568 (m),
1548 (m), 1527 (w), 1494 (m), 1384 (vs), 1253 (m), 1178 (w),
1088 (s), 1063 (w), 1005 (m), 828 (m), 784 (s), 771 (m), 734
(m), 707 (m), 688 (m).
Synthesis of [Zn2(H2O)2(C45H27O6)](NO3)(DEF)6 (1, DUT-40)
H3BBC (48.6 mg, 0.07 mmol) and Zn(NO3)2·4H2O (85.0 mg,
0.33 mmol) were dissolved in 10.5 mL DEF and two drops of
acetic acid were added. The solution was heated in a Pyrex tube
for 48 h at 373 K. The resulting light yellow crystals were col-
lected by filtration under argon atmosphere, washed with DMF
and dried under reduced pressure at room temperature (yield:
84.8 mg, 87% based on H3BBC).
Synthesis of [Co2(C45H27O6)(NO3)(DEF)2(H2O)](DEF)6(H2O)
(5, DUT-44)
Elemental analysis: calc.: % C 60.08, % H 6.52, % N 6.54;
found: % C 60.43, % H 6.90, % N 6.08. IR: ν/cm−1 = 3040 (w),
2938 (w), 2864 (w), 1651 (s), 1602 (s), 1564 (m), 1548 (w),
1528 (w), 1495 (m), 1383 (vs), 1252 (m), 1180 (w), 1090 (s),
1060 (w), 1005 (m), 829 (m), 785 (s), 735 (w), 706 (w),
688 (w).
Co(NO3)2·6H2O (157.5 mg, 0.54 mmol) and H3BBC (81.0 mg,
0.12 mmol) were dissolved in 10.5 mL DEF and heated in a
Pyrex tube for 12 h at 120 °C. The resulting purple crystals were
collected by filtration under argon atmosphere, washed with
fresh DEF and dried in an argon flow at room temperature
(yield: 99.0 mg, 48.9% based on H3BBC).
This journal is © The Royal Society of Chemistry 2012
Dalton Trans., 2012, 41, 4172–4179 | 4177

Elemental analysis: calc.: % C 60.45, % H 7.10, % N 7.46;
found: % C 60.45, % H 7.09, % N 7.44. IR: ν/cm−1 = 3046 (w),
2935 (w), 2861 (w), 1663 (s), 1602 (s), 1568 (m), 1551 (m),
1527 (w), 1496 (m), 1384 (s), 1303 (w), 1255 (m), 1179 (w),
1090 (s), 1060 (w), 1004 (m), 830 (m), 785, 732 (m), 708 (m),
681 (m), 659 (m).
DUT-43: C273H195N4O52Zn10; monoclinic, C2/c, Fw =
5017.03, a = 23.934(5); b = 41.860(8); c = 45.532(9) Å, β =
90.12(3)°, V = 45 617(16), T = 296(2) K, Z = 4, Dc = 0.731 g
cm−3, μ = 0.558 mm−1, F (000) = 10 308, θmax = 36.97°, reflec-
tions collected 132 373, unique 32 809 [Rint = 0.0584), final R
indices [I > 2σ(I)] were R1 = 0.0911, wR2 = 0.2671, R indices
(all data) R1 = 0.1066, wR2 = 0.2840, GOF = 1.129.
DUT-44: C55H49Co2N3O12; monoclinic, C2/c, Fw = 1061.83,
a = 39.776(8); b = 24.693(5); c = 21.823(4) Å, β = 117.94(3)°,
V = 18 936(6), T = 296(2) K, Z = 8, Dc = 0.745 g cm−3, μ =
0.386 mm−1, F (000) = 4400, θmax = 30.60°, reflections col-
lected 57 847, unique 13 628 [Rint = 0.0344), final R indices
[I > 2σ(I)] were R1 = 0.0702, wR2 = 0.2145, R indices (all data)
R1 = 0.0787, wR2 = 0.2242, GOF = 1.086.
Single crystal X-ray analysis
The single crystals of investigated compounds DUT-40–44 were
placed inside the 0.3 mm capillary with small amount of the
mother liquor. The datasets were collected at Helmholtz-
Zentrum Berlin for Materials and Energy on beamline
BESSY-MX BL14.2, equipped with MAR225 CCD area detec-
tor and 1-circle goniometer. The monochromated radiation with
λ = 0.88561 Å was used for all experiments. The images were
collected using ϕ-scan technique with scan step Δϕ = 1°. The
indexing, integration and scaling were performed using XDS
program.17 Due to low absorption coefficients, absorption cor-
rections were not performed. The structures were solved by
direct methods and refined in anisotropic approximation for all
non-hydrogen atoms by full matrix least-square on F2 using
SHELX.18 Hydrogen atoms are placed in calculated positions
according to the geometry of parent atoms and refined using
“riding model” with Uiso(H) = 1.5Uiso(C) for CH3 groups and
Uiso(H) = 1.2Uiso(C) for all other atoms. Due to the high
amount of disordered solvent molecules in all investigated struc-
tures, the SQUEEZE routine of PLATON was applied to all data-
sets to modify reflections intensities and to exclude the electron
density of disordered solvent molecules.19 The full data for crys-
tallographic experiments are given in Table S2, ESI.†. CCDC
reference numbers 850713–850717 contain the full information
for crystal structures DUT-40–44.† The topology of the networks
was analysed using program package TOPOS.20
Physisorption experiments
Nitrogen physisorption isotherms were measured at 77 K up to
1 bar using a Quadrasorb apparatus (Quantachrome Co.). Prior to
all adsorption measurements, the samples were activated using
supercritical CO2.
The BET surface area was also geometrically calculated
according to a published procedure.15
Liquid phase adsorption experiments: 1 mmol L−1 solutions
of Isatin, Brilliant green, Nile red, Nile blue, Methylene blue,
Fluorescein, Disperse red 1, Disperse red 13, Food red No. 2 and
Brilliant yellow in DMF (DUT-40 and 42) or DEF (DUT-43 and
44), were prepared. The crystals of investigated compounds were
placed into corresponding dye-containing solution. After three
days, the Dye@MOF crystals were investigated under the
microscope.
For resolvation experiments from the liquid phase, the crystals
of activated compounds were soaked in DMF or DEF for three
days. For resolvation experiments from the vapour, the samples
were stored in a saturated vapour atmosphere of DMF for 7 days.
Crystal data for:
Acknowledgements
DUT-40: C45H27O8Zn2; monoclinic, C2/c, Fw = 826.41, a =
19.834(4); b = 42.111(8); c = 12.913(3) Å, β = 118.69(3)°, V =
9461(3), T = 296(2) K, Z = 4, Dc = 0.580 g cm−3, μ =
0.952 mm−1, F (000) = 1684, θmax = 30.48°, reflections col-
lected 47 983, unique 10 707 [Rint = 0.0838), final R indices [I >
2σ(I)] were R1 = 0.0703, wR2 = 0.1866, R indices (all data)
R1 = 0.1311, wR2 = 0.2089, GOF = 0.845.
DUT-41: C90H54O15Zn3; monoclinic, Cc, Fw = 1571.44, a =
24.127(5); b = 41.811(8); c = 20.186(4) Å, β = 115.27(3)°, V =
18 414(6), T = 296(2) K, Z = 4, Dc = 0.567 g cm−3, μ =
0.747 mm−1, F (000) = 3216, θmax = 36.87°, reflections col-
lected 96 110, unique 40 518 [Rint = 0.0544), final R indices [I >
2σ(I)] were R1 = 0.0567, wR2 = 0.1484, R indices (all data)
R1 = 0.0710, wR2 = 0.1576, GOF = 0.912.
This work was financially supported by the German Research
Foundation (SPP 1362), the BMWT (FKZ: 0327796B), and the
Helmholtz-Zentrum Berlin für Materialien und Energie.
Notes and references
‡The compositions of DUT-40, DUT-42, DUT-43, and DUT-44 were
derived from TG and elemental analysis data. The composition of
DUT-41 is based on the single crystallographic X-ray analysis and does
not include the solvent guest molecules.
1 (a) O. M. Yaghi, M. O’Keeffe, N. W. Ockwig, H. K. Chae, M. Eddaoudi
and J. Kim, Nature, 2003, 423, 705; (b) M. Eddaoudi, J. Kim, N. Rosi,
D. Vodak, J. Wachter, M. O’Keeffe and O. M. Yaghi, Science, 2002, 295,
469; (c) S. T. Meek, J. A. Greathouse and M. D. Allendorf, Adv. Mater.,
2011, 23, 249.
2 (a) C.-D. Wu, A. Hu, L. Zhang and W. Lin, J. Am. Chem. Soc., 2005,
127, 8940; (b) Y. Liu, W. Xuan and Y. Cui, Adv. Mater., 2010, 22, 4112;
(c) D. Farrusseng, S. Aguado and C. Pinel, Angew. Chem., Int. Ed., 2009,
48, 7502; (d) A. Corma, H. Garcia and F. X. Llabres i Xamena, Chem.
Rev., 2010, 110, 4606.
DUT-42: C51H29O10SZn2; hexagonal, P6522, Fw = 964.54, a
= 24.057(3); c = 26.996(5) Å, V = 13 530(3), T = 296(2) K, Z =
6, Dc = 0.710 g cm−3, μ = 1.053 mm−1, F (000) = 2946, θmax
36.97°, reflections collected 155 346, unique 11 149 [Rint
=
=
0.0934), final R indices [I > 2σ(I)] were R1 = 0.0428, wR2 =
0.1086, R indices (all data) R1 = 0.0524, wR2 = 0.1150, GOF =
1.061.
3 M. Padmanaban, P. Müller, K. Gedrich, R. Grünker, V. Bon,
I. Senkovska, C. Lieder, S. Baumgärtner, S. Opelt, F. Glorius, S. Kaskel,
E. Klemm, E. Brunner and S. Kaskel, Chem. Commun., 2011, 47, 12089.
4178 | Dalton Trans., 2012, 41, 4172–4179
This journal is © The Royal Society of Chemistry 2012

4 H. Furukawa, N. Ko, Y. B. Go, N. Aratani, S. B. Choi, E. Choi, A.
Ö. Yazaydin, R. Q. Snurr, M. O’Keeffe, J. Kim and O. M. Yaghi,
Science, 2010, 329, 424.
10 F. Allen, Acta Crystallogr., Sect. B: Struct. Sci., 2002, 58, 380.
11 K. Koh, A. G. Wong-Foy and A. J. Matzger, J. Am. Chem. Soc., 2010,
132, 15005.
5 (a) J. P. Zhang, X. C. Huang and X. M. Chen, Chem. Soc. Rev., 2009, 38,
2385; (b) S. R. Caskey, A. G. Wong-Foy and A. J. Matzger, Inorg.
Chem., 2008, 47, 7751; (c) R. Grünker, I. Senkovska, R. Biedermann,
N. Klein, A. Klausch, I. A. Baburin, U. Mueller and S. Kaskel,
Eur. J. Inorg. Chem., 2010, 3835; (d) T. A. Makal, A. A. Yakovenko and
H.-C. Zhou, J. Phys. Chem. Lett., 2011, 2, 1682.
6 N. Klein, I. Senkovska, I. A. Baburin, R. Grünker, U. Stoeck,
M. Schlichtenmayer, B. Streppel, U. Mueller, S. Leoni, M. Hirscher and
S. Kaskel, Chem.–Eur. J., 2011, 17, 13007.
7 H. Furukawa, Y. B. Go, N. Ko, Y. K. Park, F. J. Uribe-Romo, J. Kim,
M. O’Keeffe and O. M. Yaghi, Inorg. Chem., 2011, 50, 9147.
8 B. L. Chen, M. Eddaoudi, S. T. Hyde, M. O’Keeffe and O. M. Yaghi,
Science, 2001, 291, 1021.
9 D. Sun, Y. Ke, T. M. Mattox, S. Parkin and H.-C. Zhou, Inorg. Chem.,
2006, 45, 7566.
12 L. Hou, J.-P. Zhang and X.-M. Chen, Cryst. Growth Des., 2009, 9, 2415.
13 V. A. Blatov, L. Carlucci, G. Ciani and D. M. Proserpio, CrystEngComm,
2004, 6, 378.
14 L. Carlucci, G. Ciani and D. M. Proserpio, Coord. Chem. Rev., 2003,
246, 247.
15 T. Dueren, F. Millange, G. Ferey, K. S. Walton and R. Q. Snurr, J. Phys.
Chem. C, 2007, 111, 15350.
16 (a) J. Lu, Y. Tao, M. D’iorio, Y. Li, J. Ding and M. Day, Macromolecules,
2004, 37, 2442; (b) J. F. Dienstmaier, K. Mahata, H. Walch,
W. M. Heckl, M. Schmittel and M. Lackinger, Langmuir, 2010, 26,
10708.
17 W. Kabsch, J. Appl. Crystallogr.,, 1993, 26, 795.
18 G. M. Sheldrick, Acta Crystallogr., 2008, A64, 112.
19 A. L. Spek, Acta Crystallogr., 2009, D65, 148.
20 V. A. Blatov, IUCr CompComm. Newslett., 2006, 7, 4.
This journal is © The Royal Society of Chemistry 2012
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