CFA-4-a fluorinated metal-organic framework with exchangeable interchannel cations

Article abstract of DOI:10.1039/c7dt00582b

The syntheses and crystal structures of the fluorinated linker 1,4-bis(3,5-bis(trifluoromethyl)-1H-pyrazole-4-yl)benzene (H₂-tfpb; 1) and the novel metal-organic framework family M[CFA-4] (Coordination Framework Augsburg University-4), M[Cu₅(tfpb)₃] (M = Cu(i), K, Cs, Ca(0.5)), are described. The ligand 1 is fully characterized by single crystal X-ray diffraction, photoluminescence-, NMR-, IR spectroscopy, and mass spectrometry. The copper(i)-containing MOF crystallizes in the hexagonal crystal system within the chiral space group P6₃22 (no. 182) and the unit cell parameters are as follows: a = 23.630(5) ?, c = 41.390(5) ?, V = 20 015(6) ?³. M[CFA-4] features a porous 3-D structure constructed from pentanuclear copper(i) secondary building units {CuI5(pz)₆}^- (pz = pyrazolate). Cu(I)[CFA-4] is fully characterized by synchrotron single crystal X-ray diffraction, thermogravimetric analysis, variable temperature powder X-ray diffraction, IR spectroscopy, photoluminescence and gas sorption measurements. Moreover, thermal stability and gas sorption properties of K[CFA-4] and Cu(I)[CFA-4] are compared.

Full text of DOI:10.1039/c7dt00582b

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Joseph T. Hupp, Omar K. Farha et al.
Efficient extraction of sulfate from water using
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CFA-4 - a fluorinated metal-organic framework with
exchangeable interchannel cations
a
a
a
b
b
b
*a
J. Fritzsche, M. Grzywa, D. Denysenko, V. Bon, I. Senkovska, S. Kaskel and D. Volkmer
The syntheses and crystal structures of the fluorinated linker 1,4-bis(3,5-bis(trifluoromethyl)-1H-pyrazole-4-
yl)benzene (H -tfpb; 1) and the novel metal-organic framework family M[CFA-4] (Coordination Framework
Augsburg University-4), M[Cu (tfpb) ] (M = Cu(I), K, Cs, Ca(0.5)), are described. The ligand 1 is fully
Received 00th January 20xx,
Accepted 00th January 20xx
DOI: 10.1039/x0xx00000x
2
5
3
www.rsc.org/
characterized by single crystal X-ray diffraction, photoluminescence-, NMR-, IR spectroscopy, and mass
spectrometry. The copper(I)-containing MOF crystallizes in the hexagonal crystal system within the chiral space
group P6
3
22 (no. 182) and the unit cell parameters are as follows: a = 23.630(5) Å, c = 41.390(5) Å, V =
3
2
0015(6) Å . M[CFA-4] features a porous 3-D structure constructed from pentanuclear copper(I) secondary
building units {Cu I }- (pz = pyrazolate). Cu(I)[CFA-4] is fully characterized by synchrotron single crystal
(pz)
5 6
X-ray diffraction, thermogravimetric analysis, variable temperature powder X-ray diffraction, IR spectroscopy,
photoluminescence and gas sorption measurements. Moreover, thermal stability and gas sorption properties of
K[CFA-4] and Cu(I)[CFA-4] are compared.
storage and environment improvement.10 Another example that
demonstrates the influence of the number of fluorous moieties
Introduction
Porous and crystalline coordination polymers, i.e. metal-organic has recently been published as UiO-66-type FMOFs.11 In UiO-
frameworks (MOFs), have attracted the interest of the scientific 66-F and UiO-66-CF a positive effect of fluorine substitution on
3
community during the past 20 years. Whereas at the beginning the oxygen adsorption capacity was observed. The authors
the focus was laid upon applications in gas storage,1 these suppose that fluorine atoms have a positive interaction with
materials later on were tested for a wide range of different oxygen, but not with nitrogen.
2
3
4
applications, such as drug delivery, sensing, gas separation
and catalysis.
Besides the capture and storage of (chloro-)fluorocarbons, MOFs
5
12
find application in photochemistry, as electroluminescent
Replacing hydrogen atoms by fluorine atoms in a MOF-structure displays and chemical sensors, biosensors14 and fluorescent
13
leads to so-called FMOFs (fluorous metal-organic frameworks), sensors.15 The basic principle of fluorescence-based sensing is,
as published in 2007 for the first time.6
that these materials show a “turn-on” or “turn-off” behaviour,
Compared to structurally analogous compounds lacking fluorine when a special analyte is introduced in the system. This works
substituents, FMOFs with fluoro-lined or fluoro-coated channels for gases,16 ions, pesticides as well as for explosives. The
or cavities are expected to possess an enhanced thermal and latter materials are often highly electron-deficient nitrated
chemical stability, hydrophobicity and stability against (self-) organic compounds that act as good electron acceptors leading
17
18
7
oxidation and photolytic decomposition. Furthermore, FMOFs to a fluorescence quenching of a MOF, and thus allowing their
show unique properties such as superacidity, low surface energy specific detection.
and surface tension and excellent optical properties such as For applications of MOFs in gas separation or sensing it is
8
persistent luminescence. Owing to the strong hydrophobicity, important that the sample is stable and has a high volumetric
carboxylate-based FMOFs become water-resistant. In 2015, density of uniform active sites. Small molecules as for example
MOFF-5, a superhydrophobic material with high porosity and an carbon monoxide can bind reversibly at low temperatures and
2
-1
accessible surface area of 2445 m g , that shows a high capacity can be easily removed again.
for the storage of fluorinated greenhouse gases (up to 225 wt% We showed this in previous works on CFA-819 and CFA-9,20
for perfluorohexane), was announced.9
The number as well as the position of introduced fluorine atoms monoxide. We further published Cu -MFU-4
that contain Cu(I) sites which are able to reversibly bind carbon
I
21
l
,
a
have huge influence on the behaviour of the structure. The representative of the MFU-4 family, that is highly robust against
FMOFs TKL-104-TKL-107, for instance, show an increased thermal and hydrolytic decomposition and contains highly
stability as well as high surface areas and excellent ability for H
2
reactive, threefold-coordinated unsaturated open Cu(I)-metal
I
storage and CO capture, what makes them applicable in energy centres. Cu -MFU-4
2
l
shows fully reversible chemisorption of
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2 2 2
small molecules such as O , N or H with high isosteric heats of
adsorption as well as strong binding of carbon monoxide. This
leads to the supposition, that introduction of unsaturated Cu(I)
sites into a MOF could be a promising approach towards
materials suitable for gas separation or sensing applications as
well as for catalytic applications.
We here report on the synthesis and structure of a new copper(I)-
based MOF family M[CFA-4], which is synthesized from the
fluorinated organic ligand 1,4-bis(3,5-bis(trifluoromethyl)-1H
-
pyrazole-4-yl)benzene (H -tfpb; ). The H -tfpb ligand was
2
1
2
successfully synthesized via a twofold Suzuki-coupling reaction.
Its crystal structure was determined by single crystal X-ray
structure analysis. In addition to the synchrotron single crystal
X-ray diffraction, Cu(I)[CFA-4] was characterized by
thermogravimetric analyses, variable temperature X-ray
diffraction, IR spectroscopy, photoluminescence and gas
sorption measurements. Moreover, thermal stability and porosity
of K[CFA-4] and Cu(I)[CFA-4] are compared to each other.
Results and discussion
Syntheses and characterization
Scheme 1 Syntheses of 1,4-bis(3,5-bis(trifluoromethyl)-1H-pyrazole-4-yl)benzene
1, Cu(I)[CFA-4] and M[CFA-4] (DME = 1,2-dimethoxyethane).
1
2
,4-bis(3,5-bis(trifluoromethyl)-1H-pyrazole-4-yl)benzene (H -
tfpb; 1) was synthesized in a twofold Suzuki-coupling reaction
of commercially available 1,4-bis(4,4,5,5-tetramethyl-1,3,2-
dioxaborolan-2-yl)benzene
bis(trifluoromethyl)-1H-pyrazole22 (Scheme 1).
Cu(I)[CFA-4] framework was obtained as hexagonal prisms
Fig. 1a-b) after heating a DMF solution of and copper(II)
nitrate trihydrate at 120 °C (Scheme 1). In a different synthetic
approach, a solution of and copper(II) nitrate trihydrate were
with
4-iodo-3,5-
(
1
1
heated in MeOH in the presence of 2,6-lutidine, where hexagonal
prismatic-bipyramidal crystals of Cu(I)[CFA-4] were obtained
(
Fig. 1c-d).
Substituted M[CFA-4] frameworks (Mn+ = K , Cs , Ca ) were
obtained via postsynthetic cation exchange reactions upon
treatment of Cu(I)[CFA-4] with a solution of the corresponding
+
+
2+
2
metal nitrate in a DMF/H O mixture at room temperature.
Detailed reaction information is shown in the experimental part.
The Cu/M molar ratios in the obtained products were determined
by energy dispersive X-ray spectroscopy (EDX) and correspond
well to the expected theoretical values (5:1 for singly charged
Figure 1 Cu(I)[CFA-4]: (a) optical micrograph after synthesis in DMF as solvent;
b) SEM image after synthesis in DMF as solvent; (c) optical micrograph after
+
+
2+
cations K and Cs and 10:1 for a doubly charged cation Ca ,
(
see ESI Figs. S18-S20; Table S3). XRPD patterns of metal synthesis with solvent methanol and 2,6-lutidine; (d) SEM image after synthesis
with solvent methanol and 2,6-lutidine.
exchanged M[CFA-4] frameworks show similar peak positions
as Cu(I)[CFA-4] (see ESI Figs. S12-13).
2
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Crystal structure analyses
1
∙
1
,4-bis(3,5-bis(trifluoromethyl)-1H-pyrazole-4-yl)benzene
2MeOH (H -tfpb ∙2MeOH; ∙2CH OH).
∙2MeOH crystallizes in the monoclinic crystal system within
2
C
16
H
6
F
12
N
4
3
the space group
C2/m (no. 12). Detailed description of the crystal
structure of H
S2, Table S1).
2
-tfpb∙2MeOH is presented in the ESI (Figs. S1,
5 3
Cu(I)[Cu (tfpb) ] ∙4.75 DMF (Cu(I)[CFA-4]).
A synchrotron single crystal X-ray diffraction study reveals that
Figure 2 ORTEP-style plot of the asymmetric unit of Cu(I)[CFA-4]. Thermal
ellipsoids probability: 50 %. Disordered F-atoms were omitted for clarity.
Cu(I)[CFA-4] crystallizes in the hexagonal crystal system in the
chiral space group
3
P6 22 (no. 182).
The asymmetric unit consists of five copper atoms and one and
2-
a half of the tfpb molecules (Fig. 2).
Figure 3 (a) Excerpt of the coordination framework of M[CFA-4] featuring pentanuclear Cu(I) unit. (b) Representation of a single SBU of M[CFA-4]. CF
3
-groups were
omitted for clarity. (c) Schematic packing diagram representing interconnected SBUs of M[CFA-4], view in the -direction. (d) Crystal structure of M[CFA-4] with
c
channels (represented by yellow spheres), view in the
c
-direction. Disordered CF
3
-groups (a-c), solvent molecules and hydrogen atoms (a-c) were omitted for clarity.
Cu(I)[CFA-4] features a 3-D porous framework structure
constructed from pentanuclear {Cu
units (SBUs). Within the {Cu
I(pz)
5 6
I(pz) }- secondary building
}- SBU, five Cu(I) ions are
5
6
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connected by twelve nitrogen atoms belonging to the pyrazolate range of 200-300 °C, the weight loss (7.4 %) is attributed to the
moieties of tfpb2- ligands. The pentanuclear copper(I) unit, removal of DMF molecules coordinated to the Cu ions in the
+
5
Cu N
12 are composed of two distorted trigonal-planar channels and corresponds to two DMF molecules per one Cu+
coordinated copper centres, Cu3 and Cu5, and three linearly ion (calculated weight loss 7.4 %). The next step between
twofold-coordinated copper (I) ions, Cu4 (Cu2) and Cu1. For the 450-800 °C is connected with gradual decomposition of the
twofold-coordinated atoms, the N-Cu-N angles range from framework. Compared to Cu(I)[CFA-4], the TGA curve of
1
77.84(11) to 179.87(13) °, whereas the Cu-N distances are in K[CFA-4] (black line) shows no weight loss until about 300 °C
+
the range of 1.860(2) to 1.891(2) Å. The Cu-N distances for indicating that no solvent molecules are coordinated to K ions.
trigonal-planar coordinated copper ions range from 1.948(2) to Such behavior can be explained by very weak coordinating
+
1
.979(2) Å. These values are similar to those observed for the properties of K ions. Above 300 °C, the framework starts to
3 5 2 5 4 6
NH] {Cu [3-(C F )IndF ]
}- ([3- decompose.
+
coordination compound [Et
)IndF ]H 3-pentafluoroethyl-4,5,6,7-tetrafluoro-1H-
(
C
2
F
5
4
=
indazolate) featuring similar pentanuclear Cu(I) coordination
units.23 To the best of our knowledge, M[CFA-4] represents the
first example of a copper-containing MOF family in which the
pentanuclear copper(I) SBU was found and structurally
characterized. The {Cu
framework are interconnected by benzene rings of tfpb ligand,
thus creating one-dimensional channels expanding in -direction
5 6
I(pz) }- SBUs of the M[CFA-4]
2-
c
of the crystal lattice (see Fig. 3d). Taking the van der Waals radii
of fluorine atoms (1.35 Å) into account, the narrowest channel
diameter calculated between the fluorine atoms of the CF -
3
groups is 14.3 Å. The estimation with the program SQUEEZE24
reveals that the initial solvent accessible void volume is
3 -1
1
1724.2 Å3 (0.64 cm g ), which is 58.6 % of the unit cell
volume probe radius of 1.68 Å,
(
20015(6) Å3) for
a
corresponding to the approximate van der Waals radius of
argon.25 In the crystal structure of Cu(I)[CFA-4] the channels
are occupied by disordered DMF molecules and Cu -ions, which
+
Figure 4: Temperature dependent weight loss of Cu(I)[CFA-4] (red line) and
K[CFA-4] (black line) under flowing nitrogen gas.
compensate a negative charge of the lattice. As the UV-Vis
spectrum of Cu(I)[CFA-4] (see ESI Fig. S31) shows no typical
+
band for Cu(II), we suppose that there are only Cu -ions in the
channels. These Cu -ions can be readily exchanged by other ions
Phase purity of Cu(I)[CFA-4] and K[CFA-4] was confirmed by
XRPD measurements (Fig. 5 and 6, respectively) of samples
stored under ambient conditions. The experimental XRPD
pattern is consistent with one calculated from the single crystal
structural data (see Fig. 5). Differences in peak intensities are due
to occluded solvent molecules. Variable temperature X-ray
powder diffraction studies of Cu(I)[CFA-4] (Fig. 5) are in good
agreement with the results from the TGA measurement. The
framework is stable up to 150 °C. Above this temperature the
intensity of the first peak strongly decreases until it completely
disappears at 200 °C. A new crystalline phase of unknown
structure is formed that is stable in the temperature range from
+
such as alkaline or earth alkaline metal ions, as described in
detail in the experimental part. The positions of the disordered
+
solvent molecules and Cu -ions were impossible to resolve and
to refine from the electron density distribution. According to the
crystallographic data there is an electron count of 1312 per unit
+
cell (rest of the electron density), which corresponds to 6 Cu and
2
8.5 DMF molecules in the unit cell of Cu(I)[CFA-4]. Thus, the
composition of the framework is determined as [Cu (tfpb)
5
3
]-
+
(
Cu )∙4.75DMF.
Topology analysis using the TOPOS program26 (see ESI S3)
reveals a new type of the topology: 2,6-c net with stoichiometry
2
50 to 400 °C. The unit cell parameters of the new phase were
(
2-c)3(6-c); 2-nodal net. The chirality of the network results from
the symmetry of the SBU (point group symmetry of the SBU:
).
determined by DICVOL and TREOR 90 program27 based on the
powder pattern collected at 300 °C. Both programs determined a
C
3
quite similar orthorhombic cell with the cell parameters:
6.690 Å, = 15.997 Å, = 8.331 Å,
= 2224.4 Å (DICVOL, M20 = 151, F20 = 30.7 (0.0059, 111))
Thermal and structural stability of Cu(I)[CFA-4] and K[CFA- and
= 16.739 Å, = 16.029 Å, = 8.344 Å, = 2238.8 Å
were determined from TGA and VTXRPD measurements. To (TREOR, M20 = 12, F20 = 23 (0.012035, 73)). Above 400 °C the
a =
1
V
b
c
Thermal analysis and VTXRPD studies
3
3
a
b
c
V
4]
remove the occluded solvent molecules, the samples were dried decomposition of the compound is observed and Cu (PDF no. 4-
in vacuum at 100 °C for 4 h prior to TG measurements. As shown 836) appears as a new crystalline phase.
in Fig. 4, the thermogravimetric profile of Cu(I)[CFA-4] (red Partial exchange of the coordinated DMF molecules in
line) under nitrogen exhibits two weight loss steps. The mass of Cu(I)[CFA-4] by acetonitrile, leads to a sample crystalline up to
the sample is constant up to about 180 °C. In the temperature 400 °C. The VTXRPD of this sample with the composition
4
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3 3
Cu(I)[Cu (tfpb) ]∙2.5CH CN∙0.5DMF (as determined from the adsorption/desorption isotherms of both samples follow type I
Ple Da sae l tdo on n To rt aa nd sj ua sct t mi o an r sg ins
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5
TGA data) are plotted in ESI (Fig. S14).
Variable temperature X-ray powder diffraction studies of maximum uptake achieved at 87 K and p/p =0.99 is 459 cm g
0
K[CFA-4] (Fig. 6) are in good agreement with the results from for Cu(I)[CFA-4] (ESI, Fig. S21) and 541 cm g for K[CFA-
the TGA measurement. The framework is stable up to at least 4] (Fig. 7), corresponding to a total pore volume of 0.58 and
behavior, which is characteristic for microporous solids. The
-
3 -1
-
3 -1
3
-1
2
50 °C. Above this temperature, the decomposition of the 0.69 cm g , respectively (Fig. 7).
compound is observed and Cu (PDF no. 4-836) appears as a new
crystalline phase at 400 °C in the VTXRPD.
Figure 7: Argon adsorption (blue) and desorption (red) isotherms of K[CFA-4] at
7 K. Inset: pore size distribution calculated from these isotherms.
8
Figure 5: VTXRPD plots of Cu(I)[CFA-4] in the range of 50-500°C. The dark
green XRPD pattern is simulated based on single crystal X-ray data. *peaks belong The micropore volume of K[CFA-4] determined at p/p
0
= 0.2 is
to Cu phase (PDF no. 4‐836)
.
3 -1
0
.60 cm g which corresponds well to the value calculated from
3
-1
the crystal structure data (0.64 cm g ). The BET surface area
2
-1
0
determined in the range p/p = 0.1-0.16 is 1431 m g . To
evaluate the pore size distribution of the CFA-4 framework, the
argon sorption isotherms sampled for K[CFA-4] at 87 K were
analysed using non-local density functional theory (NLDFT)28
implementing a carbon equilibrium transition kernel for argon
29
adsorption based on a slit-pore model . The distribution
calculated by fitting the adsorption data reveals micropores with
a diameter in the range of 13-20 Å with a maximum at 17 Å (Fig.
7, inset) which is in good agreement with the crystal structure
data.
Cu(I)[CFA-4], due to the presence of coordinated DMF
2
-
molecules, shows a slightly lower BET surface area of 1324 m g
1
(
0
determined in the range p/p = 0.09-0.12). The high-
temperature phase of Cu(I)[CFA-4] (obtained after heating the
sample at 350 °C in vacuum) exhibits permanent porosity as
2
-1
well, but the specific surface area decreases to 600 m g (for the
isotherm see ESI, Fig. S22).
The isosteric heat of CO adsorption for Cu(I)[CFA-4]
determined from adsorption isotherms measured in the
temperature range 183-203 K (see ESI, Fig. S24) reaches a rather
high value of 52 kJ mol-1 at low loading (< 0.05 mmol g ) and
decreases to typical physisorption values of < 15 kJ mol-1 at >
Figure 6: VTXRPD plots of K[CFA-4] in the range of 50-400°C. *peaks belong
to Cu phase (PDF no. 4‐836)
.
-1
Gas sorption measurements
0
.6 mmol g-1 loading (Fig. 8, green curve). Such behavior hints
Argon gas sorption measurements on Cu(I)[CFA-4] and
K[CFA-4] at 87 K confirm permanent porosity of both
frameworks. Prior to the measurement, the sample of
Cu(I)[CFA-4] was washed with DMF and methanol (K[CFA-
4] with MeOH) and heated at 100 °C in high vacuum for 20 hours
to remove occluded solvent molecules. The resulting argon
at a weak binding of carbon monoxide to the interchannel Cu(I)
cations of Cu(I)[CFA-4]. The copper centres of the SBU of
M[CFA-4] are well-shielded by the CF -groups and not freely
3
accessible to bind small molecules. The amount of active Cu(I)-
sites roughly estimated from the dependence of the isosteric heat
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of CO adsorption on loading (approx. 0.5 mmol g ) corresponds 2132 cm-1 at room temperature (black line) belong to free CO
-1
well to the calculated amount of Cu(I) cations in the channels molecules in the gas phase. The temperature was gradually
-
1
(
0.51 mmol g ). Binding of CO at the interchannel Cu(I) cations decreased in 20 °C steps down to -90 °C. At this temperature, the
is also confirmed by CO sorption measurements on K[CFA-4] gas flow was changed to nitrogen again, followed by the stepwise
-
1
(
see ESI, Fig. S25), revealing an isosteric heat of adsorption of heating up to 50 °C. Below 0 °C, new bands at 2046 cm (with
only 14-16 kJ mol-1 (Fig. 8, red curve). Oxygen adsorption a shoulder at 2055 cm ) and 2157 cm (assigned in Fig. 9 as 1
-1
-1
isotherms for Cu(I)[CFA-4] (see ESI, Fig. S23) reveal nearly and 1a, respectively) were detected. Moreover, the intensity of
-
1
-1
constant physisorption heat of 11-12 kJ mol (Fig. 8, blue curve) the band at 2132 cm as well as for the both new bands 1 and 1a
and thus show that interchannel Cu(I) cations do not bind O
molecules.
2
increase upon cooling process. These bands result from CO
molecules bound to the interchannel Cu(I) ions, as already shown
by enhanced isosteric heat of CO adsorption (Fig. 8). At -60 °C
-
1
a new band at 2127 cm (2) appears, which splits into two bands
at – 90 °C with wavenumbers of 2108 cm-1 (2a) and 2144 cm-1
(
2b), while the band at 2132 cm-1 disappears. We assume that a
second CO molecule binds to the same Cu(I) center at low
temperatures leading to the observed band splitting and
-
1
vanishing of the band at 2132 cm . All these low-temperature
bands (2, 2a and 2b) disappear rapidly after switching from a CO
2
to N -atmosphere while the bands 1 and 1a remain up to 0 °C.
This observation confirms our assumption for a weak binding of
the second CO molecule.
All these recorded bands correspond to the stretch mode of the
I
CO molecules coordinatively bound to Cu -ions and are in good
agreement with literature data of Cu(I)-pyrazolate complexes
-
1
}(CO)]),30 2102 cm-1
(
ν
CO = 2137 cm for [Cu{HB(3,5-(CF
for [Cu{HB(3-C pz
)}(CO)])31
Cu{HB(3,5- Pr pz)
}(CO)]).32
3
)
2
pz
and
3
3
F
7
3
2056 cm-1
for
[
i
2
3
Figure 8: Isosteric heats of CO (green) and O
and CO adsorption in K[CFA-4] (red).
2
(blue) adsorption in Cu(I)[CFA-4]
Photoluminescence and UV-Vis spectroscopy
Solid-state photoluminescence properties of
1,
K[CFA-4] and
Cu(I)[CFA-4] were studied at room temperature. The ligand H
tfpb ( ) exhibits a broad emission peak under excitation at
48 nm (Fig. 10). shows maximum emission at around 340-
50 nm and a smaller emission shoulder at 312 nm. Excitation of
with an emission wavelength of 340 nm leads to a broad
2
-
1
2
1
3
1
excitation spectrum with a main maximum at 245 nm and a side
maximum at 285 nm. Excitation at higher wavelength (290 nm)
results in one emission maximum at 350-355 nm whereas the
shoulder at 312 nm disappears (see ESI Fig. S33). The excitation
of
1
is probably attributed to the π→π* transition of the aromatic
-groups, the ligand is twisted
system. Due to the presence of CF
3
and has no entirely delocalised flat π-system, resulting in two
possible π→π* transitions (corresponding to phenyl- and
pyrazolate-rings). With higher energy (248 nm), excitation of
both transitions is possible, whereas at smaller energy (290 nm)
only one process can be excited. CF
3
-groups at the pyrazolate-
Figure 9: In situ DRIFT spectra of Cu(I)[CFA-4] upon cooling from room
temperature to -90 °C under CO atmosphere and subsequent heating from -90 °C units have
a
strong electron-withdrawing effect. As
a
2
to 50 °C under N atmosphere.
consequence, a higher photon energy is necessary for the
excitation process. The excitation spectrum (λem= 312 nm)
shows only one maximum at 245 nm, whereas a maximum at
In addition, the adsorption of CO in Cu(I)[CFA-4] was studied
2
90 nm disappears (see ESI Fig. S32). Based on these
observations, we presume that the emission at 312 nm results
from the CF -substituted pyrazolate rings of the ligand.
by diffuse reflectance Fourier-transform IR spectroscopy
(
DRIFT) (see Fig. 9). First, the sample was heated up to 160 °C
3
under nitrogen flow. After cooling down to room temperature,
an FT-IR spectrum of the activated Cu(I)[CFA-4] was recorded
under nitrogen. Then, the gas flow was switched to CO and
another spectrum was recorded. The bands at 2171 cm-1 and
Fig. 11 shows photoluminescence spectra for K[CFA-4] (green
line) and Cu(I)[CFA-4] (black line). A broad emission can be
observed for both frameworks in the visible region between
6
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5
00 nm and 750 nm under excitation with the UV light (325 nm
for K[CFA-4]) and 305 nm for Cu(I)[CFA-4]), while the
emission of the ligand disappears. Compared to Cu(I)[CFA-4]
,
the resulting emission band of K[CFA-4] is bathochromically
shifted to lower energies. This shift indicates a stronger Cu···Cu
interaction in Cu(I)[CFA-4] due to the presence of free Cu(I)-
cations in the pores instead of potassium cations. To achieve low-
energy emission, the Cu-Cu distance normally must be less than
I
or close to twice the van der Waals radius of Cu (1.4 Å). The
closest Cu-Cu distance in K[CFA-4] is 3.154 Å and should be
too large to influence the luminescence properties by
intramolecular Cu···Cu interactions. We presume that the
emission here is probably related to a metal-to-ligand charge
transfer. Upon irradiation with the UV light Cu(I) pyrazolates
undergo a metal-to-ligand charge transfer resulting in a charge-
separated excited singlet state. This state can either decay to the
ground state by the emission of slightly red-shifted photons, or
undergo a spin conversion into an excited triplet state, which spectrum (
shows a slow decay (luminescence) to the ground state.33 The
latter transition might be influenced by weak Cu∙∙∙Cu
interactions that typically occur in Cu(I) complexes and
coordination polymers comprising bridging pyrazolate moieties.
Moreover the influence of different solvents on the fluorescence
behaviour of Cu(I)[CFA-4] was investigated (see ESI Fig. S34).
The intensity of the emission maximum strongly depends on the
Figure 10: Solid-state photoluminescence spectra of
Dashed line: excitation spectrum ( 340 nm); Continuous line: emission
248 nm).
1 at room temperature.
em
λ =
ex
λ =
adsorbed solvent molecules.
A
significant fluorescence
quenching can be observed upon addition of nitroaromatic
compounds such as nitrobenzene or dinitrophenol (solution in
methanol). This observation could qualify M[CFA-4] interesting
as a potential material for selective sensing of nitroaromatics.
To demonstrate the sensitivity of M[CFA-4] towards
nitroaromatic compounds, it was exposed to a vapour of
nitrobenzene for various time periods at room temperature.
During the experiment, fluorescence was strongly reduced
within a few minutes (Fig. 12). The emission could be
Figure 11: Solid-state photoluminescence spectra of K[CFA-4] (green) and
regenerated after placing the sample into high vacuum for several Cu(I)[CFA-4] (black) at room temperature. Dashed line: excitation spectrum (λem
20 nm for K[CFA-4] and 610 nm for Cu(I)[CFA-4]); Continuous line: emission
spectrum ( 325 nm for K[CFA-4] and 305 nm for Cu(I)[CFA-4]).
=
6
hours or simply by washing it with ethanol, what makes this
turn-on” and “turn-off” fluorescence to a fully reversible
ex
λ =
“
process.
In literature, several examples of MOFs with such selective
sensing behaviour towards highly electron withdrawing
nitroaromatic compounds have already been reported.34 The
observed fluorescence quenching is attributed to a photoinduced
electron transfer from the excited MOF to the electron deficient
analytes adsorbed on the MOF surface.
Figure 12: Solid-state photoluminescence spectra of Cu(I)[CFA-4] exposed to a
nitrobenzene vapour at room temperature for various time periods (excitation
wavelength 320 nm).
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+
To prove the reactivity of K[CFA-4] and Cu(I)[CFA-4] towards channels of the as-synthesized framework are occupied by Cu
+
+
2+
molecular oxygen, the samples were investigated with UV-vis ions, which can be readily exchanged with K , Cs or Ca . After
+
spectroscopy (see figure 13). Freshly prepared K[CFA-4] (red removal of the solvent, the Cu ions are reactive and can bind
-
1
curve) and Cu(I)[CFA-4] (black curve) show one strong CO with isosteric heat of adsorption of up to 52 kJ mol .
absorption peak at 291 nm in the solid-state UV-vis spectrum. M[CFA-4] remains porous after solvent removal and exhibits
2
-1
Oxidation of Cu(I)[CFA-4] in air is a slow process entailing a the BET surface area of 1591 m g (K[CFA-4]).
color change to dark green. The UV-vis spectrum of the oxidised and M[CFA-4] show interesting fluorescent properties.
1
Cu[CFA-4] (green curve) exhibits a peak shift at small M[CFA-4] shows high porosity, large open pores, a good
wavelength and one additional peak with a maximum at 656 nm, stability towards many solvents and interesting selective and
II
which encompasses the Cu d-d transitions.
sensitive fluorescence behaviour towards nitroaromatics. This
Furthermore, the oxidised Cu[CFA-4] can be reduced to a Cu(I) property, combined with the possibility to exchange metal ions
compound upon heating in DMF at 120 °C for 4 hours (blue in the channels, suggests M[CFA-4] as a promising framework
curve). After four weeks in air, K[CFA-4] shows a UV-vis for the development of new photoluminescent materials and for
spectrum which is similar to the fresh sample
assumption that the SBU of M[CFA-4] is stable against Furthermore, MOFs with fluorinated ligands seem to have high
oxidation, as the copper centres are well-shielded by the CF photostability. Therefore they could be very interesting for
. This leads to the applications in sensor technology.
3
-
groups. This stability against oxidation is another benefit for applications as photocatalysts, for redox reactions or for solar
potential application in photonic research.
fuel production.35
The XRPD patterns of the oxidised and reduced samples (see ESI
Fig. S15) are similar to the freshly prepared, indicating that the
structure remains stable during the oxidation/reduction
sequence. Unfortunately, a single crystal analysis of oxidised
Cu[CFA-4] was not successful due to very weak scattering of
the crystals.
Experimental Section
Materials and general methods
All starting materials were of analytical grade and used as
obtained from commercial sources without further purification.
Thermogravimetric analysis (TGA) was performed with a TGA
Q500 analyser in the temperature range of 25-800 °C in a
-
1
flowing nitrogen gas at a heating rate of 10 K min . NMR
spectra were recorded on a Varian mercury plus 400 high
resolution system; data given in ppm; spectra referenced to the
residual solvent peak. Fourier transform infrared (FTIR) spectra
were recorded with an ATR unit in the range of 4000-400 cm-1
on a Bruker Equinox 55 FT-IR spectrometer. Diffuse reflectance
infrared Fourier-transformed (DRIFT) spectra were recorded
with the same instrument equipped with a Harrick Praying
Mantis I21012 reaction chamber. Energy-dispersive X-ray
spectroscopy (EDX) was performed with a Philips XL-30
scanning electron microscope. Ambient temperature X-ray
powder diffraction (XRPD) patterns were recorded on a Seifert
XRD 3003 TT diffractometer equipped with a Meteor1D
Figure 13: UV-vis spectra of M[CFA-4] at room temperature. Red line: K[CFA-
4]
freshly prepared; black line: Cu(I)[CFA-4] freshly prepared; green line: detector operated at 40 kV, 40 mA, Cu Kα (λ=1.54178 Å) with a
Cu[CFA-4] oxidised; blue line: Cu(I)[CFA-4] reduced.
scan speed of 1s per step and a step size of 0.02 ° in 2θ. Variable
temperature X-ray powder diffraction (VTXRPD) measurements
were collected in the 2θ range of 3-60° with 0.02 ° steps with a
Bruker D8 Advance diffractometer equipped with a Lynxeye
linear position-sensitive detector, a MRI TCPU1 oven, in linear
transmission geometry. The sample was loaded into a capillary
Conclusions
The work reported here describes the synthesis and
characterisation of a novel metal-organic framework M[CFA-4]
assembled from pentanuclear copper(I) secondary building units
(
Hilgenberg) made from special glass no. 10, 0.5 mm diameter
and 0.01 mm wall thickness. The patterns were recorded in a
temperature range from 30 to 500 °C, in the 3-60 ° 2θ range, with
one step per 1 s, and an angular step width of 0.02 ° in 2θ.
Temperature program between measurements: heating rate
Cu I }- and fluorinated bifunctional ligands. To the best of
{
5 6
(pz)
our knowledge, M[CFA-4] represents the first example of a
MOF in which a pentanuclear copper(I)-containing SBU was
found and structurally characterized. This framework
crystallizes in the hexagonal crystal system within the chiral
-
1
(
0.5 °Cs ), then 10 min isothermal. Argon gas sorption
isotherms at 77 K were measured with a Quantachrome
Autosorb-I ASI-CP-8 instrument. Ar (87 K), CO and O sorption
2
space group
3
P6 22 and features channels with a narrowest
isotherms were measured with a BELSORP-max instrument
combined with a BELCryo system. Adsorbed gas amounts are
diameter of 14.3 Å. Due to a negative charge of the lattice, the
8
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ARTICLE
given in cm g [STP], where STP = 101.3 kPa and 273.15 K. Yield: 660 mg (39 %). 1H-NMR (400 MHz, DMSO-d
3
-1
, δ
6
High-resolution mass spectra were recorded with a Q-Tof Ultima (ppm)): 7.40 (s, 4H, CH), 15.39 (s, 2H, NH). 1H-NMR
Mass spectrometer (Micromass) equipped with an ESI source. (400 MHz, acetone-d
, δ (ppm)): 7.55 (s, 4H, CH). 19F-NMR
The elemental composition of molecular ions was verified by (400 MHz, DMSO-d
comparison between experimental and theoretical mass values (400 MHz, acetone-d
and isotopic distributions. Luminescence spectra were acquired (400 MHz, acetone-d
6
, δ (ppm)): -57.65 (s, 12F, CF
, δ (ppm)): -59.68 (s, 12F, CF
3
). 19F-NMR
). 13C-NMR
3
6
6
6
, δ (ppm)): 130.6 (s), 129.4 (s), 121.6 (s),
-
1
using a spectrofluorimeter (FS920, Edinburgh Instruments) 121.3 (q, J= 267 Hz). IR (ν(cm )): 2915; 1540; 1491; 1435;
equipped with a TMS300 monochromator, an S900 single 1304; 1231; 1197; 1136; 981; 847; 767; 655; 552; 488; 432.
+
photon photomultiplier, and a Xe 900 450 W xenon arc lamp at ESI+TOF HRMS m/z 483.0475 ([M+H] , calculated for
+
r. t. The excitation and emission spectra were corrected for the
C
16
H
6
F
12
N
4
+H : 483.0474). The NMR-, IR- and mass- spectra
wavelength-dependent lamp intensity and detector response, of
respectively.
1
are shown in the ESI (S4-10, S17, Table S2).
Synthesis of Cu(I)[Cu
Solvothermal method. A mixture of copper nitrate trihydrate
10 mg; 0.04 mmol) and H -tfpb (10 mg, 0.02 mmol) was
-iodo-3,5-bis(trifluoromethyl)-1H-pyrazole22 was synthesized dissolved in 3 mL DMF (alternative: 3 mL MeOH and 0.0 5ml
from 3,5-bis(trifluoromethyl)-1 -pyrazole via modified 2,6-lutidine) and the solution was placed in a glass tube (10 mL).
iodination procedure, similarly to the literature-described The tube was closed and heated at 120 °C for 3 days and then
procedure for other pyrazole derivatives.36
cooled to room temperature. The precipitate was filtered and
5-bis(trifluoromethyl)-1 -pyrazole (4.00 g; 19.61 mmol), washed with DMF and MeOH and dried at 100 °C under
iodine (2.97 g; 11.76 mmol) and cerium(IV) ammonium nitrate vacuum. This synthesis can be similarly performed at larger
5.37 g; 9.80 mmol) were dissolved in acetonitrile (160 mL). quantities (upscale factor: 20).
5
(tfpb) ] ∙4.75 DMF
3
2
Synthesis of H -tfpb (1)
(
2
4
H
a
3
,
H
(
-
1
After stirring for 30 minutes at room temperature, the brown Yield: 16 mg (43 %). IR (ν(cm )): 2359; 1665; 1498; 1350;
mixture was refluxed for 34 h, cooled to room temperature and 1314; 1218; 1134; 1028; 995; 854; 739; 722; 671; 622; 553; 432.
the solvent was removed with a rotary evaporator. The residue The IR-spectra of Cu(I)[CFA-4] are shown in ESI (S9-11).
was dissolved in ethyl acetate (400 mL) and washed with ice-
cold sodium hydrogen sulphite solution (5 %; 400 mL). The Microwave synthesis. A mixture of copper nitrate trihydrate
aqueous phase was once again extracted with ethyl acetate (10 mg; 0.04 mmol) and H
2
-tfpb (10 mg, 0.02 mmol) was
(
200 mL), before the combined organic phase was washed with dissolved in 3 mL DMF (alternative: 3 mL MeOH and 0.05 ml
brine (200 mL). The solvent was removed under reduced 2,6-lutidine) and the solution was placed in a Pyrex sample tube
pressure and the residue was dried under vacuum affording pure (10 mL). The tube was closed with a cap and placed in a
4
-iodo-3,5-bis(trifluoromethyl)-1H-pyrazole
(5 g;
78 %). microwave synthesizer (CEM, Discover S). The resulting
mixture was heated to 150 °C at 300 W for 20 min and cooled to
room temperature. The precipitate was filtered and washed with
DMF and MeOH and dried at 100 °C under vacuum.
Analytical data correspond to the previously described.22
1
,4-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzene
1.19 g; 3.60 mmol) and 4-iodo-3,5-bis(trifluoromethyl)-1H
pyrazole (2,85 g; 8.64 mmol) were dissolved in 120 mL of 1,2- results for IR- and XRD-measurements as the ones obtained by
dimethoxyethane (DME). solution of CO (1.99 g; the solvothermal method.
4.4 mmol) in water (85 mL) was added. The reaction mixture
(
-
Yield: 9 mg (25 %). This material exhibited the same analytical
A
K
2
3
1
was degassed in vacuum by a freezing method and flooded with Synthesis of Cu(I)[Cu
5
(tfpb)
3 3
]∙2.5CH CN∙0.5DMF
argon. Tetrakis(triphenylphosphine)palladium(0) (416 mg;
Cu(I)[CFA-4]∙2.5CH
extraction of Cu(I)[CFA-4] in acetonitrile (3x2 h) under argon
atmosphere. Finally the sample was dried under argon.
3
CN∙0.5DMF was synthesised by soxhlet
0.36 mmol) was added and the reaction vessel was degassed and
flooded again. After reflux for 48 h and cooling to room
temperature, DME was removed with a rotary evaporator. Water
(
20 mL) and brine (20 mL) were added and extracted with
EtOAc (3x100 mL). The combined organic phase was washed
with brine (150 mL) and dried over MgSO . After removal of the
General synthesis procedure for M[Cu
Ca(0.5))
5 3
(tfpb) ] (M = K, Cs,
4
solvent under reduced pressure, the solid was dried under Cu(I)[CFA-4] (55 mg; 0.03 mmol) was stirred at room
vacuum overnight. Column chromatography on silica gel with a temperature for 2 h in a solution of the corresponding metal
+
+
2+
CHCl
3
: EtOAc (15:1) mixture led to the raw product. nitrate (0.6 mmol for K and Cs , 0.3 mmol for Ca ) in DMF
-pyrazole- (2.5 mL) and H O (0.5 mL). The precipitate was filtered, washed
-yl)benzene was obtained after recrystallization of the raw with water (2x3 mL), DMF (2x3 mL) and MeOH (2x3 mL). This
Analytically pure 1,4-bis(3,5-bis(trifluoromethyl)-1
4
H
2
product from methanol. Single crystals of 1 for X-ray diffraction exchange procedure was repeated three times. The Cu/M molar
experiment were obtained by slow evaporation of the methanolic ratio of the product was determined by energy dispersive X-Ray
solution.
spectroscopy.
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Single-crystal X-ray crystallography
Table 1. Crystal data and structure refinement of 1∙2MeOH and
Cu(I)[CFA-4]
X-ray data for the single crystal structure of 1∙2MeOH were
collected on a Bruker D8 Venture diffractometer. Intensity
measurements were performed using monochromated (doubly
curved silicon crystal) MoKα radiation (0.71073 Å) from a
sealed microfocus tube. Generator settings were 50 kV, 1 mA.
Data collection temperature was -173 °C. APEX2 software was
used for preliminary determination of the unit cell.37
Determination of integrated intensities and unit cell refinement
were performed using SAINT.38 The structure was solved and
refined using the Bruker SHELXTL Software Package.39
Selected crystal data and details of structure refinement for
Compound
1∙2MeOH
Cu(I)[CFA-4]∙4.75
DMF
Empirical formula
Formula
C
18
14
H F
12
N
4
O
2
C
62.25
H45.25 Cu
6 36 16.75
F N
O
4.75
C H F N ,
16
6
12
4
Cu(I)[Cu (C H F N ) ]
5
16
4
12
4 3
2
(CH
3
OH)
3 7
∙4.75 (C H NO)
-
1
Mr/g mol
546.33
100(2)
0.71073
Monoclinic
C2/m (no. 12)
8.8990(5)
14.7907(7)
8.9987(8)
90
111.494(2)
90
1102.06(13)
2
1.646
0.177
548
2.43 to 25.08
12273
1026
0.0491
0.945
2169.14
295(2)
0.88561
Hexagonal
T/K
Wavelength/Å
Crystal system
Space group
a/Å
b/Å
c/Å
α/°
β/°
3
P6 22 (no. 182)
23.630(5)
23.630(5)
41.390(5)
90
90
120
20015(6)
6
1.080
1.856
6432
2.23 to 36.16
81573
15739
0.0833
0.983
0.490(13)
0.0506
1
∙2MeOH are provided in Table 1.
X-ray data for the single crystal structure of Cu(I)[CFA-4] were
collected at 295 K using synchrotron radiation with energy of 14
keV (λ = 0.88561 Å) on BESSY MX BL14.2 beamline of
Helmholtz Zentrum Berlin für Materialien und Energie.40 The
single crystal was transferred to a glass capillary with some
amount of solvent. The φ-scans with oscillation range of 1° were
used for data collection. The data were integrated and scaled with
the XDS software package.41 The structure was solved using
direct methods with the help of SHELXS-97 and refined by full-
matrix least squares techniques using SHELXL Version
γ/°
V/Å
3
Z
D
μ/mm
-3
c
/g cm
-
1
F(000)
θ Range/º
Refls. collected
Refls. unique
R(int)
GooF
Flack parameter
016/1.42 Cu(I)[CFA-4] was refined as a racemic twin, with the
2
-
inversion matrix TWIN 100 0 10 00 1 and the BASF
−
−
−
a
R
1
(I>2σ(I)]
0.0286
0.0720
0.334 and -0.221
coefficient 0.49. Non-hydrogen atoms were refined with
anisotropic temperature parameters. The hydrogen atoms were
positioned geometrically and refined using a riding model. The
positions of the disordered solvent molecules and Cu(I)-ions
were impossible to resolve and to refine from the electron density
distribution. The SQUEEZE procedure implemented in the
program PLATON24 was used and an electron count of 1312 per
unit cell (rest of the electron density) was calculated. This value
corresponds to 6 Cu(I)-ions and 28.5 DMF molecules in the unit
cell of Cu(I)[CFA-4]. Thus, the composition of the framework
b
wR
2
(all data)
0.1656
0.549 and -0.515
Largest diff. peak
-
3
and hole/Å
a
b
2
2
2
1/2
R
1
= Σ||F |-|F ||/Σ|F
0
c
0
|; wR
2
= Σ[w(F
0
-Fc )2]/Σ[w(F
0
)2]
.
Acknowledgements
Financial support by the DFG (Priority Program SPP 1362
“Porous Metal-Organic Frameworks”) is gratefully
acknowledged. We thank HZB for the allocation of synchrotron
radiation beamtime.
-
+
was determined as [Cu
crystallographic data for the structures
Cu(I)[Cu (tfpb) ∙4.75DMF reported in this paper have been
5
(tfpb)
3
] (Cu )
・
4.75 DMF. Complete
1∙2MeOH and
5
3
]
deposited in the CIF format with the Cambridge Crystallographic
Data Center, 12 Union Road, Cambridge CB21EZ, UK as
supplementary publication no. CCDC 1532837 and 1532600,
respectively.
Notes and references
a
Augsburg University, Institute of Physics, Chair of Solid State and
Materials Chemistry, Universitaetsstrasse 1, 86159 Augsburg, Germany.
E-mail: dirk.volkmer@physik.uni-augsburg.de; Fax: +49 (0)821 598 5955;
Tel: +49 (0)821 598 3006
b
Department of Inorganic Chemistry, Dresden University of Technology,
Bergstrasse 66, 01062 Dresden, Germany
†
Electronic Supplementary Information (ESI) available: Crystallographic
data and topology analysis, NMR-, IR-, UV-Vis-, Mass- and
Photoluminescence spectra, gas sorption measurements, EDX, TGA and
VTXRPD data for CFA-4. For ESI and crystallographic data in CIF or
other electronic format see DOI: 10.1039/b000000x/
1
0 | J. Name., 2012, 00, 1‐3
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1
10
(
a) M. P. Suh, H. J. Park, T. K. Prasad and D.-W. Lim, Chem. Rev., 2012,
12, 782-835; (b) I. Senkovska and S. Kaskel, Microporous and
D.-S. Zhang, Z. Chang, Y.-F. Li, Z.-Y. Jiang, Z.-H. Xuan, Y.-H.
Zhang, J.-R. Li, Q. Chen, T.-L. Hu and X.-H. Bu, Sci. Rep., 2013,
312.
3,
1
3
Mesoporous Materials, 2008, 112, Issues 1-3, 108-115; (c) L. J.
Murray and M. Dinca, J. R. Long, Chem. Soc. Rev., 2009, 38, 1294-
1
1
C.G. Piscopo, F. Trapani, A. Polyzoidis, M. Schwarzer, A. Pace and S.
Loebbecke, New J. Chem., 2016, 40, 8220-8224.
12
1
314; (d) H. Furukawa, K. E. Cordova, M. O´Keeffe and O. M. Yaghi,
M. C. Das, S. C. Xiang, Z. J. Zhang and B. L. Chen, Angew. Chem. Int.
Science, 2013, 341, 974.
Ed., 2011, 50, 10510-10520.
2
(
a) J. An, S. J. Geib and N. L. Rosi, J. Am. Chem. Soc., 2009, 131, 8376-
13
(
a) Z. Hu, B. J. Deibert and J. Li, Chem. Soc. Rev., 2014, 43, 5815-5840;
b) Y. Li, S. S. Zhang and D. T. Song, Angew. Chem. Int. Ed., 2013,
8
377; (b) N. P. E. Barry, O. Zava, P. J. Dyson and B. Therrien, Chem.
(
Eur. J., 2011, 17, 9669-9677; (c) P. Horcajada, C. Serre, G. Maurin,
N. A. Ramsahye, F. Balas, M. Vallat- Regí, M. Sebban, F. Taulelle and
G. Férey, J. Am. Chem. Soc., 2008, 130, 6774-6780; (d) E. Quartapelle
Procopio, S. Rojas, N. M. Padial, S. Galli, N. Masciocchi, F. Linares,
5
2
, 710-713; (c) D. Liu, K. Lu, C. Poon and W. B. Lin, Inorg. Chem.
,
2
014, 53, 1916-1924.
14
15
S. E. Miller, M. H. Teplensky, P. Z. Moghadam and D. Fairen-Jimenez,
Interface Focus, 2016, : 20160027.
6
D. Miguel, J. E. Oltra, J. A. R. Navarro and E. Barea, Chem. Commun.
011, 47, 11751-11753.
,
(
a) A. Barba-Bon, A. M. Costero, S. Gil, M. Parra, J. Soto, R. Martínez-
Máñezac and F. Sancenón, Chem. Commun., 2012, 48, 3000-3002; (b)
A. M. Costero, J. V. Colomer, S. Gil and M. Parra, Eur. J. Org. Chem.,
2
3
(
a) L. E. Kreno, K. Leong, O. K. Farha, M. Allendorf, R. P. Van Duyne
and J. T. Hupp, Chem. Rev., 2012, 112, 1105-1125; (b) O. Shekhah, J.
Liu, R. A. Fischer and Ch. Wöll, Chem. Soc. Rev., 2011, 40, 1081-
2
009, 3673-3677.
16
17
18
19
20
21
22
23
24
J. An, C. M. Shade, D. A. Chengelis-Czegan, S. Petoud, N. L. Rosi, J.Am.
Chem. Soc, 2011, 133, 1220-1223.
1
106; (c) S. T. Meek, J. A. Greathouse and M. D. Allendorf, Adv.
Mater., 2011, 23, 249-267.
B. Chen, L. Wang, Y. Xiao, F. R. Fronczek, M. Xue, Y. Cui and G. Qian,
Angew. Chem. Int. Ed., 2009, 48, 500-503.
4
(
a) J. Teufel, H. Oh, M. Hirscher, M. Wahiduzzaman, L. Zhechkov, A.
Kuc, T. Heine, D. Denysenko and D. Volkmer, Adv. Mater., 2013, 25
,
J. A. Hurd, R. Vaidhyanathan, V. Thangadurai, C. I. Ratcliffe, I. L.
6
35-639; (b) H. Oh, I. Savchenko, A. Mavrandonakis, T. Heine and M.
Moudrakovski and G. K. H. Shimizu, Nat. Chem., 2009, 1, 705-710.
Hirscher, ACS Nano, 2014, 8, 761-770; (c) E. Quartapelle Procopio, F.
P. Schmieder, D. Denysenko, M. Grzywa, O. Magdysyuk and D.
Volkmer; Dalton Trans.; 2016, 45, 13853-13862.
Linares, C. Montoro, V. Colombo, A. Maspero, E. Barea and J. A. R.
Navarro, Angew. Chem. Int. Ed., 2010, 49, 7308-7311; (d) P. D. C.
Dietzel, V. Besikiotis and R. Blom, J. Mater. Chem., 2009, 19, 7362-
M. Grzywa, D. Denysenko, A. Schaller, A. Kalytta-Mewes and D.
Volkmer, CrystEngComm., 2016, 18, 7883-7893.
7
370.
a) D. Farrusseng, S. Aguado and C. Pinel, Angew. Chem., 2009, 121
638-7649; (b) J. Liu, L. Chen, H. Cui, J. Zhang, L. Zhang and C.-Y.
D. Denysenko, M. Grzywa, J. Jelic, K. Reuter and D. Volkmer, Angew.
Chem. Int. Ed., 2014, 53, 5832-5836.
5
(
,
7
A. Maspero, G. B. Giovenezana, D. Monticelli, S. Tagliapietra, G.
Palmisano and A. Penoni, J. Fluorine Chem., 2012, 139, 53-57.
M. Kleinwächter, L. Vendier, C. Dinoi, M. Etienne, Dalton Trans., 2013,
Su, Chem. Soc. Rev., 2014, 43, 6011-6061; (c) M. Tonigold, Y. Lu, A.
Mavrandonakis, A. Puls, R. Staudt, J. Möllmer, J. Sauer and D.
Volkmer, Chem. Eur. J., 2011, 17, 8671-8695.
42, 10102
6
7
(
(
a) C. Yang, X. Wang and M. A. Omary, J. Am. Chem. Soc., 2007, 129
,
A. L. Spek, Acta Cryst., 2015. C71, 9–18.
1
5454-15455; (b) C. Yang, X. Wang and M. A. Omary, Angew. Chem.
25
26
27
Quantachrome Autosorb, Version 1.56, 2009.
V. A. Blatov, IUCr CompComm Newsletter, 2006,
Int. Ed., 2009, 48, 2500-2505.
7
, 4–38.
a) Handbook of Fluorous Chemistry (Eds.: J. A. Gladysz, D. P. Curran
and I. T. Horváth), Wiley-VCH, Weinheim, Germany, 2004; (b). I. T.
Horváth and J. Rabai, Science, 1994, 266, 72-75; (c) P. T. Nyffeler, S.
G. Durón, M. D. Burkart, S. P. Vincent and C.-H. Wong, Angew.
Chem. Int. Ed., 2005, 44, 192-212.
P.-E. Werner, L. Eriksson, M. Westdahl, J. Appl. Crystallogr., 1985, 18
67-370.
,
3
28
29
30
31
32
P. I. Ravikovitch and A. V. Neimark, Colloids Surf., 2001, 187, 11.
J. Jagiello and M. Thommes, Carbon, 2004, 42, 1227.
H. V. R. Dias and H.-L. Lu, Inorg. Chem., 1995, 34, 5380-5382.
H. V. R. Dias and H.-J. Kim, Organometallics, 1996, 15, 5374-5379.
8
9
M. Pagliaro and R. Ciriminna, J. Mater. Chem., 2005, 15, 4981-4991.
T.-H. Chen, I. Popov, W. Kaveevivitchai, Y.-C. Chuang, Y.-S. Chen, A.
J. Jacobson and O. Š. Miljanić, Angew. Chem., 2015, 127, 14108-
K. Fujisawa, T. Ono, Y. Ishikawa, N. Amir, Y. Miyashita, K. Okamoto
and N. Lehnert, Inorg. Chem., 2006, 45, 1698-1713.
1
4112.
33
(
a) N. Armaroli, G. Accorsi, F. Cardinali, A. Listorti, in Curr Chem, ed.
V. Balzani, S. Campagna, Springer-Verlag, Berlin Heidelberg,
This journal is © The Royal Society of Chemistry 20xx
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ARTICLE
Journal Name
3
6
M. I. Rodriguez-Franco, I. Dorronsoro, A. I. Hernández-Higueras and G.
Antequera, Tetrahedron Letters, 2001, 42, 863-865.
APEX2 Version 2011.6, Bruker AXS Inc.
3
3
3
7
8
9
SAINT Version 8.32B, Bruker AXS Inc., 2013.
XL Version 2013/3; G. M. Sheldrick, Acta Crystallogr., Sect. A:
Fundam. Crystallogr., 2008, 64, 112.
4
0
U. Mueller, N. Darowski, M. R. Fuchs, R. Forster, M. Hellmig, K. S.
Paithankar, S. Puhringer, M. Steffien, G. Zocher and M. S. Weiss, J.
Synchrotron Rad., 2012, 19, 442-449.
4
4
1
2
W. Kabsch, J. Appl. Crystallogr., 1988, 21, 67.
G. M. Sheldrick, Acta Cryst, 2015, C71, 3–8.
Germany, 2007, 280, pp. 69–115; (b) P. C. Ford, W. Cariati and J.
Bourassa, Chem. Rev., 1999, 99, 3625.
3
4
(
a) Y.-N. Gong, L. Jiang and T.-B. Lu, Chem. Commun., 2013, 49,
1
1113-11115; (b) B Gole, A. K. Bar and P. S. Mukherjee, Chem. Eur.
J., 2014, 47, 12137-12139; (c) S.-R. Zhang, D.-Y. Du, J.-S. Qin, S.-J.
Bao, S.-L. Li, W.-W. He, Y.-Q. Lan, P. Shen and Z.-M. Su, Chem. Eur.
J., 2014, 20, 3589-3594; (d) S. L. Jackson, A. Rananaware, C. Rix, S.
V. Bhosale and K. Latham,Cryst. Growth Des., 2016, 16, 3067-3071.
3
5
A. Dhakshinamoorthy, A. M. Asiri and H. García, Angew. Chem. Int.
Ed., 2016, 55, 5414-5445.
1
2 | J. Name., 2012, 00, 1‐3
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