Manometric real-time studies of the mechanochemical synthesis of zeolitic imidazolate frameworks

Article abstract of DOI:10.1039/c9sc05514b

We demonstrate a simple method for real-time monitoring of mechanochemical synthesis of metal-organic frameworks, by measuring changes in pressure of gas produced in the reaction. Using this manometric method to monitor the mechanosynthesis of the zeolitic imidazolate framework ZIF-8 from basic zinc carbonate reveals an intriguing feedback mechanism in which the initially formed ZIF-8 reacts with the CO₂ byproduct to produce a complex metal carbonate phase, the structure of which is determined directly from powder X-ray diffraction data. We also show that the formation of the carbonate phase may be prevented by addition of excess ligand. The excess ligand can subsequently be removed by sublimation, and reused. This enables not only the synthesis but also the purification, as well as the activation of the MOF to be performed entirely without solvent.

Full text of DOI:10.1039/c9sc05514b

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DOI: 10.1039/C9SC05514B
ARTICLE
Manometric real-time studies of the mechanochemical synthesis
of zeolitic imidazolate frameworks†
a
b
c
c
d
e
Ivana Brekalo , Wenbing Yuan , Cristina Mottillo , Yuneng Lu , Yuancheng Zhang , Jose Casaban , K.
Received 00th January 20xx,
Accepted 00th January 20xx
a
d
f
f
f
Travis Holman* , Stuart L. James* , Frédéric Duarte , P. Andrew Williams , Kenneth D. M. Harris*
and Tomislav Friščić*
c
DOI: 10.1039/x0xx00000x
We demonstrate a simple method for real-time monitoring of mechanochemical synthesis of metal-organic frameworks, by
measuring changes in pressure of gas produced in the reaction. Using this manometric method to monitor the
mechanosynthesis of the zeolitic imidazolate framework ZIF-8 from basic zinc carbonate reveals an intriguing feedback
2
mechanism in which the initially formed ZIF-8 reacts with the CO byproduct to produce a complex metal carbonate phase,
the structure of which is determined directly from powder X-ray diffraction data. We also show that the formation of the
carbonate phase may be prevented by using excess ligand, enabling the rational development of first design leading to
completely solvent-free and quantitative mechanochemical formation of ZIF-8 on a 90 gram scale, with excess ligand
removed by sublimation.
understood, and it was not until 2013 that methodologies for
Introduction
direct, in situ monitoring of such transformations were
reported, using powder X-ray diffraction (PXRD) and/or Raman
1
Mechanochemical reactions have developed from a laboratory
curiosity to a viable alternative to conventional solution-based
chemistry, enabling room-temperature reactions without bulk
2
3
solvents, improved or previously unknown reactivity, and
4
routes to molecules and materials otherwise difficult to access.
Ball milling, twin screw extrusion, and accelerated aging have
been applied successfully for the synthesis of diverse Metal-
Organic Frameworks (MOFs), including carboxylate-based
HKUST-1,8 MOF-74 and IRMOF materials,
imidazolate frameworks (ZIFs), and zirconium-based UiO- and
NU-systems.13 Importantly, mechanochemistry permits simple,
room-temperature and solvent-free assembly of MOFs from
metal oxides, carbonates or other basic salts: reagents that are
preferred for industrial synthesis, but are often not usable due
to poor solubility.1
5
6
7
9
10,11
zeolitic
1
2
4-16
Despite the rapid growth of applications of
mechanochemistry in chemical and materials synthesis, the
underlying reaction mechanisms and kinetics remain poorly
a. Department of Chemistry, Georgetown University, 20057 Washington, D.C.,
U.S.A. E-mail: kth7@georgetown.edu
b.
School of Chemical Engineering and Technology, Hainan University, 570228,
Haikou, China
c.
Department of Chemistry, McGill University, H3A 0B8, Montreal, Quebec, Canada
E-mail: tomislav.friscic@mcgill.ca
School of Chemistry, Queen’s University Belfast, BT7 1NN, Belfast, U.K. E-mail:
d.
S.James@qub.ac.uk
MOF Technologies, BT7 1NF, Belfast, U.K.
School of Chemistry, Cardiff University, CF10 3AT, Cardiff, U.K. E-mail:
e.
f.
Figure 1. a) Reaction scheme for mechanochemical synthesis of ZIFs from basic zinc
HarrisKDM@cardiff.ac.uk
†
Footnotes relating to the title and/or authors should appear here.
carbonate and an imidazole. Symbol for mechanochemical conditions adopted from
Electronic Supplementary Information (ESI) available: Crystallographic data (also
CCDC deposition code 1942361), experimental and analytical details. See
DOI: 10.1039/x0xx00000x
Righmire and Hanusa.1d b) Structure of zni-Zn(Im)
(CSD code IMIDZB03), c) structure of
2
(CSD code KAMZUV), d) time-dependent pressure profiles (stars mark
2
SOD-Zn(MeIm)
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end of milling) and e) correlation between pressure yield and TGA yield in the model
milling reactions Mod-(1-5) in which solids CaCO and MoO yield solid CaMoO and CO
3 3 4 2
gas (see ESI).
Co(Im)
2
(see ESI). Importantly, we also show that manometric
View Article Online
DOI: 10.1039/C9SC05514B
monitoring of reaction progress, based on changes of pressure
(and temperature) inside the reaction vessel due to release of
CO , allowed the discovery of a feedback mechanism that
2
spectroscopy.17 However, other simpler methods have been
employed for monitoring mechanochemical reactions, in cases
where direct acquisition of structural data is not required. One
of these methods is monitoring the pressure and temperature
of a gaseous reactant or product in a reaction vessel of constant
volume - manometric monitoring. This method appears
particularly attractive as the body of work on mechanochemical
creates a complex metal imidazolate carbonate side product.
Identification of this mechanism enabled us to circumvent side
product formation and design the first mechanochemical multi-
gram synthesis of ZIF-8 without using any liquids in either the
synthesis or activation step.
1
8,19
reactions involving gases
is increasing, and so is the
Results and Discussion
accessibility of equipment for handling gas pressure under
mechanochemical conditions. It is therefore surprising that Model reactions
there are comparably few reports on manometric monitoring of
mechanochemical reactions, the vast majority of which involve
purely inorganic systems. For example, the high-pressure
Reactions were conducted in a Retsch PM400 planetary mill,
TM
using PM GrindControl
vessels equipped for real-time
measurement and recording of pressure and temperature
inside the vessel. To establish the chemical significance of
pressure measurements, we first investigated a simple model
2
0
21
mechanochemical synthesis of inorganic hydrides , nitrides ,
2
2
or oxides has been monitored through the uptake of H
O gas, respectively, and the synthesis of SnO and BaWO
2 4
2
, N
2
or
24
2
3
reaction of solid CaCO
equimolar amounts, is expected to yield CaMoO
equivalent of CO gas (Figure 1d-e). In a typical experiment, 5.9
g of MoO (0.04 mol) and 4.1 g of CaCO (0.04 mol) were milled
3
with MoO
3
which, upon milling in
from carbonate precursors was monitored by measuring the
increase in the pressure of released CO . Very recently, the
Borchard group used monitoring of evolved HCl gas as a way to
4
and one
2
2
3
3
2
5
follow the course of a mechanochemical Scholl reaction, and
thermally-induced increase in gas pressure was used to detect
at a frequency of 350 rpm. Reaction conditions (milling time and
media) were varied to achieve a broad range of yields (see ESI).
During milling, pressure in the reaction vessel increased in a
monotonic fashion, aside from a small pressure drop at the end
of the milling time associated with a rapid temperature drop.
Reaction conversions were calculated both from the final
pressure in the reaction vessel and from subsequent
thermogravimetric analysis (TGA) of the milled samples, giving
values in excellent agreement (Figure 1e).
2
6
highly exothermic reactions, demonstrating the potential for
a broader applicability of manometric monitoring in studies of
mechanochemistry.
Surprisingly, this approach has not yet been used to monitor
mechanochemical synthesis of MOFs, despite the wide
applicability and overwhelming interest for better
understanding of these reactions. We hypothesized that
mechanochemical synthesis of MOFs could be studied by
manometric monitoring if metal carbonates were used as the Reactions of basic zinc carbonate and imidazole
metal source, releasing carbon dioxide and water. It was
Having established that monitoring the increase of gas pressure
during milling can be used to quantify the extent of reaction, we
explored the neat grinding (NG) mechanochemical reaction of
previously shown that metal carbonates can be used in
2
7
mechanochemical synthesis of MOFs and, more broadly,
2
8
coordination polymers and discrete metal-organic complexes.
imidazole (HIm) with basic zinc carbonate, [ZnCO
3 2 2 3
] [Zn(OH) ]
Basic zinc carbonate, basic copper(II) carbonate, as well as rare
earth metal carbonates have been used to synthesize diverse
carboxylate-based MOFs, including pillared MOFs and HKUST-
(ZnCarb) in a Zn:Im ratio of 1:2. Pressure inside the vessel rose
slowly during the first 5 min of milling, after which it rapidly
increased, reaching a maximum within ca. 12 min (Figure 2a). A
significantly higher reaction rate was observed if the reaction
2
7
1
.
Moreover, the archeypal zeolitical imidazolate framework
5
ZIF-8 has been synthesized by twin screw extrusion from 2-
methylimidazole and basic zinc carbonate.
2
9
was done by liquid-assisted grinding (LAG, milling in the
presence of a liquid additive) or by ion- and liquid-assisted
grinding (ILAG, milling in the presence of a liquid additive and a
Here we provide proof-of-concept of a manometric method
to monitor the course of mechanochemical MOF formation by
milling. Manometric monitoring allows observation of distinct
differences in reactivity using three techniques: neat milling,
3
0
catalytic amount of a salt ). Specifically, the addition of 3 mL of
ethanol (EtOH) to 13.5 g of the reaction mixture (liquid-to-solid
2
9
ratio η=0.22 μL/mg ) led to a rapid increase of pressure
immediately upon the onset of milling, reaching a maximum in
ca. 10 min (Figure 2a). Similar observations were made for ILAG,
conducted with addition of 3 mL of EtOH and 400 mg (10 mol%
2
9
liquid-assisted grinding (LAG) and ion- and liquid-assisted
(
ILAG).30 Specifically, we show how the use of a metal
5
,27,28
carbonate
precursor can enable monitoring of the
mechanochemical syntheses of MOFs, namely the zni-topology
4 3
with respect to zinc) of NH NO as the salt additive (Figure 2a).
3
1
zinc imidazolate and the sodalite (SOD) topology zinc 2-
methylimidazolate32 MOF (ZIF-8/MAF-4, sold as Basolite Z1200
or Porolite Z8, Figures 1a-c). We also provide a preliminary
demonstration that the methodology is applicable to an
analogous cobalt(II) system, leading to a mixture of cag- and zni-
2
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ZnCarb and HMeIm (15 g scale), led to a monotonic increase in
View Article Online
DOI: 10.1039/C9SC05514B
vessel pressure over the first 10 min milling, followed by a slow
decrease (Figure 3a). The appearance of such a temporary peak
in reaction vessel pressure was observed in all repeated
experiments. PXRD analysis of the reaction products after 15
min milling revealed only Bragg reflections of ZIF-8. However,
after 1 h milling, PXRD analysis of the products revealed
additional peaks, consistent with a complex metal carbonate (1)
3
4
of unknown structure, previously reported to form upon
exposure of ZIF-8 to moist CO . Close examination of the
H C cross-polarization magic angle spinning (CP-MAS) solid-
2
1
13
state nuclear magnetic resonance (SSNMR) spectrum of the
product after 15 min milling shows signals of 1, indicating that
it is present in the mixture, though undetected by PXRD (see
Figure S14). Similar behavior was observed with LAG, conducted
by adding 3 mL of EtOH to 15 g of reaction mixture (η=0.20
μL/mg). In this case, the reaction vessel pressure also exhibited
an early maximum, and slowly diminished over time. Analysis
by PXRD again revealed the formation of ZIF-8, along with low-
Figure 2. a) Time-dependent reaction vessel pressure profiles for the mechanochemical intensity reflections of 1.
reactions of basic zinc carbonate [ZnCO
LAG (ethanol, dashed line), and ILAG (ethanol, NH
experimental PXRD patterns of the reagents and products of milling syntheses of zni-
3
]
2
[Zn(OH)
2
] with imidazole by NG (solid line),
These observations suggest that the mechanochemical
reaction of basic zinc carbonate and HMeIm proceeds in two
stages, first yielding ZIF-8 and producing an increase in the
4
NO , dotted line) milling; b)
3
Zn(Im)
Zn(Im)
2
from basic zinc carbonate and imidazole, and the calculated PXRD pattern of zni-
(CSD code IMIDZB03).
reaction vessel pressure due to CO
however, leads to absorption of the nascent CO
and further reaction between ZIF-8 and the H
2
evolution. Further milling,
gas by ZIF-8
O and CO
2
2
2
2
The LAG and ILAG reactions led to significantly higher final
reaction pressures compared to neat milling, indicating
conversions of 87% for LAG and ILAG and 64% for neat milling,
after accounting for the vapour pressure of EtOH and solubility
byproducts, which yields the carbonate phase 1 and is
accompanied by a decrease in the reaction vessel pressure. This
proposed reaction pathway was also verified by analogous
experiments in a shaker mill, the smaller scale of which enabled
more thorough sampling of the reaction mixture. Analysis of
PXRD patterns of the LAG reaction mixture after 5 min and 10
min milling revealed that ZIF-8 was the only reaction product,
while Bragg reflections of 1 were clearly visible after 30 min
of CO
PXRD immediately after milling revealed that the zni-topology
framework zni-Zn(Im) was the only crystalline component
Figure 1b), suggesting that conversion was, in fact, complete.
2
in EtOH (see ESI). However, analysis of the products by
2
(
Moreover, TGA of the milling products, conducted after
washing with ethanol, provided an excellent match for pure
Zn(Im) , without any residual zinc carbonate reactant. The TGA
2
and PXRD results strongly indicate that all three milling
approaches result in quantitative conversion of reactants to zni-
(Figure S21). Such reaction behavior was not greatly affected by
the choice of milling liquid (water, methanol or isopropanol),
although it seems that the use of sterically more demanding
milling liquids leads to less carbonate byproduct (Figure S22).
2
Zn(Im) , in contrast to reaction vessel pressure measurements.
As a potential explanation for the discrepancy between
pressures measured for neat milling and for reactions in the
presence of a liquid phase, we consider that some of the CO
2
3
3
gas might be retained in the pores of zni-Zn(Im)
2
formed by
neat grinding. In the case of LAG or ILAG reactions, the pores of
zni-Zn(Im) might also be occupied by the liquid additive,
reducing such entrapment of CO
2
2
.
Reactions of basic zinc carbonate and 2-methylimidazole
Reactions in a 1:2 stoichiometric ratio of ZnCarb and HMeIm
Next, we investigated reaction vessel pressure changes for the
reaction of basic zinc carbonate and 2-methylimidazole
(HMeIm), expected to yield the popular sodalite (SOD)
topological form of Zn(MeIm) (ZIF-8). The reaction vessel
2
pressure profile was very different from that observed with
HIm. Milling the two reactants in a 1:2 stoichiometric ratio of
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Crystal structure determination of 1 from PXRD data
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DOI: 10.1039/C9SC05514B
In order to substantiate that a carbonate phase is indeed
formed on reaction of ZIF-8 and moist CO , crystal structure
determination of 1 was carried out directly from PXRD data
recorded on a sample prepared (independently) by exposing a
suspension of ZIF-8 in water to a stream of CO gas. The PXRD
2
3
5
2
data were recorded in transmission mode on a Bruker D8
instrument (Ge-monochromated CuKα1), and revealed that the
sample contained a small residual amount of ZIF-8 together
3
6
with 1. The PXRD data for 1 were indexed using the ITO code
3
7
in the program CRYSFIRE, giving a unit cell with orthorhombic
metric symmetry (a = 10.54 Å, b = 12.06 Å, c = 4.70 Å; V = 596.5
3
Å ). The space group was assigned as Pba2, with two formula
units of Zn
using the Le Bail method in the GSAS program gave a good
quality of fit (Rwp = 3.99%, R = 2.81%; Figure S25), and the
2 2 3
(MeIm) CO in the unit cell (Z = 2). Profile fitting
3
8
p
refined unit cell parameters were used in the subsequent
structure solution calculation, which was carried out using the
direct-space genetic algorithm technique in the program
3
9
EAGER. The best structure solution was then used as the
starting model for Rietveld refinement, carried out using the
3
8
GSAS program, giving a good final Rietveld fit (Rwp = 4.97%, R
3.37%; Figure 3c) to the PXRD data, very close to the quality
of the Le Bail fit, with the following refined parameters: a =
p
=
1
Å .
0.5295(3) Å, b = 12.0539(4) Å, c = 4.6928(1) Å, V = 595.62(4)
3
-
In 1, each zinc cation is bonded tetrahedrally to two MeIm
2
-
and two CO
3
anions. The 2-methylimidazolate anions bridge
the zinc cations into one-dimensional ribbons, which are then
connected into sheets by carbonate anions (Figure 3d). The
2
-
CO
3
anions display two modes of coordination: one of the
oxygen atoms is doubly coordinated and connects zinc atoms
within a single sheet, while the other two oxygen atoms are
singly coordinated to two neighbouring zinc atoms from a
second sheet (Figure 3e). In this way, the carbonate serves both
as a building block for the sheets and as a perpendicular strut
stacking the sheets together into a three-dimensional
framework.
Reactions in a 1:3 stoichiometric ratio of ZnCarb and HMeIm
The manometric observation of the reaction between basic zinc
carbonate and HMeIm thus revealed a parasitic process that
converts the target ZIF-8 into a complex carbonate 1. The
composition of 1 suggests that the process could involve a
-
reaction in which MeIm anions are replaced by carbonates:
2
2 2 2 2 3
Zn(MeIm) + H O + CO  Zn(MeIm) ·ZnCO + 2HMeIm (Eq. 1)
The proposed equation suggests that formation of 1 may be
avoided by using excess HMeIm, both as a pore-filling agent to
bottom: NG reactions; Zn:HMeIm = 1:2 (15 min and 1 hr), Zn:HMeIm = 1:3 (1 hr), ethanol minimize access of CO3 to zinc centers, and as a means to take
Figure 3. a) Time-dependent reaction vessel pressure profiles and b) PXRD patterns for
the different syntheses of SOD-Zn(MeIm) from basic zinc carbonate and HMeIm. Top to
2
2
-
LAG reactions; Zn:HMeIm = 1:2 (15 min and 1 hr). Stars indicate peaks of 1 in the reaction
mixtures. Structure determination of complex carbonate 1 from PXRD data: c) the final
fit obtained in the Rietveld refinement, and views of the structure of 1 along d) the c-axis
and e) the a-axis.
advantage of Le Chatelier’s principle to shift the equilibrium
towards the formation of ZIF-8.
Manometric monitoring of the neat milling reaction of
ZnCarb with three equivalents of HMeIm per zinc revealed a
4
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continuous increase in reaction vessel pressure, which methanol. The results (see ESI) overall show sloVwieewrArrtieclaecOtniloinne
plateaued after ca. 50 min milling (Figures 3a, S13). PXRD kinetics than in the analogous reactiDoOnI: 1u0s.1i0n3g9/Cb9aSsCic055z1in4Bc
analysis of the sample after 1 hr milling revealed ZIF-8 as the carbonate, but again demonstrate significantly faster reactivity
only reaction product, with no observable Bragg reflections due in the case of LAG; thus, after 90 min milling, pressure-based
to 1 (Figure S12). After washing with EtOH, TGA of the product measurements indicate a reaction conversion of 42% for neat
gave a residue of 36% (Figure S18), which is consistent with the milling and 92% for LAG. Analysis of the products by PXRD after
ZnO residue expected for pure ZIF-8 (36.4%). Furthermore, the 90 min milling indicates qualitatively different behavior
1
13
H C CP-MAS SSNMR spectrum of the product after 15 min compared to the zinc-based system: neat milling leads to a
milling showed only ZIF-8 peaks, and no signals due to 1 (Figure predominantly amorphous material, while LAG produces a
S20). Similarly, PXRD analysis of analogous LAG reactions with mixture of products, including zni-Co(Im) and the less dense
excess HMeIm in a shaker mill showed no evidence for the cag-Co(Im) framework. More detailed studies on this system
2
2
presence of 1 even after 30 min milling with methanol, ethanol and analogous 2-methylimidazolate derivatives (e.g. ZIF-67) are
or isopropanol as the liquid additives (Figure S23). Interestingly, ongoing.
none of the milling products from the Zn:HMeIm = 1:3
preparations showed evidence of HMeIm in the PXRD pattern,
in line with the hypothesis that extra ligand is encapsulated in
Conclusions
the pores of ZIF-8.
In summary, we have shown for the first time that ZIFs (namely
zni-Zn(Im) and SOD-Zn(MeIm) can be made
mechanochemically from basic zinc carbonate, without any
solvent use at all, and that the reaction progress can be
monitored in situ by measuring the change of pressure inside
the milling vessel due to CO released in the reaction. Such
2
manometric monitoring of the synthesis of the commercially
viable ZIF-8 revealed an unexpected feedback loop, in which the
2
2
)
Solventless synthesis and purification of 90 g of ZIF-8
We have therefore shown that using excess HMeIm in the
mechanochemical reaction of basic zinc carbonate and HMeIm
facilitates the formation of large quantities of pure ZIF-8 at
room temperature under mild conditions. However, the fact
that washing with solvent is still required as part of the
purification process detracts somewhat from the
environmental benefits of using mechanochemistry.
Consequently, a fully solvent-free method for synthesizing and
purifying/activating MOFs would be desirable. To tackle this
problem, we prepared ZIF-8 mechanochemically from basic zinc
carbonate at a 90 g scale and purified it without using solvents,
providing the very first demonstration of a MOF synthesized
without using any solvents at any stage of preparation or
activation. Specifically, the product resulting from a neat
grinding reaction of basic zinc carbonate and HMeIm
2
newly produced ZIF-8 reacts with released CO gas and water to
form a complex zinc carbonate methylimidazolate, the
structure of which has been elucidated here, and provides a
new addition to the already rich landscape of zinc 2-
40
methylimidazolate phases. Formation of the byproduct was
then prevented by addition of excess ligand, enabling large-
scale quantitative synthesis of ZIF-8 from inexpensive and
available precursors, and a so far first example of a totally
solvent-free route for the mechanochemical manufacture and
activation of this MOF.
(Zn:HMeIm = 1:3) carried out in a planetary mill was purified by
sublimation (200 °C under vacuum for 5 hr) of the included Materials and Methods
HMeIm without any detrimental effect on the ZIF-8, as
Details of experimental procedures are given in Electronic
Supporting Information (ESI). Large scale (ca. 15 g)
mechanochemical syntheses were carried out in a Retsch
PM400 mill operating at 300 rpm. Reaction mixtures were
milled in a 250 mL PM GrindControlTM reaction vessel with
seven stainless steel balls (m = 44 g, d = 20 mm, V = 6 mL). Small
scale (200 mg) reactions were done in a 10 mL stainless steel
milling jar with two stainless steel balls (m = 1.3 g, d = 7 mm) at
corroborated by PXRD, TGA and N
2
sorption isotherms (Figures
2
S25-S27). In addition, this route yielded a MOF with 1785 m /g
2
BET surface area of 1758 m /g, comparable to the commercial
form. The sublimed HMeIm was collected as colourless crystals
1
and was found to be pure by solution-state H NMR
spectroscopy, allowing the possibility of reusing the excess
HMeIm.
3
0 Hz. All samples were washed extensively with ethanol to
Scope of the methodology
remove potential unreacted imidazole starting material before
further analysis. The vessel pressure curves, TGA, PXRD, solid-
state NMR and FTIR-ATR data are given in the ESI, along with
details of PXRD structure determination of 1. Crystallographic
data for 1 have been deposited with the Cambridge Structural
Database (CCDC deposition code 1942361).
In principle, the carbonate-based synthesis and reaction
monitoring methodology presented herein should be applicable
to a wide range of MOF materials. Indeed, the use of metal
carbonate reactants was already investigated by Yuan et al.
for zinc-based pillared MOFs and rare earth-based carboxylate
MOFs, while Riccò et al. reported the synthesis of HKUST-1 from
basic copper(II) carbonate. As a preliminary exploration of the
wider applicability of this synthetic methodology, we also
2
7
Conflicts of interest
There are no conflicts to declare.
3
explored the reaction of cobalt(II) carbonate (CoCO ) with HIm
in 1:2 molar ratio, both by neat milling and by LAG with
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1
6 X. Ma, G. K. Lim, K. D. M. Harris, D. C. Apperley,VPie.wNA.rtiHcloe Ortnolinne,
Acknowledgements
M. B. Hursthouse and S. L. James, Cryst. Growth Des., 2012,
DOI: 10.1039/C9SC05514B
This work was funded by NSERC DG (RGPIN-2017-06467),
CREATE and I2I (I2IPJ 485231-2015) grants. KTH and IB
acknowledge support by the NSF (DMR-1610882). IB thanks
Georgetown University (Kunin Fellowship, GSAS Dissertation
Research Grant), and the ICDD (Ludo Frevel Scholarship). FRQNT
Center in Green Chemistry & Catalysis is acknowledged for
support. The École Nationale Supérieure de Chimie de
Clermont-Ferrand is thanked for providing a summer placement
at Cardiff University to F.D. The authors thank MOF
Technologies Ltd. for providing a reference sample of Porolite
12, 5869.
1
1
7 L. Batzdorf, F. Fischer, M. Wilke, K.-J. Wenzel and F.
Emmerling, Angew. Chem. Int. Ed., 2015, 54, 1799.
8 a) C. Bolm and J. G. Hernández, Angew. Chem. Int. Ed., 2019,
5
8, 3285; b) C. Schumacher, D. E. Crawford, B. Raguž, R.
Glaum, S. L. James, C. Bolm and J. G. Hernández, Chem.
Commun., 2018, 54, 8355.
1
9 a) R. Eckert, M. Felderhoff and F. Schüth, Angew. Chem. Int.
Ed., 2017, 56, 2445; b) M. Bilke, P. Losch, O. Vozniuk, A.
Bodach and F. Schüth, J. Am. Chem. Soc., 2019, 141, 11212; c)
H. Schreyer, R. Eckert, S. Immohr, J. de Bellis, M. Felderhoff
and F. Schüth, Angew. Chem. Int. Ed., 2019, 58, 11262.
Z8. W. Y. thanks the National Natural Science Foundation of 20 J. Huot, D. B. Ravnsbæk, J. Zhang, F. Cuevas, M. Latroche and
T. R. Jensen, Prog. Mater. Sci., 2013, 58, 30.
China (21561009) for financial support.
2
1 a) J. E. Oghenevweta, D. Wexler and A. Calka, J. Mater. Sci.,
2
018, 53, 3064; b) G. A. Alanko, D. D. Osterberg, B. J. Jaques,
M. F. Hurley and D. P. Butt, J. Alloys Compd., 2015, 620, 413.
2 A. M. Glushenkov, H. Z. Zhang and Y. Chen, Mater. Lett., 2008,
62, 4047–4049.
Notes and references
2
1
a) S. L. James, C. J. Adams, C. Bolm, D. Braga, P. Collier, T.
Friščić, F. Grepioni, K. D. M. Harris, G. Hyett, W. Jones, A. 23 1 G. Kozma, Á. Kukovecz and Z. Kónya, J. Mol. Struct., 2007,
Krebs, J. Mack, L. Maini, A. G. Orpen, I. P. Parkin, W. C.
834–836, 430–434.
Shearouse, J. W. Steed and D. C. Waddell, Chem. Soc. Rev., 24 Described in: F. Kh. Urakaev and V. V. Boldyrev, Powder Tech.,
2
7
012, 41, 413; b) G.-W. Wang, Chem. Soc. Rev., 2013, 42,
668; c) E. Boldyreva, Chem. Soc. Rev., 2013, 42, 7719; d) N. 25 S. Grätz, D. Beyer, V. Tkachova, S. Hellmann, R. Berger, X. Feng
and L. Borchardt, Chem. Commun., 2018, 54, 5307.
2000. 107, 197.
R. Rightmire and T. P. Hanusa, Dalton Trans., 2016, 45, 2352.
2
3
a) A. Bruckmann, A. Krebs and C. Bolm, Green Chem., 2008, 26 a) M. Baláž, A. Zorkovská, F. Urakaev, P. Baláž, J. Briančin, Z.
1
0, 1131; b) J. L. Howard, Q. Cao and D. L. Browne, Chem. Sci.,
018, 9, 3080.
Bujňáková, M. Achimovičová and E. Gock, RSC Adv., 2016, 6,
87836–87842; b) M. E. Casco, F. Badaczewski, S. Grätz, A.
Tolosa, V. Presser, B. M. Smarsly and L. Borchardt, Carbon,
2018, 139, 325; c) E. Troschke, S. Grätz, T. Lübken and L.
Borchardt, Angew. Chem. Int. Ed., 2017, 56, 6859.
2
a) M. Turberg, K. J. Ardila-Fierro, C. Bolm and J. G. Hernández,
Angew. Chem. Int. Ed., 2018, 57, 10718; b) L. Chen, M. Regan
and J. Mack, ACS Catal., 2016, 6, 868; c) J. G. Hernández and
C. Bolm, J. Org. Chem., 2017, 82, 4007.
27 a) R. Riccò, O. Linder-Patton, K. Sumida, M. J. Styles, K. Liang,
H. Amenitsch, C. J. Doonan and P. Falcaro, Chem. Mater.,
2018, 30, 5630; b) W. Yuan, T. Friščić, D. Apperley and S. L.
James, Angew. Chem. Int. Ed., 2010, 49, 3916; c) W. Yuan, J.
O'Connor and S. L. James CrystEngComm 2010, 12, 3515.
4
5
a) Y. X. Shi, K. Xu, J. K. Clegg, R. Ganguly, H. Hirao, T. Friščić and
F. García, Angew. Chem. Int. Ed., 2016, 55, 12736; b) R. F.
Koby, T. P. Hanusa and N. D. Schley, J. Am. Chem. Soc., 2018,
1
40, 15934.
D. Crawford, J. Casaban, R. Haydon, N. Giri, T. McNally and S. 28 C. J. Adams, M. A . Kurawa, M. Lusi and A. G. Orpen
L. James, Chem. Sci., 2015, 6, 1645.
CrystEngComm 2008, 10, 1790.
6
7
C. Mottillo and T. Friščić, Molecules, 2017, 22, 144.
a) H. Furukawa, K. E. Cordova, M. O'Keeffe and O.Yaghi,
29 T. Friščić, S. L. Childs, S. A. A. Rizvi and W. Jones,
CrystEngComm, 2009, 11, 418.
Science, 2013, 341, 1230444-1; b) A. J. Tansell, C. L. Jones and 30 T. Friščić, D. G. Reid, I. Halasz, R. S. Stein, R. E. Dinnebier and
T. L. Easun, Chem. Cent. J., 2017, 11:100.
M. J. Duer, Angew. Chem. Int. Ed., 2010, 49, 712.
8
9
M. Klimakow, P. Klobes, A. F. Thünemann, K. Rademann and 31 R. Lehnert and F. Z. Z. Seel, Anorg. Allg. Chem., 1980, 464, 187.
F. Emmerling, Chem. Mater., 2010, 22, 5216.
P. A. Julien, K. Užarević, A. D. Katsenis, S. A. J. Kimber, T. Wang,
32 X.-C. Huang, Y.-Y. Lin, J.-P. Zhang and X.-M. Chen, Angew.
Chem. Int. Ed., 2006, 45, 1557.
O. K. Farha, Y. Zhang, J. Casaban, L. S. Germann, M. Etter, R. E. 33 J. T. Hughes, T. D. Bennett, A. K. Cheetham and A. Navrotsky,
Dinnebier, S. L. James, I. Halasz and T. Friščić, J. Am. Chem.
Soc., 2016, 138, 2929.
0 D. Prochowicz, K. Sokołowski, I. Justyniak, A. Kornowicz, D.
J. Am. Chem. Soc., 2013, 135, 598.
34 C. Mottillo and T. Friščić, Angew. Chem. Int. Ed., 2014, 53,
1
7471.
Fairen-Jimenez, T. Friščić and J. Lewinski, Chem. Commun., 35 K. D. M. Harris, Top. Curr. Chem., 2012, 315, 133.
2
015, 51, 4032.
36 J. W. Visser, J. Appl. Crystallogr., 1969, 2, 89.
1
1
1 D. Prochowicz, J. Nawrocki, M. Terlecki, W. Marynowski and J. 37 R. Shirley, The CRYSFIRE System for Automatic Powder
Lewiński, Inorg. Chem., 2018, 57, 13437.
2 a) I. Brekalo, C. M. Kane, A. N. Ley, J. R. Ramirez, T. Friščić and
Indexing: User’s Manual The Lattice Press: Guildford, U.K.,
1999.
K. T. Holman, J. Am. Chem. Soc., 2018, 140, 10104.; b) P. J. 38 A. C. Larson and R. B. Von Dreele, Los Alamos National
Beldon, L. Fábián, R. S. Stein, A. Thirumurugan, A. K. Cheetham
and T. Friščić, Angew. Chem. Int. Ed., 2010, 49, 9640.
3 A. M. Fidelli, B. Karadeniz, A. J. Howarth, I. Huskić, L. S.
Germann, I. Halasz, M. Etter, S.-Y. Moon, R. E. Dinnebier, V.
Stilinović, O. K. Farha, T. Friščić and K. Užarević, Chem.
Commun., 2018, 54, 6999.
Laboratory Report, 2004, LAUR 86-748.
39 a) B. M. Kariuki, P. Calcagno, K. D. M. Harris, D. Philp and R. L.
Johnston, Angew. Chem. Int. Ed., 1999, 38, 831; b) E. Y.
Cheung, E. E. McCabe, K. D. M. Harris, R. L. Johnston, E.
Tedesco, K. M. P. Raja and P. Balaram, Angew. Chem. Int. Ed.,
2002, 41, 494; c) D. Albesa-Jové, B. M. Kariuki, S. J. Kitchin, L.
Grice, E. Y. Cheung and K. D. M. Harris, ChemPhysChem, 2004,
5, 414; d) K. Fujii, M. T. Young and K. D. M. Harris, J. Struct.
Biol., 2011, 174, 461; e) P. A. Williams, C. E. Hughes and K. D.
M. Harris, Angew. Chem. Int. Ed., 2015, 54, 3973; f) C. E.
1
1
1
4 P. A. Julien, C. Mottillo and T. Friščić, Green Chem., 2017, 19,
2
729.
5 X. Ma, W. Yuan, S. E. J. Bell and S. L. James, Chem. Commun.,
014, 50, 1585.
2
6
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DOI: 10.1039/C9SC05514B
4
0 a) Q. Shi, Z. Chen, Z. Song, J. Li and J. Dong, Angew. Chem. Int.
Ed., 2010, 50, 672; b) A. D. Katsenis, A. Puškarić, V. Štrukil, C.
Mottillo, P. A. Julien, K. Užarević, M.-H. Pham, T.-O. Do, S. A.
J. Kimber, P. Lazić, O. Magdysyuk, R. E. Dinnebier, I. Halasz and
T. Friščić, Nat. Commun., 2015, 6:6662; c) L.-R. Chen, J. Yao, Q.
Gu, S. Smeets, C. Baerlocher, H. Gu, D. Zhu, W. Morris, O. M.
Yaghi and H. Wang, Chem. Commun., 2013, 49, 9500.
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