Diffusion Control in Single-Site Zinc Reticular Amination Catalysts

Article abstract of DOI:10.1021/acs.inorgchem.0c02624

Zn-containing metal-organic frameworks have been used for the first time as heterogeneous catalysts in the amination of C-Cl bonds. The use of extended bis(pyrazolate) linkers can generate highly porous architectures, which favor the diffusion of amines t

Full text of DOI:10.1021/acs.inorgchem.0c02624

pubs.acs.org/IC
Article
Diffusion Control in Single-Site Zinc Reticular Amination Catalysts
́
Francisco G. Cirujano,* Elena Lopez-Maya, Neyvis Almora-Barrios, Ana Rubio-Gaspar, Nuria Martín,
Jorge A. R. Navarro, and Carlos Martí-Gastaldo*
Cite This: https://dx.doi.org/10.1021/acs.inorgchem.0c02624
Read Online
sı
*
Metrics & More
Article Recommendations
Supporting Information
ACCESS
ABSTRACT: Zn-containing metal−organic frameworks have been used for the first time
as heterogeneous catalysts in the amination of C−Cl bonds. The use of extended
bis(pyrazolate) linkers can generate highly porous architectures, which favor the diffusion
of amines to the confined spaces with respect to other imidazolate frameworks with
narrower pore windows. The N4Zn nodes of the Zn-reticular framework show comparable
activity to state-of-the-art homogeneous Zn amination catalysts, avoiding the use of basic
conditions, precious metals, or other additives. This is combined with long-term activity
and stability upon several reaction cycles, without contamination of the reaction product.
cross-couplings,31,32 and carboxylations.33 Pyrazolate groups
favor soft−soft acid−base interactions (with divalent metals)
for higher thermal stability and exceptional chemical stability in
acid and basic conditions, compared to carboxylate MOFs.22
Moreover, only one Zn single site is present at the N4Zn SBUs
of the azolate-type Zn-MOFs (see Figure 1), with respect to
the four Zn present as Zn4O(CO2)3 in carboxylate-type Zn-
MOFs (e.g., MOF-5, MOF-74). However, the use of parent
MBDP frameworks (BDP = 1,4-bis(pyrazol-4-yl)benzene) as
catalysts has been largely overlooked.34,35 Previous works rely
on the encapsulation of metals (Cu, Pd, Ag) in the pores of the
INTRODUCTION
■
C−N couplings involving the addition of N−H groups to C−
Cl bonds in N-heterocycles are important reaction steps during
the assembly of high value-added molecules. In the
pharmaceutical industry, efficient methods for the production
of substituted pyridines by C−Cl amination are urgently
needed.1,2 Contemporary synthetic methods as Buchwald−
Hartwig or Ullmann-type C−N couplings often require costly,
air-sensitive homogeneous catalysts and stoichiometric
amounts of base.3 In this sense, the use of a zinc(II) Lewis
acid (which is cheaper, less toxic, and naturally more abundant
than precious metal catalysts) has been reported to activate 4-
chloropyridine during nucleophilic aromatic substitutions with
amines.4,5 However, these promising results also anticipate the
limitations intrinsic to homogeneous catalysis, as the recovery
and recycle of the catalyst or the eventual contamination of the
product. In order to improve the sustainability and innovate
the catalysis of organic transformations, different approaches
such as the use of ionic liquids, nanocages, coordination
networks, or metal−organic frameworks (MOFs) are bridging
the gap between traditional homogeneous and heterogeneous
catalysts.6−14 The incorporation of Zn(II) as a single site (well-
positioned and separated) in open frameworks as zeolites,
coordination polymers, or MOFs would permit translating this
reactivity to the heterogeneous phase for simple separation of
the product, thus avoiding its contamination.15−21
Pioneering studies of copper active sites in MOFs for N-
arylations of aryl bromides with aromatic amines and N-
heterocycles using Ullmann-type couplings have been
reported.22,23 However, the harsh conditions used, which
include large amounts of base, compromises the stability and
recyclability of the framework. This limitation might be more
easily overcome by using earth abundant metal-azolate
frameworks based on extended linkers.24−28 This family of
robust MOFs have demonstrated catalytic activity in aldol
condensations−Michael-type additions,29 hydroaminations,30
Figure 1. Structure of the N4Zn nodes in ZnBDP (a) and ZIF-8 (b).
The green spheres represent the pore diameter of similar size in both
cases. Dimensions of the pore aperture are indicated and highlighted
with a red sphere in the case of ZIF-8 to account for disfavored
substrate diffusion.
Received: September 2, 2020
https://dx.doi.org/10.1021/acs.inorgchem.0c02624
© XXXX American Chemical Society
Inorg. Chem. XXXX, XXX, XXX−XXX
A

Inorganic Chemistry
pubs.acs.org/IC
Article
framework, which are responsible for the catalytic activity,
while the framework is exclusively used as innocent porous
support to prevent the aggregation and deactivation of active
sites.
centrifugation and employed in subsequent reaction cycles
without apparent loss in activity: kZnBDP = 9.3 × 10−3, 8.8 ×
10−3, 8.2 × 10−3, and 7.8 × 10−3 h−1 for the four subsequent
cycles (see Figure S6 in the Supporting Information).
Therefore, the cumulative rate constant per Zn active site
after three cycles is 3.8 times higher when using the ZnBDP
MOF (0.15 h−1) with respect to the homogeneous Zn(NO3)2
catalyst (0.04 h−1). The high stability of both MOFs is proven
due to the maintenance of XRD patterns after 72 h of reaction,
with only minor changes attributed to changes in pore
occupancy (see Figure 3).38 A hot filtration test of ZnBDP
Here we study for the first time the activity of unmodified
ZnBDP as a heterogeneous catalyst, based on the reported
Zn(NO3)2 homogeneous C−Cl amination catalyst.4 This
framework consists of tetrahedrally coordinated N4Zn metal
centers interconnected by BDP linkers to generate 3D square
channels with edges of 13.2 Å, large pores of close to 11.1 Å
(see Figure 1a).36−38 In order to account for the changes of
porosity over substrate diffusion and performance, the zinc-
pyrazolate ZnBDP was compared with that of zinc-imidazolate
ZIF-8. This choice is based on the similar environment of the
ZnN4 units, but featuring a different porous architecture with
large 11.6 Å pores connected through small apertures of 3.4 Å
(see Figure 1b).39
RESULTS AND DISCUSSION
■
We tested both Zn reticular catalysts in the proof-of-concept
amination of the sp2 C4 carbon of 4-chloropyridine (Cl-py)
with morpholine. The yield of the 4-aminated pyridine product
after 72 h of reaction increases in the order ZIF-8 (26%) <
ZnBDP (51%) < Zn(NO3)2 (82%), for the same catalyst mass
(see Figure 2a). The kinetic rate constants were obtained from
Figure 3. Powder XRD patters of ZnBDP (a) with respect to ZIF-8
(b) catalysts before and after the amination of Cl-py with morpholine.
demonstrated the heterogeneous nature of the reaction (see
Figure S6 in the Supporting Information). ICP analysis of the
filtrate results in 0.21 wt % Zn leaching from ZnBDP. Taking
into account that 13 wt % of Zn in the MOF structure is used
with respect to 4-chloropyridine, only 0.03 wt % Zn will be in
the form of leached homogeneous Zn2+. This amount is way
below the 1.4 wt % Zn used in the reported homogeneous
catalyzed process,4 confirming the results of the hot filtration
tests. Furthermore, no evidence of 4-pyridination of 1,4-
bis(pyrazol-4-yl)benzene ligand was found according to the
NMR spectra of the digested MOF before and after the
reaction (see Figure S7). Therefore, the changes in catalytic
performance between single-site Zn(II) frameworks cannot be
ascribed to the potential degradation of ZnBDP but to
differences imposed by the dimensions of their pores and
channels.
Figure 2. Kinetic profiles (a) and activity (TONZn) expressed in mol
of Cl-py converted divided per mol of Zn (b), for the amination of 10
mg of Cl-py catalyzed by 10 mg of ZnBDP (red) or ZIF-8 (blue) with
respect to Zn(NO3)2 (black).
To further confirm the key role played by the diffusion of
the substrates into the ZnN4-MOF active sites, solid−liquid
adsorption experiments of a solution of 4-chloropyridine (Cl-
py) in CH3CN (2.5 mg·mL−1) were performed. The ZnBDP
the linear fit of the logarithm of the 4-chloropyridine
conversion vs time, assuming a pseudo-first-order reaction,
which resulted in different slopes (see Figure S5 in the
Supporting Information). The kinetic rate constant increases as
kZIF‑8 (0.004 h−1) < kZnBDP (0.009 h−1) < kZnNO3 (0.024 h−1).
For the same Zn-catalyst mass, the Cl-py/Zn molar ratio
increases in the order Zn(NO3)2 < ZIF-8 < ZnBDP (being 1.8
< 2.3 < 4.5, respectively). When the kinetic rate constants are
multiplied by the corresponding substrate/catalyst ratio, a
normalized rate constant per Zn active site is obtained. Its
value is similar for the heterogeneous ZnBDP and the
homogeneous Zn(NO3)2 (ca. 0.04 h−1) and four times higher
than in the case of microporous ZIF-8 (ca. 0.01 h−1).
The number of product molecules per zinc site (TONZn)
during the course of the reaction is represented in Figure 2b. It
indicates the good catalytic performance of ZnBDP with
respect to ZIF-8 and the Zn(NO3)2 homogeneous catalyst.4 In
contrast to the soluble Zn2+ species, which are not possible to
recover and recycle, ZnBDP can be isolated by simple
shows a higher uptake with respect to ZIF-8, resulting in 1.0 vs
−1
0.3 molCl‑py·molZn
(see Table S4 in the Supporting
Information). A computational study has been performed
with both reticular Zn catalysts (i.e., Zn12(C4N2H5)24 and
Zn4(C12N4H8)4 modeled crystalline cells of ZIF-8 and ZnBDP,
respectively) in order to understand the experimental results.
The calculated values are in line with the experimental uptake
of Cl-py molecules by the MOFs, corresponding to 0.4 and 1.0
−1
molCl‑py or morpholine·molZn docked in ZIF-8 and ZnBDP,
respectively. More importantly, the molecular dynamics results
indicate a higher diffusivity in the ZnBDP with respect to ZIF-
8, especially in the case of the amine nucleophile (2 × 10−5 vs
1 × 10−7 cm2·s−1), as shown in Figure 4 (molecule A). The
adsorption and diffusion results further confirm that the
changes in the pore window of ZnBDP and ZIF-8 may be the
origin of their different catalytic performance. On the one
hand, the 1.3 nm edges of the square channels from ZnBDP
favor the infiltration and docking of Cl-py molecules inside the
B
https://dx.doi.org/10.1021/acs.inorgchem.0c02624
Inorg. Chem. XXXX, XXX, XXX−XXX

Inorganic Chemistry
pubs.acs.org/IC
Article
ZIF-8 in the case of bulkier substrates such as N-phenylaniline
(ca. 1.3 nm size). Indeed, molecular mechanics simulations
confirm the docking of 6 and 3 molecules of N-methylaniline,
or 3 and 1 molecules of N-phenylaniline for ZnBDP and ZIF-8,
respectively (see Figures S10−S13 in the Supporting
Information). As previously described for morpholine, the
diffusivity of both reaction substrates is higher on ZnBDP than
in ZIF-8 (see Table S5). The changes are more pronounced
when passing from amine B to amine C, where only steric
effects are introduced by changing one of the N-substituents.
The DZnBDP/DZIF‑8 diffusivity ratio in the case of amine B is
522, with respect to the value of 376 for amine C. In both
cases, the diffusivity of the amine in the large pores of ZnBDP
is up to 3 orders of magnitude higher with respect to the
traditional ZIF-8 Zn reticular catalyst.
Figure 4. TON of Zn sites (bars, left axis) in the amination of Cl-py
with morpholine (A), N-methylaniline (B), and N-phenylaniline (C),
together with the diffusivity (Damine) of A, B, or C (circles and
triangles, logarithmic right axis) in ZnBDP (red) or ZIF-8 (blue).
Furthermore, density functional theory (DFT, see Support-
ing Information for details) allows us to propose a reaction
mechanism based on Zn single sites instead of dual metal sites
reported with other MOF catalysts.41 As shown in Figure 5, the
pore cavities for subsequent reaction with morpholine. On the
other hand, the restricted diffusion of reactants across the 0.3
nm pore windows of ZIF-8 precludes the inner Zn−N active
sites to activate the reactants for the amination reaction (see
Figure 1).
To rule out the contribution of the Zn active sites located at
the external surface of the crystals, the catalytic activity of a
second ZIF-8 sample with a higher external surface area was
tested (see ZIF-8H O in Figure S1 and Table S1).40 The yield
2
obtained after 48 h of reaction between Cl-py and amine A is
similar with both samples (∼20%), confirming the dominant
role of the microporous area and how catalytic activity seems
to be restricted to the accessibility of the substrates to the
pores of the bulk crystal. Therefore, it seems plausible that
when using ZnBDP, the rapid diffusion and confinement of the
amination substrates inside the large MOF pores favor the
course of the reaction, without the diffusion limitations toward
the inner active sites occurring in ZIF-8.
Other aryl halides and NH derivatives were employed as
substrates of the ZnBDP reticular catalysts. For instance, the
reaction of morpholine with 4-chloroquinoline results in a
slightly higher yield of the pharmaceutically relevant 4-
aminoquinoline,2 with respect to 4-chloropyridine (25% vs
15% respectively) after 24 h of reaction (see Figure S9). The
higher reactivity of the quinoline derivative (having one extra
benzene ring) with respect to the pyridine one may be the
result of better solubility in the reaction media and more
favorable interactions with the aromatic linker of the ZnBDP.
Two additional N-substituted anilines with different sub-
stituent sizes, i.e. N-methylaniline (B in Figure 4) and N-
phenylaniline (C in Figure 4), were employed in the amination
of Cl-py, in order to check the effect of the substituent size
(methyl vs phenyl) on the catalytic performance of both Zn-
reticular catalysts. The yields of the two new 4-aminopyridines
obtained after 72 h with ZnBDP as catalyst were 98% and 50%
for amine B and C, respectively. However, these yields
decreased to 51% and 17% (for B and C, respectively) when
using ZIF-8 as catalyst (see Table S3).
Figure 5. Proposed mechanism for the amination of Cl-py with
morpholine catalyzed by acid−base sites in ZnBDP. (a) Interaction of
morpholine molecules with the Zn and H-transfer from the
morpholine to the N-linker, (b) 4-chloropyridine adsorption on Zn
sites. (c) C−N bond formation between 4-chloropyridine and
morpholine and (d) active site regeneration.
interaction of morpholine molecules with the Zn atom takes
place through a concerted step (Figure 5a), where the proton
of the morpholine is transferred to the ligand leaving a free site
in the Zn atoms for its adsorption. Although the adsorption
strength of the morpholine is weak (+2.9 kJ mol−1), the
protonation process of the BDP pyrazolate linker coordinated
to the Zn site (transient BDP decoordination of 1 out of the 4
N−Zn bonds) leaves the possibility that Cl-py interacts
strongly with the Zn atom by −135.1 kJ mol−1 (Figure 5b).
This agrees well with the FT-IR spectrum of ZnBDP after 24 h
of reaction between Cl-py and morpholine, which shows a
band around 1635 cm−1 (different from that of the free 4-
chloropyridine at 1490 cm−1),42 suggesting that the N4Zn
SBUs can act as a Lewis acid. These sites are available for
interaction with the nitrogen lone pair of 4-chloropyridine (see
Figure S8), as recently described for homogeneous Zn(II)
complexes.43 The (reversible) complex formation between the
Zn(II) Lewis acid and pyridine Lewis base through the binding
The higher TONZnBDP/TONZIF‑8 ratio when using amine C
as the amination agent with respect to amine B (TONZnBDP
/
TONZIF‑8 = 5.8 vs 3.8) suggests the steric hindrance of the
phenyl substituted amine when diffusing into the MOF pores.
Thus, despite the similar difference in activity between ZnBDP
and ZIF-8 in the case of small N-methylaniline (ca. 0.9 nm
size), the performance of ZnBDP is boosted with respect to
C
https://dx.doi.org/10.1021/acs.inorgchem.0c02624
Inorg. Chem. XXXX, XXX, XXX−XXX

Inorganic Chemistry
pubs.acs.org/IC
Article
of Zn to the pyridine nitrogen has been also proposed for the
homogeneous case.4,5 Finally, the formation of the product
after the SNAr reaction is exothermic by −212.3 kJ mol−1
(Figure 5c).
Carlos Martí-Gastaldo − Instituto de Ciencia Molecular
(ICMol), Universitat de València, 46980 Paterna, Valencia,
Spain; orcid.org/0000-0003-3203-0047;
Email: carlos.marti@uv.es
Our simulations suggest that differences in activity are
associated with the acid−base properties of the reagents with
respect to the linker. This is supported by the fact that the pKa
of the −NH− in the pyrazolate is much higher than that of
morpholine (19.8 vs 8.4, respectively). In addition, we have
studied an alternative model in which both the morpholine and
Cl-py interact with two vicinal Zn atoms (presumably at
eventual missing-linker defect sites; see Figure S2 and Table
S2). This model is exothermic by −35.7 kJ mol−1 but
significantly less favorable than the single-site model (−131.1
kJ mol−1; see Supporting Information for details). Moreover,
the distance between the C of the Cl-py and the N of the
morpholine is 4.43 Å, which hinders the SNAr reaction (see
Figure S14) in the dual-site mechanism, with respect to the
single-site proposed here. Further studies for the validation of
the proposed mechanism are ongoing.
Authors
́
Elena Lopez-Maya − Instituto de Ciencia Molecular (ICMol),
Universitat de València, 46980 Paterna, Valencia, Spain
Neyvis Almora-Barrios − Instituto de Ciencia Molecular
(ICMol), Universitat de València, 46980 Paterna, Valencia,
Spain; orcid.org/0000-0001-5269-2705
Ana Rubio-Gaspar − Instituto de Ciencia Molecular (ICMol),
Universitat de València, 46980 Paterna, Valencia, Spain
Nuria Martín − Instituto de Ciencia Molecular (ICMol),
Universitat de València, 46980 Paterna, Valencia, Spain
Jorge A. R. Navarro − Department of Inorganic Chemistry,
University of Granada, 18071 Granada, Spain
Complete contact information is available at:
https://pubs.acs.org/10.1021/acs.inorgchem.0c02624
Notes
CONCLUSIONS
The authors declare no competing financial interest.
■
In conclusion, Zn-catalyzed amination of 4-chloropyridine is
reported here using a heterogeneous catalyst for the first time.
The porous architecture of the ZnBDP MOF provides higher
uptake capacity and more favorable mass transfer (up to 3
orders of magnitude higher) compared to microporous ZIF-8.
The larger Zn-bis(pyrazolate) cavities favor the transport of
the substrate molecules inside the ZnBDP pores, where they
access the inner active sites, as shown by the calculated
diffusivities of the substrates in both MOFs. In contrast, the Zn
sites are less accessible to the reagents in the case of ZIF-8,
resulting in a decrease of catalytic activity below half of the
value of ZnBDP. TON values of the Zn active sites which are
up to 6 times higher are obtained in the transformation of
bulky substrates (i.e., N-phenylaniline), when those catalytic
sites are in a more open Zn-azolate structure. These
observations confirm the positive effects of the activation of
the 4-chloropyridine and different amine substrates inside the
porous spaces of ZnBDP, where the inner Zn active sites are
more accessible than in the far more popular zeolitic
imidazolate frameworks. The use of the heterogeneous Zn-
bis(pyrazolate) catalyst is a sustainable alternative to the use of
homogeneous Zn salts, which can be outperformed in terms of
activity and stability, paving the way for the synthesis of
pharmaceutically interesting intermediates in an environ-
mentally benign manner.
ACKNOWLEDGMENTS
■
The project that gave rise to these results received the support
of a fellowship from the “la Caixa” Foundation (ID
100010434). The fellowship code is LCF/BQ/PI19/
11690011. E.L.-M. thanks the Spanish government for a Juan
de la Cierva Fellowship (FJCI-2017-32956). A.R.G. acknowl-
edges funding from Generalitat Valencia and Fondo Social
Europeo. N.M. acknowledges the “Juan de la Cierva
́
formacion” fellowship with code FJC2018-035455-I. J.A.R.N.
is thankful for CTQ2017-84692-R and EU FEDER funding.
We also thank the EU (ERC Stg Chem-fs-MOF 714122) and
Spanish government (CTQ2017-83486-P and CEX2019-
000919-M). UV-Tirant and UV-LluisVives are acknowledged
for the computational resources.
REFERENCES
■
(1) Fussell, S. J.; Luan, A.; Peach, P.; Scotney, G. A three-step
synthesis of 4-(4-iodo-1H-pyrazol-1-yl)piperidine, a key intermediate
in the synthesis of Crizotinib. Tetrahedron Lett. 2012, 53, 948−951.
(2) Natarajan, J. K.; Alumasa, J.; Yearick, K.; Ekoue-Kovi, K. A.;
Casabianca, L. B.; de Dios, A. C.; Roepe, P. D.; Wolf, C. Overcoming
Drug Resistance to Heme-Targeted Antimalarials by Systematic Side
Chain Variation of 7-Chloro-4-aminoquinolines. J. Med. Chem. 2008,
51, 3466−3479.
(3) Surry, D. S.; Buchwald, S. L. Biaryl phosphane ligands in
palladium-catalyzed amination. Angew. Chem., Int. Ed. 2008, 47,
6338−6361.
ASSOCIATED CONTENT
■
(4) Abou-Shehada, S.; Teasdale, M. C.; Bull, S. D.; Wade, C. E.;
Williams, J. M. J. Lewis acid activation of pyridines for nucleophilic
aromatic substitution and conjugate addition. ChemSusChem 2015, 8,
1083−1087.
(5) Kinens, A.; Balkaitis, S.; Suna, E. Preparative-Scale Synthesis of
Vedejs Chiral DMAP Catalysts. J. Org. Chem. 2018, 83, 12449−
12459.
sı
* Supporting Information
The Supporting Information is available free of charge at
https://pubs.acs.org/doi/10.1021/acs.inorgchem.0c02624.
Synthesis and characterization of the Zn-MOF catalysts,
catalytic and computational details (PDF)
(6) Cirujano, F. G.; Stalpaert, M.; De Vos, D. E. Ionic liquids vs.
microporous solids as reusable reaction media for the catalytic C−H
functionalization of indoles with alcohols. Green Chem. 2018, 20,
2481−2485.
(7) Sheng, K.; Fan, L. M.; Tian, X. F.; Gupta, R. K.; Gao, L.; Tung,
C. H.; Sun, D. Temperature-induced Sn(II) supramolecular isomeric
frameworks as promising heterogeneous catalysts for cyanosilylation
of aldehydes. Sci. China: Chem. 2020, 63, 182−186.
AUTHOR INFORMATION
■
Corresponding Authors
Francisco G. Cirujano − Instituto de Ciencia Molecular
(ICMol), Universitat de València, 46980 Paterna, Valencia,
Spain; orcid.org/0000-0002-0159-5777;
Email: francisco.c.garcia@uv.es
D
https://dx.doi.org/10.1021/acs.inorgchem.0c02624
Inorg. Chem. XXXX, XXX, XXX−XXX

Inorganic Chemistry
pubs.acs.org/IC
Article
̌
́
(8) Liu, Y. N.; Su, H. F.; Li, Y. W.; Liu, Q. Y.; Jaglicic, Z.; Wang, W.
G.; Tung, C. H.; Sun, D. Space Craft-like Octanuclear Co(II)-
Silsesquioxane Nanocages: Synthesis, Structure, Magnetic Properties,
Solution Behavior, and Catalytic Activity for Hydroboration of
Ketones. Inorg. Chem. 2019, 58, 4574−4582.
Kaskel, S.; Barea, E.; Navarro, J. A. R. Highly Hydrophobic
Isoreticular Porous Metal−Organic Frameworks for the Capture of
Harmful Volatile Organic Compounds. Angew. Chem., Int. Ed. 2013,
52, 8290−8294.
̌
(27) Taylor, M.; Runcevski, T.; Oktawiec, J.; Gonzalez, M.;
(9) Zhao, M.; Huang, S.; Fu, Q.; Li, W.; Guo, R.; Yao, Q.; Wang, F.;
Cui, P.; Tung, C. H.; Sun, D. Ambient Chemical Fixation of CO2
Using a Robust Ag27 Cluster-Based Two-Dimensional Metal−Organic
Framework. Angew. Chem., Int. Ed. 2020, 59, 20031−20036.
(10) Xu, Z.; Han, L. L.; Zhuang, G. L.; Bai, J.; Sun, D. In Situ
Construction of Three Anion-Dependent Cu(I) Coordination
Networks as Promising Heterogeneous Catalysts for Azide−Alkyne
“Click” Reactions. Inorg. Chem. 2015, 54, 4737−4743.
Siegelman, R.; Mason, J.; Ye, J.; Brown, C.; Long, J. Tuning the
Adsorption-Induced Phase Change in the Flexible Metal−Organic
Framework Co(bdp). J. Am. Chem. Soc. 2016, 138, 15019−15026.
(28) Lv, X.; Wang, K.; Wang, B.; Su, J.; Zou, X.; Xie, Y.; Li, J.; Zhou,
H. A Base-Resistant Metalloporphyrin Metal−Organic Framework for
C−H Bond Halogenation. J. Am. Chem. Soc. 2017, 139, 211−217.
(29) Cirujano, F. G.; Lopez-Maya, E.; Rodriguez-Albelo, M.; Barea,
E.; Navarro, J. A. R.; De Vos, D. E. Selective one-pot two-step C-C
bond formation using MOFs with mild basicity as heterogeneous
catalysts. ChemCatChem 2017, 9, 4019−4023.
(30) Cirujano, F. G.; Lopez-Maya, E.; Navarro, J. A. R.; De Vos, D.
E. Pd (II)−Ni (II) pyrazolate framework as active and recyclable
catalyst for the hydroamination of terminal alkynes. Top. Catal. 2018,
61, 1414−1423.
(31) Augustyniak, A. W.; Sadakiyo, M.; Navarro, J. A. R.; Trzeciak,
A. M. Palladium nanoparticles supported on a nickel pyrazolate metal
organic framework as a catalyst for Suzuki and carbonylative Suzuki
couplings. Dalton Trans. 2016, 45, 13525−13531.
(32) Tarnowicz-Ligus, S.; Augustyniak, A.; Trzeciak, A. M.
Incorporation of PdCl2P2 Complexes in Ni-MOF for Catalyzing
Heck Arylation of Functionalized Olefins. Eur. J. Inorg. Chem. 2019,
2019, 4282−4288.
(33) Yang, H.; Zhang, X.; Zhang, G.; Fei, H. An alkaline-resistant
Ag(i)-anchored pyrazolate-based metal−organic framework for
chemical fixation of CO2. Chem. Commun. 2018, 54, 4469−4472.
(34) Timokhin, I.; Pettinari, C.; Marchetti, F.; Pettinari, R.;
Condello, F.; Galli, S.; Alegria, E. C. B. A.; Martins, L. M. D. R. S.;
Pombeiro, A. J. L. Novel Coordination Polymers with (Pyrazolato)-
Based Tectons: Catalytic Activity in the Peroxidative Oxidation of
Alcohols and Cyclohexane. Cryst. Growth Des. 2015, 15, 2303−2317.
(35) Lucarelli, C.; Galli, S.; Maspero, A.; Cimino, A.; Bandinelli, C.;
Lolli, A.; Ochoa, J. V.; Vaccari, A.; Cavani, F.; Albonetti, S.
Adsorbent−Adsorbate Interactions in the Oxidation of HMF
Catalyzed by Ni-Based MOFs: A DRIFT and FT-IR Insight. J.
Phys. Chem. C 2016, 120 (28), 15310−15321.
(36) Galli, S.; Masciocchi, N.; Colombo, V.; Maspero, A.; Palmisano,
G.; Lopez-Garzon, F. J.; Domingo-García, M.; Fernandez-Morales, I.;
Barea, E.; Navarro, J. A. R. Adsorption of Harmful Organic Vapors by
Flexible Hydrophobic Bis-pyrazolate Based MOFs. Chem. Mater.
2010, 22, 1664−1672.
(37) Colombo, V.; Montoro, C.; Maspero, A.; Palmisano, G.;
Masciocchi, N.; Galli, S.; Barea, E.; Navarro, J. A. R. Tuning the
Adsorption Properties of Isoreticular Pyrazolate-Based Metal−
Organic Frameworks through Ligand Modification. J. Am. Chem.
Soc. 2012, 134, 12830−12843.
(11) Cao, C. S.; Xia, S. M.; Song, Z. J.; Xu, H.; Shi, Y.; He, L. N.;
Cheng, P.; Zhao, B. Highly Efficient Conversion of Propargylic
Amines and CO2 Catalyzed by Noble-Metal-Free [Zn116]
Nanocages. Angew. Chem., Int. Ed. 2020, 59, 8586−8593.
(12) Hou, S. L.; Dong, J.; Jiang, X. L.; Jiao, Z. H.; Zhao, B. A Noble-
Metal-Free Metal−Organic Framework (MOF) Catalyst for the
Highly Efficient Conversion of CO2 with Propargylic Alcohols.
Angew. Chem., Int. Ed. 2019, 58, 577−581.
(13) Cirujano, F. G. Engineered MOFs and Enzymes for the
Synthesis of Active Pharmaceutical Ingredients. ChemCatChem 2019,
11, 5671−5685.
(14) Martin, N.; Cirujano, F. G. Organic synthesis of high added
value molecules with MOF catalysts. Org. Biomol. Chem. 2020, 18,
8058−8073.
(15) Penzien, J.; Mu
̈
ller, T. E.; Lercher, J. A. Zinc-ion exchanged
zeolites for the intramolecular hydroamination of 6-aminohex-1-yne.
Chem. Commun. 2000, 1753−1754.
(16) Martin, N.; Dusselier, M.; De Vos, D. E.; Cirujano, F. G. Metal-
Organic Framework Derived Metal Oxide Clusters in Porous
Aluminosilicates: A Catalyst Design for the Synthesis of Bioactive
aza-Heterocycles. ACS Catal. 2019, 9, 44−48.
(17) Marquez, C.; Cirujano, F. G.; Van Goethem, C.; Vankelecom,
I.; De Vos, D.; De Baerdemaeker, T. Tunable Prussian blue analogues
for the selective synthesis of propargylamines through A3 coupling.
Catal. Sci. Technol. 2018, 8, 2061−2065.
(18) Marquez, C.; Rivera-Torrente, M.; Paalanen, P. P.;
Weckhuysen, B. M.; Cirujano, F. G.; De Vos, D.; De Baerdemaeker,
T. Increasing the availability of active sites in Zn-Co double metal
cyanides by dispersion onto a SiO2 support. J. Catal. 2017, 354, 92−
99.
(19) Tran, U. P. N.; Le, K. K. A.; Phan, N. T. S. Expanding
Applications of Metal−Organic Frameworks: Zeolite Imidazolate
Framework ZIF-8 as an Efficient Heterogeneous Catalyst for the
Knoevenagel Reaction. ACS Catal. 2011, 1 (2), 120−127.
(20) Roy, S.; George, C. B.; Ratner, M. A. Catalysis by a Zinc-
Porphyrin-Based Metal−Organic Framework: From Theory to
Computational Design. J. Phys. Chem. C 2012, 116, 23494−23502.
(21) Phan, N. T.S.; Le, K. K.A.; Phan, T. D. MOF-5 as an efficient
heterogeneous catalyst for Friedel−Crafts alkylation reactions. Appl.
Catal., A 2010, 382, 246−253.
(22) Maity, T.; Saha, D.; Koner, S. Aromatic N-Arylations Catalyzed
by Copper-Anchored Porous Zinc-Based Metal−Organic Framework
under Heterogeneous Conditions. ChemCatChem 2014, 6, 2373−
2383.
(23) Truong, T.; Nguyen, C. V.; Truong, N. T.; Phan, N. T. S.
Ligand-free N-arylation of heterocycles using metal−organic frame-
work [Cu(INA)2] as an efficient heterogeneous catalyst. RSC Adv.
2015, 5, 107547−107556.
(38) Rojas, S.; Carmona, F. J.; Maldonado, C. R.; Horcajada, P.;
Hidalgo, T.; Serre, C.; Navarro, J. A. R.; Barea, E. Nanoscaled Zinc
Pyrazolate Metal−Organic Frameworks as Drug-Delivery Systems.
Inorg. Chem. 2016, 55, 2650−2663.
̂
́
(39) Park, K. S.; Ni, Z.; Cote, A. P.; Choi, J. Y.; Huang, R.; Uribe-
Romo, F. J.; Chae, H. K.; O’Keeffe, M.; Yaghi, O. M. Exceptional
chemical and thermal stability of zeolitic imidazolate frameworks.
Proc. Natl. Acad. Sci. U. S. A. 2006, 103, 10186−10191.
(40) He, M.; Yao, J.; Liu, Q.; Wang, K.; Chen, F.; Wang, H. Facile
synthesis of zeolitic imidazolate framework-8 from a concentrated
aqueous solution. Microporous Mesoporous Mater. 2014, 184, 55−60.
(41) Castells-Gil, J.; Padial, N. M.; Almora-Barrios, N.; Gil-San-
(24) Navarro, J. A. R. Impact of Defects on Pyrazolate Based Metal
Organic Frameworks. Isr. J. Chem. 2018, 58, 1112−1118.
(25) Desai, A. V.; Sharma, S.; Let, S.; Ghosh, S. K. N-donor linker
based metal-organic frameworks (MOFs): Advancement and
prospects as functional materials. Coord. Chem. Rev. 2019, 395,
146−192.
́
́
Millan, R.; Romero-Angel, M.; Torres, V.; da Silva, I.; Vieira, B. C. J.;
Waerenborgh, J. C.; Jagiello, J.; Navarro, J. A. R.; Tatay, S.; Martí-
Gastaldo, C. Heterometallic Titanium-Organic Frameworks as Dual-
Metal Catalysts for Synergistic Non-buffered Hydrolysis of Nerve
Agent Simulants. Chem. 2020, 6, 3118.
́
́
(26) Padial, N.; Procopio, E.; Montoro, C.; Lopez-Maya, E.; Oltra,
(42) Busto, E.; Gotor-Fernandez, V.; Gotor, V. Enantioselective
J.; Colombo, V.; Maspero, A.; Masciocchi, N.; Galli, S.; Senkovska, I.;
Synthesis of 4-(Dimethylamino)pyridines through a Chemical
E
https://dx.doi.org/10.1021/acs.inorgchem.0c02624
Inorg. Chem. XXXX, XXX, XXX−XXX

Inorganic Chemistry
pubs.acs.org/IC
Article
Oxidation-Enzymatic Reduction Sequence. Application in Asymmet-
ric Catalysis. Adv. Synth. Catal. 2006, 348, 2626−2632.
(43) Saygili, Y.; Kim, H. S.; Yang, B.; Suo, J.; Munoz-Garcia, A. B.;
̃
Pavone, M.; Hagfeldt, A. Revealing the Mechanism of Doping of
spiroMeOTAD via Zn Complexation in the Absence of Oxygen and
Light. ACS Energy Lett. 2020, 5, 1271−1277.
F
https://dx.doi.org/10.1021/acs.inorgchem.0c02624
Inorg. Chem. XXXX, XXX, XXX−XXX