A thiourea-functionalized metal-organic macrocycle for the catalysis of Michael additions and prominent size-selective effect

Article abstract of DOI:10.1039/c6dt04299f

A discrete tetranuclear thiourea-based metal-organic macrocycle (MOM) with a large size was constructed by a well-designed organic ligand and nickel(ii) ions via self-assembly. Incorporating thiourea groups as hydrogen-bond donors into a metal-organic com

Full text of DOI:10.1039/c6dt04299f

View Article Online
View Journal
Dalton
Transactions
Accepted Manuscript
This article can be cited before page numbers have been issued, to do this please use: L. Yang, L. Zhao,
Z. Zhou, C. He, H. Sun and C. Duan, Dalton Trans., 2017, DOI: 10.1039/C6DT04299F.
This is an Accepted Manuscript, which has been through the
Volume 45 Number
1 7 January 2016 Pages 1–398
Royal Society of Chemistry peer review process and has been
accepted for publication.
Dalton
Transactions
Accepted Manuscripts are published online shortly after
An international journal of inorganic chemistry
www.rsc.org/dalton
acceptance, before technical editing, formatting and proof reading.
Using this free service, authors can make their results available
to the community, in citable form, before we publish the edited
article. We will replace this Accepted Manuscript with the edited
and formatted Advance Article as soon as it is available.
You can find more information about Accepted Manuscripts in the
author guidelines.
Please note that technical editing may introduce minor changes
to the text and/or graphics, which may alter content. The journal’s
standard Terms & Conditions and the ethical guidelines, outlined
in our author and reviewer resource centre, still apply. In no
event shall the Royal Society of Chemistry be held responsible
for any errors or omissions in this Accepted Manuscript or any
consequences arising from the use of any information it contains.
ISSN 1477-9226
PAPER
Joseph T. Hupp, Omar K. Farha et al.
Efficient extraction of sulfate from water using
framework
a Zr-metal–organic
rsc.li/dalton

Please do not adjust margins
Dalton Transactions
Page 1 of 8
View Article Online
DOI: 10.1039/C6DT04299F
Journal Name
ARTICLE
A Thiourea-Functionalized Metal-Organic Macrocycle for Catalysis
of Michael Additions and Prominent Size-Selective Effect
Received 00th January 20xx,
Accepted 00th January 20xx
Lu Yang, Liang Zhao, Zhen Zhou, Cheng He*, Hui Sun and Chunying Duan
A discrete tetranuclear thiourea-based metal-organic marocycle (MOM) with large size was constructed by the well-
designed organic ligand and metal ions nickel(II) via self-assembly. Incorporating thiourea groups as hydrogen-bond
donors into the metal-organic complex system leads to a new approach for synthesizing functionalized heterogeneous
catalysts, not only introduces coordination sites serving as chelators, but also overcomes the issues of self-association by
intermolecular H-bonding often occurring in homogeneous system. The packing structure of this material formed a
confined environment suitable for the access of substrate molecule dragged by the strong hydrogen bond interaction from
thiourea groups, and thus achieved the highly catalysis of Michael additions from nitrostyrenes to nitroalkanes with
remarkable yield and size-selectivity in heterogeneous phase. Additionally, a comparison of the IR spectrum of Ni−SPT to
the spectra of absorbed dimethyl malonate and β-nitrostyrene indicated that both the substrates β-nitrostyrene and
dimethyl malonate molecules were accessible into the cavity of the trimeric packing subunit.
DOI: 10.1039/x0xx00000x
www.rsc.org/
Crafts reactions,7 Baylis-Hillman reactions,8 and Michael
additions, as one of the representative methods for the
formation of new C-C bonds. The nucleophilic addition of
Introduction
The emerging young field of metal-organic macrocycles
(MOMs), a class of discrete molecular architectures, has
received tremendous attention.1 Because of their high
symmetry, facile control, and structural stability. MOMs are
represented as promising materials with various properties.
Their abundant structural configurations and diverse functions
can be accessed by judicious selection of different metal
centers and rational design of organic ligands.2,3 The open
faces of MOMs can provide adequate space that is accessible
to guest molecules, resulting in broad applications in gas
capture, molecular recognition and catalysis. The use of MOMs
as molecular building blocks represents a powerful approach
to construct microporous molecular materials that typically
display large void volumes and attractive properties with
chemical flexibility and good processability.4 MOMs have
shown excellent advantages for the rational building of
microenvironments isolated from the bulk solution, with size-
and shape-selective recognition of molecules.
nitrostyrenes and malonates to unique chemicals,9 by
activating hydrogen bonding donor thiourea groups as Lewis
acid catalysts, is of particular interest. Many pioneering works
have been reported to date, focusing on this reaction in a
homogeneous system.10 However, hydrogen bonding sites in
homogeneous system easily self-quench to form dimers or
oligomers, and usually have serious recycling issues. In this
sense, fixing the catalytic thiourea groups into the rigid
skeleton provides
a
good approach to construct
heterogeneous catalysts that could overcome these flaws.11
The confined inner spaces and more extensive distribution of
active sites in MOMs make them excellent candidates for use
as enzyme-reminiscent catalysts possessing the combined
advantages of homogeneous and heterogeneous catalysis, for
example, high activity and selectivity, as well as easy
separation and recycling.12
Through the construction strategy established, herein, a
new tetranuclear MOM containing eight thiourea sites has
been synthesized by the coordination of Ni ions. The
immobilization and aggregation of thiourea groups in this
MOM system maintains the hydrogen bond activity and thus
provides an opportunity to specifically interact with substrates
into its confined cavities via H-bonds.13 Catalysis studies have
carried out and testifies that Ni-based MOM is catalytically
active towards Michael additions of nitrostyrenes to
nitroalkanes on the heterogeneous state, and show size-
selective catalytic behavior for large scope of substrates.
Urea and thiourea derivatives are important ligands
because of their strong hydrogen bonding activity, which has
been intensively investigated in many fields,5 especially for
organocatalysis. Several reports have indicated the effect of
thiourea derivatives on the reactivity of bond-forming
transformations, including Diels-Alder cycloadditions,6 Friedel-
a. State Key Laboratory of Fine Chemicals, Dalian University of Technology Dalian,
116012, China.
E-mail: hecheng@dlut.edu.cn.
Electronic Supplementary Information (ESI) available: Details of the catalytic
experiments, crystallography in CIF and more figures for the structures and spectra
of measurements.. See DOI: 10.1039/x0xx00000x
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 1
Please do not adjust margins

Please do not adjust margins
Dalton Transactions
Page 2 of 8
View Article Online
DOI: 10.1039/C6DT04299F
ARTICLE
Journal Name
Figure 1. (a) Crystal structure of Ni
−
SPT showing the distorted
rectangular window; (b) the “V-shaped” conformation of
Ni SPT (c) packing pattern of Ni SPT displaying C3
symmetry in trimeric fashion; (d) the representation of the
developed confined space and opening windows. The H atoms,
anions and solvent molecules are omitted for clarity.
−
;
−
a
Scheme 1 Design of bifunctional thiourea groups in the ligand
SPT and the schematic representation of the connectivity of Ni
ions and ligands via self-assembly.
Results and discussion
Notably, the Ni−SPT packs in a trimeric fashion without
The tridentate ligand SPT contains functional thiourea groups
that act as both coordination sites and hydrogen-bond donors.
The mixture of NiSO4∙6H2O and SPT was heated in DMF at
interlocking, forming a relatively confined space via the
obvious π∙∙∙π interaction with C3 symmetry. The macrocycles
may be regarded as opening windows, offering access to
molecules of a suitable size (Figure 1c). Each trimeric structure
is further packed into a three-dimensional network with one-
dimensional channels, as evident in Figure 2. The cavities have
a height of approximately 8.84 Å and width of 10.02 Å. When
viewed along different directions, the three-dimensional
packing structure exhibits various cavities with specific sizes.
70 °C for 2 h, and dark-brown crystals of Ni−SPT were
crystallized in 70% yield via evaporation under ambient
conditions after one week. Single crystal structural analysis
demonstrated that Ni
system with the R-3c space group. The asymmetric unit of
Ni SPT includes two crystallographically independent Ni(II)
−SPT crystallizes in a hexagonal crystal
−
ions and two independent SPT ligands, together with a quarter
2-
of SO4 anions, four lattice DMF, and three water molecules.
The assembly of four Ni ions and four SPT ligands forms a
macrocycle that exhibits a distorted rectangular window with
dimensions of 27.3× 9.7 Å2 (Figure 1a). Two Ni atoms and two
S atoms from the sulfone groups are positioned at the vertices
of a rectangle with a diagonal distance of 25.3 Å. Given the
flexibility of the SPT ligand (with angles between the two
planes involving benzene and sulfone groups, ranging from
102.63° to 112.07°), Ni−SPT is nonplanar and displays a “V-
shaped” conformation when viewed along the a axis, with the
angle of 111.24° between the two planes (Figure 1b), and the
four ligands located in an alternating up-and-down fashion.
Each Ni center is six-coordinated by two tridentate chelators
from two different ligands—two S atoms from the thiourea
groups, two N atoms from hydrazine groups and two N atoms
from pyridine—forming an overall octahedral configuration.
The average bond distances of the Ni−N and Ni−S bonds are
1.974−2.104 Å and 2.344−2.394 Å, respectively, within the
range of the reported Ni(II) compounds.14 The S−C bond
distances in the thiourea groups range from 1.667 to 1.750 Å;
these bonds are longer than the analogous bond in free
thiourea (1.57 Å), which is primarily attributed to the
coordination of the S atoms. The average C−N bond distances
are similar to that of free thiourea.
Figure 2. (a) The represented cavities of the packing mode of
Ni−SPT; (b) the packing diagram of one-dimensional channels
consolidated by the trimers viewed along a axis.
2 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins

Please do not adjust margins
Dalton Transactions
Page 3 of 8
View Article Online
DOI: 10.1039/C6DT04299F
Journal Name
ARTICLE
MeO2C CO2Me
NO2
Table 1. Michael reaction of various substituted nitrostyrenes
and dimethyl malonate in the presence Ni
heterogeneous catalyst.[a]
MeO2C
CO2Me
3a
NO2
−SPT as the
(2 equiv)
catalyst (2.5 mol%)
toluene, rt
2a
4a
MeO2
C
CO2Me
NO2
MeO2
(2 equiv)
C
CO2Me
NO2
R
catalyst (2.5mol%)
toluene, rt
R
MeO2C
CO2Me
NO2
MeO2C
CO2Me
NO2
MeO2C
CO2Me
NO2
Cl
4c, 98%
Cl
Cl
4d, 90%
Cl
4b, 93%
MeO2C
CO2Me
MeO2C
CO2Me
NO2
MeO2C
CO2Me
NO2
NO2
H3C
N
O
4f, 77%
4g, 42%
4e,79%
MeO2
C
CO2Me
NO2
MeO2C
CO2Me
NO2
MeO2
C
CO2Me
NO2
4h, 78%
4i, 82%
4j, 80%[b]
[a] Reaction conditions: nitrostyrenes (0.2 mmol), dimethyl malonate
(0.4 mmol), 2.5 mol% Ni-SPT as catalyst, 5 mol% TEA and 4 mL dried
toluene, 60 h, 25 °C; [b] The solvent was used 0.4 mL dried CH2Cl2
instead of toluene. All the yields were monitored by 1H-NMR spectra
of the crude product after reaction.
Figure 3. (a) Catalytic traces of Michael addition performed
with TEA only (cyan) and coexistence of TEA with 1.25 mol%
(blue), 2.5 mol% (red) or 5 mol% (black) of Ni−SPT under the
same conditions with different reaction times; (b) The linear
reaction trace indicates that the catalysis obeys a first-order
reaction rate constant and the constants have a linear
relationship of the calculated rate constants with the amount
of catalyst Ni−SPT.
relationship with the amount of the catalyst Ni−SPT. The
removal of the catalyst after 4 h terminated the reaction, and
the filtrate afforded 8% additional conversion over the
remaining 56 h of reaction time (Figure S8), and the additional
conversion is accordance with the catalytic behaviour that
performed only in the presence of 5 mol% TEA (Figure 3a, cyan
line). This result demonstrates that no active species has been
The potential catalytically active thiourea sites are distributed
within or on the surface of the cage-like cavity. Due to its large
volume, the cavity and the accessible channel can be inhabited
by two or more molecules, together with the extensive
distribution of the thiourea sites, which may attract and
activate substrates with other functional groups via these
strong hydrogen bond interactions,15 providing an ideal
leached into the reaction system, and thus Ni
heterogeneous catalyst for the Michael reaction. Grinding the
Ni SPT crystals into a small size, the catalytic reaction gives
−SPT is a true
−
platform for Ni−SPT to display the catalytic reaction.
the same yield under the same conditions, suggesting that the
The Michael reaction between nitrostyrenes and
malonates is particularly interesting, since this reaction
represents a convenient approach and is the most widely used
strategy for the synthesis of the nitroalkane products and their
derivatives.16 The versatile and synthetically diverse
intermediates transformed via Michael reactions provide a
wide range of industrial materials in organic synthesis.17
According to previous report, the main mechanistic proposal
for this reaction reveals the necessity need of a key functional
group to activate the electrophiles via H-bonding to the nitro
group.15 In this regard, the catalytic reaction was performed
neat with one equivalent of β-nitrostyrene (2a) and two
equivalents of dimethyl malonate (3a) in dry toluene, in the
size of the catalyst has no effect to the catalysis directly.
Figure 4. (a) Histogram of yields for the Michael reactions
between β-nitrostyrene and four malonates with different
presence of 5 mol% of TEA and 2.5 mol% of the Ni−SPT as the
prospective hydrogen-bond-donating catalyst at room
temperature (Figure 3). Almost complete conversion (>99%) to
the desired Michael adduct (4a) was observed after 60 h. The
ester groups in the presence of catalysts Ni
cyan) and Ni PDT (5 mol%, orange) after 48 h reaction; (b)
Crystal structure of Ni PDT
−SPT (2.5 mol%,
−
−
.
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 3
Please do not adjust margins

Please do not adjust margins
Dalton Transactions
Page 4 of 8
View Article Online
DOI: 10.1039/C6DT04299F
ARTICLE
Journal Name
To further investigate this hypothesis, we immersed the
desolvated catalyst in CH2Cl2 solution containing β-
a
nitrostyrene or dimethyl malonate for 3 days. The filtrated
solid was then washed with toluene several times to remove
any residual substrate on the surface. A comparison of the IR
spectrum of Ni−SPT to the spectra of absorbed dimethyl
malonate and β-nitrostyrene shows the splitting of the peak at
3053 cm-1 (Figure 5), which is attributed to the N=O stretching
vibration, and is red-shifted compared to the corresponding
peak in the spectrum of free β-nitrostyrene (3114 cm-1).
Additionally, the emerging peak at 1736 cm-1 (in blue line) of
dimethyl malonate impregnated spectrum is attributed to the
characteristic peak of the C=O stretching vibration and exhibits
a red shift from 1742 cm-1 (for free dimethyl malonate). The
results suggested that both β-nitrostyrene and dimethyl
malonate can be adsorbed in the cavity of the trimeric packing
Figure 5. The solid state IR spectra of fresh Ni−SPT (black),
Ni−SPT impregnated with a toluene solution of β-nitrostyrene
(pink) and dimethyl malonate (blue).
Ni−
SPT and further activated by the thiourea groups.19
A referential complex, which has the same coordination
mode and contains identical difunctional thiourea groups
(Figure 4b), was synthesized to explore whether the efficient
transformation occurred on the surface or within the cavity.
Due to the restriction of the ligand length and flexibility,
Control experiments showed low reaction yields in the
absence of Ni SPT with only 5 mol% of TEA, and also in the
−
presence of free SPT ligand, in both heterogeneous and
homogeneous states. Based on the results in Table S1, we
deemed that the Ni ions and thiourea groups act synergistically
in the catalytic process.18 In addition, the Ni ions is the typical
Lewis acid sites and the metal coordination may lead to the
enhancement of the acidity of the thiourea groups. At this
point, the combination of Ni(II) centers and thiourea functional
groups within an MOM system is a promising approach to
achieve high reaction efficiency and size selectivity in
heterogeneous catalysis.
Ni−PDT possesses an [M2L2] helical configuration with a
smaller cavity and compact distribution of thiourea groups.
The catalytic experiments were then performed under the
same reaction conditions but using Ni
heterogeneous catalyst. Relative to the results obtained from
Ni SPT, Ni PDT showed less catalytic efficiency to this Michael
addition (>99% vs 41% yield over 60 h for Ni SPT and Ni PDT,
−
PDT as
a
−
−
−
−
respectively). In addition, an obvious decrease of yields was
observed when the carbon chain length of malonates was
increased. These comparative results suggest that the cavity
size, together with the active site distribution influences the
contact and attraction of substrates inside the confined space
of the catalyst, thus substantially affecting the catalyst
reactivity.
Ni−SPT catalyst can be reused for six catalytic cycles
without significant loss of catalytic activity (Table S2). The
PXRD pattern of the used catalyst is consistent with those of
fresh Ni−SPT suggesting that the main skeleton is preserved
(Figure S9). Various nitrostyrenes were synthesized as
substitutive substrates to evaluate the generalization of the
catalytic results with 3a (Table 1). The Michael additions of
nitrostyrenes with electron-withdrawing (2b-2d) or donating
groups (2e, 2f) all afforded good to excellent yields in the
Conclusions
presence of Ni−SPT, except for the extremely strong electron-
In conclusion, we have developed a new thiourea-containing
MOM that represents an effective hydrogen-bond-donating
catalyst for Michael additions under mild conditions in the
heterogeneous phase. The immobilization and extensive
distribution of functional thiourea groups into the MOM
system not only introduces coordination sites serving as
chelators, but also results in strong hydrogen bond
interactions with substrates. The packing pattern of the
structure defines a unique confined space that enables the
entry of suitable substrates, leading to the high catalytic
efficiency and size-selectivity of the reaction. This work
provides a new substrate-accessible material that can be
incorporated with activated groups as heterogeneous
catalysts.
donating NMe2 group, which showed a large decline of the
reaction yield (42%). These catalytic results of the Michael
reaction between β-nitrostyrene and dimethyl malonate are
comparable with other reported catalysts containing
urea/thiourea groups or Ni-based complex performed in
homogeneous state (Table S3).
We next examined the scope of this class of Michael
reactions using the Ni−SPT catalyst and a series of malonates
under the same reactive conditions (Figure 4a). With varying
the carbon chain length in the ester groups, the size of the
malonates was evidently increased. As the ester groups were
changed from methyl to ethyl, propyl and tert-butyl ester, the
yields of the Michael reaction decreased gradually after 48 h
reaction from 51% to 42% and 38%, respectively. Both the
size-selective catalytic properties and the efficiency of the
catalytic reaction suggested that the reactions was displaced
within the cavities of the catalyst.
Experimental
4 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins

Please do not adjust margins
Dalton Transactions
Page 5 of 8
View Article Online
DOI: 10.1039/C6DT04299F
Journal Name
ARTICLE
Materials and Methods All chemicals were of reagent grade quality obtained from commercial sources and used without
Scheme 2. Synthetic routine of ligands SPT and PDT
.
of a catalytic amount of DMAP (4-dimethylaminopyridine, 2.68
mg, 1 mol%) in 1 mL ethanol. The reaction mixture was kept in
the ice bath for 5 min, and was then allowed to reach room
temperature. After evolution of gas from the reaction mixture
had ceased, the reaction mixture was stirred for a further 2 h
at room temperature and then evaporated in vacuum. The
pure product was obtained by silica gel column
chromatography (ethyl acetate/dichloromethane, 1:4 as an
further purification. 4,4’-sulfonylbis(isothiocyanatobenzene)
was purchased from Acros. The elemental analyses of C, H and
N were performed on a Vario EL III elemental analyzer. IR
spectra were recorded as KBr pellets on a NEXUS instrument.
Thermogravimetric analyses (TGA) were carried out at a ramp
rate of 10 oC min-1 in nitrogen flow with a SDTQ600 instrument.
1H NMR spectra were measured on a Varian INOVA 400M
spectrometer. Their peak frequencies were referenced versus
an internal standard (TMS) shifts at 0 ppm for 1H NMR.
Scanning electron microscopy (SEM) images were taken with a
NOVA NanoSEM 450 microscope. HPLC analysis was
performed on Agilent 1100 using a Chiral PAk AD−H column
and UV detector (254 nm) purchased from Daicel Chemical
Industries, Ltd.
1
eluent). Yield: 0.275 g, 65%. H NMR (CDCl3, 400 MHz, ppm):
7.33 (t, J = 8.1 Hz, 1H, ArH), 7.13 (d, J = 8.1 Hz, 2H, ArH), 7.07 (s,
1H, ArH).
N,N’-(1,3-phenylene)bis(hydrazinecarbothioamide) (c)
:
A
mixture solution of 80% hydrazine hydrate (2.50 g, 40 mmol)
and 4,4’-sulfonylbis(isothiocyanatobenzene) (0.192 g, 1.0
mmol) in methanol (10 mL) was stirred for 5 h at the room
temperature. The precipitate was collected by filtration,
washed with methanol and dried in vacuum. Yield: 0.179 g,
70%. 1H NMR (DMSO-d6, 400 MHz, ppm): 9.15 (s, 2H, NH), 7.91
(s, 1H, ArH), 7.43 (s, 2H, ArH), 7.20 (t, J = 8.0 Hz, 1H, ArH), 4.80
(s, 2H, NH), 3.95 (s, 4H, NH).
Preparation
1,1’-(4,4’-sulfonylbis(4,1-phenylene))dithiourea (a): A mixture
solution of 80% hydrazine hydrate (2.50 g, 40 mmol) and 4,4’-
sulfonylbis(isothiocyanatobenzene) (0.332 g, 1.0 mmol) in
methanol (20 mL) was stirred for 5 h at the room temperature.
The precipitate was collected by filtration, washed with
methanol and dried in vacuum. Yield: 0.30 g, 76%. 1H NMR
(DMSO-d6, 400 MHz, ppm): 9.47 (s, 4H, NH2), 8.21-7.94 (m, 4H,
ArH), 7.91-7.71 (m, 4H, ArH), 2.89 (s, 2H, Ar-NH), 2.73 (s, 2H,
Ar-NH).
Ligand
PDT
:
N,
N’-(1,
3-phenylene)bis(hydrazine-
carbothioamide) (0.256 g, 1.0 mmol) was added to a methanol
solution (20 mL) containing 2-pyridinecarboxaldehyde (0.257 g,
2.40 mmol). After 5 drops of acetic acid was added, the
mixture was refluxed overnight at 70 oC. The yellow product
was collected by filtration, washed with methanol and dried in
vacuum. Yield: 0.26 g, 60%. Anal calc. For C20H18N8S2: H 4.17, C
Ligand SPT
: 1,1’-(4,4’-sulfonylbis(4,1-phenylene))dithiourea
(0.396 g, 1.0 mmol) was added to a methanol solution (20 mL)
containing 2-pyridinecarboxaldehyde (0.257 g, 2.40 mmol).
After 5 drops of acetic acid was added, the mixture was
1
55.28, N 25.78%. Found: H 3.99, C 55.42, N 25.66%. H NMR
(DMSO-d6, 400 MHz, ppm): 12.07 (s, 2H, NH), 10.30 (d, J = 6.7
Hz, 2H, NH), 8.59 (d, J = 4.3 Hz, 2H, ArH), 8.47 (d, J = 8.0 Hz, 2H,
ArH), 8.20 (d, J = 4.3 Hz, 2H, CH=N), 7.92-7.83 (m, 2H, ArH),
7.81 (d, J = 1.9 Hz, 1H, ArH), 7.46 (dd, J = 7.1, 1.8 Hz, 2H, ArH),
7.43-7.32 (m, 3H, ArH). 13C NMR (DMSO-d6, 100 MHz, ppm):
176.30, 153.07, 149.27, 143.07, 138.78, 136.53, 127.55, 124.25,
123.35, 123.09, 120.68.
o
refluxed overnight at 70 C. The yellow product was collected
by filtration, washed with methanol and dried in vacuum. Yield:
0.344 g, 60%. Anal calc. For C26H22N8O2S3: H 3.85, C 54.33, N
19.49%. Found: H 3.79, C 54.89, N 19.32%. 1H NMR (DMSO-d6,
400 MHz, ppm): 12.28 (s, 2H, NH), 10.44 (s, 2H, NH), 8.60 (s, 2H,
CH=N), 8.41 (d, J = 7.9 Hz, 2H, ArH), 8.22 (s, 2H, ArH), 7.97 (d, J
= 7.3 Hz, 8H, ArH), 7.88 (s, 2H, ArH), 7.42 (s, 2H, ArH). 13C NMR
(DMSO-d6, 100 MHz, ppm): 175.96, 152.80, 149.37, 143.89,
143.59, 137.16, 136.58, 127.47, 125.58, 124.45, 120.77.
1,3-diisothiocyanatobenzene (b)20: 0.238 g (2.20 mmol) 1,3-
benzendiamine was dissolved in 5 mL ethanol. CS2 (3.34 g, 44
mmol) and Et3N (0.444 g, 4.40 mmol) were added while
stirring, and the reaction mixture cooled on an ice bath after
30 min at room temperature. Boc2O (0.950 g, 4.36 mmol) was
dissolved in 1 mL ethanol and added followed by the addition
Ni−SPT: A mixture of NiSO4∙6H2O (0.026 g, 0.10 mmol) and
ligand SPT (0.057 g, 0.10 mmol) was dissolved in 20 mL DMF
with strong stirring at 70 oC for 2 h. Then the solution was
filtrated after cooled to room temperature. Brown block
crystals were obtained via evaporation after one week. Yield:
80%. Anal calc. For C128H149N40O24Ni4S12.5: H 4.59, C 47.05, N
17.14, S 12.26%. Found: H 4.43, C 46.75, N 17.08, S 12.18%.
Ni−PDT: A mixture of Ni(BF4)2∙6H2O (0.034 g, 0.10 mmol) and
ligand PDT (0.04 3g, 0.10 mmol) was dissolved in 20 mL
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 5
Please do not adjust margins

Please do not adjust margins
Dalton Transactions
Page 6 of 8
View Article Online
DOI: 10.1039/C6DT04299F
ARTICLE
Journal Name
acetonitrile with strong stirring at 70 oC for 2 h. Then the distances in DMF molecules were constrained at ideal values.
solution was filtrated after cooled to room temperature.
Table 2. The crystal data of Ni−SPT and Ni−PDT.
The charge of the whole skeleton was balanced by the
deprotonated of three and half protons on the thiourea groups
(seven protons on all thiourea groups), thus only one half
occupied proton were fixed on the related nitrogen atom. The
distance of one S-O bond of the partly occupied sulphate anion
is fixed as ideal value, and the thermal parameters on adjacent
atoms of the sulphate anion were restrained to be similar. The
SQUEEZE subroutine in PLATON was used. The size of solvent-
accessible void is 59895 and the recovered number of
Compounds
Ni−SPT
Ni−PDT
Formula
C128H149N40O24Ni4S12.5 C50H52.5N21O0.75Ni2S4B4F16
Formula weight
3267.45
123(2)
1552.53
200(2)
T/K
Crystal system
Trigonal
R-3c
Orthorhombic
Fdd2
electrons is 11025. For Ni−PDT, it contains two integrated
species with four PDT ligands and four Ni ions, together with
Space group
-
a/Å
b/Å
c/Å
V/Å3
Z
31.3107(19)
31.3107(19)
145.863(18)
123840(21)
18
48.447(9)
51.450(12)
22.862(5)
56986(20)
32
seven acetonitrile molecules, four lattice water and eight BF4
anions within an asymmetry unit. Two boron atoms and eight
-
fluorine atoms of the BF4 anions were disordered into two
parts with each S. O. F. fixed as 0.5. And there are four fluorine
atoms were occupied as 0.25, while twenty-eight were
occupied as 0.5 and the rest thirteen-three fluorine atoms
were occupied as 1, forming the total thirty-two fluorine
D
calc/Mg m–3
0.789
1.448
-
-
μ/mm–1
0.408
0.739
atoms in eight BF4 anions. Several bond distances in BF4
anions were constrained at ideal values.
F(000)
30618
25264
Rint
0.1829
0.1509
Acknowledgements
GOF
0.950
0.894
R [I > 2σ(I)]a
R indices
(all data)b
CCDC NO.
R1 = 0.1110
R1 = 0.0885
This work was supported by NSFC 21531001 and 21501019,
and the Basic Research Program of China (Grant no.
2013CB733700).
wR2 = 0.2827
wR2 = 0.2397
1474347
1474346
aR1 = Σ||Fo| – |Fc||/Σ|Fo|; bwR2 = Σ[w(Fo2 – Fc2)2]/Σ[w(Fo2)2]1/2. The formula
and all formula-devrived parameters (formula weight, density, mu, F000)
are calculated without the masked solvent.
Notes and references
1
2
a) B. H. Northrop, Y. R. Zheng, K. W. Chi, P. J. Stang, Acc.
Chem. Res. 2009, 42, 1554; b) N. C. Gianneschi, M. S. Maser,
C. A. Mirkin, Acc. Chem. Res. 2005, 38, 825; c) J.-M. Lehn,
Chem. Soc. Rev. 2007, 36, 151; d) H. Vardhan, M. Yusubov, F.
Verpoort, Coord. Chem. Rev. 2016, 306, 171.
Reddish block crystals were obtained through diffusing diethyl
ether into the above filtrate after one week. Yield: 52% (based
on the crystal dried in vacuum). Anal calc. For
C50H52.5N21O0.75Ni2S4B4F16: H 3.40, C 38.68, N 18.94, S 8.26%.
Found: H 3.12, C 36.78, N 17.63, S 8.64%.
a) M. X. Han, D. M. Engelhard, G. H. Clever, Chem. Soc. Rev.
2014, 43, 1848; b) M. Fujita, Chem. Soc. Rev. 1998, 27, 417;
c) D. L. Caulder, K. N. Raymond, Acc. Chem. Res. 1999, 32
975.
T. R. Cook, P. J. Stang, Chem. Rev. 2015, 115, 7001.
a) S. H. Cho, B. Q. Ma, S. T. Nguyen, J. T. Hupp, T. E. Albrecht-
Schmitt, Chem. Commun. 2006, 2563; b) J. I. García, B. López-
Sánchea, J. A. Mayoral, Org. Lett. 2008, 10, 4995; c) R.
Custelcean, P. V. Bonnesen, N. C. Duncan, X. H. Zhang, L. A.
Watson, G. V. Berkel, W. B. Parson, B. P. Hay, J. Am. Chem.
Soc. 2012, 134, 8525.
,
3
4
Crystallography
X-ray intensity data were measured on a Bruker SMART APEX
CCD-based diffractometer (Mo–Kα radiation, λ = 0.71073 Å)
using the SMART and SAINT programs.21, 22 The crystal data
were solved by direct methods and further refined by full-
matrix least-squares refinements on F2 using the SHELXL-2014
software and an absorption correction was performed using
the SADABS program.23 The remaining atoms were found from
successive full-matrix least-squares refinements on F2 and
Fourier syntheses. Except some partly occupied atoms, non-H
atoms were refined with anisotropic displacement parameters.
The hydrogen atoms within the ligand backbones were fixed
geometrically at calculated distances and allowed to ride on
the parent non-hydrogen atoms. The crystal data were listed in
Table 2.
5
a) A. G. Doyle, E. N. Jacobsen, Chem. Rev. 2007, 107, 5713; b)
R. Custelcean, Chem. Commun. 2013, 49, 2173. c) M.
Karbarz, J. Romański, Inorg. Chem. 2016, 55, 3616.
6
7
a) A. Wittkopp, P. R. Schreiner, Chem. Eur. J. 2003,
S. Rajaram, M. S. Sigman, Org. Lett. 2005, , 5473.
a) H. Li, Y. Q. Wang, L. Deng, Org. Lett. 2006, , 4063; b) B.
9, 407; b)
7
8
Török, M. Abid, G. London, J. Esquibel, M. S. Török, C.
Mhadgut, P. Yan, G. K. S. Prakash, Angew. Chem. Int. Ed.
2005, 44, 3086.
8
9
a) Y. Sohtome, A. Tanatani, Y. Hashimoto, K. Nagasawa,
Tetrahedron Lett. 2004, 45, 5589; b) J. M. Brunel, Chem. Rev.
2005, 105, 857; c) G. W. Amarante, M. Benassi, H. M. S.
Milagre, A. A. C. Braga, F. Maseras, M. N. Eberlin, F. Coelho,
Chem. Eur. J. 2009, 15, 12460.
For Ni−SPT, there are two SPT ligands and two Ni ions
within an asymmetry unit, together with three lattice water,
four DMF molecules and a quarter of SO42- anion. Several bond
T. Okino, Y. Hoashi, T. Furukawa, X. N. Xu, Y. Takemoto, J.
Am. Chem. Soc. 2005, 127, 119.
6 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins

Please do not adjust margins
Dalton Transactions
Page 7 of 8
View Article Online
DOI: 10.1039/C6DT04299F
Journal Name
ARTICLE
10 a) Y. Kim, S. Some, H. Lee, Chem. Commun. 2013, 49, 5702;
b) H. M. Li, Y. Wang, L. Tang, L. Deng, J. Am. Chem. Soc. 2004,
126, 9906.
11 a) E. A. Hall, L. R. Redfern, M. H. Wang, K. A. Scheidt, ACS
Catal. 2016,
Wang, P. C. Junk, J. Mater. Chem. A. 2015,
6
, 3248; b) A. A. Tehrani, S. Abedi, A. Morsali, J.
, 20408; c) P. W.
3
Siu, Z. J. Brown, O. K. Farha, J. T. Hupp, K. A. Scheidt, Chem.
Commun. 2013, 49, 10920; d) S. M. Cohen, Z. J. Zhang, J.
Boissonnault, Inorg. Chem. 2016, 55, 7281; e) J. V. Alegre-
Requena, E. Marqués-López, R. P. Herrera, D. D. Díaz,
CrystEngComm, 2016, 18, 3985; f) J. M. Robert, B. M. Fini, A.
A. Sarjeant, O. K. Farha, J. T. Hupp, K. A. Scheidt, J. Am. Chem.
Soc. 2012, 134, 3334; g) Z. F. Ju, S. C. Yan, D. Q. Yuan, Chem.
Mater., 2016, 28, 2000; h) C. M. McGuirk, M. J. Katz, C. L.
Stern, A. A. Sarjeant, J. T. Hupp, O. K. Farha, C. A. Mirkin, J.
Am. Chem. Soc., 2015, 137, 919.
12 P. Howlader, P. Das, E. Zangrando, P. S. Mukherjee, J. Am.
Chem. Soc. 2016, 138, 1668.
13 Y. Liu, R. Zhang, C. He, D. B. Dang, C. Y. Duan, Chem.
Commun. 2010, 46, 746.
14 a) S. Decurtins, H. W. Schmalle, P. Schneuwly, J. Ensling, P.
Gutlich, J. Am. Chem. Soc. 1994, 116, 9521; b) J. W. Ciszek, Z.
K. Keane, L. Cheng, M. P. Stewart, L. H. Yu, D. Natelson, J. M.
Tour, J. Am. Chem. Soc. 2006, 128, 3179.
15 T. Okino, Y. Hoashi, Y. Takemoto, J. Am. Chem. Soc. 2003,
125, 12672.
16 T. Okino, Y. Hoashi, T. Furukawa, X. N. Xu and Y. Takemoto, J.
Am. Chem. Soc., 2005, 127, 119.
17 O. M. Berner, L. Tedeschi and D. Enders, Eur. J. Org. Chem.,
2002, 1877.
18 X. J. Wang, J. Li, Q. Y. Li, P. Z. Li, H. Lu, Q. Y. Lao, R. Ni, Y. H.
Shi, Y. L. Zhao, CrystEngComm. 2015, 17, 4632.
19 a) P. Y. Wu, C. He, J. Wang, X. J. Peng, X. Z. Li, Y. L. An, C. Y.
Duan, J. Am. Chem. Soc. 2012, 134, 14991; b) T. Inkuma, Y.
Hoashi, Y. Takemoto, J. Am. Chem. Soc. 2006, 128, 9413.
20 H. Munch, J. S. Hansen, M. Pittelkow, J. B. Christensen, U.
Boas, Tetrahedron Lett. 2008, 49, 3117.
21 SMART Data collection software, version 5.629; Bruker AXS
Inc.: Madison, WI, 2003.
22 SAINT Data reduction software, version 6.45; Bruker AXS
Inc.: Madison, WI, 2003.
23 G. M. Sheldrick, SHELX-97: Program for crystal structure
analysis; University of Göttingen: Göttingen, Germany, 1997.
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 7
Please do not adjust margins

Dalton Transactions
Page 8 of 8
View Article Online
DOI: 10.1039/C6DT04299F
Synopsis
A discrete tetranuclear metal-organic macrocycle (MOM) containing thiourea groups as hydrogen
bonding sites was prepared. The packing structure of this material formed a inner
microenvironment suitable for the access of substrate molecule dragged by strong hydrogen
bond interaction from thiourea groups, and thus achieved the highly catalysis of Michael
additions from nitrostyrenes to nitroalkanes with remarkable yield and size-selectivity in
heterogeneous phase.