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Hydrolysis Controlled Synthetic Strategy and Structural Variation of Hydroxyl-Metal Clusters and Metal-Organic Frameworks Based on Tripodal Ether-Linked 1,3,5-Tris(carboxymethoxy)benzene Jia-Yao Zhang, Xue-Li Ma, Zhao-Xi Wang, Xiang He, Min Shao, and Ming-Xing Li Cryst. Growth Des., Just Accepted Manuscript • DOI: 10.1021/acs.cgd.9b00010 • Publication Date (Web): 22 Feb 2019 Downloaded from http://pubs.acs.org on February 23, 2019
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Crystal Growth & Design
Hydrolysis Controlled Synthetic Strategy and Structural Variation of Hydroxyl-Metal Clusters and Metal-Organic Frameworks Based on Tripodal Ether-Linked 1,3,5-Tris(carboxymethoxy)benzene Jia-Yao Zhang,† Xue-Li Ma,† Zhao-Xi Wang,† Xiang He,† Min Shao,‡ and Ming-Xing Li*,† † Department ‡ Laboratory
of Chemistry, College of Sciences, Shanghai University, Shanghai 200444, China.
for Microstructures, School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China.
RECEIVED DATE
ABSTRACT: Eight novel coordination polymers were prepared by a tripodal ether-linked tricarboxylic acid: [Mn3(TCMB)2(H2O)4]n·4nH2O (1), [Cu3(TCMB)(μ3-OH)3]n·0.5nH2O (2), [Zn3.5(TCMB)2(μ2-OH)(H2O)4]n·2nH2O (3), [Zn2(TCMB)(4-abpt)(μ3-OH)]n·nH2O (4), [Cd2(TCMB)(pdta)(EtOH)(H2O)]n·2nH2O (5), [Co3(TCMB)2(bpee)3(MeOH) (H2O)5]n (6), and [Co4(TCMB)2(bpee)2(μ3-OH)2(H2O)2]n·12nH2O (7, 8) (H3TCMB = 1,3,5-tris(carboxymethoxy)benzene, 4-abpt = 4-amino-3,5-bis(4-pyridyl)-1,2,4-triazole, Hpdta = 4-(1H-tetrazol-5-yl)pyridine, bpee = 1,2-bis(4-pyridyl)ethene). These complexes were characterized by EA, IR, TGA, PXRD and single crystal XRD. H3TCMB is fully deprotonated, and flexible TCMB3– ligand exhibits nine coordination modes and various conformations. Complex 1 is a 2D coordination polymer constructing from [Mn(μ2-COO)2]n linear chain and [Mn2(μ2-COO)2(μ3-COO)2]n double-chain combined by hexadentate TCMB3– spacer. Complex 2 is a beautiful 2D sandwich-like network assembled by layered [Cu3(μ3-OH)3]n network and typical tripodal hexadentate TCMB3− ligand. Complex 3 is a 3D coordination polymer constructing from two distinct heptadentate TCMB3– ligands, in which the ether oxygen atoms take part in coordination. Complex 4 exhibits a 2D double-layered network built by tetranuclear zinc cluster [Zn4(μ2-COO)4(μ3-OH)2] pillared by pentadentate TCMB3– spacer and 4-abpt linker. Complex 5 displays a 3D architecture assembled by tridentate pdta– and heptadentate TCMB3– ligand with ether-oxygen coordination. Cobalt complexes 6–8 were prepared by similar reactions at slightly different temperature (85, 100 and 120 °C). Complex 6 is a 3D coordination polymer assembled by tridentate TCMB3– ligand. Complex 7 is a 3D porous MOF possessing tetranuclear cobalt cluster [Co4(μ2-COO)3(μ3-COO)2(μ3-OH)2] combined by hexadentate and tetradentate TCMB3– ligands. Complex 8 is a cluster-based 3D porous MOF, which is an isomer of 7 and contains different tetranuclear cluster [Co4(μ2-COO)6(μ3-OH)2] and pentadentate TCMB3– ligand. PXRD study reveals the hydrolysis reaction mechanism. A hydrolysis controlled synthesis strategy is suggested based on Ksp values of metal hydroxides. Their thermal stabilities were investigated. Complexes 1, 2, 7 and 8 present antiferromagnetic and/or ferromagnetic interactions. Their magneto-structural correlations are studied. Keywords: Coordination polymer; 1,3,5-Tris(carboxymethoxy)benzene; Crystal structure; Hydrolysis; Magnetism. purposeful design and controllable synthesis of CPs and INTRODUCTION Since 1990s, coordination
polymers
(CPs)
and
metal-organic frameworks (MOFs) have attracted much attention,1–5 not only for their intriguing architectural and topological varieties,6,7 but also for their multifunctional physical and chemical properties such as magnetism, luminescence, gas storage, catalysis, ferroelectricity and sensor.8–13 Although much effort has been paid on the
MOFs, it is still a great challenge to synthesize these functional complexes with interesting network structures and properties. To harvest novel CPs and MOFs, it depends on a variety of reaction parameters including metal ion, ligand, pH value, solvent, temperature, reagent ratio, additive, etc.14–18 There is no doubt that the structural attribution of an organic multidentate ligand plays a crucial
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role in controlling the complex structure as well as topology of the derived
framework.19–21
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the ligand to metal centers. Three ether oxygen atoms may
Moreover, similar
function as electron-donors forming hydrogen bonds to
reactants often result in completely different structures due
stabilize the network structure, even coordinate to metal
to the extreme sensitivity of self-assembly to the reaction
ions. Therefore H3TCMB is a potential valuable flexible
conditions. To date, the abundant examples of temperature-
tripodal ligand.
and solvent-dependent structural variation of coordination
Although H3TCMB was synthesized in 2002,40,41 its
polymers have been doccumented.22–24 In most cases,
coordination feature has rarely been investigated yet. Only
different structures lead to different functional properties.
four papers containing nine H3TCMB complexes were
Particularly, many coordination polymers have interesting
documented.41–44 In this work, we used five metal acetates
magnetic properties.25–27 The study related to their
reacted with H3TCMB and three N-heterocyclic auxiliary
magnetism and structures is very active. Paramagnetic
ligands in neutral aqueous solutions, successfully prepared
metal ions can form clusters, chains or sheets which can be
eight novel CPs and MOFs. These complexes exhibit
linked by bridging groups such as carboxylic, hydroxyl and
interesting 2D and 3D networks originating from the
N-heterocyclic groups to produce various coordination
versatile coordination modes and conformations of
Towards
H3TCMB. Hydrolysis reactions at different temperatures
these goals, a number of polycarboxylic acids have been
play important roles in constructing their hydroxyl-
employed to prepare magnetic coordination polymers,
containing metal clusters. By comparing the precipitation-
owing to the fact that carboxylic group has diverse binding
dissolution equilibrium constant Ksp values of MII(OH)2 (M
ability that can efficiently transmit magnetic interaction.30
= Mn, Co, Cu, Zn, Cd), we discuss their hydrolysis
polymers with varied magnetic
properties.28,29
Generally, rigid aromatic polycarboxylates can lead to predictable network structures and produce highly stable
procedures in detail. Scheme 1. H3TCMB and N-Heterocyclic Ligands
coordination polymers, which have been extensively
COOH
investigated to construct coordination polymers. By
O
contrast, flexible and semirigid polycarboxylates can adopt varied conformations and coordination modes suitable for metal geometric requirement and sensitive reaction
N HOOC
O
O
COOH
H3TCMB
H N N N N
Hpdta
conditions, which may afford unpredictable coordination polymers and uncommon frameworks.31–33 Recently, ether-linked
polycarboxylates
have
attracted
intense
attention in constructing coordination polymers, Because
N
NH2 N N N
N
N N
4-abpt
bpee
the freely rotating ether bond can bring conformational change and structural flexibility.34–36 In order to extend our research in ether-linked tetracarboxylate
EXPERIMENTAL SECTION
we
Materials and Methods. H3TCMB and N-heterocyclic
acid,
ligands were purchased from Jinan Henghua Sci. & Tec.
1,3,5-tris(carboxymethoxy)benzene (H3TCMB, Scheme 1),
Co. Ltd. (China). Elemental analyses (C, H, and N) were
for our study. In comparison with the intensively
carried out with a Vario EL-III analyzer. Infrared spectra
investigated rigid 1,3,5-benzenetricarboxylic acid, the
(KBr pellet) were recorded by a Nicolet A370 FT-IR
flexible H3TCMB has good ligating ability to metal ions
spectrometer in 400–4000 cm–1. Thermal analyses were
and exhibits additional interesting characteristics, such as
performed by a Netzsch STA 449C thermal analyzer at a
the freely rotating ether bonds and flexible tripodal
heating rate of 10°C min–1 in air. Powder X-ray diffractions
conformation. Three –O–CH2– groups can bend to enable
(PXRD) were completed on a Rigaku D/MAX-2550
chose
a
tripodal
ether-linked
complexes,37–39
tricarboxylic
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Crystal Growth & Design
diffractometer at a scanning rate of 5° min–1 in 5–50° (2θ).
[Cd2(TCMB)(pdta)(EtOH)(H2O)]n·2nH2O
(5).
A
Magnetic susceptibilities as a function of temperature in the
mixture of Cd(OAc)2·2H2O (0.20 mmol), H3TCMB (0.05
range of 2–300 K were measured on a Quantum Design
mmol), Hpdta (0.10 mmol), ethanol (4 mL) and water (4
MPMS-XL7 SQUID magnetometer at the magnetic field of
mL) was sealed in a Teflon-lined reactor (15 mL) and
1 kOe. Diamagnetic corrections were applied by using
heated at 85 °C for 72 h. Light yellow sheet crystals were
Pascal’s constants.
harvested in 54% yield. Anal. Calcd for C20H25N5O13Cd2: C,
Syntheses of Complexes 1–8.
31.27; H, 3.28; N, 9.11. Found: C, 30.42; H, 3.13; N, 9.35.
[Mn3(TCMB)2(H2O)4]n·4nH2O (1). A mixture of
IR: 3471m, 3090w, 2989w, 1579s, 1430s, 1326m, 1165s,
Mn(OAc)2·4H2O (0.20 mmol), H3TCMB (0.05 mmol),
1072m, 845m, 718s, 643m cm–1.
4-abpt (0.05 mmol), ethanol (4 mL) and water (4 mL) was
[Co3(TCMB)2(bpee)3(MeOH)(H2O)5]n (6). A mixture
sealed in a Teflon-lined reactor (15 mL) and heated at 100
of Co(OAc)2·4H2O (0.30 mmol), H3TCMB (0.05 mmol),
°C for 72 h. Light yellow sheet crystals were harvested in
bpee (0.10 mmol), methanol (4 mL) and water (4 mL) was
30%
for
sealed in a Teflon-lined reactor (15 mL) and heated at 85
C24H34O26Mn3: C, 31.91; H, 3.79. Found: C, 33.22; H, 3.85.
°C for 72 h. Pink sheet crystals were harvested in 44%
IR: 3389m, 2967w, 1615s, 1415s, 1334m, 1267m, 1170s,
yield. Anal. Calcd for C61H62N6O24Co3: C, 50.88; H, 4.34;
1079m, 821m, 726s, 629m cm–1.
N, 5.83. Found: C, 49.29; H, 4.52; N, 5.07. IR: 3190w,
yield
based
on
H3TCMB.
Anal.
Calcd
[Cu3(TCMB)(μ3-OH)3]n·0.5nH2O (2). A mixture of Cu(OAc)2·2H2O (0.20 mmol), H3TCMB (0.05 mmol),
3064w, 2909w, 1607s, 1417s, 1322m, 1260m, 1165s, 1077m, 832s, 715m, 554m cm–1.
4-abpt (0.05 mmol), ethanol (4 mL) and water (4 mL) was
[Co4(TCMB)2(bpee)2(μ3-OH)2(H2O)2]n·12nH2O (7). A
sealed in a Teflon-lined reactor (15 mL) and heated at 100
mixture of Co(OAc)2·4H2O (0.30 mmol), H3TCMB (0.05
°C for 72 h. Blue sheet crystals were harvested in 44%
mmol), bpee (0.10 mmol), methanol (4 mL) and water (4
yield. Anal. Calcd for C12H13O12.5Cu3: C, 26.31; H, 2.39.
mL) was sealed in a Teflon-lined reactor (15 mL) and
Found: C, 27.11; H, 2.81. IR: 3543s, 2932w, 1594s, 1430s,
heated at 100 °C for 72 h. Pink rod crystals were harvested
1260m, 1155s, 1074m, 937s, 812m, 724s, 507s
cm–1.
in 43% yield. Anal. Calcd for C48H68N4O34Co4: C, 38.93; H,
[Zn3.5(TCMB)2(μ2-OH)(H2O)4]n·2nH2O (3). A mixture
4.63; N, 3.78. Found: C, 40.45; H, 4.61; N, 3.98. IR:
of Zn(OAc)2·2H2O (0.20 mmol), H3TCMB (0.05 mmol),
3557w, 3380m, 3079w, 2936w, 1607s, 1416s, 1334s,
4-abpt (0.05 mmol), ethanol (4 mL) and water (4 mL) was
1154s, 1070s, 837s, 679m, 554m cm–1.
sealed in a Teflon-lined reactor (15 mL) and heated at 100
[Co4(TCMB)2(bpee)2(μ3-OH)2(H2O)2]n·5nH2O (8). A
°C for 72 h. Colorless sheet crystals were harvested in 24%
mixture of Co(OAc)2·4H2O (0.30 mmol), H3TCMB (0.05
yield. Anal. Calcd for C24H31O25Zn3.5: C, 30.40; H, 3.30.
mmol), bpee (0.10 mmol), methanol (4 mL) and water (4
Found: C, 31.15; H, 3.51. IR: 3444m, 3094w, 2934w,
mL) was sealed in a Teflon-lined reactor (15 mL) and
1598s, 1410s, 1302m, 1162s, 1082m, 838m, 731m cm–1.
heated at 120 °C for 72 h. Pink block crystals were
[Zn2(TCMB)(4-abpt)(μ3-OH)]n·nH2O (4). A mixture of
harvested in 36% yield. Anal. Calcd for C48H68N4O34Co4: C,
Zn(OAc)2·2H2O (0.20 mmol), H3TCMB (0.05 mmol),
38.93; H, 4.63; N, 3.78. Found: C, 40.11; H, 4.49; N, 3.87.
4-abpt (0.10 mmol), ethanol (4 mL) and water (4 mL) was
IR: 3596w, 3072w, 2931w, 1597s, 1421s, 1336m, 1163s,
sealed in a Teflon-lined reactor (15 mL) and heated at 85
1081m, 832m, 720m, 550m cm–1.
°C for 72 h. Light yellow sheet crystals were harvested in
X-ray Crystallography. Single crystals of 1–8 were
49% yield. Anal. Calcd for C24H22N6O11Zn2: C, 41.11; H,
selected for X-ray diffraction study. The crystal data were
3.16; N, 11.98. Found: C, 40.95; H, 3.07; N, 11.77. IR:
collected on a Bruker Smart Apex-II CCD diffractometer
3319m, 3095w, 2966w, 1608s, 1407s, 1292m, 1157s,
with graphite-monochromatic Mo-Kα radiation (λ =
1071m, 836s, 714s, 601m cm–1.
0.71073 Å) at 296 K. The determinations of crystal system, ACS Paragon Plus Environment
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orientation matrix, and cell dimensions were performed
Mn2···Mn2B distance of 4.645(2) Å. The 1D linear chain
according to established procedures. Their structures were
and double-chain are further connected by the aromatic
solved by direct methods.45 Non-hydrogen atoms were
ring of TCMB3− to form the final 2D network of complex 1,
refined anisotropically. Hydrogen atoms were placed
as depicted in Figure 1c. Previously, a binuclear complex
geometrically and refined using the riding model.
(H2bipy)[Mn2(HTCMB)2(H2O)8]·5H2O
Crystallographic data have been deposited with the
from bidentate HTCMB2– ligand.41
was
constructed
Cambridge Crystallographic Data Center with the CCDC numbers 1888154−1888161. Their key crystallographic data are summarized in Table 1. Selected bond distances
(a)
and angles are listed in Table S1 (Supporting Information). Hydrogen bonds are collected in Table S2. RESULTS AND DISCUSSION Crystal Structural Description. [Mn3(TCMB)2(H2O)4]n·4nH2O (1). Complex 1 is a 2D coordination polymer. The asymmetric unit contains one and a half crystallographically independent Mn(II) ions, a
(b)
TCMB3– ligand, two coordinated water molecules and two lattice water molecules (Figure 1a). Mn1 (0.5 occupancy) locates at the center of a symmetric octahedral geometry, coordinated by four carboxylic oxygens and two water molecules (O11, O11A). The Mn1−O9, Mn1−O10 and Mn1−O11 bond distances are 2.246(2), 2.137(2) and 2.187(2) Å, respectively. Mn2 adopts a distorted octahedral geometry, coordinated by five carboxylic oxygens and water O4 atom. Mn2−O4 bond distance is 2.199(4) Å. The carboxylic Mn2–O bond distances vary from 2.139(2) to
(c)
2.260(3) Å. Three carboxylic groups of H3TCMB are fully deprotonated. TCMB3− anion acts as a hexadentate ligand and adopts coordination mode I (Scheme 2), which possesses two bidentate syn-syn η1η1-μ2-carboxylic groups and a bidentate-bridging η1η2-μ3-carboxylic group. One η1η1-μ2-carboxylic group links Mn1 (0.5 occupancy) and Mn1A to form a 1D [Mn(μ2-COO)2]n linear chain (Figure 1b). Mn1···Mn1A distance is 4.645(2) Å. Another η1η1-μ2-carboxylic group and the η1η2-μ3-carboxylic group link Mn2 ions to form a 1D [Mn2(μ2-COO)2(μ3-COO)2]n double-chain. The η1η2-μ3-carboxylic group links Mn2 and Mn2A via O5 bridging atom with a Mn2···Mn2A distance of 3.537(1) Å, and binds to Mn2B via O3B terminal with a
Figure 1. (a) Coordination structure of 1, lattice water and hydrogen atoms are omitted for clarity. (b) 1D [Mn(μ2-COO)2]n chain (up), and 1D double-chain [Mn2(μ2-COO)2(μ3-COO)2]n (down). (c) 2D network. [Cu3(TCMB)(μ3-OH)3]n·0.5nH2O (2). Complex 2 is a 2D sandwich-like coordination polymer, which crystallizes in trigonal P-3 space group and has a C3 symmetric axis. The asymmetric unit contains an independent Cu(II) ion, 1/3 TCMB3– ligand, a μ3-OH– ligand, and 1/6 lattice water molecule. Cu1 adopts a square-pyramidal geometry (Figure 2a), coordinated by two carboxylic oxygens (O1A, O3) and
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Crystal Growth & Design
three hydroxyl oxygens (O2, O2A, O2B). Hydroxyl O2A
Complex 2 is the first example to exhibit perfect
atom occupies the apical position with a Cu1–O2A bond
tripodal coordination conformation of TCMB3− ligand. Due
distance of 2.266(5) Å. Other two hydroxyl Cu1–O2 and
to the flexibility of ether linkage, TCMB3− presents a
Cu1–O2B bond distances are 1.926(4) and 1.945(4) Å,
typical tripodal conformation with almost perpendicular
while O1A–Cu1–O3 and O2–Cu1–O2B bond angles are
dihedral angle (86.73º) between three carbethoxyl groups
159.7(2) and 175.8(1)°, respectively.
and central phenyl ring. TCMB3− is a hexadentate ligand, which
(a)
η1η1-μ
has
three
2-carboxylic
identical
bidentate
syn-syn
groups (mode II, Scheme 2). Each
TCMB3− captures six Cu(II) ions to afford a sandwich-like 2D [Cu3(TCMB)]n network (Figure 2b). The inner copper ions are further connected by μ3-hydroxyl groups to form a layered
[Cu3(μ3-OH)3]n
network
that
possesses
honeycomb-like 12-membered ring with the pore diameter of 6.479(2) Å (Figure 2c). The [Cu3(μ3-OH)3]n layer is sandwiched between two organic layers originating from (b)
the tripodal TCMB3− ligands. This combination produces a 2D porous sandwich-like network with the thickness of about 8.4 Å (Figure 2d). The identical 2D networks are parallel packed along the c-axis, as depicted in Figure S1 (Supporting Information). [Zn3.5(TCMB)2(μ2-OH)(H2O)4]n·2nH2O (3). Complex 3 is a 3D coordination polymer. The asymmetric unit
(c)
contains three and a half independent Zn(II) ions, two TCMB3– ligands, a μ2-OH– ligand, four H2O ligands and two lattice H2O molecules (Figure 3a). Zn1 adopts a tetrahedral geometry, coordinated by carboxylic O9 and O10 atoms, hydroxyl O8 atom, and water O11W atom. Zn2 adopts a distorted octahedral geometry, coordinated by two monodentate carboxylic groups (O5, O7), water O6W, hydroxyl O8, and two ether oxygen atoms (O3, O12). Zn2–O3 and Zn2–O12 bond distances are 2.528(4) and
(d)
2.487(6) Å, respectively. Previously, the phenomenon of ether oxygen coordination was observed in a Cu-TCMB complex, in which the Cu–O bond distance is 2.412(2) Å.42 Zn3 locates at the center of an octahedral geometry, coordinated by four carboxylic oxygens (O15, O16, O17, O19) on equatorial plane. Ether O14 and water O18W atoms occupy the axial positions with the O14–Zn3–O18W
Figure 2. (a) Coordination structure of 2. (b) Sandwichlike [Cu3(TCMB)]n network. (c) [Cu3(μ3-OH)3]n layer. (d) 2D porous sandwich-like network viewed along the c- and b-axes.
bond angle of 149.8(1)º and the Zn3–O14 distance of 2.402(3) Å. Zn4 (0.5 occupancy) is weakly coordinated by three carboxylic oxygens and two water molecules (O21W,
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Page 6 of 21
O6a). Five Zn4–O distances are in the 2.662(4)–2.859(4) Å
μ2-hydroxyl group connect Zn1, Zn2 and Zn3 to afford a
range, longer than normal coordination bond. Therefore,
complicate 3D coordination polymer (Figure 3b). Zn4 (0.5
Zn4 can be deemed as a charge counterion.
occupancy) has weak combination with five O-donors and balances the charge from μ2-OH– anion.
(a)
[Zn2(TCMB)(4-abpt)(μ3-OH)]n·nH2O (4). Complex 4 is a 2D double-layered coordination polymer. The asymmetric unit contains two independent Zn(II) ions, a TCMB3−, a 4-abpt, a μ3-OH− ligand and a lattice water molecule. Zn1 is surrounded by three carboxylic oxygens, pyridyl N1 and two hydroxyl oxygens (O3, O3A), completed an octahedral geometry (Figure 4a). Zn2 adopts a tetrahedral geometry, coordinated by two carboxylic oxygens, pyridyl N2 and hydroxyl O3 atoms. All the Zn−O bond distances vary from 1.944(3) to 2.216(3) Å, except a slightly longer Zn1−O4 bond (2.415(4) Å). Average Zn–N distance is 2.039(4) Å.
(b)
(a)
Figure 3. (a) Coordination structure of 3. (b) 3D framework. Two TCMB3– ligands adopt heptadentate coordination modes III and IV (Scheme 2). In mode III, a bidentate bridging carboxylic group (O17, O10c) to link Zn3 and
(b)
Zn1c. Ether O14 atom binds to Zn3 to form a five-membered chelating ring. Similarly, another bidentate bridging carboxylic group (O7, O24) links Zn2 and Zn4c, and ther O12 atom coordinates to Zn2, forming a five-membered chelating ring. A monodentate carboxylic group binds to Zn1 by O9 atom. In mode IV, a bidentate bridging carboxylic group (O19, O20) links Zn3 and Zn4. A carboxylic group (O15, O16) chelates to Zn3, while ether
(c)
O1 atom coordinated weakly to Zn4. A monodentate carboxylic group (O4, O5) coordinates to Zn2 via O5 atom, together with ether O3 atom binding to Zn2, forming a five-membered chelating ring. Moreover, the μ2-OH– ligand (O8) links Zn1 and Zn2 with a Zn1···Zn2 distance of
Figure 4. (a) Coordination structure of 4. (b) 1D [Zn2(TCMB)(μ3-OH)]n ribbon (up), and 2D doublelayered network (down). (c) Parallel packing diagram.
3.5002(8) Å. Finally, two distinct TCMB3– ligands and the ACS Paragon Plus Environment
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Crystal Growth & Design TCMB3− is pentadentate and adopts coordination mode
and 86.0° with the central phenyl ring. Each TCMB3−
V (Scheme 2), which possesses a monodentate carboxylic
combines five Cd(II) ions to afford a wave-like 2D
group and two bidentate bridging η1η1-μ2-carboxylic groups.
double-layered [Cd2(TCMB)]n network (Figure 5b). The
Every TCMB3− ligand combines five zinc ions. Three
pdta− anion is a planar tridentate ligand, which links Cd1
carbethoxyl groups twist 59.8°, 62.7° and 63.7° with the
and Cd2 via the tetrazolyl group to form a Cd2 dimer with a
central phenyl ring. The μ3-hydroxyl group connects three
Cd1···Cd2 distance of 3.987(1) Å (Figure 5b). Its pyridyl
zinc ions, and the Zn1−O3, Zn1A−O3 and Zn2−O3 bond
group further links Cd2 ion in adjacent [Cd2(TCMB)]n
distances
Å,
network. Therefore, the 2D double-layered [Cd2(TCMB)]n
respectively. A pair of Zn1/Zn1A and a pair of Zn2/Zn2A
networks are parallel arranged and further linked by pdta−
are connected by two μ3-hydroxyl groups and four
to construct a 3D coordination polymer (Figure 5c).
are
2.023(3),
2.216(3)
and
1.944(3)
bidentate bridging carboxylic groups to form a tetranuclear [Zn4(μ2-COO)4(μ3-OH)2]
cluster
with
a
Zn1···Zn1A
distance of 3.14(2) Å. The tetranuclear cluster as a secondary building unit (SBU) is further linked by
(a)
TCMB3−
spacer to afford a 1D [Zn2(TCMB)(μ3-OH)]n ribbon. These identical ribbons are parallel arranged and pillared by bidentate 4-abpt linker to generate a 2D double-layered coordination polymer (Figure 4b). The double-layered networks are parallel packed, as depicted in Figure 4c. [Cd2(TCMB)(pdta)(EtOH)(H2O)]n·2nH2O
(5).
Complex 5 is a 3D coordination polymer. The asymmetric
(b)
unit contains two independent Cd(II) ions, a TCMB3− and a pdta− ligands, an ethanol and a water ligands, and two lattice water molecules. Cd1 is octahedrally coordinated by three carboxylic oxygens, ethanol O9, water O7 and tetrazolyl N3 atoms (Figure 5a). Cd2 adopts a pentagonbipyramidal
geometry,
seven-coordinated
by
four
carboxylic oxygens, ether O4, pyridyl N5 and tetrazolyl N1 atoms. The apical positions are occupied by N5 and O5
(c)
atoms with a N5–Cd2–O5 bond angle of 173.6(1)°. Cd–O bond distances vary from 2.191(3) to 2.460(2) Å, except a weak ether oxygen coordination bond (Cd2–O4: 2.715(3) Å). Three Cd–N distances are in the 2.284(3)–2.337(3) Å
Figure 5. (a) Coordination structure of 5. (b) Wave-like 2D [Cd2(TCMB)]n network (up), and Cd-pdta zigzag chain (down). (c) 3D framework of 5.
range. TCMB3− is heptadentate and adopts coordination mode VI (Scheme 2). A carboxylic group chelates to Cd2A. A chelating-bridging η1η2-μ2-carboxylic group chelates to Cd1 and bridges Cd2 via O5 atom. A bidentate bridging η1η1-μ2-carboxylic group links Cd1B and Cd2B, while ether O4A atom binds to Cd2B, forming a five-membered chelating ring. Three carbethoxyl groups twist 52.0°, 61.1°
[Co3(TCMB)2(bpee)3(MeOH)(H2O)5]n (6). Complex 6 is a 3D coordination polymer. The asymmetric unit contains three independent Co(II) ions, two TCMB3– ligands, three bpee ligands, a methanol ligand and five coordinated water molecules. As shown in Figure 6a, Co1 adopts a cis-octahedral geometry completed by two carboxylic oxygens, two pyridyl nitrogens, and two water
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Page 8 of 21
oxygens (O1, O2). N1–Co1–N2 bond angle is 91.1(1)º.
(Figure 6b). Three distinct bpee ligands are bidentate and
Similarly, Co2 adopts a cis-octahedral geometry completed
connect Co(II) ions via their pyridyl terminals to form a 1D
by two carboxylic oxygens, two pyridyl nitrogens, and two
[Co3(bpee)3]n zigzag chain. The cross-linking of the 1D
water oxygens (O10, O11) with a N3–Co2–N4 bond angle
[Co3(bpee)3]n chain and 1D [Co3(TCMB)2]n ribbon
of 92.2(1)º. Co3 locates at the center of a trans-octahedral
facilitates the extension of 6 to a 3D framework, in which
geometry, coordinated by two carboxylic oxygens, two
the coordinated methanol and water molecules bind to
pyridyl nitrogens, water O21 and methanol O22 atoms.
Co(II) ions (Figure 6c). Previously, a 1D ladder-like
N5–Co3–N6 bond angle is 179.1(2)º. All the Co–O bond
{[Cd2(HTCMB)2(bpee)(H2O)4]·bpee·2H2O}n complex was
distances vary from 2.056(4) to 2.214(2) Å. Co–N
constructed, which was extended to a 2D supramolecular
distances are in the 2.083(3)–2.198(4) Å range.
network via bpee guest connector.44 [Co4(TCMB)2(bpee)2(μ3-OH)2(H2O)2]n·12nH2O
(7).
Complex 7 is a 3D porous coordination polymer. The
(a)
asymmetric unit consists of four independent Co(II) ions, two TCMB3– ligands, two bpee ligands, two μ3-OH− ligands, two coordinated water and twelve lattice water molecules. As shown in Figure 7a, all the Co(II) ions adopt distorted octahedral geometry, coordinated by a nitrogen atom and five oxygen atoms. Taking Co1 for instance, the equatorial plane is completed by two μ3-hydroxyl oxygens (O7, O9), carboxylic O1 and pyridyl N1 atoms. N1–Co1–O7 and O1–Co1–O9 bond angles are 175.2(1)º
(b)
and 177.5(1)º, respectively. The axial positions are occupied by carboxylic O4 and O5 atoms with a O4–Co1–O5 bond angle of 172.2(1)º. Co2 is coordinated by three carboxylic oxygens (O8, O10, O13), hydroxyl O9, pyridyl N2 and water O12W atoms. Co3 is similar to Co2, coordinated by hydroxyl O7 and water O15W atoms. Co4 is similar to Co1, combined with two hydroxyl groups (O7, O9). All the Co–O bond distances vary from 2.000(3) to
(c)
2.315(3) Å. Four Co–N distances vary from 2.093(4) to 2.139(4) Å. (a) Figure 6. (a) Coordination structure of 6. (b) 1D [Co3(TCMB)2]n ribbon (up), and 1D [Co3(bpee)3]n zigzag chain (down). (c) Perspective diagram of 3D framework. Two
TCMB3–
anions
are
tridentate
and
adopt
coordination mode VII (Scheme 2). Each TCMB3– ligand combines with three Co(II) ions via three monodentate carboxylic groups to form a 1D [Co3(TCMB)2]n ribbon ACS Paragon Plus Environment
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Crystal Growth & Design molecules are incorporated into the channels as guest molecules. [Co4(TCMB)2(bpee)2(μ3-OH)2(H2O)2]n·12nH2O
(b)
(8).
Complex 8 is a 3D coordination polymer. It is an isomer of 7 with obviously different unit cell dimensions and coordination structure. Complex 8 has a tetranuclear cobalt cluster [Co4(μ2-COO)6(μ3-OH)2] as SBU (Figure 8a), which is different from the [Co4(μ2-COO)3(μ3-COO)2(μ3-OH)2] in 7. Co2 is cis-octahedrally coordinated by two nitrogens and four oxygens, while Co4 is coordinated by six oxygens without nitrogen atom. However, every cobalt ion in 7 is coordinated by a nitrogen atom and five oxygen atoms. In 8,
(c)
Co1 and Co3 are both coordinated by a hydroxyl group, a pyridyl group, three carboxylic groups and a water molecule. Figure 7. (a) Coordination structure of 7, and tetranuclear cobalt cluster. (b) 2D [Co4(TCMB)2(μ3-OH)2]n network. (c) 3D framework.
All the Co–O bond distances (2.023(3)–2.229(3) Å) and Co–N bond distances (2.117(3)–2.167(3) Å) are normal as expected.
One TCMB3– is hexadentate and adopts coordination mode I. Two bidentate syn-syn η1η1-μ2-carboxylic groups
(a)
link Co1/Co3 and Co1/Co4. One η1η2-μ3-carboxylic group links Co1/Co2 by O4/O8 atoms and binds to Co3 via O4 atom. Another TCMB3– is tetradentate and adopts mode VIII (Scheme 2). One bidentate syn-syn η1η1-μ2-carboxylic group (O10, O11) links Co2/Co4. Another η1η2-μ3carboxylic group links Co3/Co4 and binds to Co2 via O13 atom. The third carboxylic group is uncoordinated. Besides, one μ3-OH− connects Co1, Co2 and Co4 via O9 atom, while another μ3-OH− connects Co1, Co3 and Co4 via O7 atom. Four Co(II) ions are connected by five carboxylic groups and two μ3-hydroxyl groups to afford a tetranuclear cobalt cluster [Co4(μ2-COO)3(μ3-COO)2(μ3-OH)2] (Figure 7a). Each tetranuclear cluster as a secondary building unit (SBU) is further linked to five adjacent ones by five TCMB3– spacers, affording a 2D [Co4(TCMB)2(μ3-OH)2]n network (Figure 7b). Two bidentate bpee ligands link the tetranuclear double-chain
cobalt
clusters
(Figure
S2).
to The
form
a
1D
cluster-based
linear 2D
[Co4(TCMB)2(μ3-OH)2]n networks are parallel arranged
(b)
(c)
Figure 8. (a) Coordination structure of 8, and tetranuclear cluster [Co4(μ2-COO)6(μ3-OH)2]. (b) Cluster-based 3D [Co4(TCMB)2(μ3-OH)2]n framework. (c) 3D porous MOF.
and pillared by bpee spacer to construct a 3D porous
Two TCMB3– anions are pentadentate and adopt
coordination polymer (Figure 7c). Twelve lattice water
coordination mode IX (Scheme 2). Each TCMB3– connects six
Co(II)
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ions
through
two
bidentate
bridging
Crystal Growth & Design 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
η1η1-μ2-carboxylic groups and a monodentate bridging
Scheme 2. Nine Coordination Modes of TCMB3– in 1–8
η0η2-μ2-carboxylic group via O17 or O19 atom to afford a cluster-based (Figure
8b),
3D
[Co4(TCMB)2(μ3-OH)2]n which
differs
M O
the
2D
[Co4(TCMB)2(μ3-OH)2]n network in 7. Two bidentate bpee
M
O M
O
O
I
O
bpee in a methanol-water solvent at slightly different temperature (85, 100 and 120 °C). Their structures are obviously different. Complexes 7 and 8 are two porous MOFs containing different tetranuclear cobalt clusters as SBUs, respectively, the total accessible volumes per unit cell volume are 28.1% and 38.1% calculated by PLATON,46 while the accessible volume of 6 is only 5.1%. Synthesis and Infrared Spectra. Complexes 1–8 were prepared by the hydrothermal reactions of metal acetates with H3TCMB and pyridyl-based ligands 4-abpt/Hpdta/bpee at 85–120 °C. The EtOH–H2O solvent was used in the preparations of 1–5, while MeOH–H2O solvent was used for 6–8. The molar ratios of metal acetates with H3TCMB and N-heterocycles were kept in 4:1:1 for 1–3, in 4:1:2 for 4–5, and in 6:1:2 for 6–8. Complexes 4–8 possess N-heterocyclic auxiliary ligands, whereas 4-abpt only plays an organic base in the preparation of 1–3. Comparing with the preparation of 3D zinc framework of 3, the molar amount of 4-abpt in preparing 4 was increased by double. We harvested a different 2D zinc network of 4, which has 4-abpt auxiliary ligand. In complexes 1–8, H3TCMB is fully deprotonated. Flexible TCMB3– exhibits nine coordination modes, as depicted in Scheme 2. Ether oxygen atoms take part in coordination in modes III, IV and VI, corresponding to complexes 3 and 5. In previously reported nine H3TCMB complexes, only [Cu3(TCMB)2py3(H2O)3·10H2O] complex displays ether oxygen-coordination.42
M
M
O M
M
O
O O
O
O
O
O
O
M
M
M
O
M O
M O
O
O
M
O
III
II
O
M O
M O
O
M O O
O
O M
M O
O
O O
M
M
M
O M
O
O
O
O
O
M O
O
M
O
O
O O M
V O
M
O
O
O
M
O
VII
M
O M
O
O O
M
O
O
M
M O
M
O O
O O
VIII
M O
O
VI
O
O
M
O
O
IV
incorporated into the channels as guest molecules. by the reactions of Co(OAc)2·4H2O with H3TCMB and
M O
O
O
(Figure 8c), where twelve lattice water molecules are Above-mentioned cobalt complexes 6–8 were prepared
M O
M
form a 1D zigzag double-chain (Figure S3), which is structure of 8 is a 3D porous metal-organic framework
M O O
O
ligands link tetranuclear [Co4(COO)6(μ3-OH)2] clusters to different from the 1D linear double-chain in 7. The final
M O
M O
framework
from
Page 10 of 21
M
M M
O M
O
O
O
O
O
IX
M
M
IR spectra of 1−8 exhibit characteristic bands of TCMB3– and N-heterocyclic ligands (Figure S4). Their asymmetric and symmetric stretching vibrations of carboxylic groups appear at about 1597 and 1409 cm–1, respectively. The absence of –COOH characteristic peak near 1700 cm–1 indicates H3TCMB fully deprotonated. Complex 4 shows the N–H stretching vibration of 4-abpt at 3319 cm–1. Complex 5 lacks the N–H characteristic peak near 3300 cm–1, indicates the tetrazolyl of Hpdta deprotonated. Cu(II) complex 2 displays a sharp μ3-O–H stretching vibration band at 3543 cm−1. The bands near 3082, 2890, 1262, 1037, and 781 cm−1 are respectively assigned to ν(Ar−H), ν(−CH2−), ν(C−O), ν(C−C), and γ(Ar−H) vibrations. The C–H out-of-plane bending vibration of pyridyl group appears at about 810 cm−1. Broad band near 3450 cm–1 is assigned to the O–H stretching vibrations of coordinated and/or lattice water. Hydrolysis Controlled Synthesis Strategy and PXRD Study. Generally, deprotonation procedure is important in preparing carboxylic complexes.47 It is noteworthy that Cu(II) complex 2, Zn(II) complex 4, and Co(II) complexes 7 and 8 contain μ3-hydroxyl group, while Zn(II) complex 3 has a μ2-hydroxyl group. This phenomenon indicates partial hydrolysis happened. It is well-known that divalent transition-metal ions are easy hydrolyzed in a neutral aqueous solution. Comparing the precipitation-dissolution equilibrium constants of MII(OH)2 compounds, the Ksp values of Mn2+ (2×10-13) and Cd2+ (7×10-15) are close to the
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Crystal Growth & Design
value of Co2+ (6×10-15) and remarkably larger than those of Zn2+
(3×10-17)
and
Cu2+
(2×10-20).
Therefore, Cu(2) and
From above experimental results, we have guessed a hydrolysis
reaction
mechanism
(Scheme
3).
With
Zn(3,4) complexes occur partially hydrolysis, whereas
hydrothermal temperature increased, the differences of
Mn(1) and Cd(5) complexes have not hydrolyzed.
Co(II) hydrolysis and coordination resulted in the structural
Previously, four 2D and 3D Cd(II)-TCMB complexes were
diversity of 6–8. Under 85 °C, complex 6 did not hydrolyze
prepared under similar hydrothermal conditions without
and
hydrolysis happened.43 Perhaps Co2+ (Ksp = 6×10-15) locates
[Co3(TCMB)2]n ribbon. When temperature increased to 100
at the critical point of hydrolysis, cobalt complexes 7 and 8
°C, hydrolysis happened. Four Co(II) ions are connected by
happen hydrolysis, whereas cobalt complex 6 does not
two μ3-hydroxyl groups and five carboxylic groups to
hydrolyze. Based on Ksp values of metal hydroxides, the
afford
hydrolysis controlled synthesis strategy is helpful in the
[Co4(μ2-COO)3(μ3-COO)2(μ3-OH)2]. A carboxylic group is
designed synthesis of hydroxyl-containing coordination
uncoordinated. It seems to indicate that the structure of 7 is
polymers and metal-hydroxyl clusters.
an unstable transition state. The tetranuclear clusters are
had
three
a
distinct
isolated
tetranuclear
Co(II)
cobalt
ions
in
cluster
What is interesting is that the cobalt 3D frameworks
linked to form a 2D [Co4(TCMB)2(μ3-OH)2]n network. By
6–8 were prepared under similar reaction conditions with
increased temperature to 120 °C, the unstable tetranuclear
slightly different temperature, respectively at 85, 100 and
cluster was further converted to a more symmetric and
120 °C. Their 3D structures are much different. Complex 6
stable tetranuclear cluster [Co4(μ2-COO)6(μ3-OH)2], here
has no hydroxyl group. Co(II) ions are isolated by large
the six carboxylic groups of two TCMB3– ligands in 8 all
tridentate TCMB3– ligand, while bpee ligands link Co1,
take part in coordination. The 2D [Co4(TCMB)2(μ3-OH)2]n
Co2 and Co3 to form a 1D zigzag chain. Complexes 7 and
network in 7 was also changed to a 3D porous framework
8 have similar formulas, but obvious differences in their 3D
in 8. Previously, Li and coworker have prepared several
frameworks. Complex 7 possesses a hexadentate (mode-I)
MOFs based on metal-hydroxyl tetranuclear clusters.48–50
and a tetradentate (mode-VIII) TCMB3– ligands. One carboxylic
group
in
the
tetradentate
TCMB3–
is
uncoordinated. Two bpee ligands link Co1/Co2 and Co3/Co4 to form two binuclear Co2(bpee) pieces (Figure S2). Two TCMB3– ligands in 8 adopt pentadentate mode (IX). The bpee ligands link Co1, Co2 and Co3 to form a trinuclear Co3(bpee)2 piece (Figure S3), whereas Co4 is coordinated by six oxygens without N-donor.
Scheme 3. Hydrolysis Procedure in Complexes 6–8
Figure 9. PXRD comparison of the products obtained by the hydrothermal reactions at different temperatures. To further explore the effect of the temperature on the preparations of 6–8, we have done a series of hydrothermal reactions from 60 to 140 °C, and obtained different products. As illustrated in Figure 9, the experimental ACS Paragon Plus Environment
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Page 12 of 21
PXRD results obtained at 60, 70 and 90 °C are pretty
Thermal Analyses. In order to investigate the thermal
consistent with the simulated pattern of 6 prepared at 85 °C.
stability of 1–8, their thermal analyses (TG-DSC) were
With the increase of temperature, at 100 °C, four new
completed in 20−800 ºC range. The results are shown in
diffraction peaks were discovered below 10º, which
Figure 10 and Figure S7. Complex 1 lost four lattice water
indicate the formation of a new crystal product that is
and four coordinated water molecules in 50−230 °C (obsd
complex 7. At 120 °C, complex 8 was obtained. The
15.6%, calcd 15.9%). Dehydrated compound successively
diffraction peaks were disappeared at 8.56º, 9.72º and
decomposed after 400 °C. Complex 2 lost half lattice water
17.58º, while a new diffraction peak was discovered at
in 50–130 ºC (obsd 1.2%, calcd 1.6%). Dehydrated
7.08º. The product obtained at 110 °C may be a mixture of
compound was stable to 240 °C, and then decomposed
7 and 8. Upon heating to 130 °C, two new diffraction peaks
quickly. Complex 3 lost two lattice water and four
were discovered at 6.36º and 36.7º, and the diffraction
coordinated water molecules in 130−220 °C (obsd 11.8%,
peaks obviously widen, suggesting the low degree of
calcd 11.4%). Dehydrated compound was stable to 330 °C,
crystallization of the product. At 140 °C, a sharp reduction
and then successively decomposed to 800 °C without
of the diffraction peak number was observed in the PXRD
stopping. Complex 4 lost 5.8% weight in 120−300 °C,
pattern, as a consequence of crystal structure collapse or
corresponding to release a lattice water and hydroxyl group
completely hydrolyzed Co(OH)2 powder product formed.
(calcd 5.0%). The intermediate successively decomposed to
These remarkable variations of the PXRD results distinctly
800 °C without stopping. Complex 5 lost two lattice water
indicate the occurrence of crystal complex conversions.
molecules, and a water and an ethanol ligands in 30−170
As we all know, temperature has great influence on hydrolytic reaction. Comparing the complexes 6, 7 and 8,
°C (obsd 9.6%, calcd 13.0%). The intermediate was stable to 300 °C and then successively decomposed.
we find that 6 synthesized at 85 °C has no hydroxyl group. but 7 synthesized at 100 °C has two μ3-hydroxyl groups, and 8 synthesized at 120 °C has two μ3-hydroxyl groups, which is compatible with the above-mentioned PXRD analysis. In consideration of the similar formulas of 7 and 8, we collected the crystals of 7 and mixed them with methanol (4 mL) and water (4 mL). Then the mixture was sealed in a Teflon-lined reactor and heated at 120 °C for three days. From the PXRD pattern of resulting product, it is evident that partial complex 7 has transformed to 8 (Figure S5). This crystal-to-crystal transition procedure indicates that 8 is a more stable complex.
Co(II) complex 6 lost 9.8% weight in 50−140 °C,
Besides, the PXRD patterns of 1–8 have been measured to check their phase purity in the synthesized products. The peak positions of measured PXRD patterns match well with the simulated ones (Figure S6), indicating the crystal structures are truly representatives of the bulk crystalline products. The differences in the peak intensities of 1, 3 and 5 may be owing to the preferred orientation of these sheet crystal samples.
Figure 10. TG curves of complexes 1−8.
corresponding to the removal of a methanol and five water ligands (calcd 8.5%). The intermediate was stable to 260 °C and then successively decomposed. Complex 7 lost 16.5% weight in 40−150 °C, indicating the release of twelve lattice water molecules and two water ligands (calcd 17.0%). Dehydrated compound kept stable to 300 °C and then successively decomposed. Similarly, complex 8 lost 12.2% weight in 20−170 °C, indicating the removal of twelve lattice water molecules and two water ligands (calcd
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Crystal Growth & Design
17.0%). Comparing the TG curves of 7 and 8 (Figure S7),
η1η1-μ2-carboxylic group can mediate antiferromagnetic
lattice water in 7 is stable to 40 °C, whereas lattice water in
interaction,30 which dominants the magnetic coupling of
8 is slightly unstable, maybe released before 20 °C. The
complex 1. The η1η2-μ3-carboxylic group links Mn2 and
dehydrated compound of 8 kept stable to 310 °C and then
Mn2B via O5−C1B−O3B carboxylic bridge that favors
successively decomposed. Thermal analyses demonstrate
antiferromagnetic interaction. O5-bridging atom links Mn2
the dehydrated compounds of 3, 4, 5, 7 and 8 kept higher
and Mn2A with a Mn2−O5−Mn2A bond angle of
thermal stability to 300 oC.
105.8(1)º.
Magnetic Properties. In the design of molecule-based
Cu(II) complex 2 is an interesting 2D sandwich-like
magnetic materials, the most important factor concerns the
coordination polymer, in which [Cu3(μ3-OH)3]n layer is
connectors between paramagnetic ions. Shorter connector
sandwiched between two organic layers originating from
often brings to stronger magnetic coupling. Magnetic
typical tripodal TCMB3− ligands. Therefore, the magnetic
interactions of transition metal complexes tend to decrease
interaction is limited in the [Cu3(μ3-OH)3]n layer, whereas
in the order: metal oxide/hydroxide > metal cyanide >metal
interaction between layers can be neglected. The χMT value
N-heterocycle.51
Hydroxyl group as a
of complex 2 at 300 K is 1.30 emu K mol−1, which is
monoatomic bridge and carboxylic group as a triatomic
slightly higher than the only-spin value of three isolated
bridge
exchange
Cu(II) ions (1.13 emu K mol−1 with g = 2.0 and S = 1/2).
carboxylic
Upon cooling, the χMT value steadily increases to a
carboxylate > metal can
interaction.
effectively
transmit
Metal-hydroxyl
magnetic
clusters
complexes often exhibit varied magnetic
and
In
maximum of 1.75 emu K mol−1 at 35 K. This phenomenon
this work, complexes 1, 2, 7 and 8 have hydroxyl and
indicates the ferromagnetic coupling between Cu(II) ions
carboxylic groups connected paramagnetic polynuclear
dominates the magnetic properties of complex 2. The
metal
magnetic
inverse magnetic susceptibility curve shows a linear
susceptibilities were measured in the temperature range of
behavior in the 50−300 K range and obeys the
2−300 K. The magnetic data are depicted in Figure 11, as
Curie−Weiss law with C = 1.29 emu K mol−1 and θ = 20.68
the plots of χMT and χM−1 versus T.
K. The positive θ value indicates a ferromagnetic coupling
clusters.
Their
properties.52–54
variable-temperature
For Mn(II) complex 1, the χMT value at 300 K is 12.34
in the [Cu3(μ3-OH)3]n layer. For Cu(II)-hydroxide complex,
emu K mol−1, which is close to the only-spin value of three
it is well-known that ferromagnetic interaction could be
isolated Mn(II) ions (13.14 emu K
mol−1
with g = 2.0 and S
contributed by a smaller Cu–O(H)–Cu bridging angle.56 In
= 5/2). Upon cooling, the χMT value keeps almost a
the [Cu3(μ3-OH)3]n layer, three Cu–O(H)–Cu bond angles
constant value until 88 K, and then decreases in a
around the central hydroxyl O2 atom (Cu1A–O2–Cu1B,
continuous fashion and finally reaches 1.05 emu K
at
Cu1A–O2–Cu1 and Cu1–O2–Cu1B) are 96.8(2)º, 113.7(2)º
2 K. It indicates an antiferromagnetic coupling between
and 126.5(2)º, respectively. The Cu1…Cu1A, Cu1…Cu1B
Mn(II) ions. In the range of 38−45 K, the shake of χMT−T
and Cu1A … Cu1B distances are 3.241(1), 3.747(2) and
curve originates from the trace impurity of manganese
3.156(2) Å, respectively. It is noticed that the dx2−y2
oxides such as ferromagnetic Mn3O4.55 The inverse
magnetic orbital of Cu1 lies on the basal plane (O1A, O2,
magnetic susceptibility curve shows a linear behavior in
O2B and O3) of a square-pyramidal geometry, while the
20−300 K and obeys the Curie−Weiss law χM = C/(T−θ),
dx2−y2 magnetic orbital of Cu1A lies on the basal plane (O1,
yielding C = 12.54 emu K mol−1 and θ = −5.9 K. The
O2, O2C and O3A). Both dx2−y2 magnetic orbitals tend to
negative θ value suggests a weak antiferromagnetic
orthogonality with a dihedral angle of 61.4(1)° (Figure S8).
interaction. In complex 1, the hexadentate
mol−1
ligand
Similarly, the dx2−y2 magnetic orbital of Cu1B lies on the
groups and a
basal plane (O1B, O2D, O2E and O3B), which has a
η1η2-μ3-carboxylic group (mode I). Generally, syn-syn
61.4(1)° dihedral angle with that of Cu1, and parallel to the
possesses two syn-syn
η1η1-μ2-carboxylic
TCMB3−
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Page 14 of 21
magnetic orbital of Cu1A with a 2.234 Å distance between planes. Above-mentioned small Cu–O(H)–Cu angle and magnetic
orbital
orthogonality
can
result
in
the
ferromagnetic coupling in complex 2.29 Besides, the decline of χMT below 35 K could be due to antiferromagnetic interaction transmitted by three syn–syn η1η1-μ2-carboxylic groups of TCMB3− ligand (Figure 2b).
[Co4(TCMB)2(bpee)2(μ3-OH)2(H2O)2]n·12nH2O (8) Figure 11. Plots of χMT and χM−1 vs T for 1, 2, 7 and 8. Complexes 7 and 8 are two 3D MOFs, which possess different tetranuclear Co(II) clusters. For complex 7, the χMT value at 300 K is 11.1 emu K mol−1, which is obviously higher than the only-spin value of four isolated [Mn3(TCMB)2(H2O)4]n·4nH2O (1)
Co(II) ions (7.50 emu K mol−1 with S = 3/2, assuming g = 2.0). This is due to the large orbital contribution of Co(II) ion located in an octahedral geometry.51 Upon cooling, the χMT value decreases gradually to a minimum of 0.87 emu K mol−1 at 2 K. This behavior is consistent with dominant antiferromagnetic interaction. The data above 27 K can be fitted to the Curie−Weiss law with C = 13.22 emu K mol−1 and θ = −51.98 K. In complex 7, two distinct TCMB3– ligands adopt coordination mode-I (like Mn complex 1) and mode-VIII. It is easy to transmit antiferromagnetic coupling.
[Cu3(TCMB)(μ3-OH)3]n·0.5nH2O (2)
Three
Co–O(H)–Co
bond
angles
around
μ3-hydroxyl O7 atom (Co1–O7–Co4, Co1–O7–Co3 and Co3–O7–Co4) are 93.5(1)º, 101.4(2)º and 127.9(2)º. The Co1 … Co4, Co1 … Co3 and Co3 … Co4 distances are 3.041(1), 3.175(1) and 3.660(1) Å. The Co–O(H)–Co bond angles and Co…Co distances around μ3-hydroxyl O9 atom are similar. Unlike Cu(II) complex 2, smaller Co–O(H)–Co bond angles do not bring obvious ferromagnetic coupling. For Co(II) complex 8, the χMT value at 300 K is 12.69 emu K mol−1, which is higher than the only-spin value of four isolated Co(II) ions (7.50 emu K mol−1). Upon cooling, the χMT value decreases gradually to 5.19 emu K mol−1 at 13 K, then increases sharply to 7.49 emu K mol−1 at 7 K,
[Co4(TCMB)2(bpee)2(μ3-OH)2(H2O)2]n·12nH2O (7) ACS Paragon Plus Environment
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Crystal Growth & Design
finally decreases to 3.04 emu K mol−1 at 2 K. From the
enough and overcomes the effect of orbital contribution,
viewpoint of magnetic coupling, this behavior is consistent
leading to the increase of χMT value at 7 K.
with dominant antiferromagnetic interaction in complex 8, accompanied by a weak ferromagnetic coupling at low temperature. The data above 27 K is fitted to the Curie−Weiss law, yielding C = 14.19 emu K mol−1 and θ = −39.99 K. In complex 8, two TCMB3– ligands adopt coordination mode-IX. Each TCMB3– has two bidentate syn-syn η1η1-μ2-carboxylic groups and a monodentate bridging η0η2-μ2-carboxylic group, forming a more symmetric tetranuclear cluster [Co4(TCMB)2(μ3-OH)2]n. The syn-syn η1η1-μ2-carboxylic groups can transmit antiferromagnetic bridging
interaction,
η0η2-μ2-carboxylic
whereas group
monodentate can
mediate
ferromagnetic interaction.30 Three Co–O(H)–Co angles around
μ3-hydroxyl
O16
atom
(Co2–O16–Co4,
Co1–O16–Co4 and Co1–O16–Co2) are 99.0(1)º, 100.0(1)º and 123.1(1)º. The Co2…Co4, Co1…Co4 and Co1…Co2 distances are 3.181(1), 3.150(1) and 3.645(2) Å. The Co–O(H)–Co bond angles and Co … Co distances around μ3-hydroxyl O15 atom are similar. In complex 8, smaller Co–O(H)–Co bond angles and the monodentate bridging η0η2-μ2-carboxylic groups bring a weak ferromagnetic coupling at very low temperature. However, it is difficult to theoretically analyze the magnetic susceptibility data of Co(II) complexes,57,58 because there are strong spin−orbit coupling and highly magnetic anisotropy in Co(II) ion. Vilminot and Kurmoo point out,51 Co(II) is a Kramer’s ion with a considerable spin-orbit coupling. The effective spin is 3/2 at room temperature and could be reduced to 1/2 at low temperature. This effective spin reduction would relate a virtual Weiss constant (θ) of ca. −20 K for one isolated Co(II) ion. This phenomenon can bring out quite complexity to the magnetic properties of Co(II) complexes. If analyzing magnetic property according to the viewpoint of Vilminot and Kurmoo,51 upon cooling, the decrease of χMT value could originate from the spin−orbit coupling of Co(II) ions. There are two comparable interactions of ferromagnetic coupling and orbital contribution in complex 8. In low temperature range, the ferromagnetic coupling is strong
CONCLUSIONS Eight novel coordination polymers and metal-organic frameworks were assembled by a tripodal ether-linked tricarboxylic acid. The tricarboxylate ligand exhibits nine types of coordination modes. These complexes display structural variation with interesting 2D and 3D networks. The results demonstrate that the ether-linked tricarboxylic acid is a good flexible multidentate ligand in constructing coordination polymers. Five complexes contain μ3- and μ2-hydroxyl groups. A hydrolysis controlled synthesis strategy is suggested based on Ksp values of metal hydroxides. Temperature has great influence on the hydrolytic reactions of cobalt complexes 6–8. PXRD study reveals the hydrolysis mechanism. Four complexes present antiferromagnetic and/or ferromagnetic interactions. Their magneto-structural correlations are studied. ASSOCIATED CONTENT Supporting Information Supporting information is available free of charge on the ACS Publications website at DOI: XXXX Bond distances and angles, hydrogen bonds, structural figures, IR spectra, PXRD patterns, and thermal analyses (PDF). Accession Codes CCDC 1888154−1888161 contain the supplementary crystallographic data. These data can be obtained free of charge via www.ccdc.cam.ac.uk/data_request/cif, or by emailing
[email protected], or by contacting The Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax: +44 1223 336033. AUTHOR INFORMATION Corresponding Author *E-mail:
[email protected]. Tel: 86-21-66132803. ORCID Ming-Xing Li: 0000-0003-0000-9876
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Notes The authors declare no competing financial interest. ACKNOWLEDGMENTS This work was financially supported by Natural Science Foundation of Shanghai (17ZR1410600, 16ZR1411400) and National Natural Science Foundation of China (21171115). References (1) Kirchon, A.; Feng, L.; Drake, H. F.; Josepha, E. A.; Zhou, H.-C. From Fundamentals to Applications: A Toolbox for Robust and Multifunctional MOF Materials. Chem. Soc. Rev. 2018, 47, 8611–8638. (2) O’Keeffe, M.; Yaghi, O. M. Deconstructing the Crystal Structures of Metal-Organic Frameworks and Related Materials into Their Underlying Nets. Chem. Rev. 2012, 112, 675–702. (3) Lin, Z.-J.; Lü, J.; Hong, M.; Cao, R. Metal–Organic Frameworks Based on Flexible Ligands (FL-MOFs): Structures and Applications. Chem. Soc. Rev. 2014, 43, 5867−5895. (4) Batten, S. R.; Champness, N. R.; Chen, X.-M.; Garcia-Martinez, J.; Kitagawa, S.; Öhrström, L.; O’Keeffe, M.; Suh, M. P.; Reedijk, J. Coordination Polymers, Metal–Organic Frameworks and the Need for Terminology Guidelines. CrystEngComm 2012, 14, 3001−3004. (5) Silva, P.; Vilela, S. M. F.; Tomé, J. P. C.; Paz, F. A. A. Multifunctional Metal–Organic Frameworks: From Academia to Industrial Applications. Chem. Soc. Rev. 2015, 44, 6774−6803. (6) Li, M.; Li, D.; O’Keeffe, M.; Yaghi, O. M. Topological Analysis of Metal−Organic Frameworks with Polytopic Linkers and/or Multiple Building Units and the Minimal Transitivity Principle. Chem. Rev. 2014, 114, 1343−1370. (7) Stock, N.; Biswas, S. Synthesis of Metal-Organic Frameworks (MOFs): Routes to Various MOF Topologies, Morphologies, and Composites. Chem. Rev. 2012, 112, 933–969. (8) Espallargas, G. M.; Coronado, E. Magnetic Functionalities in MOFs: from the Framework to the Pore. Chem. Soc. Rev. 2018, 47, 533−557. (9) Lustig, W. P.; Li, J. Luminescent Metal–Organic Frameworks and Coordination Polymers as Alternative Phosphors for Energy Efficient Lighting Devices. Coord. Chem. Rev. 2018, 373, 116–147. (10) Burtch, N. C.; Walton, K. S. Modulating Adsorption and Stability Properties in Pillared Metal−Organic Frameworks: A Model System for Understanding Ligand Effects. Acc. Chem. Res. 2015, 48, 2850−2857. (11) Shi, P.-P.; Tang, Y.-Y.; Li, P.-F. Liao, W.-Q.; Wang, Z.-X.; Ye, Q.; Xiong, R.-G. Symmetry Breaking in Molecular Ferroelectrics. Chem. Soc. Rev. 2016, 45, 3811–3827. (12) Qin, L.; Zheng, H.-G. Structures and Applications of Metal–Organic Frameworks Featuring Metal Clusters.
Page 16 of 21
CrystEngComm 2017, 19, 745–757. (13) Guo, Z.; Cao, R.; Wang, X.; Li, H.; Yuan, W.; Wang, G.; Wu, H.; Li, J. A Multifunctional 3D Ferroelectric and NLO-Active Porous Metal-Organic Framework. J. Am. Chem. Soc. 2009, 131, 6894–6895. (14) Du, M.; Li, C.-P.; Liu, C.-S.; Fang, S.-M. Design and Construction of Coordination Polymers with Mixed-Ligand Synthetic Strategy. Coord. Chem. Rev. 2013, 257, 1282−1305. (15) Jiang, H.-L.; Makal, T. A.; Zhou, H.-C. Interpenetration Control in Metal–Organic Frameworks for Functional Applications. Coord. Chem. Rev. 2013, 257, 2232–2249. (16) Li, C.-P.; Du, M. Role of Solvents in Coordination Supramolecular Systems. Chem. Commun. 2011, 47, 5958–5972. (17) Long, L.-S. pH Effect on the Assembly of Metal–Organic Architectures. CrystEngComm 2010, 12, 1354–1365. (18) Li, M.-X.; Wang, X.-Q.; Wang, Z.-X.; Shao, M.; He, X. Temperature and Solvent Controlled Syntheses of Six Hydrous 5-(3-Pyridylmethoxy)isophthalate Cd(II) Coordination Polymers. Inorg. Chim. Acta 2017, 467, 316–324. (19) Paz, F. A. A.; Klinowski, J.; Vilela, S. M. F.; Tomé, J. P. C.; Cavaleiroc, J. A. S.; Rocha, J. Ligand Design for Functional Metal–Organic Frameworks. Chem. Soc. Rev. 2012, 41, 1088–1110. (20) Lu, W.; Wei, Z.; Gu, Z.-Y.; Liu, T. F.; Park, J.; Park, J.; Tian, J.; Zhang, M.; Zhang, Q.; Gentle, T.; Bosch, M.; Zhou, H.-C. Tuning the Structure and Function of Metal–Organic Frameworks via Linker Design. Chem. Soc. Rev. 2014, 43, 5561–5593. (21) Kitagawa, S.; Kitaura, R.; Noro, S. Functional Porous Coordination Polymers. Angew. Chem., Int. Ed. 2004, 43, 2334–2375. (22) Deng, D.; Liu, L.; Ji, B.-M.; Yin, G.; Du, C. Temperature, Cooling Rate, and Additive-Controlled Supramolecular Isomerism in Four Pb(II) Coordination Polymers with an in Situ Ligand Transformation Reaction. Cryst. Growth Des. 2012, 12, 5338–5348. (23) Wang, T.; Zhang, C.; Ju, Z.; Zheng, H. Solvent-Induced Synthesis of Cobalt(II) Coordination Polymers Based on a Rigid Ligand and Flexible Carboxylic Acid Ligands: Syntheses, Structures and Magnetic Properties. Dalton Trans. 2015, 44, 6926–6935. (24) Zhu, X.; Liu, X.-G.; Li, B.-L.; Zhang, Y. Solvent-Controlled Assembly of Supramolecular Isomers: 2D (4,4) Network, 1D Ribbons of Ring, and Both 2D (4,4) Networks and 1D Ribbons of Rings Polycatenated in a 3D Array. CrystEngComm 2009, 11, 997–1000. (25) Han, S.-D.; Zhao, J.-P.; Liu, S.-J.; Bu, X.-H. Hydro(solvo)thermal Synthetic Strategy Towards Azido/Formato-Mediated Molecular Magnetic Materials. Coord. Chem. Rev. 2015, 289–290, 32–48. (26) Zhang, L.; Liu, L.; Huang, C.; Han, X.; Guo, L.; Xu, H.; Hou, H.; Fan, Y. Polynuclear Ni(II)/Co(II)/Mn(II) Complexes Based on Terphenyl Tetracarboxylic Acid Ligand: Crystal Structures and Research of Magnetic Properties. Cryst. Growth Des. 2015, 15, 3426−3434. (27) Yang, P.; Wang, M.-S.; Shen, J.-J.; Li, M.-X.;
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Wang, Z.-X.; Shao, M.; He, X. Seven Novel Coordination Polymers Constructed by Rigid 4-(4-Carboxyphenyl)terpyridine Ligands: Synthesis, Structural Diversity, Luminescence and Magnetic Properties. Dalton Trans. 2014, 43, 1460–1470. (28) Yang, F.; Li, B.; Xu, W.; Li, G.; Zhou, Q.; Hua, J.; Shi, Z.; Feng, S. Two Metal−Organic Frameworks Constructed from One-Dimensional Cobalt(II) Ferrimagnetic Chains with Alternating Antiferromagnetic/ Ferromagnetic and AF/AF/FM Interaction: Synthesis, Structures, and Magnetic Properties. Inorg. Chem. 2012, 51, 6813−6820. (29) Li, M.-X.; Zhang, Y.-F.; He, X.; Shi, X.-M.; Wang, Y.-P.; Shao, M.; Wang, Z.-X. Diverse Structures and Ferro-/Ferri-/Antiferromagnetic Interactions of Pyridyltetrazole Coordination Polymers with Polycarboxylate Auxiliary Ligands. Cryst. Growth Des. 2016, 16, 2912−2922. (30) Zheng, Y.-Z.; Zheng, Z.-P.; Chen, X.-M. A Symbol Approach for Classification of Molecule-Based Magnetic Materials Exemplified by Coordination Polymers of Metal Carboxylates. Coord. Chem. Rev. 2014, 258–259, 1–15. (31) Liu, T.-F.; Liu, J.; Cao, R. Coordination Polymers Based on Flexible Ditopic Carboxylate or Nitrogen-Donor Ligands. CrystEngComm 2010, 12, 660–670. (32) Cao, L.-H.; Li, H.-Y.; Zang, S.-Q.; How, H.-W.; Mak, T. C. W. (4,4)-Connected Self-penetrating Pillared-Layered Metal−Organic Framework Based on a Nanosized Flexible Aromatic Carboxylic Acid Ligand. Cryst. Growth Des. 2012, 12, 4299−4301. (33) He, Y.; Li, B.; O’Keeffe, M.; Chen, B. Multifunctional Metal–Organic Frameworks Constructed from Meta-Benzenedicarboxylate Units. Chem. Soc. Rev. 2014, 43, 5618−5656. (34) Qiu, W.; Perman, J. A.; Wojtas, Ł.; Eddaoudi, M.; Zaworotko, M. J. Structural Diversity Through Ligand Flexibility: Two Novel Metal–Organic Nets via Ligand-to-Ligand Cross-Linking of ‘‘Paddlewheels’’. Chem. Commun. 2010, 46, 8734–8736. (35) Hu, J.-S.; Yao, X.-Q.; Zhang, M.-D.; Qin, L.; Li, Y.-Z.; Guo, Z.-J.; Zheng, H.-G.; Xue, Z.-L. Syntheses, Structures, and Characteristics of Four New Metal−Organic Frameworks Based on Flexible Tetrapyridines and Aromatic Polycarboxylate Acids. Cryst. Growth Des. 2012, 12, 3426–3435. (36) Wang, S.-L.; Hu, F.-L.; Zhou, J.-Y.; Zhou, Y.; Huang, Q.; Lang, J.-P. Rigidity versus Flexibility of Ligands in the Assembly of Entangled Coordination Polymers Based on Bi- and Tetra Carboxylates and N-Donor Ligands. Cryst. Growth Des. 2015, 15, 4087–4097. (37) Ma, T.; Li, M.-X.; Wang, Z.-X.; Zhang, J.-C.; Shao, M.; He, X. Structural Diversity, Luminescence, and Magnetic Properties of Eight Co(II)/Zn(II) Coordination Polymers Constructed from Semirigid Ether-Linked Tetracarboxylates and Bend Dipyridyl-Triazole Ligands. Cryst. Growth Des. 2014, 14, 4155–4165. (38) He, X.; Lu, X.-P.; Li, M.-X.; Morris, R. E. Tuning Different Kinds of Entangled Networks Formed by Isomers of Bis(1,2,4-triazol-1-ylmethyl)benzene and a Flexible Tetracarboxylate Ligand. Cryst. Growth Des. 2013, 13,
1649–1654. (39) He, X.; Lu, X.-P.; Ju, Z.-F.; Li, C.-J.; Zhang, Q.-K.; Li, M.-X. Syntheses, Structures, and Photoluminescent Properties of Ten Metal–Organic Frameworks Constructed by a Flexible Tetracarboxylate Ligand. CrystEngComm 2013, 15, 2731–2744. (40) Lu, J.; Zeng, Q.-D.; Wang, C.; Zheng, Q.-Y.; Wan, L.; Bai, C. Self-Assembled Two-Dimensional Hexagonal Networks. J. Mater. Chem. 2002, 12, 2856–2858. (41) Wu, G.; Wang, X.-F.; Kawaguchi, H.; Sun, W.-Y. Synthesis and Crystal Structure of Mn(II) and Zn(II) Complexes with 1,3,5-Tris(carboxymethoxyl) Benzene Ligand. J. Chem. Cryst. 2007, 37, 199–205. (42) Wang, S.-N.; Bai, J.; Li, Y.-Z.; Scheer, M.; You, X.-Z. Metal Disordering Cu(II) Supramolecular Polymers Constructed from a Tripodal Ligand Possessing Two Different Functional Groups. CrystEngComm 2007, 9, 228–235. (43) Wang, S.; Xing, H.; Li, Y.; Bai, J.; Pan, Y.; Scheer, M.; You, X. 2D and 3D Cd(II) Coordination Polymers from a Flexible Tripodal Ligand of 1,3,5-Tris(carboxymethoxy)benzene and Bidentate Pyridyl-Containing Ligands with Three-, Eight- and Ten-Connected Topologies. Eur. J. Inorg. Chem. 2006, 3041–3053. (44) Wang, S.-N.; Li, D.-C.; Dou, J.-M.; Wang, D.-Q. An Unusual Polycatenating Network Self-Assembled by the 2D 2D Parallel 3D Parallel Interpenetration of Coordinative and Hydrogen-Bonded (6,3) Motifs. Acta Cryst, C 2010, 66, m118–m121. (45) Sheldrick, G. M. SHELXTL Version 6.1; Bruker AXS Inc.: Madison, Wisconsin, USA, 2000. (46) Spek, A. L. PLATON, A Multipurpose Crystallographic Tool; Utrecht University: Utrecht, The Netherlands, 2002. (47) Shen, J.-J.; Li, M.-X.; Wang, Z.-X.; Duan, C.-Y.; Zhu, S.-R.; He, X. Unexpected 4-Fold [2+2] Interpenetration and Polycatenation Behaviors in Porous Luminescent Zinc Metal−Organic Frameworks Constructed from Flexible 3,5-Bis(4-pyridylmethoxy)benzoate Ligand. Cryst. Growth Des. 2014, 14, 2818−2830. (48) Lv, X.-X.; Shi, L.-L.; Li, K,; Li, B.-L.; Li, H.-Y. An Unusual Porous Cationic Metal–Organic Framework Based on a Tetranuclear Hydroxyl-Copper(II) Cluster for Fast and Highly Efficient Dichromate Trapping Through a Single-Crystal to Single-Crystal Process. Chem. Commun. 2017, 53, 1860−1863. (49) Peng, Y.-F.; Zhao, S.; Li, K.; Liu, L.; Li, B.-L.; Wu, B. Construction of Cu(II), Zn(II) and Cd(II) Metal–Organic Frameworks of Bis(1,2,4-triazol-4-yl)ethane and Benzenetricarboxylate: Syntheses, Structures and Photocatalytic Properties. CrystEngComm 2015, 17, 2544−2552. (50) Liu, L.; Peng, Y.-F.; Lv, X.-X.; Li, K.; Li, B.-L.; Wu, B. Construction of Three Coordination Polymers Based on Tetranuclear Copper(II) Clusters: Syntheses, Structures and Photocatalytic Properties. CrystEngComm 2016, 18, 2490−2499. (51) Salah, M. B.; Vilminot, S.; André, G.; RichardPlouet, M.; Mhiri, T.; Takagi, S.; Kurmoo, M. Nuclear and Magnetic Structures and Magnetic Properties of the
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Layered Cobalt Hydroxysulfate Co5(OH)6(SO4)2(H2O)4 and Its Deuterated Analogue, Co5(OD)6(SO4)2(D2O)4. J. Am. Chem. Soc. 2006, 128, 7972–7981. (52) Weng, D.-F.; Wang, Z.-M.; Gao, S. Framework-Structured Weak Ferromagnets. Chem. Soc. Rev. 2011, 40, 3157–3181. (53) Abellán, G.; Martí-Gastaldo, C.; Ribera, A.; Coronado, E. Hybrid Materials Based on Magnetic Layered Double Hydroxides: A Molecular Perspective. Acc. Chem. Res. 2015, 48, 1601−1611. (54) Li, K.; Lv, X.-X.; Shi, L.-L.; Liu, L.; Li, B.-L.; Wu, B. A New Strategy to Obtain Tetranuclear Cobalt(II) Metal–Organic Frameworks Based on the [Co4(μ3-OH)2] Cluster: Synthesis, Structures and Properties. Dalton Trans. 2016, 45, 15078−15088. (55) Yang, L.-X.; Zhu, Y.-J.; Tong, H.; Wang, W.-W.; Cheng, G.-F. Low Temperature Synthesis of Mn3O4 Polyhedral Nanocrystals and Magnetic Study. J. Solid State Chem. 2006, 179, 1225–1229. (56) Chiang, C.-H.; Tzeng, Y.-W.; Yang, C.-I.; Nakano, M.; Wan, W.-L.; Lai, L.-L.; Lee, G.-H. The synthesis of three new Cu5, Cu8 and Cu12 clusters via the use of a semi-flexible aminotriazinebased bis-methylpyridine ligand. Dalton Trans. 2017, 46, 1237−1248. (57) Canaj, A. B.; Tzimopoulos, D. I.; Philippidis, A.; Kostakis, G. E.; Milios, C. J. Employment of a New Tripodal Ligand for the Synthesis of Cobalt(II/III), Nickel(II), and Copper(II) Clusters: Magnetic, Optical, and Thermal Properties. Inorg. Chem. 2012, 51, 10461−10470. (58) Zhang, X.-M.; Li, P.; Gao, W.; Liu, J.-P.; Gao, E.-Q. A New Cube-Based Dodecanuclear Cobalt(II) Cluster with Azide and Tetrazolate Ligands Exhibiting Ferromagnetic Ordering. Dalton Trans. 2015, 44, 511−514.
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Crystal Growth & Design
Table 1. Crystallographic Data and Structural Refinements of Complexes 1–8 complex formula
1
2
C12H17O13Mn1.5
C12H13O12.5Cu3
3 C24H31O25Zn3.5
4 C24H22N6O11Zn2
formula weight
451.66
547.85
948.28
701.21
crystal system
triclinic
trigonal
triclinic
triclinic
space group
P-1
P-3
P-1
P-1
a (Å)
4.6446(16)
8.895(2)
11.390(2)
11.279(8)
b (Å)
13.014(5)
8.895(2)
12.684(2)
11.602(8)
c (Å)
14.321(5)
11.460(5)
12.893(2)
12.022(9)
α (º)
66.416(4)
90
87.979(2)
70.675(9)
β (º)
84.772(4)
90
67.951(2)
65.875(7)
γ (º)
80.582(4)
120
70.430(2)
69.059(8)
V (Å3)
782.3(5)
785.2(5)
1617.9(5)
1309.0(17)
Z
2
2
2
2
Dc (g cm−3)
1.917
2.317
1.947
1.779
μ (mm−1)
1.304
4.099
2.672
1.907
reflections/ unique
4880/ 3452
4811/ 1222
10409/ 7354
8316/ 5845
Rint
0.0266
0.0851
0.0302
0.0207
data/ restraint/ param
3452/ 12/ 259
1222 / 1/ 87
7354/ 18/ 496
5845/ 4/ 391
R1, wR2 [I >2σ(I)]
0.0489, 0.1360
0.0574, 0.1356
0.0480, 0.1151
0.0502, 0.1453
R1, wR2 (all data)
0.0633, 0.1505
0.0883, 0.1537
0.0740, 0.1302
0.0678, 0.1574
GOF on F2
1.102
1.076
1.063
1.065
largest difference in peak and hole (e Å−3) complex
0.714, −0.824
0.859, −1.300
1.918, −0.771
2.625, −0.567
formula
C20H25N5O13Cd2
formula weight
768.25
1439.95
1480.78
1480.78
crystal system
monoclinic
triclinic
triclinic
triclinic
space group
P21/n
P1
P-1
P-1
a (Å)
11.8276(8)
7.488(4)
11.7241(15)
11.887(5)
b (Å)
14.1076(9)
10.006(5)
14.677(2)
12.930(6)
c (Å)
16.5266(11)
23.081(12)
19.290(3)
21.037(9)
α (º)
90
89.617(6)
79.327(2)
103.317(5)
β (º)
104.8590(10)
86.838(6)
82.002(2)
97.498(6)
6
5
C61H62N6O24Co3
7 C48H68N4O34Co4
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8 C48H68N4O34Co4
Crystal Growth & Design 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
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γ (º)
90
70.213(5)
68.331(2)
90.347(5)
V (Å3)
2665.4(3)
1624.7(14)
3022.2(7)
3117(2)
Z
4
1
2
2
Dc (g cm−3)
1.914
1.472
1.627
1.578
μ (mm−1)
1.670
0.841
1.179
1.143
reflections/ unique
16337/ 6166
10297/ 8624
19279/ 13544
19783/ 13966
Rint
0.0185
0.0184
0.0329
0.0224
data/restraint/param
6166/ 9/ 368
8624/ 18/ 872
13544/ 6/ 823
13966/ 6/ 817
R1, wR2 [I >2σ(I)]
0.0324, 0.0871
0.0410, 0.1061
0.0629, 0.1554
0.0541, 0.1520
R1, wR2 (all data)
0.0409, 0.0930
0.0621, 0.1220
0.1078, 0.1847
0.0810, 0.1695
GOF on F2
1.047
1.019
1.028
1.091
largest difference in peak and hole (e Å−3)
1.510, −0.997
0.747, −0.346
1.346, −0.731
0.895, −0.672
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Crystal Growth & Design
For Table of Contents Use Only
Hydrolysis Controlled Synthetic Strategy and Structural Variation of Hydroxyl-Metal Clusters and Metal-Organic Frameworks Based on Tripodal Ether-Linked 1,3,5-Tris(carboxymethoxy)benzene Jia-Yao Zhang, Xue-Li Ma, Zhao-Xi Wang, Xiang He, Min Shao, and Ming-Xing Li* Eight coordination polymers were assembled by a tripodal ether-linked tricarboxylate ligand that exhibits nine types of coordination modes. The ether-linked tricarboxylic acid is a good flexible multidentate ligand in constructing various coordination networks. Five complexes have μ3- and μ2-hydroxyl groups. A hydrolysis controlled synthesis strategy is suggested based on Ksp values of metal hydroxides. Temperature has great influence on the hydrolytic reactions of cobalt complexes 6–8. PXRD study reveals the hydrolysis mechanism. Four complexes present antiferromagnetic and/or ferromagnetic interactions.
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