Temperature-Driven Assembly of Ln (III)(Ln= Nd, Eu, Yb) Coordination

ARTICLE pubs.acs.org/crystal

Temperature-Driven Assembly of Ln(III) (Ln = Nd, Eu, Yb) Coordination Polymers of a Flexible Azo Calix[4]arene Polycarboxylate Ligand Lei-Lei Liu,† Zhi-Gang Ren,† Lian-Wen Zhu,† Hui-Fang Wang,† Wen-Yan Yan,† and Jian-Ping Lang*,†,‡ † ‡

College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, Jiangsu, P. R. China State Key Laboratory of Coordination Chemistry, Nanjing University, Nanjing 210093, P. R. China

bS Supporting Information ABSTRACT: Solvothermal reactions of LnCl3 3 6H2O (Ln = Nd, Eu, Yb) with equimolar amounts of 5,11,17,23-tetrakis[(m-carboxyphenyl)azo]-25,26,27,28-tetrahydroxycalix[4]arene (H4L) at 90 or 140 °C gave rise to a set of six lanthanide(III) coordination polymers {[Nd2ClL(HCOO)(DMF)3(H2O)] 3 0.5DMF 3 MeCN 3 1.5H2O}n (1), {[Ln2ClL(HCOO)(DMF)] 3 sol}n (2: Ln = Eu, sol =0.5MeCN 3 1.5H2O; 3: Ln = Yb, sol = 1.5H2O), and {[H3O][LnL(H2O)] 3 DMF 3 MeCN 3 H2O}n (4: Ln = Nd; 5: Ln = Eu; 6: Ln = Yb). Complexes 1
6 were characterized by elemental analysis, IR, powder X-ray diffraction, and single-crystal X-ray diffraction. Compounds 1
3 have two-dimensional (2D) networks in which [Nd6Cl4L2(DMF)12(H2O)2] units (1) or [Ln6Cl4L2(DMF)2] (Ln = Eu (2), Yb (3)) are interlinked by the carboxyl groups of formates. Compounds 4
6 exhibit 2-fold interpenetrating 2D networks in which each [Ln4L(H2O)4] “four-flier pinwheel” unit works as a planar eight-connecting node to connect its eight equivalents via four L ligands. The formation of 1
6 provided an interesting insight into the temperature effect on the construction of lanthanide(III)/polycarboxylate coordination polymers under solvothermal conditions.

’ INTRODUCTION The design and synthesis of coordination polymers have attracted considerable interest not only for their diversity of architectures and topologies1 but also for their fascinating potential applications in gas storage/adsorption,2 catalysis,3 separation,4 drug delivery,5 and so on. In fact, the ultimate aim of supramolecular chemistry is to control the higher structures of the target products and to investigate the relationship between structure and property. Thus, how to rationally design and synthesize coordination polymers with desired properties has been a longterm challenge. As we all know, many factors such as metal ion,6 organic linker,7 counteranion,6a,8 solvent,7a,9 metal/ligand ratio,10 pH value,11 and reaction time12 exert great impacts on the structural topologies of the resulting coordination polymers. As for temperature, its effect on forming the coordination polymers has not been intensively explored, though some reports described how the reaction temperature affects the generation of different coordination polymers.13 On the other hand, in the past decades, much attention has been paid to the supramolecular chemistry of calixarenes due to not only their relevance to materials science, separation technology, biomimetics, and structural biology but also their remarkable conformational diversity.14,15 Calixarenes are highly preorganized compounds, showing a controllable conformational behavior, which could be beneficial for the rational construction of metal coordination polymers. In the case of calix[4]arene, it possesses the cone, partial cone, 1,2-alternate, and 1,3-alternate conformations that can be converted to each other through changing functional groups, temperatures, solvents, and so on.15h
l For r 2011 American Chemical Society

example, Weber reported that the cone and 1,2-alternate conformations of 5,11,17,23-tetra-tert-butyl-26,28-dihydroxy-25,27dimethoxycalix[4]arene were dependent on crystallization solvents.15g In addition, a number of metal coordination polymers derived from pH-dependent assembly of main group, transition, or lanthanide metals with p-sulfonatocalix[4]arenes have been reported.14b,d,15b,15e However, studies engaged in temperaturedependent construction of coordination polymers containing calix[4]arenes are quite rare. In this article, we delicately chose an interesting calix[4]arene, 5,11,17,23-tetrakis[(m-carboxyphenyl)azo]-25,26,27,28-tetrahydroxycalix[4]arene (H4L, Scheme 1), as the linker. The m-carboxyphenyl groups of the four long arms in this ligand can rotate along their C
N and/or C
O bonds to form four possible conformations (Scheme 2). We anticipated that such conformational changes of the calix[4]arene core could be controlled by regulating reaction temperatures under the solvothermal conditions, which may lead to the generation of various coordination polymers with different poly-dimensional topological structures. The solvothermal reactions of H4L with LnCl3 3 6H2O (Ln = Nd, Eu, Yb) at 90 or 140 °C gave rise to six coordination polymers with different topological structures {[Nd2ClL(HCOO)(DMF)3(H2O)] 3 0.5DMF 3 MeCN 3 1.5H2O}n (1), {[Ln2ClL(HCOO)(DMF)] 3 sol}n (2: Ln = Eu, sol = 0.5MeCN 3 1.5H2O; 3: Ln = Yb, sol =1.5H2O), and {[H3O][LnL(H2O)] 3 DMF 3 MeCN 3 H2O}n (4: Ln = Nd; 5: Ln = Eu; Received: March 12, 2011 Revised: June 1, 2011 Published: June 10, 2011 3479

dx.doi.org/10.1021/cg200308k | Cryst. Growth Des. 2011, 11, 3479–3488

Crystal Growth & Design Scheme 1. Structure of the H4L Ligand

ARTICLE

thoroughly with MeCN and dried in air. Yield: 5 mg (56%, based on NdCl3). Anal. Calcd. for C69.5H69.5N12.5ClNd2O20: C, 48.42; H, 4.06; N, 10.15. Found: C, 48.39; H, 4.33; N, 9.92. IR (KBr disk): 3436 (m), 2780 (w), 1657 (m), 1593 (m), 1551 (s), 1438 (s), 1396 (m), 1307 (m), 1119 (m), 1077 (w), 890 (w), 791 (w), 778 (m), 676 (w), 504 (w) cm
1.

Preparation of {[Eu2ClL(HCOO)(DMF)] 3 0.5MeCN 3 1.5H2O}n (2). Compound 2 (red prisms) was prepared in the same way as 1,

except using EuCl3 3 6H2O (4 mg, 0.01 mmol) instead of NdCl3 3 6H2O. Yield: 4 mg (53%, based on EuCl3). Anal. Calcd. for C61H48.5N9.5ClEu2O16.5: C, 48.27; H, 3.22; N, 8.77. Found: C, 48.69; H, 3.63; N, 8.55. IR (KBr disk): 3428 (m), 2827 (w), 1659 (m), 1596 (m), 1548 (s), 1470 (s), 1385 (m), 1267 (m), 1116 (m), 1020 (w), 913 (w), 771 (w), 688 (m), 666 (w), 505 (w) cm
1. Preparation of {[Yb2ClL(HCOO)(DMF)] 3 1.5H2O}n (3). Compound 3 (red prisms) was prepared in the same way as 1, except using YbCl3 3 6H2O (4 mg, 0.01 mmol) instead of NdCl3 3 6H2O. Yield: 5 mg (63%, based on YbCl3). Anal. Calcd. for C60H47N9ClO16.5Yb2: C, 46.81; H, 3.08; N, 8.19. Found: C, 46.51; H, 3.18; N, 8.25. IR (KBr disk): 3425 (m), 2824 (w), 1656 (m), 1594 (m), 1543 (s), 1466 (s), 1383 (m), 1265 (m), 1114 (m), 1019 (w), 912 (w), 770 (w), 687 (m), 665 (w), 504 (w) cm
1.

Preparation of {[H3O][NdL(H2O)] 3 DMF 3 MeCN 3 H2O}n (4).

Scheme 2. Possible Conformations of Each Arm in the L Liganda

Compound 4 (orange blocks) was prepared in a manner similar to that described for 1, using the same components in the same molar ratio except the reaction temperature was fixed at 140 °C. Yield: 7 mg (55%, based on NdCl3). Anal. Calcd. for C61H53N10NdO16: C, 55.24; H, 4.03; N, 10.56. Found: C, 55.27; H, 3.83; N, 10.61. IR (KBr disk): 3376 (m), 2780 (w), 1658 (m), 1592 (m), 1550 (s), 1438 (s), 1393 (m), 1305(m), 1273 (m), 1116 (m), 1074 (w), 892 (w), 795 (w), 777 (m), 675 (w), 503 (w) cm
1.

Preparation of {[H3O][EuL(H2O)] 3 DMF 3 MeCN 3 H2O}n (5).

a

(a) The trans
cis conformation. (b) The trans
trans conformation. (c) The cis
trans conformation. (d) The cis
cis conformation.

6: Ln = Yb). The results revealed evident temperature effects in the formation of these lanthanide(III) coordination polymers and the rich structural variety of the title ligand H4L. Herein we describe the temperature-oriented reactions along with the crystal structures and thermal properties of 1
6.

’ MATERIALS AND METHODS General Procedure. The ligand H4L was prepared according to the literature method.16 All chemicals and reagents were obtained from commercial sources and used as received. IR spectra were recorded with a Varian 1000 FT-IR spectrometer as KBr disks (4000
400 cm
1). The elemental analyses for C, H, and N were performed on an EA1110 CHNS elemental analyzer. Powder X-ray diffraction (XRD) was performed using a PANalytical X’Pert PROMPD system (PW3050/6x). Thermal analysis was performed with a Perkin-Elmer TG-DTA6300 thermogravimetric analyzer at a heating rate of 10 °C min
1 and a flow rate of 100 cm3 min
1 (N2). Preparation of {[Nd2ClL(HCOO)(DMF)3(H2O)] 3 0.5DMF 3 MeCN 3 1.5H2O}n (1). A 10 mL Pyrex glass tube was loaded with

NdCl3 3 6H2O (4 mg, 0.01 mmol), H4L (10 mg, 0.01 mmol), 1 M HCl (0.7 mL), and 2 mL of DMF/MeCN (1:1 V/V), forming a clear red solution. The tube was then sealed and heated in an oven to 90 °C for one day and cooled to ambient temperature at a rate of 5 °C h
1. The red prisms of 1 were formed one day later, which were collected and washed

Compound 5 (orange blocks) was prepared in a manner similar to that described for 2, using the same components in the same molar ratio except the reaction temperature was fixed at 140 °C. Yield: 8 mg (59%, based on EuCl3). Anal. Calcd. for C61H53N10EuO16: C, 54.92; H, 4.00; N, 10.50. Found: C, 55.37; H, 3.91; N, 10.61. IR (KBr disk): 3378 (m), 2783 (w), 1659 (m), 1591 (m), 1551 (s), 1439 (s), 1396 (m), 1301(m), 1270 (m), 1111 (m), 1071 (w), 890 (w), 799 (w), 777 (m), 671 (w), 501 (w) cm
1.

Preparation of {[H3O][YbL(H2O)] 3 DMF 3 MeCN 3 H2O}n (6).

Compound 6 (orange blocks) was prepared in a manner similar to that described for 3, using the same components in the same molar ratio except the reaction temperature was fixed at 140 °C. Yield: 8 mg (57%, based on YbCl3). Anal. Calcd. for C61H53N10O16Yb: C, 54.06; H, 3.94; N, 10.34. Found: C, 54.29; H, 3.63; N, 10.65. IR (KBr disk): 3379 (m), 2781 (w), 1659 (m), 1593 (m), 1552 (s), 1438 (s), 1396 (m), 1306(m), 1275 (m), 1118 (m), 1076 (w), 893 (w), 797 (w), 777 (m), 676 (w), 504 (w) cm
1. X-ray Crystal Structure Determination. Single crystals of 1
6 were obtained directly from the above preparations. All measurements were made on a Rigaku Mercury CCD X-ray diffractometer by using graphite monochromated Mo KR (λ = 0.071073 nm). These crystals were mounted on glass fibers and cooled at 223 K for 1
6 in a liquid nitrogen stream. Diffraction data were collected at ω mode with a detector distance of 35 mm to the crystal. Cell parameters were refined by using the program CrystalClear (Rigakuand MSC, version 1.3, 2001). The collected data were reduced by using the program CrystalClear (Rigaku and MSC, Ver.1.3, 2001), and an absorption correction (multiscan) was applied. The reflection data were also corrected for Lorentz and polarization effects. The crystal structures of 1
6 were solved by direct method17 refined on F2 by full-matrix least-squares using anisotropic displacement parameters for all non-hydrogen atoms. In 2 and 3, one carboxylate group and one phenyl group were found to be disordered over two positions with an occupancy factor of 0.506/0.494 (2) and 0.510/490 (3) for C26 3480

dx.doi.org/10.1021/cg200308k |Cryst. Growth Des. 2011, 11, 3479–3488

Crystal Growth & Design

ARTICLE

Table 1. Summary of Crystallographic Data for 1
6 compound

1

2

3

4

5

6

empirical formula

C139H139N25Cl2Nd4O40 C122H95N19Cl2Eu4O33 C120H92N18Cl2O33Yb4 C61H50N10NdO16

C61H50N10EuO16

formula weight

3447.62

3033.95

3077.18

1323.35

1331.07

1352.19

crystal system

monoclinic

orthorhombic

orthorhombic

tetragonal

tetragonal

tetragonal

space group

P21/n

Pnma

Pnma

I4/m

I4/m

I4/m

a (Å)

15.604(3)

13.003(3)

12.768(3)

11.2863(16)

11.2815(16)

11.3086(16)

b (Å)

11.804(2)

16.449(3)

16.619(3)

c (Å)

42.692(9)

40.207(8)

39.917(8)

50.133(10)

49.769(10)

49.019(10)

β (°) V (Å3)

92.43(3) 7856(3)

8600(3)

8470(3)

6386.0(4)

6334.2(4)

6268.8(4)

Z

2

2

2

4

4

4

T (K)

223(2)

223(2)

223(2)

223(2)

223(2)

223(2)

Fcalc (g/cm3)

1.457

1.172

1.207

1.377

1.396

1.433

F(000)

3484.0

3020.0

3032.0

2696.0

2708.0

2736.0

μ (MoKR, mm
1) 1.416

1.532

2.281

0.886

1.064

1.566

total reflections

30585

35973

8228

8244

8097

unique reflections 13646 (Rint = 0.0598) no. of observations 10145

7468 (Rint = 0.0549) 5557

7668 (Rint = 0.0589) 6582

2724 (Rint = 0.0638) 2808 (Rint = 0.0610) 2788 (Rint = 0.0634) 2185 2293 2334

no. of parameters

991

501

473

225

225

224

R1a

0.0838

0.0793

0.0787

0.0822

0.0791

0.0771

wR2b

0.1924

0.1654

0.2166

0.1651

0.1966

0.1819

GOFc

1.113

1.028

1.065

1.068

1.097

1.143

29682

C61H50N10O16Yb

R1 = Σ||Fo|
|Fc||/Σ|Fo|. b wR2 = {Σw(Fo2
Fc2)2/Σw(Fo2)2}1/2. c GOF = {Σw(Fo2
Fc2)2/(n
p)}1/2, where n = number of reflections and p = total numbers of parameters refined. a

and O5
O6/C26A and O5A
O6A, C21
C25/C21A
C25A. The H atoms of all the H2O molecules in 1
6 and the H atoms of the protonated water molecule (O3W) in 4
6 were located from Fourier maps. All other H atoms were introduced at the calculated positions and included in the structure-factor calculations. Compounds 2 and 3 showed very large solvent accessible volumes in their structures. This may be ascribed to the partial evaporation of the MeCN and H2O solvent molecules during the measurements. All the calculations were performed on a Dell workstation using the SHELXTL-97 crystallographic software package. A summary of key crystallographic information for 1
6 was given in Table 1. Selected bond lengths for 1
6 were listed in Table 2.

’ RESULTS AND DISCUSSION Synthetic and Spectral Aspects. In all six reactions reported in this article, we maintained the molar ratio of Ln/H4L at 1:1 and the pH value at ca. 1.0. Solvothermal reactions of LnCl3 3 6H2O with H4L (Ln = Nd, Eu, Yb) at 90 °C for one day produced red crystals of 1 (56% yield), 2 (53% yield), and 3 (63% yield), respectively. When the reaction temperature was raised to 140 °C, the orange crystals of 4 (57% yield), 5 (59% yield), or 6 (57% yield) were generated through procedures similar to those described for 1
3. We also attempted crystallization at other pH values but always failed to form any crystals. When the pH values were decreased to 0.5 or increased to 6.5
7.0, only red or orange clear solutions were obtained. As described later in this paper, the bridging anion (HCOO
) in 1
3 may be derived from the decomposition of DMF during the solvothermal reactions.9b It is worth noting that decreasing the temperature from 140 to 120 °C or increasing the temperature from 140 to 170 °C could form the same products 4
6 with relatively lower yields. However, when the temperature was decreased to 60 °C,

only orange precipitates were isolated and their PXRD patterns were inconsistent with those of 1
6. Compounds 1
3 could not be converted into their corresponding ones of 4
6 through heating the mixture of each of 1
3 up to 140 °C under similar solvent and pH conditions and vice versa. Compounds 1
6 were stable toward oxygen and moisture and almost insoluble in common organic solvents. The elemental analyses of 1
6 were consistent with their chemical formula. The IR spectra of 1
6 showed peaks in the range of 1655
1659 cm
1 and 1385
1396 cm
1, suggesting they all contain coordinated carboxylic groups.11g The middle peaks in the range of 1591
1596 cm
1 were assigned to the asymmetric NdN vibration of complexes 1
6.18 The identities of 1
6 were further confirmed by single-crystal diffraction analysis. The PXRD patterns of 1
6 were matched with the simulated patterns generated from their single crystals data (Figure S1, Supporting Information). Crystal Structure of 1. Compound 1 crystallizes in the monoclinic space group P21/n, and its asymmetric unit contains one [Nd2ClL(HCOO)(DMF)3(H2O)] unit, one MeCN, half a DMF, and three halves of H2O solvent molecules. As shown in Figure 1a, Nd1 adopts a dodecahedral coordination geometry and is coordinated by three O (O2, O8, O11) atoms of three bridging carboxylate groups from three different L ligands, two O (O5, O6) atoms from one chelating carboxylate group from the forth L ligand, two O (O13A, O14) atoms of two bridging HCOO
anions, and one O atom from one H2O molecule. Nd2 takes a coordination geometry similar to that of Nd1, coordinated by one Cl atom, three O (O3, O9, O12) atoms of three bridging carboxylate groups from two different L ligands, one O atom of one bridging HCOO
ligand, three O atoms from three DMF molecules (Figure 1b). Besides, it is noted that there are two weak interactions between Nd1 and O12 (2.837(6) Å) and between Nd2 and O13 (2.814(6) Å). For Nd1, the mean 3481

dx.doi.org/10.1021/cg200308k |Cryst. Growth Des. 2011, 11, 3479–3488

Crystal Growth & Design

ARTICLE

Table 2. Selected Bond Lengths (Å) for 1
6a Complex 1 Nd(1)
O(2)

2.384(6)

Nd(1)
O(11)

2.417(6)

Nd(1)
O(14)

2.429(6)

Nd(1)
O(8)

2.454(6)

Nd(1)
O(13A) Nd(1)
O(5)

2.488(7) 2.538(7)

Nd(1)
O(1W) Nd(1)
O(6)

2.503(7) 2.559(8)

Nd(1)
O(12)

2.837(6)

Nd(2)
O(3B)

2.386(7)

Nd(2)
O(16)

2.405(10)

Nd(2)
O(9)

2.439(7)

Nd(2)
O(15)

2.461(6)

Nd(2)
O(17)

2.499(12)

Nd(2)
O(12)

2.525(7)

Nd(2)
Cl(1)

2.527(7)

Nd(2)
O(14)

2.592(6)

Nd(2)
O(13)

2.815(6)

Eu(1)
O(3) Eu(1)
O(6A)

2.303(8) 2.395(12)

Complex 2 Eu(1)
O(9) Eu(1)
O(8B)

2.394(7) 2.440(6)

Eu(1)
O(7)

2.440(6)

Eu(2)
O(5)

2.227(16)

Eu(2)
O(4)

2.227(9)

Eu(2)
O(7)

2.454(6)

Eu(2)
O(8)

2.515(9)

Eu(2)
Cl(1)

2.430(11)

Yb(1)
O(3)

2.265(7)

Yb(1)
O(9)

2.279(10)

Yb(1)
O(6A)

2.301(13)

Yb(1)
O(8B)

2.376(7)

Yb(1)
O(7) Yb(2)
O(4)

2.395(9) 2.120(8)

Yb(2)
O(5) Yb(2)
Cl(1)

2.097(16) 2.374(10)

Yb(2)
O(7)

2.376(8)

Yb(2)
O(8)

2.430(7)

Complex 3

Complex 4 Nd(1)
O(1W)

2.359(10)

Nd(1)
O(3)

2.547(4)

Eu(1)
O(1W)

2.337(10)

Eu(1)
O(3)

2.506(5)

Yb(1)
O(1W)

2.317(9)

Yb(1)
O(3)

2.448(4)

Nd(1)
O(2)

2.497(5)

Eu(1)
O(2)

2.446(6)

Yb(1)
O(2)

2.348(5)

Complex 5

Complex 6

Symmetry codes for 1: A:
x
3/2, y + 1/2,
z + 1/2; B:
x
3/2, y
1/2,
z + 1/2; for 2: A: x + 1/2,
y + 1/2,
z + 3/2; B: x + 1/2, y,
z + 3/2; C: x,
y + 1/2, z; for 3: A: x
1/2,
y + 3/2,
z + 5/2; B: x
1/2, y,
z + 5/2; C: x,
y + 3/2, z; for 4: A:
y + 2, x, z; B: y,
x + 2, z; C:
x + 2,
y + 2, z; for 5: A: y + 1,
x + 1, z; B:
y + 1, x
1, z; C:
x + 2,
y, z; for 6: A: A:
y + 2, x, z; B: y,
x + 2, z; C:
x + 2,
y + 2, z. a

Nd
O bond length (2.472(6) Å) (Table 2) is longer than that of the corresponding one in [Pd(μ-OAc)4Nd(H2O)(μ,η2-OAc)]2 3 2 HOAc (2.465(2) Å).19a For Nd2, the mean Nd
O and Nd
Cl bond lengths (2.471(7) Å vs 2.527(7) Å) are shorter than those of the corresponding ones in {[Nd(HGl)2(H2O)3Cl]Cl2}2 (2.510(2) Å vs 2.871(2) Å, Gl = glycine).19b The calix[4]arene core of 1 adopts a flattened cone conformation in which opposed phenyl rings have parallel or sharply inclined positions (Figure 1a,b), which were observed in p-tetrakis(phenylazo)calix[4]arene.19c And the mean NdN (1.255(10) Å) bond length of 1 is slightly longer than that observed in p-tetrakis(phenylazo)calix[4]arene (1.243(4) Å).19c Two [Nd(H2O)] subunits and four [Nd(DMF)3Cl] subunits are linked by two L ligands to form a hexanuclear [Nd6Cl4L2(DMF)12(H2O)2] unit (Figure 1c). Each unit interconnects its

equivalents via two bridging HCOO
anions and sharing [Nd(DMF)3Cl] subunits to form a one-dimensional (1D) [Nd4Cl2L2(HCOO)2(DMF)6(H2O)2]n chain extending along the a axis (Figure 1d). The arms of L in 1 adopt trans
cis (Scheme 2a) and trans
trans (Scheme 2b) conformations. The carboxylate groups of the L ligand of part A in Figure 1d display the bridging coordination mode, whereas those in part B exhibit the bridging and chelating coordination modes. The dihedral angle of the two phenyl groups of azobenzene in part A (6.41(7)°) is much smaller than that in part B (86.52(2)°). Furthermore, each Nd3+ in such a chain interlinks its equivalents via carboxyl groups of the L ligands to form a two-dimensional (2D) network extending along the ab plane (Figure 1e). Each layer is further stacked along the c axis to form 1D channels (4.74  5.88 Å), which are calculated by the Platon program20 to have an effective solvent accessible volume of 1486.2 Å3 per unit cell (18.9% of the total cell volume) and are filled with DMF, MeCN, and H2O solvent molecules. Crystal Structures of 2 and 3. Crystallized in the orthorhombic space group Pnma, the asymmetric unit for either 2 or 3 contains half a [Ln2ClL(HCOO)(DMF)] molecule (Ln = Eu, Yb), a quarter of H2O, half a H2O solvent molecules (2 and 3), and one-quarter of MeCN molecule (2). As the crystal structures of 2 and 3 are quite similar, only the structure of 3 is shown in Figure 2. The coordination environments of Ln3+ in 2 and 3 are different from those of Nd3+ in 1. Eu1 or Yb1 has a distorted monocapped octahedral coordination geometry, coordinated by four O atoms of four carboxylate groups from four different L ligands, two O atoms from two μ,μ,η,η-HCOO
anions as well as one O atom from one DMF molecule (Figure 2a). In contrast, Eu2 or Yb2 adopts a distorted pentagonal bipyramidal coordination geometry and is coordinated by one Cl atom, four O atoms of four carboxylate groups from two different L ligands, and two O atoms of one μ,μ,η,η-HCOO
ligand (Figure 2b). In the crystal structure of 2, the mean Eu1
O bond length (2.394(4) Å) is shorter in comparison with a related structure of {[Eu3(MeCHdCHCO2)9(H2O)4] 3 H2O 3 EtOH}n (2.480(8) Å),21a while the mean Eu2
O bond length (2.355(7) Å) is shorter than that of [EuCd(C8H7O3)5(phen)(H2O)] (2.400(5) Å, C8H7O3 = 4-methoxybenzoato, phen =1,10-phenanthroline).21b The observed Eu
Cl bond length (2.430(11) Å) is shorter than that of [Eu8L4(1,4-BDC)2Cl8(MeOH)12]Cl4 3 2MeOH 3 18H2O (2.686(2) Å, H2L = bis-(5-bromo-3-methoxysalicylidene)ethylene1,2-phenylenediamine, 1,4-H2BDC = 1,4-benzenedicarboxylic acid).21c For 3, the average Yb1
O bond length (2.312(6) Å) is shorter than that of a comparable complex of Na[Yb(C2O4)2(H2O)] 3 3H2O (2.378(3) Å),21d whereas the mean Yb2
O bond length (2.207(7) Å) is shorter than that of [Yb3(BDC)3.5(OH)2(H2O)2] 3 H2O (2.342(3) Å, BDC = 1,4-benzenedicarboxylate).21e The Yb
Cl bond length (2.374(10) Å) is shorter than that of [Yb3L3(OAc)2Cl] 3 3H2O 3 1.5MeOH 3 0.5MeCN (2.583(2) Å, H2L = N,N0 -bis(5-bromo-3-methoxysalicylidene)phenylene-1,2-diamine).22 The carboxylate groups of the L ligands in 2 and 3 only show the bridging coordination mode. Two [Ln(DMF)] subunits and four [LnCl] subunits are linked by two L ligands to form another hexanuclear [Ln6Cl4L2(DMF)2] unit (Figure 2c). Such a unit links its equivalents via two bridging HCOO
anions and sharing [Ln(DMF)3Cl] subunits to form a 1D chain [Ln4Cl2L2(HCOO)2(DMF)2]n extending along the b axis (Figure 2d). The arms of L in 2
3 adopt two conformations similar to those of 1. The dihedral angles of the two phenyl groups of azobenzene in part A 3482

dx.doi.org/10.1021/cg200308k |Cryst. Growth Des. 2011, 11, 3479–3488

Crystal Growth & Design

ARTICLE

Figure 1. (a) View of the coordination environment of the Nd1 center in 1 with a labeling scheme and 30% thermal ellipsoids. Symmetry code: (A)
x + 5/2, y + 1/2,
z + 1/2. (b) View of the coordination environments of the Nd2 center in 1. (c) View of one hexanuclear [Nd6Cl4L2(DMF)12(H2O)2] unit of 1. Symmetry codes: A:
x
3/2, y
1/2,
z + 1/2; B: x
1, y, z; C: x
2, y, z. All hydrogen atoms and the coordinated DMF and H2O molecules are omitted for clarity. (d) View of a section of the 1D chain extending along the a axis. (e) View of a 2D network of 1 extending along the ab plane. The red and green balls represent oxygen and chlorine atoms, whereas the purple dodecahedral represents the Nd atom. 3483

dx.doi.org/10.1021/cg200308k |Cryst. Growth Des. 2011, 11, 3479–3488

Crystal Growth & Design

ARTICLE

Figure 2. (a) View of the coordination environment of the Yb1 center in 3 with labeling schemes and 30% thermal ellipsoids. Symmetry code: (A)
x + 2,
y + 3/2, z. (b) View of the coordination environment of the Yb2 center in 3. (c) View of one hexanuclear [Yb6Cl4L2(DMF)2] unit of 3. Symmetry codes: A: x, y
1, z; B: x + 1/2,
y + 3/2,
z + 5/2; C: x + 1/2,
y + 1/2,
z + 5/2. All hydrogen atoms and the coordinated DMF molecules are omitted for clarity. (d) View of a section of the 1D chain extending along the b axis. (e) View of a 2D network of 1 extending along the ab plane. The red and green balls represent oxygen and chlorine atoms, whereas the purple monocapped octahedral or pentagonal bipyramidal represents the Yb atom. 3484

dx.doi.org/10.1021/cg200308k |Cryst. Growth Des. 2011, 11, 3479–3488

Crystal Growth & Design

ARTICLE

Figure 3. (a) View of the coordination environment of each Yb center in 6 with labeling schemes and 30% thermal ellipsoids. Symmetry code: (A)
x + 2,
y + 2,
z; (B)
y, x + 2, z; (C) y,
x + 2, z. (b) View of one [Yb4L(H2O)4] “four-flier pinwheel” unit of 6. Symmetry codes: (A) x
1, y + 1, z; (B) x, y + 2, z; (C) x + 1, y + 1, z. (c) View of a single 2D layer in 6 extending along the ab plane. The purple monocapped square antiprism represents one Yb atom. (d) View of the 2-fold interpenetrating of the two 2D layers in 6 extending along the ab plane. The red balls represent oxygen atoms whereas the purple monocapped square antiprism represents the Yb atom. All hydrogen atoms are omitted for clarity.

and part B (63.56(2)o for 2 and 64.68(8)o for 3) are comparable. Each Ln3+ in such a 1D chain interconnects its equivalents via two L ligands to form a 2D network extending along the ab plane (Figure 2e). Similar to the structural result of 1, each layer in 2 or 3 stacks along the c axis to afford 1D channels (6.20 Å  6.83 Å for 2 and 6.12 Å  6.72 Å for 3), which are filled with solvent

molecules. The Platon program analysis suggests that approximately 39.4% (2) or 39.2% (3) of the crystal volume is accessible to the solvents, which is much larger than that of 1. Crystal Structures of 4
6. Compounds 4
6 crystallize in the tetragonal space group I4/m, and their asymmetric unit contains one-quarter of a [LnL(H2O)]
anion (4: Ln = Nd; 6: Ln = Eu; 3485

dx.doi.org/10.1021/cg200308k |Cryst. Growth Des. 2011, 11, 3479–3488

Crystal Growth & Design 5: Ln = Yb), one-quarter of a protonated H3O+ cation and a quarter of MeCN, DMF, and H2O solvent molecules. Because the three molecules in 4
6 are structurally similar, exclusively the view of the structure of 6 is presented in Figure 3. The coordination environment of each Ln3+ in 4
6 is different from those of Nd3+ in 1 and Eu3+ and Yb3+ in 2
3. Each Ln center in 4
6 adopts a distorted monocapped square antiprism coordination geometry and is coordinated by eight O atoms of four chelating carboxylate groups from four different L ligands and one O atom from one H2O molecule (Figure 3a). The mean Ln
O bond length (2.467(6) Å for 4, 2.460(7) Å) for 5, and 2.388(8) Å for 6) is comparable to that in [{Nd-(H2O)8}{Nd2L4(H2O)2}]ClO4 3 H2O (2.450(3) Å)22a or [{Eu-(H2O)8}{Eu2L4(H2O)2}]Cl 3 H2O (2.450(3) Å)22b or [{Yb-(H2O)8}{Yb2L4(H2O)2}]ClO4 3 H2O (2.393(3) Å) (L = (3,5-bis(3benzocarboxylate)-4-amino-1,2,4-trizole).22a The carboxylate groups of the L ligands in 4
6 show only the chelating coordination mode. The arms of L in 4
6 only adopt the trans
cis conformation (Scheme 2b). The four Ln(H2O) subunits are linked by four carboxylate groups from one L ligand to form a [Ln4L(H2O)4] “four-flier pinwheel” unit with a 4-fold axis of symmetry running through the center of the L ligand (Figure 3b). Topologically, each unit serves as an unprecedented planar 8-fold node, which links its eight equivalents via four L ligands to form a 2D network extending along the ab plane (Figure 3c). Two such identical networks interpenetrate each other, thereby affording a 2-fold interpenetrating 2D network (Figure 3d). Each layer also stacks along the c axis to yield 1D channels (7.07 Å  8.68 Å for 4, 7.06 Å  8.66 Å for 5 or 7.05 Å  8.59 Å for 6), which are filled with solvent molecules. Although the interpenetration in 4
6 occurs, there are still approximately 24.9% (4), 24.7% (5), or 24.4% (6) of the crystal volume accessible to the solvents. The formation of different structures of 1, 2
3, and 4
6 at different temperatures deserves comments. Compounds 1
3 were produced at lower temperature (90 °C) while compounds 4
6 were generated at higher temperature (140 °C). As described earlier in this article, the structures of 1
3 greatly differed from those of 4
6 in the following aspects. First, compounds 1
3 held the Ln
Cl bonds in their structures, whereas no Ln
Cl bond was observed in the structures of 4
6. Second, compounds 1
3 adopted a hexanuclear [Nd6Cl4L2(DMF)12(H2O)2] unit (1) or [Ln6Cl4L2(DMF)2] (Ln = Eu (2), Yb (3)) units, whereas compounds 4
6 had a tetranuclear [Ln4L(H2O)4] unit. These two results suggest that at higher temperatures the Ln
Cl bonds may be readily cleaved to form the Ln
O bonds, which may be beneficial to the formation of more stable units in the final structures of 4
6. Third, the four carboxylate groups of the L ligands in 1 displayed one chelating and three bridging coordination modes, whereas those in 2
3 showed the bridging coordination mode. However, the four carboxylate groups of the L ligand in 4
6 showed only the chelating coordination mode. These differences implied that for the carboxylate group of the L ligand, the chelating coordination mode may be more stable than the bridging coordination mode at higher temperature.24a Fourth, the conformations of arms of the L ligands in 1
3 showed trans
trans and trans
cis conformations, whereas those in 4
6 exhibited only the trans
cis conformation, which also suggested that at higher temperature the trans
cis conformation may be more stable than the trans
trans conformation. Fifth, compounds 1
3 formed noninterpenetrating 2D network, whereas 4
6 possessed one

ARTICLE

2-fold interpenetrating 2D network. This suggests that at higher temperatures the non-interpenetrating 2D networks of 1
3 may not be stable compared to the interpenetrating 2D networks of 4
6 and may be converted directly into the structures of 4
6, which is consistent with those reported previously.24b From the above-mentioned comparison, it is noted that the temperature effect in this study greatly affected the competition between Ln
Cl and Ln
O bonds, the formation of different Ln-containing subunits, the conformations and coordination modes of the L ligands, and the whole structures of these compounds. Thermal Properties. Thermogravimetric (TGA) experiments were carried out to study the thermal stability of 1
6. As shown in the TGA curve of 1
3 (Figure S2, Supporting Information), the weight loss of 20.36% (1), 8.37% (2), and 6.80% (3) in the range of 25
186 °C (1), 25
151 °C (2), and 25
173 °C (3) was ascribed to the removal of all the coordinated and uncoordinated MeCN, H2O, and DMF molecules (calculated 19.84% for 1, 7.95% for 2, and 6.50% for 3). TGA (Figure S2, Supporting Information) curves revealed that 4
6 were similar, and the azo groups began to decompose upon the 238 °C. For 4
6, the first weight loss of 4.12% (4), 4.24% (5), and 4.97% (6) at 122 °C corresponds to the loss of MeCN and H2O solvent molecules (calculated 4.45% for 4, 4.43% for 5, and 4.36% for 6). Second, the weight loss of 15.80% (4), 14.79% (5), and 14.91% (6) in the range of 123
456 °C corresponds to the removal of the DMF solvent molecules and coordinated H2O molecules plus four azo groups (calculated 15.32% for 4, 15.23% for 5, and 14.99% for 6). Noteworthy, the removal of four azo groups started in the range of 238
259 °C for 1
6, which was consistent with the property of H4L ligand (235 °C).23 The remaining substance with a weight of 21.2% (1), 23.9% (2), 26.1% (3), 12.9% (4), 13.8% (5), and 14.7% (6) corresponded to Ln2O3 (calculated 19.5% for 1, 23.2% for 2, 25.6% for 3, 12.7% for 4, 13.2% for 5, and 14.5% for 6).

’ CONCLUSIONS In this paper, we have demonstrated the formation of six coordination polymers 1
6 from the solvothermal reactions of LnCl3 3 6H2O (Ln = Nd, Eu, Yb) with one flexible upper rim azo-functionalized calix[4]arene polycarboxylate H4L at 90 or 140 °C. In 1, 2, or 3, hexanuclear [Nd6Cl4L2(DMF)12(H2O)2] (1) or [Ln6Cl4L2(DMF)2] (Ln = Eu (2), Yb (3)) units are linked by the carboxyl groups of formates and the L ligands and sharing four Ln centers to form one 2D network. In 4, 5, or 6, each [Ln4L(H2O)4] “four-flier pinwheel” unit acts as a planar eightconnecting node to link its equivalents via four L ligands to form one unique 2-fold interpenetrating 2D network. According to the aforementioned X-ray structural analysis, it is noted that the L ligand shows rich conformational changes when it binds to Ln centers. Its four carboxyl groups can have different coordination modes (chelating and/or bridging), and each arm of the L ligand exhibits two possible conformations (Scheme 2a,b) when it rotates along the C
N and/or C
O bonds. Evidently, the reaction temperature played an important role in the formation of these lanthanide(III) coordination polymers with different topological structures, though the role of the L ligand showing different conformations in 1
6 may not be ruled out. Further studies on the temperaturedriven assembly of lanthanide(III) and other transition metal coordination polymers with the L ligand are underway in our laboratory. 3486

dx.doi.org/10.1021/cg200308k |Cryst. Growth Des. 2011, 11, 3479–3488

Crystal Growth & Design

’ ASSOCIATED CONTENT

bS

Supporting Information. Crystal structural data for 1
6 in CIF format, additional figures and details of characterization. This material is available free of charge via the Internet at http://pubs.acs.org.

’ AUTHOR INFORMATION Corresponding Author

*Fax & Tel: Int. code +86 512 65880089; e-mail: jplang@suda. edu.cn.

’ ACKNOWLEDGMENT The authors thank the National Natural Science Foundation of China (20871088 and 90922018), the Nature Science Key Basic Research of Jiangsu Province for Higher Education (09KJA150002), the Specialized Research Fund for the Doctoral Program of Higher Education of Ministry of Education (20093201110017), and the State Key Laboratory of Coordination Chemistry of Nanjing University for financial support. J.P.L. also greatly appreciates the support for the Qin-Lan and the “333” Projects of Jiangsu Province, the Priority Academic Program Development of Jiangsu Higher Education Institutions, and the “SooChow Scholar” Program and Program for Innovative Research Team of Suzhou University. ’ REFERENCES (1) (a) Lehn, J. M. Supramolecular Chemistry: Concepts and Perspectives; VCH: Weinheim, 1995. (b) Cotton, F. A.; Lin, C.; Murillo, C. Acc. Chem. Res. 2001, 34, 759. (c) Evans, O. R.; Lin, W. B. Acc. Chem. Res. 2002, 35, 511. (d) Gatteschi, D.; Sessoli, R. Angew. Chem., Int. Ed. 2003, 42, 268. (e) F
erey, G.; Mellot-Draznieks, C.; Serre, C.; Millange, F. Acc. Chem. Res. 2005, 38, 217. (f) Tranchemontagne, D. J.; Mendoza-Cort
es, L. J.; O’Keeffe, M.; Yaghi, O. M. Chem. Soc. Rev. 2009, 38, 1257. (g) Moulton, B.; Zaworotko, M. J. Chem. Rev. 2001, 101, 1629–1658. (h) James, S. L. Chem. Soc. Rev. 2003, 32, 276. (2) (a) Zhao, X.; Xiao, B.; Fletcher, A.; Thomas, K. M.; Bradshaw, D.; Rosseinsky, M. J. Science 2004, 306, 1012. (b) Rowsell, J. L. C.; Yaghi, O. M. Angew. Chem., Int. Ed. 2005, 44, 4670. (c) Eddaoudi, M.; Kim, J.; Rosi, N.; Vodak, D.; Wachter, J.; O’Keeffe, M.; Yaghi, O. M. Science 2002, 295, 469. (d) Murray, L. J.; Dinc
a, M.; Long, J. R. Chem. Soc. Rev. 2009, 38, 1294. (e) F
erey, G.; Latroche, M.; Serre, C.; Millange, F.; Loiseau, T.; Percheron-Gu
egan, A. Chem. Commun. 2003, 2976. (f) Morris, R. E.; Wheatley, P. S. Angew. Chem., Int. Ed. 2008, 47, 4966. (g) Li, J. R.; Kuppler, R. J.; Zhou, H. C. Chem. Soc. Rev. 2009, 38, 1477. (3) (a) Wu, C. D.; Hu, A.; Zhang, L.; Lin, W. J. Am. Chem. Soc. 2005, 127, 8940. (b) Forster, P. M.; Cheetham, A. K. Top. Catal. 2003, 24, 79. (c) Ma, L.; Abney, C.; Lin, W. Chem. Soc. Rev. 2009, 38, 1248. (d) Lee, J.; Farha, O. K.; Roberts, J.; Scheidt, K. A.; Nguyen, S. T.; Hupp, J. T. Chem. Soc. Rev. 2009, 38, 1450. (e) Farrusseng, D.; Aguado, S.; Pinel, C. Angew. Chem., Int. Ed. 2009, 48, 7502. (4) (a) Finsy, V.; Verelst, H.; Alaerts, L.; De Vos, D. E.; Jacobs, P. A.; Baron, G. V.; Denayer, J. F. M. J. Am. Chem. Soc. 2008, 130, 7110. (b) Kitaura, R.; Seki, K.; Akiyama, G.; Kitagawa, S. Angew. Chem., Int. Ed. 2003, 42, 428. (5) (a) Horcajada, P.; Serre, C.; Vallet-Regi, M.; Sebban, M.; Taulelle, F.; F
erey, G. Angew. Chem., Int. Ed. 2006, 45, 5974. (b) Horcajada, P.; Serre, C.; Maurin, G.; Ramsahye, N. A.; Balas, F.; Vallet-Reg
i, M.; Sebban, M.; Taulelle, F.; F
erey, G. J. Am. Chem. Soc. 2008, 130, 6774. (6) (a) Du, J. L.; Hu, T. L.; Li, J. R.; Zhang, S. M.; Bu, X. H. Eur. J. Inorg. Chem. 2008, 1059. (b) Livage, C.; Forster, P. M.; Guillou, N.;

ARTICLE

Tafoya, M. M.; Cheetham, A. K.; F
erey, G. Angew. Chem., Int. Ed. 2007, 46, 5877. (c) Huang, X. C.; Zhang, J. P.; Lin, Y. Y.; Yua, X. L.; Chen, X. M. Chem. Commun. 2004, 1100. (d) Xu, B.; Lin, Z. J.; Han, L. W.; Cao, R. CrystEngComm 2011, 13, 440. (e) Haque, E.; Jeong, J. H.; Jhung, S. H. CrystEngComm 2010, 12, 2749. (f) Han, Y. F.; Li, X. Y.; Li, L. Q.; Ma, C. L.; Shen, Z.; Song, Y.; You, X . Z. Inorg. Chem. 2010, 49, 10781. (7) (a) Yang, J.; Li, G. D.; Cao, J. J.; Yue, Q.; Li, G. H.; Chen, J. S. Chem.—A. Eur. J. 2007, 13, 3248. (b) Sun, D.; Zhang, N.; Huang, R. B.; Zheng, L. S. Cryst. Growth Des. 2010, 10, 3699. (c) Yang, J.; Ma, J. F.; Liu, Y. Y.; Ma, J. C.; Batten, S. R. Inorg. Chem. 2007, 46, 6542. (d) Li, L. L.; Yuan, R. X.; Liu, L. L.; Ren, Z. G.; Zheng, A. X.; Cheng, H. J.; Li, H. X.; Lang, J. P. Cryst. Growth Des. 2010, 10, 1929. (8) (a) Wei, K. J.; Ni, J.; Gao, J.; Liu, Y. Z.; Liu, Q. L. Eur. J. Inorg. Chem. 2007, 3868. (b) Sun, H. L.; Wang, Z. M.; Gao, S.; Batten, S. R. CrystEngComm 2008, 10, 1796. (c) Niu, C. Y.; Wu, B. L.; Zheng, X. F.; Wan, X. S.; Zhang, H. Y.; Niu, Y. Y.; Meng, L. Y. CrystEngComm 2009, 11, 1373. (d) Bai, H. Y.; Ma, J. F.; Yang, J.; Liu, Y. Y.; Wu, H.; Ma, J. C. Cryst. Growth Des. 2010, 10, 995. (e) Li, N. Y.; Ren, Z. G.; Liu, D.; Yuan, R. X.; Wei, L. P.; Zhang, L.; Li, H. X.; Lang, J. P. Dalton Trans. 2010, 39, 4213. (9) (a) Lang, J. P.; Xu, Q. F.; Yuan, R. X.; Abrahams, B. F. Angew. Chem., Int. Ed. 2004, 43, 4741. (b) Lin, X. M.; Fang, H. C.; Zhou, Z. Y.; Chen, L.; Zhao, J. W.; Zhu, S. Z.; Cai, Y. P. CrystEngComm 2009, 11, 847. (c) Tzeng, B. C.; Chang, T. Y. Cryst. Growth Des. 2009, 9, 5343. (d) Chen, Y.; Li, H. X.; Liu, D.; Liu, L. L.; Li, N. Y.; Ye, H. Y.; Zhang, Y.; Lang, J. P. Cryst. Growth Des. 2008, 8, 3810. (10) (a) Liu, Y.; Qi, Y.; Su, Y. H.; Zhao, F. H.; Che, Y. X.; Zheng, J. M. CrystEngComm 2010, 12, 3283. (b) Yin, P. X.; Zhang, J.; Li, Z. J.; Qin, Y. Y.; Cheng, J. K.; Zhang, L.; Lin, Q. P.; Yao, Y. G. Cryst. Growth Des. 2009, 9, 4884. (11) (a) Forster, P. M.; Stock, N.; Cheetham, A. K. Angew. Chem., Int. Ed. 2005, 44, 7608. (b) Zheng, B.; Bai, J. F.; Zhang, Z. X. CrystEngComm 2010, 12, 49. (c) Chen, L.; Xu, G. J.; Shao, K. Z.; Zhao, Y. H.; Yang, G. S.; Lan, Y. Q.; Wang, X. L.; Xu, H. B; Su, Z. M. CrystEngComm 2010, 12, 2157. (d) Long, L. S. CrystEngComm 2010, 12, 1354. (e) Qin, J. S.; Du, D. Y.; Li, S. L.; Lan, Y. Q.; Shao, K. Z.; Su, Z. M. CrystEngComm 2011, 13, 779. (f) Fang, H. C.; Zhu, J. Q.; Zhou, L. J.; Jia, H. Y.; Li, S. S.; Gong, X.; Li, S. B.; Cai, Y. P.; Thallapally, P. K.; Liu, J.; Exarhos, G. J. Cryst. Growth Des. 2010, 10, 3277. (g) Liu, D.; Ren, Z. G.; Li, H. X.; Chen, Y.; Wang, J.; Zhang, Y.; Lang, J. P. CrystEngComm 2010, 12, 1912. (h) Zheng, P. Q.; Ren, Y. P.; Long, L. S.; Huang, R. B.; Zheng, L. S. Inorg. Chem. 2005, 44, 1190. (i) Yang, H. X.; Gao, S. Y.; L€u, J.; Xu, B.; Lin, J. X.; Cao, R. Inorg. Chem. 2010, 49, 736. (j) Fang, S. M.; Zhang, Q.; Hu, M.; Sanudo, E. C.; Du, M.; Liu, C. S. Inorg. Chem. 2010, 49, 9617. (12) (a) Chen, Y.; Wang, Z. O.; Ren, Z. G.; Li, H. X.; Li, D. X.; Liu, D.; Zhang, Y.; Lang, J. P. Cryst. Growth Des. 2009, 9, 4963. (b) Mahata, P.; Prabu, M.; Natarajan, S. Inorg. Chem. 2008, 47, 8451. (13) (a) Bauer, S.; Stock, N. Angew. Chem., Int. Ed. 2007, 46, 6857. (b) Forster, P. M.; Burbank, A. R.; Livage, C.; F
erey, G.; Cheetham, A. K. Chem. Commun. 2004, 368. (c) Zhang, J.; Bu, X. H. Chem. Commun. 2008, 444. (d) Chen, J. X.; Tang, X. Y.; Chen, Y.; Zhang, W. H.; Li, L. L.; Yuan, R. X.; Zhang, Y.; Lang, J. P. Cryst. Growth Des. 2009, 9, 1461. (e) Tong, M. L.; Kitagawa, S.; Chang, H. C.; Ohba, M. Chem. Commun. 2004, 418. (f) Mahata, P.; Sundaresan, A.; Natarajan, S. Chem. Commun. 2007, 4471. (14) (a) Xiong, K. C.; Wu, M. Y.; Zhang, Q. F.; Wei, W.; Yang, M.; Jiang, F. L.; Hong, M. C. Chem. Commun. 2009, 1840. (b) Liu, C.; Luo, F.; Liao, W. P.; Li, D. Q.; Wang, X. F.; Dronskowski, R. Cryst. Growth Des. 2007, 7, 2282. (c) Bi, Y. F.; Liao, W. P.; Zhang, H. J. Cryst. Growth Des. 2008, 8, 3630. (d) Liu, Y. B.; Liao, W. P.; Bi, Y. F.; Wang, X. F.; Zhang, H. J. Cryst. Growth Des. 2009, 9, 5311. (e) Atwood, J. L.; Ness, T.; Nichols, P. J.; Raston, C. L. Cryst. Growth Des. 2002, 2, 171. (f) Atwood, J. L.; Barbour, L. J.; Ness, T. J.; Raston, C. L.; Raston, P. L. J. Am. Chem. Soc. 2001, 123, 7192. (g) Liu, Y.; Chen, K.; Guo, D. S.; Li, Q.; Song, H. B. Cryst. Growth Des. 2007, 7, 2601. (h) Guo, D. S.; Su, X.; Liu, Y. Cryst. Growth Des. 2008, 8, 3514. (i) Lazar, A.; Da Silva, E.; Navaza, A.; Barbeyb, C.; Coleman, A. W. Chem. Commun. 2004, 2162. (j) Danylyuk, 3487

dx.doi.org/10.1021/cg200308k |Cryst. Growth Des. 2011, 11, 3479–3488

Crystal Growth & Design

ARTICLE

O.; Le
sniewska, B.; Suwinska, K.; Matoussi, N.; Coleman, A. W. Cryst. Growth Des. 2010, 10, 4542. (k) Barbour, L. J.; Orr, G. W.; Atwood, J. L. Nature 1998, 393, 671. (15) (a) Bolte, M.; Thondorf, I.; B€ohmer, V.; Rudzevich, V.; Rudzevich, Y. CrystEngComm 2008, 10, 270. (b) Matheny, J. M.; Bosch, E.; Barnes, C. L. Cryst. Growth Des. 2007, 7, 984. (c) Tedesco, C.; Erra, L.; Immediata, I.; Gaeta, C.; Brunelli, M.; Merlini, M.; Meneghini, C.; Pattison, P.; Neri, P. Cryst. Growth Des. 2010, 10, 1527. (d) Dalgarno, S. J.; Raston, C. L. Dalton Trans. 2003, 287. (e) Dalgarno, S. J.; Hardie, M. J.; Raston, C. L. Cryst. Growth Des. 2004, 4, 227. (f) Ma, J. C.; Dougherty, D. A. Chem. Rev. 1997, 97, 1303. (g) Fischer, C.; Gruber, T.; Eissmann, D.; Seichter, W.; Weber, E. Cryst. Growth Des. 2011, 11, 1989. (h) Gutsche, C. D. Calixarenes
An Introduction; Monographs in Supramolecular Chemistry; Royal Society of Chemistry: Cambridge, U.K., 2008. (i) Asfari, Z., B€ohmer, V., Harrowfield, J., Vicens, J., Eds. Calixarenes 2001; Kluwer Academic Publishers: Dordrecht, the Netherlands, 2001. (j) Mandolini, L., Ungaro, R., Eds. Calixarene in Action; Imperial College Press: London, 2000. (k) Dalgarno, S. J.; Claudio-Bosque, K. M.; Warren, J. E.; Glass, T. E.; Atwood, J. L. Chem. Commun. 2008, 1410. (l) Maerz, A. K.; Thomas, H. M.; Power, N. P.; Deakyne, C. A.; Atwood, J. L. Chem. Commun. 2010, 46, 1235. (16) Morita, Y.; Agawa, T.; Nomura, E.; Taniguchi, H. J. Org. Chem. 1992, 57, 3658. (17) Sheldrick, G. M. SHELXS-97 and SHELXL-97, Program for X-ray Crystal Structure Solution; University of G€oettingen: Germany, 1997. (18) Ho, I. T.; Lee, G. H.; Chung, W. S. J. Org. Chem. 2007, 72, 2434. (19) (a) Nefedov, S. E.; Kozitsyna, N. Y.; Vargaftik, M. N.; Moiseev, I. I. Polyhedron 2009, 28, 172. (b) Panyushkin, V. T.; Bukov, N. N.; Abramov, D. E. Polyhedron 2003, 22, 271. (c) Ehlinger, N.; Lecocq, S.; Perrin, R.; Perrin, M. Supramol. Chem. 1993, 2, 77. (20) Spek, A. L. J. Appl. Crystallogr. 2003, 36, 7. (21) (a) Barja, B.; Aramendia, P.; Baggio, R.; Garland, M. T.; Pena, O.; Perec, M. Inorg. Chim. Acta 2003, 355, 183. (b) Chi, Y. X.; Niu, S .Y.; Wang, Z. L.; Jin, J. Eur. J. Inorg. Chem. 2008, 2336. (c) Yang, X. P.; Hahn, B. P.; Wong, W. K.; Jones, R. A.; Stevenson, K. J. Inorg. Chem. 2007, 46, 7050. (d) Chapelet-Arab, B.; Duvieubourg, L.; Nowogrocki, G.; Abraham, F.; Grandjean, S. J. Solid State Chem. 2006, 179, 4029. (e) Weng, D. F.; Zheng, X. J.; Jin, L. P. Eur. J. Inorg. Chem. 2006, 4184. (f) Yang, X. P.; Jones, R. A.; Oye, M. M.; Holmes, A. L.; Wong, W. K. Cryst. Growth Des. 2006, 6, 2122. (22) (a) Wang, P.; Ma, J. P.; Dong, Y. B. Chem. A. Eur. J. 2009, 15, 10432. (b) Dong, Y. B.; Wang, P.; Ma, J. P.; Zhao, X. X.; Wang, H. Y.; Tang, B.; Huang, R. Q. J. Am. Chem. Soc. 2007, 129, 4872. (23) Liu, L. L.; Wan, L. M.; Ren, Z. G.; Lang, J. P. Inorg. Chem. Commun. 2011, 14, 1069. (24) (a) Gispert, J. R., Eds. Coordination Chemistry; Wiley-VCH: New York, 2008. (b) Zhang, J. J.; Wojtas, L.; Larsen, R. W.; Eddaoudi, M.; Zaworotko, M. J. J. Am. Chem. Soc. 2009, 131, 17040.

3488

dx.doi.org/10.1021/cg200308k |Cryst. Growth Des. 2011, 11, 3479–3488