Novel layered lead(II) aminodiphosphonates with carboxylate-sulfonate and 1,3,5-benzenetricarboxylate ligands as pendant groups or intercalated species

Article abstract of DOI:10.1002/ejic.200300607

The hydrothermal reaction of lead(II) carbonate with 3-sulfobenzoic acid, 3-HO₃S-C₆H₄-CO₂H, and isopropylimino-bis(methylenephosphonic acid), (CH₃) ₂CHN(CH₂PO₃H₂)₂ (H ₄L¹), gave a new layered lead(II) carboxylate-phosphonate, Pb₇(S-O₃S-C₆H₄-CO ₂)(L¹)₃(H₂O)₂· 2H₂O (1), whereas the hydrothermal reaction of lead(II) carbonate with 1, 3,5-benzenetricarboxylic acid (H₃BTC) and N-cyclohexyUmino-bis(methylenephosphonic acid), C₆H ₁₁N(CH₂PO₃H₂)₂ (H ₄L²), afforded a layered complex, Pb₃(HL ²)(H₂L²)(H₂BTC)-(H ₂O)·H₃BTC·H₂O (2). The structure of complex 1 contains 〈010〈 lead(II) carboxylate-phosphonate hybrid layers, with the sulfonate group of the carboxylate-sulfonate ligand as the pendant group. In complex 2, the lead(II) ions are interconnected through bridging diphosphonate ligands, and results in the formation of a lead(II) diphosphonate slab, which are further interlinked via hydrogen bonds between non-coordinated phosphonate oxygen atoms to form a 〈001〈 layer. The doubly protonated H₂BTC anion is bidentately chelated to a lead(II) ion through a carboxylate group, whereas the neutral H₃BTC ligand is intercalated between two layers, forming hydrogen bonds with the non-coordinated carboxylate groups of the H₂BTC anion. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.

Full text of DOI:10.1002/ejic.200300607

FULL PAPER
Novel Layered Lead(II) Aminodiphosphonates with Carboxylate-Sulfonate and
1,3,5-Benzenetricarboxylate Ligands as Pendant Groups or Intercalated
Species
Shao-Ming Ying[a] and Jiang-Gao Mao*[a]
Keywords: Hydrothermal synthesis / Layered compounds / Carboxylates / Sulfonates
The hydrothermal reaction of lead(II) carbonate with 3-sul-
pendant group. In complex 2, the lead(II) ions are intercon-
fobenzoic acid, 3-HO3S−C6H4−CO2H, and isopropylimino-bis- nected through bridging diphosphonate ligands, and results
(methylenephosphonic
acid),
(CH3)2CHN(CH2PO3H2)2
in the formation of a lead(II) diphosphonate slab, which are
further interlinked via hydrogen bonds between non-coor-
dinated phosphonate oxygen atoms to form a Ͻ001Ͼ layer.
(H4L1), gave a new layered lead(II) carboxylate-phosphonate,
Pb7(3-O3S−C6H4−CO2)(L1)3(H2O)2·2H2O (1), whereas the hy-
drothermal reaction of lead(II) carbonate with 1, 3,5-benzene- The doubly protonated H2BTC anion is bidentately chelated
tricarboxylic acid (H3BTC) and N-cyclohexylimino-bis(me-
to a lead(II) ion through a carboxylate group, whereas the
neutral H3BTC ligand is intercalated between two layers,
forming hydrogen bonds with the non-coordinated
carboxylate groups of the H2BTC anion.
( Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim,
Germany, 2004)
thylenephosphonic acid), C6H11N(CH2PO3H2)2 (H4L2),
afforded
a
layered complex, Pb3(HL2)(H2L2)(H2BTC)-
(H2O)·H3BTC·H2O (2). The structure of complex 1 contains
Ͻ010Ͼ lead(II) carboxylate-phosphonate hybrid layers, with
the sulfonate group of the carboxylate-sulfonate ligand as the
Introduction
and a microporous zinc() complex of phosphonopropionic
acid and 1,3,5-benzene-tricarboxylic acid (H3BTC) has
been isolated, in which the tricarboxylate moiety remains
non-coordinated and is also severely disordered.[2] Recently,
we reported two novel porous lead() carboxylate-phos-
phonates in which both types of ligands act as multidentate
metal linkers.[10] We have initiated a research program in
order to study the intercalation chemistry of the layered
lead() diphosphonates with various types carboxylic acids
and sulfonic acids. Such hybrids may have good proton con-
ductivities, as well as ion-exchange properties, due to the
presence of protons with greater acidity. The hydrothermal
reaction of lead() carbonate with 3-sulfobenzoic acid, 3-
HO3SϪC6H4ϪCO2H, and isopropylimino-bis(methylene-
phosphonic acid), (CH3)2CHN(CH2PO3H2)2 (H4L1), gave
a new layered lead() carboxylate-phosphonate, Pb7(3-
O3SϪC6H4ϪCO2)(L1)3(H2O)2·2H2O (1), whereas the
hydrothermal reaction of lead() carbonate with 1, 3,5-ben-
zenetricarboxylic acid (H3BTC) and N-cyclohexylimino-
bis(methylenephosphonic acid), C6H11N(CH2PO3H2)2
Materials with open-framework and microporous struc-
tures are a class of very important compounds due to their
traditional applications in catalysis, separations, sorbents,
and ion exchange. Further, it is expected that these com-
pounds could be used as hybrid composite materials in elec-
tro-optical and sensing applications.[1,2] Studies of metal
phosphonates have shown that the use of bifunctional or
multifunctional anionic units, such as diphosphonates, ami-
nophosphonates or phosphonocarboxylates can lead to new
materials
with
microporous
or
open-framework
structures.[3Ϫ6] Recently, we have isolated a microporous
CdII complex with the N,NЈ-bis(phosphonomethyl)-1,10-di-
aza-18-crown ether.[7] Several porous ZrIV complexes with
aza-crown ether functionalized phosphonic acids have been
synthesized using phosphoric acid as the spacer.[8] The di-
rect use of two types of ligands in the preparation, such as
a phosphonic acid and a carboxylic acid, has been found to
be another effective method for the exploration of hybrid
open-frameworks; however, such reports are still rare.[2,9,10]
A 3-D open-framework tin() phosphonopropionate oxa-
late and a layered tin() methylphosphonate oxalate have
previously been reported by Cheetham and co-workers,[9]
(H4L2), afforded
a
layered complex, Pb3(HL2)-
(H2L2)(H2BTC)(H2O)·H3BTC·H2O (2). Herein, we report
on the syntheses, characterizations and crystal structures of
these compounds.
[a]
State Key Laboratory of Structural Chemistry, Fujian Institute
of Research on the Structure of Matter, Chinese Academy of
Sciences,
Results and Discussion
Fuzhou 350002, P. R. China
Fax: (internat.) ϩ86-591-3714946
E-mail: mjg@ms.fjirsm.ac.cn
The hydrothermal reaction of lead() carbonate with 3-
sulfobenzoic acid, 3-HO3SϪC6H4ϪCO2H, and isopro-
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Novel Layered Lead(II) Aminodiphosphonates
FULL PAPER
pylimino-bis(methylenephosphonic acid), (CH3)2CHN-
(CH2PO3H2)2 (H4L1), gave
carboxylatephosphonate,
a
new layered lead()
Pb7(3-O3SϪC6H4ϪCO2)(L1)3-
(H2O)2·2H2O (1), whereas the hydrothermal reaction of
lead() carbonate with 1, 1,3,5-benzenetricarboxylic acid
(H3BTC) and N-cyclohexylimino-bis(methylenephosphonic
acid), C6H11N(CH2PO3H2)2 (H4L2), afforded a layered
complex, Pb3(HL2)(H2L2)(H2BTC)(H2O)·H3BTC·H2O (2).
We believe that many more new inorganic-organic hybrid
materials will be developed using the synthetic technique of
mixing two different types of ligands.
Pb7(3-O3SϪC6H4ϪCO2)(L1)3(H2O)2·2H2O (1) is the first
structurally characterized metal phosphonate-sulfonate hy-
brid. It is composed of seven lead() ions, three fully depro-
tonated L1 ligands, one 3-O3SϪC6H4ϪCO2 dianion, two
aqua ligands and two lattice water molecules. As shown in
Figure 1, Pb1 is six-coordinate and is bonded to a tridentate
chelating L1 anion (N3, O52 and O62), two phosphonate
oxygen atoms from two other L1 anions (O13 and O12), as
well as to a carboxylate oxygen atom from a carboxylate-
sulfonate ligand. Pb1 exhibits a distorted octahedral coordi-
nation geometry. Pb2 is four-coordinate and is bonded to
three phosphonate oxygen atoms from three L1 anions and
one carboxylate oxygen atom from a sulfonate ligand. The
coordination geometry around Pb2 can be described as a
ψ-PbO4 trigonal bipyramid, with the fifth coordination site
occupied by the lone pair of electrons from the PbII ion.
Pb3 is five-coordinate and is bonded to a tridentate chelat-
ing L1 anion (N2, O32, O42) and two phosphonate oxygen
atoms from two other L1 anions; it exhibits a ψ-PbO5 octa-
hedral geometry, with the sixth coordination site occupied
by the lone pair of electrons from the PbII ion. Pb4, Pb5
and Pb6 have a coordination geometry similar to that exhi-
bited by Pb3; they are all five-coordinate and are bonded
to a bidentate chelating L1 ligand (O51 and O52 for Pb4;
O31 and O43 for Pb5; O52 and O63 for Pb6) and three
phosphonate oxygen atoms from three other L1 anions. Pb7
is four-coordinate and is bonded to two phosphonate oxy-
gen atoms from two L1 anions and two aqua ligands, and
exhibits a ψ-PbO4 trigonal bipyramidal geometry with the
fifth coordination site occupied by the lone pair of electrons
Figure 2. The coordination modes of L2 and sulfo-carboxylate li-
gands in complex 1
Figure 3. View of the structure of complex 1 down the c-axis. The
CϪPO3 and CϪSO3 tetrahedra are shaded in light and dark gray,
respectively. Pb, N, O and C atoms are represented by open,
octanded, crossed and black circles, respectively.
Figure 1. The coordination geometries around the lead(II) ions in complex 1
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Eur. J. Inorg. Chem. 2004, 1270Ϫ1276
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˚
Table 1. Bond lengths [A] and angles [°] for complex 1 (symmetry transformations used to generate equivalent atoms: #1 Ϫ x ϩ 2,
Ϫy ϩ 2, Ϫz; #2 Ϫ x ϩ 2, Ϫy ϩ 2, Ϫz ϩ 1; #3 Ϫ x ϩ 1, Ϫy ϩ 2, Ϫz; #4 x Ϫ 1, y, z; #5 Ϫ x ϩ 1, Ϫy ϩ 2, Ϫz ϩ 1; #6 x, 1 ϩ y, z)
Pb(1)ϪO(62)
Pb(1)ϪO(13)
Pb(1)ϪN(3)
2.39(2)
Pb(1)ϪO(52)
Pb(1)ϪO(12)#1
Pb(1)ϪO(1)
Pb(2)ϪO(22)
Pb(2)ϪO(2)
Pb(3)ϪO(42)
Pb(3)ϪN(2)
Pb(4)ϪO(53)#3
Pb(4)ϪO(12)#1
Pb(4)ϪO(52)
Pb(5)ϪO(23)
Pb(5)ϪO(21)#5
Pb(6)ϪO(63)
Pb(6)ϪO(13)
Pb(6)ϪO(52)
Pb(7)ϪO(41)
Pb(7)ϪO(2 W)
2.450(15)
2.619(15)
2.712(15)
2.512(16)
2.647(16)
2.369(15)
2.618(17)
2.409(17)
2.530(15)
2.747(18)
2.471(15)
2.567(14)
2.30(2)
2.495(15)
2.643(19)
2.372(16)
2.556(16)
2.339(15)
2.577(15)
2.651(14)
2.427(16)
2.574(18)
2.391(16)
2.537(15)
2.664(15)
2.621(16)
2.680(17)
2.287(18)
2.56(2)
Pb(2)ϪO(33)
Pb(2)ϪO(42)#2
Pb(3)ϪO(32)
Pb(3)ϪO(32)#2
Pb(3)ϪO(22)
Pb(4)ϪO(11)
Pb(4)ϪO(51)
Pb(5)ϪO(43)#4
Pb(5)ϪO(31)#4
Pb(5)ϪO(43)#2
Pb(6)ϪO(23)
Pb(6)ϪO(51)#3
Pb(7)ϪO(61)#2
Pb(7)ϪO(1 W)
2.669(14)
2.710(16)
2.335(16)
2.65(3)
Hydrogen bonds
O(3 W)···O(1 W)
2.80(3)
2.80(3)
92.5(7)
74.0(5)
73.0(5)
72.4(6)
130.8(5)
74.8(6)
84.4(5)
121.1(5)
103.8(5)
78.9(6)
75.9(6)
80.4(5)
71.2(5)
142.3(5)
151.6(5)
89.0(5)
150.8(6)
83.0(6)
87.6(6)
76.1(5)
55.2(5)
82.9(5)
76.8(5)
126.7(5)
76.7(5)
74.2(5)
95.0(7)
109.3(8)
136.6(5)
137.5(5)
83.0(5)
83.1(7)
99.4(10)
167.4(10)
O(4 W)···O(1 W)
2.85(5)
O(4 W)···O(4)#6
O(62)ϪPb(1)ϪO(52)
O(52)ϪPb(1)ϪO(13)
O(52)ϪPb(1)ϪO(12)#1
O(62)ϪPb(1)ϪN(3)
O(13)ϪPb(1)ϪN(3)
O(62)ϪPb(1)ϪO(1)
O(13)ϪPb(1)ϪO(1)
N(3)ϪPb(1)ϪO(1)
O(33)ϪPb(2)ϪO(42)#2
O(33)ϪPb(2)ϪO(2)
O(42)#2ϪPb(2)ϪO(2)
O(32)ϪPb(3)ϪO(32)#2
O(32)ϪPb(3)ϪN(2)
O(62)ϪPb(1)ϪO(13)
O(62)ϪPb(1)ϪO(12)#1
O(13)ϪPb(1)ϪO(12)#1
O(52)ϪPb(1)ϪN(3)
O(12)#1ϪPb(1)ϪN(3)
O(52)ϪPb(1)ϪO(1)
O(12)#1ϪPb(1)ϪO(1)
O(33)ϪPb(2)ϪO(22)
O(22)ϪPb(2)ϪO(42)#2
O(22)ϪPb(2)ϪO(2)
O(32)ϪPb(3)ϪO(42)
O(42)ϪPb(3)ϪO(32)#2
O(42)ϪPb(3)ϪN(2)
O(32)ϪPb(3)ϪO(22)
O(32)#2ϪPb(3)ϪO(22)
O(53)#3ϪPb(4)ϪO(11)
O(11)ϪPb(4)ϪO(12)#1
O(11)ϪPb(4)ϪO(51)
O(53)#3ϪPb(4)ϪO(52)
O(12)#1ϪPb(4)ϪO(52)
O(43)#4ϪPb(5)ϪO(23)
O(23)ϪPb(5)ϪO(31)#4
O(23)ϪPb(5)ϪO(21)#5
O(43)#4ϪPb(5)ϪO(43)#2
O(31)#4ϪPb(5)ϪO(43)#2
O(63)ϪPb(6)ϪO(23)
O(23)ϪPb(6)ϪO(13)
O(23)ϪPb(6)ϪO(51)#3
O(63)ϪPb(6)ϪO(52)
O(13)ϪPb(6)ϪO(52)
O(61)#2ϪPb(7)ϪO(41)
O(41)ϪPb(7)ϪO(1 W)
O(41)ϪPb(7)ϪO(2 W)
76.1(7)
165.2(7)
96.2(5)
70.8(6)
104.9(6)
157.2(5)
117.5(5)
80.1(5)
84.7(5)
146.9(5)
79.1(6)
77.9(5)
72.9(5)
74.3(5)
106.9(4)
81.8(7)
83.5(6)
130.5(6)
82.4(6)
69.7(5)
87.2(5)
76.5(5)
148.7(5)
79.9(5)
148.7(4)
82.7(7)
77.3(5)
139.4(6)
78.1(7)
67.1(5)
80.2(6)
84.5(7)
83.8(9)
O(32)#2ϪPb(3)ϪN(2)
O(42)ϪPb(3)ϪO(22)
N(2)ϪPb(3)ϪO(22)
O(53)#3ϪPb(4)ϪO(12)#1
O(53)#3ϪPb(4)ϪO(51)
O(12)#1ϪPb(4)ϪO(51)
O(11)ϪPb(4)ϪO(52)
O(51)ϪPb(4)ϪO(52)
O(43)#4ϪPb(5)ϪO(31)#4
O(43)#4ϪPb(5)ϪO(21)#5
O(31)#4ϪPb(5)ϪO(21)#5
O(23)ϪPb(5)ϪO(43)#2
O(21)#5ϪPb(5)ϪO(43)#2
O(63)ϪPb(6)ϪO(13)
O(63)ϪPb(6)ϪO(51)#3
O(13)ϪPb(6)ϪO(51)#3
O(23)ϪPb(6)ϪO(52)
O(51)#3ϪPb(6)ϪO(52)
O(61)#2ϪPb(7)ϪO(1 W)
O(61)#2ϪPb(7)ϪO(2 W)
O(1 W)ϪPb(7)ϪO(2 W)
from the PbII ion. The PbϪO distances are in the range bidentate fashion, and also forms bridges with eight other
2.287(18) to 2.747(18) A, and the PbϪN distances range PbII ions. Its amine group remains non-coordinated and
˚
˚
from 2.618(17) to 2.643(19) A; these distances are similar four phosphonate oxygen atoms act as µ2 metal linkers. The
to those reported for other PbII aminodiphos- diphosphonate anion that contains P3 and P4 chelates Pb3
phonates.[10Ϫ12] The three L1 anions in complex 1 adopt in a tridentate manner (N2, O32 and O42), chelates Pb5 in
three different types of coordination modes (see Figure 2). a bidentate fashion (O31, O43), and forms bridges with five
The L1 anion that contains P1 and P2 chelates Pb6 in a other lead() ions. The three phosphonate oxygen atoms are
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Eur. J. Inorg. Chem. 2004, 1270Ϫ1276

Novel Layered Lead(II) Aminodiphosphonates
FULL PAPER
bidentate. The third L1 anion is bonded to Pb1 in a triden- atoms from three diphosphonate ligands (1 H2L2 and 2
tate fashion, chelates Pb4 and Pb6 bidentately and also HL2) and an aqua ligand. It has a ψ-PbO5 octahedral ge-
forms bridges with three other lead() ions. O52 acts as a ometry that is similar to that of Pb2. The PbϪO distances
˚
µ3 metal linker, and only O51 is a µ2 bridging group. This range from 2.407(12) to 2.767(13) A; these distances are
kind of coordination mode has not been reported before. similar to those in complex 1 and those observed in other
The carboxylate-sulfonate anion is bidentate, forming lead() phosphonates,[10Ϫ12] as well as to those reported for
bridges with two PbII ions through the carboxylate group. the lead() complex with H3BTC.[13]
The sulfonate group remains non-coordinated. Based on
The HL2 anion that contains P2 and P3 is heptadentate;
the requirements of charge balance, both types of ligands
it chelates Pb1 in a bidentate manner (O21 and O32) and
have been completely deprotonated.
forms bridges with five other lead() ions. The O23 and
The interconnection of the above PbII polyhedra through
O32 atoms are bidentate metal linkers. Both phosphonate
the diphosphonate L1 anions, as well as through the car-
groups are fully deprotonated, but the amine group remains
boxylate-sulfonate ligands, results in a Ͻ010Ͼ hybrid layer.
protonated. The H2L2 anion containing P4 and P5 is tetra-
˚
The interlayer distance is approximately 14.9 A. The sulfon-
dentate; it chelates Pb3 in a bidentate fashion (O41 and
ate group acts as a pendant group, hanging between two
layers (Figure 3). The lattice water molecules are also lo-
O53) and also connects with two other PbII ions. The O42
atom is a bidentate metal linker. The P4 and P5 phosphon-
cated in the middle of the interlayer space, forming hydro-
ate groups are tridentate and unidentate, respectively. Based
gen bonds with the non-coordinated sulfonate groups, as
on the PϪO distance and the charge balance, the P5 phos-
well as with the aqua ligands ( Table 1). The O(4 W)···O(4)
phonate group should be 1H-protonated, so does the amine
(symmetry code: x, 1 ϩ y, z) contact distance is only 2.60(4)
group, hence the doubly protonated diphosphonate anion
carries two negative charges. The H2BTC anion in complex
2 is bidentately chelated to Pb2 (O5 and O6) and the other
two carboxylate groups remain non-coordinated, while all
three carboxylate groups of the neutral H3BTC ligand in
complex 2 are non-coordinated (Figure 4). This is unlike
the situation in porous lead() phosphonate-carboxylates in
which all three carboxylate groups are involved in metal co-
ordination.[10]
˚
A, indicating that the hydrogen bond between the lattice
water molecule and the sulfonate group is very strong.
Pb3(HL2)(H2L2)(H2BTC)(H2O)·H3BTC·H2O (2) also has
a layered structure and contains 1,3,5-benzene-tricarboxyl-
ate ligands that behave both as a pendant group and as
an intercalated species. As shown in Figure 4, Pb1 is four-
coordinate and is bonded to four phosphonate oxygen
atoms from three diphosphonate ligands (1 H2L2 and 2
HL2). Its coordination geometry can be described as a ψ-
PbO4 square pyramid with the fifth coordination site occu-
The interconnecting lead() ions, via bridging amino di-
pied by the lone pair of electrons. Pb2 is five-coordinate phosphonate ligands, leads to the formation of a slab along
and is bonded to a bidentate carboxylate group of the the a-axis. Such slabs are further interlinked via strong hy-
H2BTC anion and three phosphonate oxygen atoms from drogen bonds between the non-coordinated phosphonate
three diphosphonate ligands (1 H2L2 and 2 HL2). Its coor- oxygen atoms to form a Ͻ001Ͼ layer (Figure 5). The
dination geometry can be described as a ψ-PbO5 octa- O(33)···O(52) distance (symmetry code: Ϫx, y Ϫ 1, Ϫz) is
˚
hedron with the sixth site occupied by the lone pair of elec- 2.509(17) A (Table 2). The non-coordinated dicarboxylate
˚
trons. The Pb(2)ϪO(6) bond of 2.766(10) A is significantly moiety of H2BTC is orientated towards the interlayer space,
˚
longer than the Pb(2)ϪO(5) bond [2.584(13) A]. Pb3 is five- and is able to form hydrogen bonds with the carboxylate
coordinate and is bonded to four phosphonate oxygen groups of the neutral H3BTC ligand (Table 2, Figure 6).
Figure 4. The asymmetric unit of complex 2. The elongated Pb-O bond is represented by an open line; hydrogen bond is drawn as a
dotted line; symmetry codes for the generated atoms: a) Ϫx, Ϫy, Ϫz; b) x ϩ 1, y, z; c) Ϫ1 ϩ x, y, z
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Such hydrogen bonding creates a six-membered ring that complex 1, mainly due to the intercalation of the H3BTC
consists of two carboxylate groups, one from H3BTC and molecules.
one from H2BTC (Figure 6). The aqua ligands are located
at the cavities within the 2-D layer, and form hydrogen
bonds with the non-coordinated phosphonate oxygen
atoms, as well as with the amine groups (Table 2). The inter-
˚
layer space of about 21.4 A is much larger than that of
Figure 6. View of the structure of complex 2 down the a-axis; the
CϪPO3 tetrahedra are shaded in gray, and Pb, N, O and C atoms
are represented by open, octanded, crossed and black circles,
respectively; hydrogen bonds are drawn as dotted lines.
The XRD powder patterns for complexes 1 and 2 were
collected on a Philips XЈPert-MPD diffractometer using
graphite-monochromated Cu-Kα radiation in the angular
range 2θ ϭ 5Ϫ70°. The powder patterns of 1 and 2 match
those calculated from their single-crystal structure data,
thus both compounds exist as a single phase.
The IR spectra of complexes 1 and 2 show the asymmet-
ric and symmetric vibrations of the carboxyl group at 1531
Figure 5. A Ͻ001Ͼ layer formed by the interconnection of lead()
ion by bridging diphosphonate ligands in complex 2; the pendant
H2BTC anions have been omitted for clarity; the CϪPO3 tetra-
hedra are shaded in gray, and Pb, N, O and C atoms are represented
by open, octanded, crossed and black circles, respectively
˚
Table 2. Bond lengths [A] and angles [°] for complex 2 (symmetry transformations used to generate equivalent atoms: #1 Ϫx, Ϫy, Ϫz;
#2 x ϩ 1, y, z; #3 x Ϫ 1, Ϫ1 Ϫ y, Ϫz; #4 x Ϫ 1, y, z; #5 x, y, z Ϫ 1; #6 x Ϫ 1, y Ϫ 1, z Ϫ 1; #7 Ϫx Ϫ 1, Ϫy, Ϫz)
Pb(1)ϪO(21)
Pb(1)ϪO(32)
Pb(2)ϪO(23)#1
Pb(2)ϪO(5)
Pb(3)ϪO(41)#2
Pb(3)ϪO(53)#2
Pb(3)ϪO(32)#2
2.429(12)
2.605(12)
2.418(11)
2.584(13)
2.316(12)
2.407(12)
2.744(11)
Pb(1)ϪO(42)
Pb(1)ϪO(23)#1
Pb(2)ϪO(42)
Pb(2)ϪO(22)
Pb(3)ϪO(1 W)
Pb(3)ϪO(31)
2.495(13)
2.688(11)
2.517(13)
2.628(12)
2.345(13)
2.687(11)
Hydrogen bonds
O(1 W)···O(51)
2.601(22)
2.509(17)
2.735(17)
2.695(18)
2.613(18)
2.613(19)
99.6(5)
77.7(4)
70.4(4)
74.6(4)
74.0(4)
75.6(4)
77.0(5)
74.0(5)
76.3(5)
89.3(4)
86.3(4)
O(1 W)···O(33)#3
O(2 W)···N(2)
O(2 W)···O(22)
O(2)···O(8)#5
2.803(19)
2.858(19)
2.769(16)
2.625(19)
2.657(19)
O(33)···O(52)#3
O(2 W)···O(31)#4
O(1)···O(7)#5
O(3)···O(9)#6
O(4)···O(10)#6
O(11)···O(43)#7
O(21)ϪPb(1)ϪO(42)
O(42)ϪPb(1)ϪO(32)
O(42)ϪPb(1)ϪO(23)#1
O(23)#1ϪPb(2)ϪO(42)
O(42)ϪPb(2)ϪO(5)
O(42)ϪPb(2)ϪO(22)
O(41)#2ϪPb(3)ϪO(1 W)
O(1 W)ϪPb(3)ϪO(53)#2
O(1 W)ϪPb(3)ϪO(31)
O(41)#2ϪPb(3)ϪO(32)#2
O(53)#2ϪPb(3)ϪO(32)#2
O(21)ϪPb(1)ϪO(32)
74.9(4)
74.7(4)
130.8(3)
82.8(4)
82.2(4)
148.7(4)
80.5(4)
71.4(4)
142.8(4)
157.5(5)
116.5(3)
O(21)ϪPb(1)ϪO(23)#1
O(32)ϪPb(1)ϪO(23)#1
O(23)#1ϪPb(2)ϪO(5)
O(23)#1ϪPb(2)ϪO(22)
O(5)ϪPb(2)ϪO(22)
O(41)#2ϪPb(3)ϪO(53)#2
O(41)#2ϪPb(3)ϪO(31)
O(53)#2ϪPb(3)ϪO(31)
O(1 W)ϪPb(3)ϪO(32)#2
O(31)ϪPb(3)ϪO(32)#2
1274
 2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
Eur. J. Inorg. Chem. 2004, 1270Ϫ1276

Novel Layered Lead(II) Aminodiphosphonates
FULL PAPER
and 1419 cmϪ1 for complex 1, and 1576 and 1454 cmϪ1 for
complex 2, respectively. The differences in νas(COO) and
νs(COO) are much larger than 95 cmϪ1 in both complexes,
indicating the bidentate coordination mode for the car-
boxylate groups.[14] Complex 2 also exhibits a strong ab-
sorption band at 1722 cmϪ1 assigned to the non-coordinat-
ing carboxylate groups (COOH). The vibrations of the pho-
sphonic group groups can be seen in the region 900Ϫ1100
Experimental Section
Materials and Methods: All chemicals were obtained from commer-
cial sources and used without further purification. Elemental
analyses were performed on a Vario EL III elemental analyzer.
Thermogravimetric analyses were carried out with
SBTA851 unit at a heating rate of 15 °C/ min under a nitrogen
a TGA/
atmosphere. IR spectra were recorded on a Magna 750 FT-IR spec-
trometer as KBr pellets in the 4000Ϫ400 cmϪ1 range. H and 31P
1
cm .
Ϫ1 [7] The broad bands at 3406 cmϪ1 (for complex 1) and
NMR spectra were recorded on a Varian Unity 500 NMR in D2O.
H3PO4 (85%) was used as 31P standard reference. The XRD powder
patterns were collected on a Philips XЈPert-MPD diffractometer
using graphite-monochromated Cu-Kα radiation in the angular
range 2θ ϭ 5Ϫ70° with a step size of 0.02° and a counting time of
3 seconds per step.
3428 cmϪ1 (for complex 2) indicate the presence of the
water molecules in both compounds. Those frequencies
which are characteristic of the fundamental and split
νas(SϪO) stretching modes for complex 1 appear in the
range 1200Ϫ1000 cmϪ1
.
The TGA curves of complex 1 exhibit two steps corre-
sponding to weight losses. The first step indicates the loss
of two lattice water molecules and two aqua ligands, which
starts at 55 °C and ends at 210 °C. The observed weight
loss of 2.8% is in good agreement with the theoretical
weight loss (2.94%). The second weight loss step starts at
375 °C and continues up to 800 °C, and indicates the loss of
the aminodiphosphonate and carboxylate-sulfonate ligands.
The final products are Pb2P2O7 and PbSO4 (in a molar ra-
tio of about 3:1), based on the X-ray power pattern. The
total weight loss of 14.2% is similar to that calculated
(15.65%). The TGA diagram for complex 2 reveals three
main steps corresponding to weight losses. The first step
involves the loss of the lattice water molecule and the aqua
ligand, which starts at about 90 °C and ends at about 282
°C. The observed weight loss of 2.4% is in good agreement
with the calculated value (2.2%). The second step, which
covers a temperature range from 282 °C to 345 °C, corre-
sponds to the loss of intercalated H3BTC. The third step
starts at 345 °C and ends at 710 °C, and involves two over-
lapping processes: the loss of one water molecule formed by
the condensation of the hydrogen phosphonate groups, and
the loss of the diphosphonate ligand and the H2BTC anion.
The final products are Pb2P2O7 and Pb(PO3)2 (in a molar
ratio of 1:1), based on the XRD powder pattern. The total
weight loss is 41.3% is similar to that calculated (42.1%).
Preparation of H4L1 and H4L2: H4L1 and H4L2 were prepared by
a Mannich type reaction according to procedures described pre-
viously.[11]
Isopropylamine (100 mmol, 5.911 g) was mixed with hydrochloric
acid (16.0 cm3), deionized water (20 mL) and phosphorous acid
(400 mmol, 32.8 g). The mixture was allowed to reflux at 120 °C
for 1 h, paraformaldehyde (300 mmol, 9 g) was then added in small
portions over a period of 1 h, and the mixture was refluxed for one
additional hour. Removal of solvents afforded 16.8 g of a white
powder of H4L1 (yield 68.1%). Its purity was confirmed by NMR
spectroscopic measurements and elemental analysis. 31P NMR
spectroscopy shows a single peak at 9.50 ppm. 1H NMR: δ ϭ 1.37
(CH3, d, 6 H, JHϪH ϭ 5.5 Hz), 3.57 (NϪCH2ϪPO3, d, 4 H, JHϪP ϭ
12.5 Hz), 4.16 (Me2ϪCHϪN, sept., 1 H) ppm. Elemental analysis
for H4L1, C5H15NO6P2 (247.12): calcd. C 24.86, H 6.62, N 4.88;
found C 24.29, H 6.07, N 5.67.
H4L2 was obtained in a yield of 77.5% by a Mannich type reaction
using cyclohexylamine (100 mmol, 9.92 g), hydrochloric acid (16.0
cm3), deionized water (20.0 mL), phosphorous acid (400 mmol,
32.8 g) and paraformaldehyde (300 mmol, 9.0 g), in a similar
method to that of H4L1. 31P NMR spectroscopy shows a single
peak at 8.75 ppm. 1H NMR: δ ϭ 1.16, 1.36, 1.67, 1.91 and 2.06
(for five CH2Ϫ groups of cyclohexyl, d), 1.51 (CH- of cyclohexyl, t,
1 H), 3.51 (NϪCH2ϪPO3, d, 4 H, JH,P ϭ 13.0 Hz) ppm. Elemental
analysis for H4L2, C8H19NO6P2 (288.54): calcd. C 33.24, H 6.81,
N 4.59; found C 33.45, H 6.62, N 5.33.
Pb7(3-O3SϪC6H4؊CO2)(L1)3(H2O)2·2H2O (1) and Pb3(HL2)-
(H2L2)(H2BTC)(H2O)·H3BTC·H2O (2):
A mixture of PbCO3
(1.0 mmol, 0.267 g), H4L1 (0.5 mmol, 0.124 g), 3-sulfobenzoic acid
monosodium salt (0.5 mmol, 0.112 g) and deionized water (10 mL)
was sealed into a bomb equipped with a Teflon liner (20 mL), and
then heated at 180 °C for 5 days. Colorless prismatic crystals of
complex 1 were recovered in ca. 71% yield based on Pb. Elemental
analysis for 1, C22H45N3O27P6Pb7S (2451.82): calcd. C 10.67, H
1.38, N 1.82; found C 10.77, H 1.84, N 1.71%. IR data (KBr,
cmϪ1): ν˜ ϭ 3406 (s), 2962 (m), 2933 (m), 2875 (m), 2798 (m), 2407
(m), 1732 (m), 1651 (m), 1587 (m), 1531 (s), 1419 (s), 1383 (s), 1302
(m), 1200 (m), 1084 (vs), 1032 (vs), 966 (vs), 839 (m), 752 (m), 679
(m), 588 (s), 557 (s), 507 (m), 480 (m).
Conclusion
In summary, two novel layered lead() carboxylate-phos-
phonate hybrids were obtained by the hydrothermal reac-
tions of lead() carbonate with amino-diphosphonic acid
and 3-sulfobenzoic acid (or, 1,3,5-benzenetricarboxylic
acid). In both compounds, the 2-D inorganic-organic layer
is formed by the lead() ions that are interconnected
through the diphosphonate ligands. The sulfonate group of
the carboxylate-sulfonate ligand in complex 1 acts as a pen-
dant group between the 2-D layers, whereas the 1,3,5-ben-
zenetricarboxylate ligands in complex 2 act both as a pen-
dant ligand and as the intercalated species between two me-
tal-diphosphonate layers. It is believed that a wide range of
novel open-frameworks and microporous materials can be
developed using this ligand-hybrid technique.
A
mixture of PbCO3 (1.0 mmol, 0.267 g), H4L2 (0.5 mmol,
0.144 g), 1,3,5-benzenetricarboxylic acid (0.5 mmol, 0.105 g) and
deionized water (10 mL) was sealed into a bomb equipped with a
Teflon liner (20 mL), and then heated at 180 °C for 5 days. Pris-
matic colorless crystals of complex 2 were recovered in ca. 60%
yield based on Pb. Elemental analysis for 2, C34H48N2O26P4Pb3
Eur. J. Inorg. Chem. 2004, 1270Ϫ1276
www.eurjic.org
 2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
1275

S.-M. Ying, J.-G. Mao
FULL PAPER
(1646.19): calcd. C 23.93, H 2.42, N 1.62; found C 24.79, H 2.92, charge at www.ccdc.cam.ac.uk/conts/retrieving.html [or from the
N 1.70%. IR data (KBr, cmϪ1): ν˜ ϭ 3428 (s), 3021 (s), 2979 (s), Cambridge Crystallographic Data Centre, 12 Union Road, Cam-
2940 (s), 2862 (s), 2648 (s), 2542 (s), 1878 (m), 1722 (vs), 1614 (s), bridge CB2 1EZ, UK; Fax: (internat.) ϩ44-1223-336-033; E-mail:
1576 (s), 1454 (s), 1381 (s), 1281 (vs), 1111 (vs), 1051 (vs), 987 (s), deposit@ccdc.cam.ac.uk].
933 (s), 777 (m), 744 (s), 692 (s), 621 (m), 526 (m), 442 (m).
Acknowledgments
This work was supported by the National Natural Science
Foundation of China (No. 20371047), the Introduction of Overseas
Elitists Program by the Chinese Academy of Sciences and the
Scientific Research Foundation for the Returned Overseas Chinese
Scholars, State Education Ministry.
Crystal Structure Determination: Single crystals of complexes 1 and
2 were mounted on a Siemens Smart CCD diffractometer equipped
˚
with a graphite-monochromated Mo-Kα radiation (λ ϭ 0.71073 A).
Intensity data were collected by the narrow frame method at 293 K.
The data sets were corrected for Lorentz polarization, as well as
for absorption, by ψ scan technique. Both structures were solved
by direct methods and refined by full-matrix least-squares fitting
on F2 by SHELX-97.[15] All non-hydrogen atoms, except for N(2),
C(2), C(3), C(14), C(15), C(22) and C(23) in complex 1, and C(23)
in complex 2, were refined with anisotropic thermal parameters.
Those atoms refined with isotropic thermal parameters were non-
positive if refined anisotropically; this was caused by the problem
resulting from correcting the absorption due to the presence of very
[1]
A. K. Cheetham, G. Ferey, T. Loiseau, Angew. Chem. Int. Ed.
1999, 38, 3268Ϫ3292.
[2]
J. Zhu, X. Bu, P. Feng, G. D. Stucky, J. Am. Chem. Soc. 2000,
122, 11563Ϫ11564.
A. Distler, L. Lohse, S. C. Sevov, J. Chem. Soc., Dalton Trans.
[3]
1999, 1805Ϫ1812; V. Soghomonian, Q. Chen, R. C. Haush-
alter, J. Zubieta, Angew. Chem. Int. Ed. Engl. 1995, 34,
223Ϫ226.
heavy Pb atoms. The final difference Fourier maps showed feature-
Ϫ3
˚
˚
[4]
less residual peaks of 3.16 e·A (for complex 1, 0.91 A from Pb(2)
S. Drumel, P. Janvier, D. Deniaud, B. Bujoli, J. Chem. Soc.,
Ϫ3
˚
˚
atom) and 3.56 e A (for complex 2, 1.02 A from Pb(1) atom),
respectively. All hydrogen atoms were located at geometrically cal-
culated positions. The hydrogen atoms for the water molecules were
not included in the refinements. The large standard deviations for
the bond lengths in complex 1 are due to the poor quality of the
single crystals, which is very common for metal phosphonates; ef-
forts were made to isolate better quality crystals, however they were
unsuccessful. Crystallographic data and structural refinements are
summarized in Table 3. Important bond lengths and angles are
listed in Tables 1 and 2 for complexes 1 and 2, respectively.
Chem. Commun. 1995, 1051Ϫ1052; U. Costantino, M. Nocch-
etti, R. Vivani, J. Am. Chem. Soc. 2002, 124, 8428Ϫ8434; S. O.
H. Gutschke, D. J. Price, A. K. Powell, P. T. Wood, Angew.
Chem. Int. Ed. 1999, 38, 1088Ϫ1090; E. Galdecka, Z. Galdecki,
P. Gawryszewska, J. Legendziewicz, New J. Chem. 2000, 24,
387Ϫ391; L.-M. Zheng, P. Yin, X.-Q. Xin, Inorg. Chem. 2002,
41, 4084Ϫ4086.
[5]
N. Stock, S. A. Frey, G. D. Stucky, A. K. Cheetham, J. Chem.
Soc., Dalton Trans. 2000, 4292Ϫ4296; S. Ayyappan, G. D.
Delgado, A. K. Cheetham, G. Ferey, C. N. R. Rao, J. Chem.
Soc., Dalton Trans. 1999, 2905Ϫ2907; F. Fredoueil, M. Evain,
D. Massiot, M. Bujoli-Doeuff, P. Janvier, A. Clearfield, B. Bu-
joli, J. Chem. Soc., Dalton Trans. 2002, 1508Ϫ1512; S. Drumel,
M. Bujolidoeuff, P. Janvier, B. Bujoli, New J. Chem. 1995, 19,
239Ϫ242.
Table 3. Crystal data and structure refinement for complexes 1
and 2
[6]
(R1 ϭ Fo Ϫ Fc /Fo, wR2 ϭ {w[(Fo)2 Ϫ (Fc)2]2/w[(Fo)2]2}1/2
)
A. Distler, S. C. Sevov, Chem. Commun. 1998, 959Ϫ960; S. J.
Hartman, E. Todorov, C. Cruz, S. C. Sevov, Chem. Commun.
2000, 1213Ϫ1214; J.-G. Mao, Z. Wang, A. Clearfield, Inorg.
Chem. 2002, 41, 6106Ϫ6111; R. Vivani, U. Costantino, M.
Nocchetti, J. Mater. Chem. 2002, 12, 3254Ϫ3260.
Compound
1
2
Empirical formula
Molecular mass
Crystal system
Space group
C22H45N3O27P6Pb7S
2451.82
triclinic
C34H48N2O26P4Pb3
1646.19
triclinic
[7]
J.-G. Mao, Z. Wang, A. Clearfield, Inorg. Chem. 2002, 41,
3713Ϫ3720.
[8]
B. Zhang, A. Clearfield, J. Am. Chem. Soc. 1997, 119,
¯
¯
P1 (No.2)
P1 (No. 2)
2751Ϫ2752; A. Clearfield, D. M. Poojary, B. Zhang, B. Zhao,
A. Derecskei-Kovacs, Chem. Mater. 2000, 12, 2745Ϫ2752.
˚
a (A)
10.1796(4)
14.9014(6)
16.4192(6)
80.314(1)
77.032(1)
85.037(1)
2389.43(16)
2
3.408
24.902
2188
12523
8397 (Rint ϭ 0.081)
6427
560
1.083
0.0634, 0.1459
0.0925, 0.1656
7.1392(1)
15.5844(1)
21.3980(1)
105.658(1)
90.757(1)
96.214(1)
2276.65(4)
2
2.401
11.301
1560
11815
7925 (Rint ϭ 0.0495)
6850
618
1.195
0.0627, 0.1532
0.0746, 0.1600
˚
b (A)
[9]
N. Stock, G. D. Stucky, A. K. Cheetham, Chem. Commun.
˚
c (A)
2000, 2277Ϫ2278; B. Adair, S. Natarajan, A. K. Cheetham, J.
α/°
β/°
γ/°
Mater. Chem. 1998, 8, 1477Ϫ1479.
[10]
J.-L. Song, J.-G. Mao, Y.-Q. Sun, A. Clearfield, Eur. J. Inorg.
Chem., 2003, 4218.
J.-G. Mao, Z. Wang, A. Clearfield, Inorg. Chem. 2002, 41,
2334Ϫ2340; J.-G. Mao, Z. Wang, A. Clearfield, J. Chem. Soc.,
Dalton Trans. 2002, 4541Ϫ4546.
A. Cabeza, M. A. G. Aranda, S. Bruque, A. Clearfield, J.
Mater. Chem. 1999, 9, 571Ϫ578; Z.-M. Sun, J.-G. Mao, Y.-Q.
Sun, H.-Y. Zeng, A. Clearfield, New J. Chem. 2003, 27,
1326Ϫ1330.
M. R. S. J. Foreman, T. Gelbrich, M. B. Hursthouse, M. J.
Plater, Inorg. Chem. Commun. 2000, 3, 234Ϫ238.
R. Cao, Q. Shi, D. Sun, M. Hong, W. Bi, Y. Zhao, Inorg. Chem.
2002, 41, 6161Ϫ6168.
G. M. Sheldrick, SHELXTL, Crystallographic Software Pack-
3
˚
V/A
[11]
Z
Dc/g·cmϪ3
µ(Mo-Kα)/mmϪ1
F (000)
[12]
Reflections collected
Unique reflections
Observed data [I Ͼ 2σ(I)]
No. of parameters refined
Goodness-of-fit on F2
R1, wR2 [I Ͼ 2σ(I)]
R1, wR2 (all data)
[13]
[14]
[15]
age, version 5.1, Bruker-AXS, Madison, WI, 1998.
Received August 29, 2003
Early View Article
Published Online February 16, 2004
CCDC-217199 and -217200 contain the supplementary crystallo-
graphic data for this paper. These data can be obtained free of
1276
 2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
Eur. J. Inorg. Chem. 2004, 1270Ϫ1276