Coordination polymers based on porphyrin and copper: The influence of the crystallization solvents on the dimensionality of the network

Article abstract of DOI:10.1039/b206661k

The α₂β₂ atropoisomer of meso-tetrakis(o-nicotinoylamidophenyl)-copper porphyrin leads in the presence of Cu(II) cation to coordination polymers in the crystalline phase. The networks are generated by interconnection of metalloporphy

Full text of DOI:10.1039/b206661k

View Article Online / Journal Homepage / Table of Contents for this issue
Coordination polymers based on porphyrin and copper: the influence
of the crystallization solvents on the dimensionality of the network
a
Bertrand Zimmer, Marie Hutin, Veronique Bulach, Mir Wais Hosseini,*
a
a
a
´
Andre De Cian and Nathalie Kyritsakasb
ab
´
a
L e t t e r
´
Universite Louis Pasteur, Laboratoire de Chimie de Coordination Organique,
Institut Le Bel, 4, rue Blaise Pascal, F-67000, Strasbourg, France
´
Universite Louis Pasteur, Service Commun des Rayons X, Institut Le Bel, 4,
rue Blaise Pascal, F-67000, Strasbourg, France
b
Received (in Montpellier, France) 8th July 2002, Accepted 17th September 2002
First published as an Advance Article on the web 7th October 2002
Although the formation of coordination networks as well as
finite polynuclear assemblies based on porphyrin derivatives
bearing either pyridine or imidazole moieties directly con-
nected at the meso positions has been reported,5 to the best
of our knowledge, apart from a single example dealing with
a polymeric structure obtained in the presence of Fe(III),6 the
use of atropoisomers of meso-phenyl porphyrins bearing pyri-
dine units to generate coordination networks has not been
explored.
The a2b2 atropoisomer of meso-tetrakis(o-nicotinoylamidophe-
nyl)–copper porphyrin leads in the presence of Cu(II) cation to
coordination polymers in the crystalline phase. The networks
are generated by interconnection of metalloporphyrin units
through the coordination of Cu centres adopting an octahedral
coordination geometry by two pyridines belonging to consecutive
complexes. Depending on the solvent systems used, the 1-D coor-
dination network based on 1a2b2 and Cu dication was shown to
form a 3-D network based on a combination of three distinct
supramolecular forces.
Here we report the formation of two different coordination
networks formed upon crystallisation of the isolated copper
complex of 1a2b2 (Scheme 1).
In line with our continued efforts to design new types of tec-
tons for the formation of coordination networks,7 the a2b2
atropoisomer 1a2b2 of the porphyrin based tecton 1 bearing
four isonicotinoyl units was designed and prepared. It is worth
noting that, owing the bulkiness of the isonicotinoyl amido
Introduction
Coordination networks1 are sequenced molecular assemblies
composed of organic ligands and metallic centres acting as
building blocks or tectons. These infinite structures are
obtained upon mutual interconnection of organic tectons bear-
ing coordination sites and metal centres. The guidelines fol-
lowed for the design of coordination networks are: i) the
dimensionality and topology of the network (1-, 2- or 3-D)
which is defined by the number of translations operating on
the assembling nodes or coordination patterns connecting
the organic and the metallic tectons, ii) the nature of the coor-
dination pattern which strongly depends on the metal consid-
ered (coordination number and geometry), iii) the nature of
the organic tecton (number of coordination sites and the type
of hetero atom, the disposition of the coordination sites).
When considering a metallic tecton adopting an octahedral
coordination geometry, one of the multiple possibilities which
may be explored may be to use a tetradentate core capable of
occupying the square base of the octahedron and thus leaving
the two apical positions free for the generation of a 1-D net-
work. For that purpose, the porphyrin core,2 already widely
used in materials chemistry,3 appeared as the candidate of
choice for many reasons such as its binding ability towards a
variety of metal cations and the possibility of fine tuning of
the redox and/or photochemical properties of the correspond-
ing metal complex. Another interesting feature associated with
porphyrin backbone is the possibility of functionalising the
central core at b-pyrrolic and/or meso positions. Thus, based
on this preorganised tetradentate unit, one may design a vari-
ety of tectons by anchoring additional coordination sites such
as pyridine, nitrile, carboxylate etc. to the porphyrin core. In
particular, we have published a class of tectons based on a por-
phyrin core bearing at the meso positions phenylcatechoamido
groups.4
Scheme 1 Upon self-assembly of metalloporphyrin 1a2b2–Cu a 3-D
network was obtained in the crystalline phase. The network is based
on three distinct supramolecular synthons (coordination bonding,
p–p stacking, H-bonding).
1532
New J. Chem., 2002, 26, 1532–1535
DOI: 10.1039/b206661k
This journal is # The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2002

View Article Online
group, the a2b2 atropoisomer may be obtained in a pure form
and that the atropoisomerisation process leading to a mixture
is rather slow at room temperature.
The tecton 1 possesses four isonicotinoyl moieties and for
the a2b2 atropoisomer of 1, each face of the porphyrin is occu-
pied by two adjacent isonicotinoyl units. The synthesis of
1a2b2 was achieved in 68% yield upon treatment of the pure
8
tetraaminoporphyrin derivative 2a2b2 with isonicotinoyl
chloride in dry THF and in the presence of Et3N. This strategy
appeared as more viable since the separation of atropoisomers
of 1, obtained upon condensation of a statistical mixture con-
taining all four atropoisomers of 2 with isonicotinoyl chloride,
is extremely difficult.9
The structure of the free tecton 1a2b2 was elucidated in the
solid state by X-ray diffraction on a single crystal obtained
upon slow diffusion of hexane into a CHCl3 solution of the
compound 1a2b2 . The X-ray study was in agreement with
1H-NMR investigations in solution (Fig. 1). The porphyrin
ring is almost planar. The phenyl groups are tilted with respect
to the porphyrin ring by 64.2ꢀ and 83.7ꢀ. The amide junctions
between the phenyl groups and the pyridine ring are all in trans
Fig. 2 A portion of the crystal structure A showing the formation of
a 1-D coordination network obtained upon mutual interconnection of
1a2b2–Cu complexes through Cu–pyridine coordination bonds. Sol-
vent molecules (H2O and MeOH) and H atoms are not represented
for clarity. For the crystallisation conditions as well as bond distances
and angles see text.
˚
=
configuration with dC O and dC–N distances of 1.22 A and 1.35
˚
A respectively. The amide groups are, as expected, planar with
CCO, CCN and OCN angles of 121.0ꢀ, 115.2ꢀ and 123.7ꢀ
respectively. The pyridine units are almost coplanar with the
amide groups (OCNC dihedral angles of ꢁ0.4ꢀ and ꢁ2.9ꢀ).
For the formation of the network, Cu(II) was used as the
metallic centre. The choice of Cu(II) was related to the possibi-
lity of forming the copper–porphyrin complex under mild con-
ditions and thus avoiding atropoisomerisation of the
porphyrin derivative. The latter was obtained in 68% yield as
an orange powder upon treatment at rt of 1a2b2 with
Cu(OAc)2ꢂH2O in a CH2Cl2–MeOH 1 : 1 mixture. As a first
trial, single crystals of the metalloporphyrin were obtained
by slow diffusion of water into a methanol solution of
1a2b2–Cu. The X-ray diffraction study on a single crystal
by 28.5ꢀ and 34.0ꢀ. The angles between the pyridines and the
porphyrin ring are 53.3ꢀ and 87.9ꢀ. The Cu2+ cation, occupy-
ing the centre of symmetry, adopts a distorted octahedral
coordination geometry and is coordinated to the set of four
N atoms belonging to the porphyrin core (dCu–N of ca. 2.01
and 2.02 A). The two apical positions on the Cu cation are
occupied by two pyridine units belonging to two consecutive
˚
porphyrins (dCu–N of ca. 2.59 A) leading thus to a 1-D coordi-
˚
nation network (Fig. 2). It is worth noting that no structural
study dealing with a Cu–porphyrin complex adopting an octa-
hedral geometry has been reported so far.
Interestingly, the 1-D networks are interconnected through
p–p and dipole–dipole interactions leading thus to a 2-D net-
work. Indeed two adjacent pyridine units belonging to two
consecutive 1-D networks are arranged in a head-to-tail fash-
¯
revealed that the crystal A (triclinic system, P1 as the space
group, Z ¼ 1) is composed of doubly deprotonated 1a2b2 ,
Cu(II) cation, 4CH3OH and 3H2O molecules. The water mole-
cules are disordered over two positions. For the organic tecton
1a2b2 , the porphyrin macrocycle is almost planar (maximum
˚
ion with a distance of 3.67 A between their centroids (Fig. 3).
Furthermore, the 2-D networks thus formed are again inter-
connected through H-bonds engaging water molecules and O
atoms of the amide junctions with the O–O distance varying
˚
deviation of 0.04 A). The phenyl rings at the meso positions
are tilted with respect to the plane of the porphyrin by 70.7ꢀ
and 82.1ꢀ. All four amide groups (dC–N : 1.340 A and 1.346
between ca. 2.67–2.83 A (Fig. 4). Although the MeOH mole-
cules are H-bonded to each other and to H2O molecules,
they do not participate in the formation of the 3-D network.
˚
˚
˚
˚
˚
˚
˚
=
A; dC O : 1.224 A and 1.277 A; dC–C : 1.505 A and 1.507 A;
NCO angle of 123.5ꢀ; CCO angle of 120.8ꢀ and 118.8ꢀ; NCC
angle of 115.7ꢀ and 117.6ꢀ) are in trans configuration with
=
the C O fragments outwardly oriented. The pyridine units
are not coplanar with the connected phenyl groups but tilted
Fig. 3 A portion of the crystal structure A showing the formation of
a 2-D network. The latter is obtained upon p–p stacking of pyridine
rings (shown in green) belonging to adjacent 1-D coordination
networks and not involved in coordination bonds with Cu cations.
Solvent molecules and H atoms are not represented for clarity. For
the bond distances and angles see text.
Fig. 1 The crystal structures of 1a2b2 showing the localisation of the
pyridine groups with respect to the porphyrin backbone. Solvent mole-
cules and H atoms are not represented for clarity. For bond distances
and angles see text.
New J. Chem., 2002, 26, 1532–1535
1533

View Article Online
Fig. 5 A portion of the crystal structure B showing the formation of
a 1-D coordination network obtained upon mutual interconnection of
1a2b2–Cu complexes through Cu–pyridine coordination bonds. Sol-
vent molecules (DMF) and H atoms are not represented for clarity.
For the crystallisation conditions as well as bond distances and angles
see text.
Fig. 4 A portion of the crystal structure B showing the formation of
a 3-D network. The latter is obtained upon interconnection of the 2-D
=
networks through H-bonding between O atoms belonging to the C
O
groups of the metalloporphyrin 1a2b2–Cu and water molecules (disor-
dered). MeOH molecules and H atoms are not represented for clarity.
For the bond distances and angles see text.
Further studies along the same lines using other atropoiso-
mers of 1 and a variety of metal centres are currently under
investigation.
Unfortunately, because of the disorder observed for all three
H2O molecules (occupancy of 1/2), the network can not be
described in a simple fashion. It is of interest to point out that
for the structure described above, different types of supramole-
cular interaction (coordination bonding, p–p and dipole–
dipole interactions and hydrogen bonding) are operating in
concert to generate a 3-D network.
Upon slow diffusion of MeOH into a DMF solution con-
taining the 1a2b2–Cu complex a different type of single crystal
was obtained and studied by X-ray diffraction. The crystal B
Experimental
Synthesis of 1a2b2–Cu
In a round bottomed flask (100 ml), a mixture of the porphyrin
1a2b2 (0.10 g, 0.092 mmol) and Cu(OAc)2ꢂH2O (0,19 g, 0.95
mmol) in 50 ml of CH2Cl2–MeOH (1 : 1) was stirred at room
temperature for 1 hour. The solvents and volatiles were
removed under reduced pressure. The crude material was dis-
solved in CH2Cl2 (100 ml), washed with H2O (2 ꢃ 100 ml)
and dried over Na2SO4 . After filtration and evaporation of
the solvent, the orange powder was dried overnight under
vacuum affording the copper complex 1a2b2–Cu in 68%
yield which was characterised by absorption spectroscopy
(UV-VIS (CH3OH, lmax/nm; (e/dm3 molꢁ1 cmꢁ1)): 418
(2.7 ꢃ 105), 544 (1.9 ꢃ 104), 573 (6.2 ꢃ 103).
¯
(triclinic system, P1 as the space group, Z ¼ 1) is composed
of the 1a2b2–Cu complex and 2 DMF molecules. The solvent
molecules are H-bonded to the porphyrin complex through
the O atom of DMF and the NH moiety of the amide group
˚
of 1a2b2 (dN–O ¼ 2.869 A). The porphyrin core of 1a2b2 is
˚
again almost planar (maximum deviation of 0.09 A). The phe-
nyl rings are tilted with respect to the plane of the porphyrin by
63.9ꢀ and 70.8ꢀ. All four amide groups (CN, CO and CC dis-
˚
˚
˚
tances of ca. 1.36 A, 1.21 A and 1.50 A respectively and NCO
angles of 123.4ꢀ and 124.6ꢀ; CCO angle of 119.0ꢀ and 121.0ꢀ
and NCC angle of 114.3ꢀ and 117.4ꢀ) are again in trans config-
Crystal structure characterisation
X-Ray diffraction data collection was carried out on a Kappa
CCD diffractometer equipped with an Oxford Cryosystem
liquid N2 device, using graphite-monochromated Mo-Ka
radiation. For all structures, diffraction data were corrected
for absorption and analysed using the OpenMolen package.10
All non-H atoms were refined anisotropically.
CCDC reference numbers 190193–190195. See http://
www.rsc.org/suppdata/nj/b2/b206661k/ for crystallographic
files in CIF or other electronic format.
=
uration with the C O fragments outwardly oriented. The pyr-
idine units are not coplanar with the connected phenyl groups
but tilted by 37.7ꢀ and 46.7ꢀ. The angles between the pyridines
and the porphyrin ring are 75.6ꢀ and 85.8ꢀ. The Cu2+ cation,
again lying on the centre of symmetry, is coordinated to the
set of four N atoms belonging to the porphyrin core (dCu–N
˚
of ca. 2.01 A) and to two pyridine units belonging to two con-
˚
secutive porphyrins (dCu–N of ca. 2.58 A). Thus, again the same
type of 1-D coordination network (Fig. 5) as the one observed
when crystals were obtained in the presence of water is formed.
However, in marked contrast with the previous case, no stack-
ing interactions nor H-bonding are observed.
Crystallographic data for free 1a2b2 (red crystals, 173 K).
C68H46N12O4ꢂ5CHCl3 ,
M ¼ 1692.09,
triclinic,
a ¼
˚
12.8117(2), b ¼ 13.0953(2), c ¼ 13.5473(3) A, a ¼ 104.664(5),
3
ꢀ
˚
b ¼ 111.913(5), g ¼ 104.738(5) , U ¼ 1879.54(6) A , space
In summary, upon treatment of the a2b2 atropoisomer of the
porphyrin 1 bearing four isonicotinoyl moieties and Cu(OAc)2
the corresponding metalloporphyrin 1a2b2–Cu was synthe-
sised. The X-ray diffraction study revealed that the Cu(II)
cation is hexacoordinated and adopts adistorted octahedral
coordination geometry. Depending on the solvent systems
used, the 1a2b2–Cu complex leads either to a 1-D coordination
network (mixture of DMF and MeOH) or to a 3-D network
(H2O and MeOH). For the latter case, the 3-D network may
be described as a combination of different supramolecular
forces, i.e. coordination bonding, p–p stacking and dipole–
dipole interactions and H-bonding, operating simultaneously.
group P1, Z ¼ 1, Dc ¼ 1.49 g cmꢁ3; m ¼ 0.607 mmꢁ1, 4617
¯
data with I > 3s(I), R ¼ 0.069, Rw ¼ 0.083. All H atoms were
located except the two NH of the porphyrin ring, the two NH
of the amide groups and those belonging to CHCl3 solvent
molecules.
Crystallographic data for 3-D network A based on 1a2b2–Cu
(red crystals, 173 K). C68H44CuN12O4ꢂ4CH3OHꢂ3H2O, M ¼
1338.94, triclinic, a ¼ 9.9533(2), b ¼ 13.2375(4), c ¼
ꢀ
˚
13.3971(3) A, a ¼ 88.813(5), b ¼ 69.005(5), g ¼ 88.363(4) ,
3
˚
¯
U ¼ 1647.20(7) A , space group P1, Z ¼ 1, Dc ¼ 1.35 g
1534
New J. Chem., 2002, 26, 1532–1535

View Article Online
cmꢁ3; m ¼ 0.403 mmꢁ1, 4876 data with I > 3s(I), R(int) ¼
0.04, R ¼ 0.054, Rw ¼ 0.068. All H atoms were located except
those belonging to solvent molecules which were found to be
disordered.
Planeix, G. Stupka, A. De Cian and J. Fischer, Chem. Commun.,
1998, 689; B. Zimmer, V. Bulach, C. Drexler, S. Erhardt, M. W.
Hosseini and A. De Cian, New J. Chem., 2002, 26, 43.
5
B. F. Abrahams, B. F. Hoskins and R. Robson, J. Am. Chem.
Soc., 1991, 113, 3606; E. B. Fleischer and A. M. Shachter, Inorg.
Chem., 1991, 30, 3763; B. F. Abrahams, B. F. Hoskins, D. M.
Michail and R. Robson, Nature, 1994, 369, 727; H. Krupitsky,
Z. Stein, I. Goldberg and C. E. Strouse, J. Inclusion Phenom.
Mol. Recognit. Chem., 1994, 18, 177; L. Pan, B. C. Noll and W.
Wang, Chem. Commun., 1999, 157; U. Michelsen and C. A. Hun-
ter, Angew. Chem., Int. Ed., 2000, 39, 764; I. Goldberg, Chem.
Eur. J., 2000, 6, 3863; K. Ogawa and Y. Kobuke, Angew Chem.,
Int. Ed., 2000, 39, 4070; C. M. Drain and J.-M. Lehn, J. Chem.
Soc., Chem. Commun., 1994, 2313; P. J. Stang, J. Fan and B.
Olenyuk, Chem. Commun., 1997, 1453; R. V. Slone and J. T.
Hupp, Inorg. Chem., 1997, 36, 5422; A. Ikeda, M. Ayabe, S.
Shinkai, S. Sakamoto and K. Yamaguchi, Org. Lett., 2000, 2,
3707.
M. J. Gunter, G. M. McLaughlin, K. J. Berry, K. S. Murray, M.
Irving and P. E. Clark, J. Am. Chem. Soc., 1984, 23, 283.
C. Kaes, M. W. Hosseini, C. E. F. Rickard, B. W. Skelton and A.
White, Angew. Chem., Int. Ed., 1998, 37, 920; G. Mislin, E. Graf,
M. W. Hosseini, A. De Cian, N. Kyritsakas and J. Fischer, Chem.
Commun., 1998, 2545; M. Lo¨ı, M. W. Hosseini, A. Jouaiti, A. De
Cian and J. Fischer, Eur. J. Inorg. Chem., 1999, 1981; M. Lo¨ı, E.
Graf, M. W. Hosseini, A. De Cian and J. Fischer, Chem. Com-
mun., 1999, 603; C. Klein, E. Graf, M. W. Hosseini, A. De Cian
and J. Fischer, Chem. Commun., 2000, 239; H. Akdas, E. Graf,
M. W. Hosseini, A. De Cian and J. McB. Harrowfield, Chem.
Commun., 2000, 2219; A. Jouaiti, M. W. Hosseini and A. De Cian,
Chem. Commun., 2000, 1863; B. Schmaltz, A. Jouaiti, M. W.
Hosseini and A. De Cian, Chem. Commun., 2001, 1242; A. Jouaiti,
V. Jullien, M. W. Hosseini, J.-M. Planeix and A. De Cian, Chem.
Commun., 2001, 1114; C. Klein, E. Graf, M. W. Hosseini, A. De
Cian and J. Fischer, New J. Chem., 2001, 25, 207; S. Ferlay, S.
Koenig, M. W. Hosseini, J. Pansanel, A. De Cian and N.
Kyritsakas, Chem. Commun., 2002, 218.
Crystallographic data for 1-D network B based on 1a2b2–Cu
(brown crystals, 173 K). C68H44CuN12O4ꢂ2C3H7NO, M ¼
1302.92, triclinic, a ¼ 11.0102(2), b ¼ 11.3676(2) c ¼
ꢀ
˚
13.6847(3) A, a ¼ 76.117(5), b ¼ 82.625(5), g ¼ 65.319(5) ,
3
˚
¯
U ¼ 1510.07(5) A , space group P1, Z ¼ 1, Dc ¼ 1.43 g
cmꢁ3
;
m ¼ 0.433 mmꢁ1
,
4301 data with I > 3s(I),
R(int) ¼ 0.04, R ¼ 0.044, Rw ¼ 0.063. All H atoms were
located.
Acknowledgements
6
7
´
We thank the Universite Louis Pasteur and the Ministry of
Research and Technology for financial support and a scholar-
ship to B. Zimmer.
References
1
S. R. Batten and R. Robson, Angew. Chem., Int. Ed., 1998, 37,
1460; A. J. Blake, N. R. Champness, P. Hubberstey, W.-S. Li,
M. A. Withersby and M. Scho¨der, Coord. Chem. Rev., 1999,
183, 117M. W. Hosseini, in NATO ASI Series, ed. D. Braga, F.
Grepiono and G. Orpen, Serie C, Kluwer, Dordrecht, Nether-
lands, 1999, vol. 538, p. 181; M. Eddaoudi, D. B. Moler, H. Li,
B. Chen, T. M. Reineke, M. O’Keeffe and O. M. Yaghi, Acc.
Chem. Res., 2001, 34, 319; B. Moulton and M. J. Zaworotko,
Chem. Rev., 2001, 101, 1629.
2
3
The Porphyrin Handbook, ed. K. M. Kadish, K. M. Smith and
R. Guilard, Academic Press, 2000, vol. 1–10.
J. H. Chou, H. S. Nalwa, M. E. Kosal, N. A. Rakow and K. S.
Suslick, in The Porphyrin Handbook, Academic Press, Orlando,
FL, 2000, vol. 6, ch. 41, p. 43.
8
9
J. P. Collman, R. R. Gagne, C. A. Reed, T. R. Halbert, G. Lang
and W. T. Robinson, J. Am. Chem. Soc., 1975, 97, 1427.
A. Valliot, A. Adeyemo, R. F. X. Williams, L. Ricks, J. North and
P. Hambright, J. Inorg. Nucl. Chem., 1981, 43, 2653.
4
C. Drexler, M. W. Hosseini, A. De Cian and J. Fischer, Tetrahe-
dron Lett., 1997, 38, 2993; C. Drexler, M. W. Hosseini, J.-M.
10 OpenMolenN, Interactive Structure Solution, B. V. Nonius,
Delft, The Netherlands, 1997.
New J. Chem., 2002, 26, 1532–1535
1535