Control of copper(I) iodide architectures by ligand design: Angular versus linear bridging ligands

Article abstract of DOI:10.1021/ic052130k

A family of coordination polymers formed by the reaction of copper(I) iodide with a range of angular bidentate or tridentate N-donor ligands is reported. The framework polymers [CuI(dpt)]_∞ 1 [dpt = 2,4-bis(4-pyridyl)-1,3,5-triazine], [CuI(dpb)]_∞ 2 [dpb = 1,4-bis-(4-pyridyl)-benzene], [(CuI)₃(dpypy)₂] _∞ 3, [CuI(dpypy)]_∞ 4 [dpypy = 3,5-bis(4-pyridyl)-pyridine], and [Cu₃I₃(pypm)] _∞ 5 [pypm = 5-(4-pyridyl)pyrimidine] have been prepared and structurally characterized. It was found that the angular nature of the dpypy and dpt ligands favors the formation of discrete (CuI)₂ dimeric subunits as observed in [CuI(dPt)·MeCN]_∞ 1 and [(CuI)₃(dpypy)₂]_∞ 3. In contrast, reaction with the linear ligand dpb affords [CuI(dpb)]_∞ 2 which incorporates a one-dimensional (CuI)_∞ chain structure. Moreover, the additional donor available on the central ring of the dpypy ligand generates a novel two-dimensional bilayer structure in 3, in contrast to the one-dimensional ribbon structure observed in the case of 1. Interestingly, the bilayer structure of 3 additionally exhibits 2-fold interpenetration. The reaction of CuI with dpypy produces not only 3 but a further product [CuI-(dpypy)]_∞ 4 that has been characterized as a one-dimensional chain constructed from trigonal-planar Cu(I) centers bridged by bidentate dpypy ligands. Compound 5, [Cu₃I₃(pypm)] _∞, exhibits a highly unusual three-dimensional structure in which the pypm ligand bridges two-dimensional brick-wall (CuI)_∞ sheets.

Full text of DOI:10.1021/ic052130k

Inorg. Chem. 2006, 45, 6179−6187
Control of Copper(I) Iodide Architectures by Ligand Design: Angular
versus Linear Bridging Ligands
Fre´de´ric The´bault, Sarah A. Barnett, Alexander J. Blake, Claire Wilson, Neil R. Champness,* and
Martin Schro1der*
School of Chemistry, The UniVersity of Nottingham, UniVersity Park, Nottingham NG7 2RD, U.K.
Received December 13, 2005
A family of coordination polymers formed by the reaction of copper(I) iodide with a range of angular bidentate or
tridentate N-donor ligands is reported. The framework polymers [CuI(dpt)]∞ 1 [dpt 2,4-bis(4-pyridyl)-1,3,5-triazine],
[CuI(dpb)]∞ 2 [dpb 1,4-bis-(4-pyridyl)-benzene], [(CuI)3(dpypy)2]∞ 3, [CuI(dpypy)]∞ 4 [dpypy 3,5-bis(4-pyridyl)-
pyridine], and [Cu3I3(pypm)]∞ 5 [pypm 5-(4-pyridyl)pyrimidine] have been prepared and structurally characterized.
It was found that the angular nature of the dpypy and dpt ligands favors the formation of discrete (CuI)2 dimeric
subunits as observed in [CuI(dpt) MeCN]∞ 1 and [(CuI)3(dpypy)2]∞ 3. In contrast, reaction with the linear ligand dpb
)
)
)
)
‚
affords [CuI(dpb)]∞ 2 which incorporates a one-dimensional (CuI)∞ chain structure. Moreover, the additional donor
available on the central ring of the dpypy ligand generates a novel two-dimensional bilayer structure in 3, in contrast
to the one-dimensional ribbon structure observed in the case of 1. Interestingly, the bilayer structure of 3 additionally
exhibits 2-fold interpenetration. The reaction of CuI with dpypy produces not only 3 but a further product [CuI-
(dpypy)]∞ 4 that has been characterized as a one-dimensional chain constructed from trigonal-planar Cu(I) centers
bridged by bidentate dpypy ligands. Compound 5, [Cu3I3(pypm)]∞, exhibits a highly unusual three-dimensional
structure in which the pypm ligand bridges two-dimensional brick-wall (CuI)∞ sheets.
Introduction
potential for a high degree of design with targeting of specific
properties.2 However, the targeted synthesis of such polymers
requires not only an appreciation of the variety of possible
coordination framework materials that can be prepared from
a given set of building-block components but also an
appreciation of which structures and topologies are favored
and why. The incorporation of building-blocks with a high
degree of geometric flexibility can afford a large range of
possible structures leading in turn to an almost complete
absence of predictability.3 However, this flexibility also can
lead to the observation of highly unusual structures.4
For some time we have been interested in the large
structural variation exhibited by copper(I) halides, pseudo-
halides [Cu(SCN)], and in particular copper(I) iodide5-8
which are known to exhibit fluorescent properties.9 The
strongly coordinating nature of the halide anion is such that
The construction of coordination frameworks is an ex-
tremely topical area of chemistry because of their potential
as new materials with tunable properties.1 As these materials
become more highly evolved, properties can become more
highly tuned, leading to the development of useful, func-
tional, and even polyfunctional materials. The high levels
of interest in this area of research arise also because the main
synthetic methodology used in the construction of these
materials, a building-block approach based upon bridging
metal cationic nodes with bridging ligands, allows the
* To whom correspondence should be addressed. E-mail:
Neil.Champness@nottingham.ac.uk (N.R.C.), M.Schroder@nottingham.ac.uk
(M.S.).
(1) (a) Noro, S.; Kitagawa, S.; Kondo, M.; Seki, K. Angew. Chem., Int.
Ed. 2000, 39, 2082. (b) Kitaura, R.; Kitagawa, S.; Kubota, Y.;
Kobayashi, T. C.; Kindo, K.; Mita, Y.; Matsuo, A.; Kobayashi, M.;
Chang, H. C.; Ozawa, T. C.; Suzuki, M.; Sakata, M.; Takata, M.
Science 2002, 298, 2358. (c) Kahn, O. Acc. Chem. Res. 2000, 33,
647. (d) Evans, O. R.; Lin, W. Acc. Chem. Res. 2002, 35, 511. (e)
Maspoch, D.; Ruiz-Molina, D.; Wurst, K.; Domingo, N.; Cavallini,
M.; Biscarini, F.; Tejada, J.; Rovira, C.; Veciana, J. Nat. Mater. 2003,
2, 190. (f) Coronado, E.; Galan-Mascaros, J. R.; Gomez-Garcia, C.
J.; Laukhin, V. Nature 2000, 408, 447. (g) Champness, N. R.; Schro¨der,
M. Curr. Opin. Solid State Mater. Chem. 1998, 3 419.
(2) (a) Hoskins, B. F.; Robson, R. J. Am. Chem. Soc. 1990, 112, 1546.
(b) Robson, R.; Abrahams, B. F.; Batten, S. R.; Gable, R. W.; Hoskins,
B. F.; Liu, J. P. ACS Symp. Ser. 1992, 499, 256.
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145. (b) Barnett, S. A.; Blake, A. J.; Champness, N. R.; Wilson, C. J.
Chem. Soc., Dalton Trans. 2005, 3852. (c) Oxtoby, N. S.; Blake, A.
J.; Champness, N. R.; Wilson, C. Proc. Natl. Acad. Sci. U.S.A. 2002,
99, 4905.
10.1021/ic052130k CCC: $33.50
Published on Web 04/05/2006
© 2006 American Chemical Society
Inorganic Chemistry, Vol. 45, No. 16, 2006 6179

The´bault et al.
Chart 1
it can bridge two or more copper centers giving neutral
species of the form (CuX)n (X ) Cl, Br or I; n ) 1, 2, 3, 4,
..., ∞). These species can have discrete molecular structures
(e.g. rhomboid dimer or cubane tetramers),7a,10 one-dimen-
sional structures (e.g. staircase chains, split staircase chains,
zigzag chains, or hexagonal columns),7b,c,11 or two-dimen-
sional structures (e.g. corrugated sheets),7c which can be
connected to form coordination polymers using diverse
bridging ligands. For example, when combined with the
bridging bidentate ligands pyrimidine, pyrazine, 4,4′-bipyr-
idine, 2,7-diazapyrene, quinoxaline, and 4,7-phenanthroline,
two-dimensional sheets comprising one-dimensional (CuX)∞
motifs linked by the bridging ligand are produced.7b Simi-
larly, 1,3,5-triazine in combination with copper(I) halides
generates three-dimensional arrays consisting of either one-
dimensional (CuX)∞ motifs linked by tridentate triazine or
two-dimensional (CuX)∞ motifs joined by bidentate triazine.7c
We report herein the synthesis, crystallization, and struc-
tural characterization of a range of CuI-based coordination
polymer arrays formed using angular12a,c bidentate or triden-
tate N-donor ligands. The ligands (Chart 1) were chosen to
illustrate the influence of the angular nature of the N-donor
groups and to attempt to gain a degree of control over the
nature of the (CuI)∞ motif adopted. As will be seen, the
angular nature of the ligand, in the case of 3,5-bis(4-pyridyl)-
pyridine (dpypy) and 2,4-bis(4-pyridyl)-1,3,5-triazine (dpt),
can favor the formation of discrete (CuI)2 dimeric subunits
as observed in [CuI(dpt)‚MeCN]∞ 1 and [(CuI)3(dpypy)2]∞
3 in preference to the one-dimensional (CuI)∞ chain structure
seen for [CuI(dpb)]∞ 2 which contains the linear ligand 1,4-
bis(4-pyridyl)-benzene (dpb). The ligand dpypy can also act
as a bidentate ligand rather than a tridentate building block
as in 3: thus, reaction of CuI with dpypy affords an
additional product, 4, that has been characterized as a one-
dimensional chain constructed from trigonal planar Cu(I)
centers bridged by terminally coordinated dpypy ligands.
With the use of the ligand 5-(4-pyridyl)pyrimidine (pypm),
an array of higher dimensionality has also been prepared:
[Cu3I3(pypm)]∞ 5 represents the first example of a previously
unknown type of copper iodide sheet with a 63 brick-wall
type structure.13
(4) (a) Li, D.; Wu, T.; Zhou, X. P.; Zhou, R.; Hitang, X. C. Angew. Chem.,
Int. Ed. 2005, 44, 4175. (b) Zhang, X. M.; Fang, R. Q.; Wu, H. S. J.
Am. Chem. Soc. 2005, 127, 7670. (c) Long, D.-L.; Hill, R. J.; Blake,
A. J.; Champness, N. R.; Hubberstey, P.; Proserpio, D. M.; Wilson,
C.; Schro¨der, M. Angew. Chem., Int. Ed. 2004, 43, 1851. (d) Long,
D.-L.; Blake, A. J.; Champness, N. R.; Wilson, C.; Schro¨der, M.
Angew. Chem., Int. Ed. 2001, 40, 2444. (e) Long, D.-L.; Blake, A. J.;
Champness, N. R.; Wilson, C.; Schro¨der, M. Chem.sEur. J. 2002, 8,
2026.
(5) (a) Blake, A. J.; Brooks, N. R.; Champness, N. R.; Hanton, L. R.;
Hubberstey, P.; Schro¨der, M. Pure Appl. Chem. 1998, 70, 2351. (b)
Brooks, N. R.; Blake, A. J.; Champness, N. R.; Cooke, P. A.;
Hubberstey, P.; Proserpio, D. M.; Wilson, C.; Schro¨der, M. J. Chem.
Soc., Dalton Trans. 2001, 456.
(6) (a) Hu, S.; Tong, M. L. J. Chem. Soc., Dalton Trans. 2005, 1165. (b)
Nather, C.; Wriedt, M.; Jess, I. Inorg. Chem. 2003, 42, 2391. (c)
Nather, C.; Jess, I. Inorg. Chem. 2003, 42, 2968. (d) Pike, R. D.; Borne,
B. D.; Maeyer, J. T.; Rheingold, A. L. Inorg. Chem. 2002, 41, 631.
(e) Peng, R.; Wu, T.; Li, D. CrystEngComm [Online] 2005, 7, 595.
(7) (a) Blake, A. J.; Brooks, N. R.; Champness, N. R.; Crew, M.; Gregory,
D. H.; Hubberstey, P.; Schro¨der, M.; Deveson, A.; Fenske, D.; Hanton,
L. R. Chem. Commun. 2001, 1432. (b) Blake, A. J.; Brooks, N. R.;
Champness, N. R.; Cooke, P. A.; Crew, M.; Deveson, A. M.; Hanton,
L. R.; Hubberstey, P.; Fenske, D.; Scho¨der, M. Cryst. Eng. 1999, 2,
181. (c) Blake, A. J.; Brooks, N. R.; Champness, N. R.; Cooke, P. A.;
Deveson, A. M.; Fenske, D.; Hubberstey, P.; Li, W.-S.; Schro¨der, M.
J. Chem. Soc., Dalton Trans. 1999, 2103.
(8) (a) Barnett, S. A.; Blake, A. J.; Champness, N. R.; Wilson, C. Chem.
Commun. 2002, 1640. (b) Blake, A. J.; Champness, N. R.; Crew, M.;
Hanton, L. R.; Parsons, S.; Schro¨der, M. J. Chem. Soc., Dalton Trans.
1998, 1533. (c) Blake, A. J.; Brooks, N. R.; Champness, N. R.; Crew,
M.; Hanton, L. R.; Hubberstey, P.; Parsons, S. M.; Schro¨der, M. J.
Chem Soc., Dalton Trans. 1999, 2813. (d) Barnett, S. A.; Blake, A.
J.; Champness, N. R.; Wilson, C. CrystEngComm 2000, 2, 36.
(9) (a) Cariati, E.; Roberto, D.; Ugo, R.; Ford, P. C.; Galli, S.; Sironi, A.
Inorg. Chem. 2005, 44, 4077. (b) Vitale, M.; Ford, P. C. Coord. Chem.
ReV. 2001, 219, 3.
Experimental Section
General. Ligands were prepared either by literature methods
(dpt,14 dpb15) or as described below using Suzuki coupling
methodology. All other starting materials were purchased from
Aldrich or Lancaster and used without further purification. 1H NMR
and elemental analysis measurements were performed at the
University of Nottingham. Accurate mass spectrometry measure-
ments were performed by electrospray techniques at the EPSRC
National Mass Spectrometry Service Centre at Swansea University.
(10) (a) Amoore, J. J. M.; Hanton, L. R.; Spicer, M. D. J. Chem. Soc.,
Dalton Trans. 2003, 1056. (b) Caradoc-Davies, P. L.; Gregory, D.
H.; Hanton, L. R.; Turnbull, J. M. J. Chem. Soc., Dalton Trans. 2002,
1574. (c) Yaghi, O. M.; Li, G. Angew. Chem., Int. Ed. Engl. 1995,
34, 207. (d) Hu, S.; Chen, J.-C.; Tong, M.-L.; Wang, B.; Yan, Y.-X.;
Batten, S. R. Angew. Chem., Int. Ed. 2005, 44, 5471.
(11) (a) Caradoc-Davies, P. L.; Hanton, L. R.; Hodgkiss, J. M.; Spicer, M.
D. J. Chem. Soc., Dalton Trans. 2002, 1581. (b) Kuhn, N.; Fawzi, R.;
Grathwohl, M.; Kotowski, H.; Steimann, M. Z. Anorg. Allg. Chem.
1998, 624, 1937. (c) Su, C.-Y.; Kang, B.-S.; Sun, J. Chem. Lett. 1997,
821. (d) Dai, J.; Munakata, M.; Wu, L.-P.; Kuroda-Sowa, T.; Suenaga,
Y. Inorg. Chim. Acta 1997, 258, 65. (e) Graham, A. J.; Healy, P. C.;
Kildea, J. D.; White, A. H. Aust. J. Chem. 1989, 42, 177. (f) Healy,
P. C.; Kildea, J. D.; White, A. H. J. Chem. Soc., Dalton Trans. 1988,
1637. (g) Rath, N. P.; Holt, E. M.; Tanimura, K. J. Chem. Soc., Dalton
Trans. 1986, 2303. (h) Healy, P. C.; Pakawatchai, C.; Raston, C. L.;
Skelton, B. W.; White, A. H. J. Chem. Soc., Dalton Trans. 1983, 1905.
(i) Churchill, M. R.; DeBoer, B. G.; Donovan, D. J. Inorg. Chem.
1975, 14, 617. (j) Li, G.; Shi, Z.; Liu, X.; Dai, Z.; Feng, S. Inorg.
Chem. 2004, 43, 6884.
(12) (a) Barnett, S. A.; Blake, A. J.; Champness, N. R.; Nicolson, J. E. B.;
Wilson, C. J. Chem. Soc., Dalton Trans. 2001, 567. (b) Sasa, M.;
Tanaka, K.; Bu, X.-H.; Shiro, M.; Shionoya, M. J. Am. Chem. Soc.
2001, 123, 10750. (c) In this article, the term angular ligand is used
to describe a bridging ligand in which the donor atoms are disposed
at a defined angle with respect to each other (see ref 11).
(13) For an excellent introduction to network structures and topology we
would encourage readers to study the following. Molecule-Based
Materials: The Structural Network Approach; O¨ hrstro¨m, L., Larsson,
K. Eds.; Elsevier: Amsterdam, 2005.
(14) Fischer, H.; Summers, L. A. Tetrahedron 1976, 32, 615.
(15) Biradha, K.; Fujita, M. J. Chem. Soc., Dalton Trans. 2000, 3805.
6180 Inorganic Chemistry, Vol. 45, No. 16, 2006

Control of Copper(I) Iodide Architectures
Table 1. Selected Bond Lengths (Å) and Angles (deg) for
[(CuI)(dpt)]∞ (1) and [CuI(dpb)]∞ (2)a
An alternative but similar preparation route for the ligand dpypy is
available in the literature.16
5-(4-Pyridyl)pyrimidine (pypm). 4-(4,4,5,5-Tetramethyl-1,3,2-
dioxaborolan-2-yl)-pyridine17 (2.05 g, 10 mmol), 5-bromopyrimi-
dine (1.6 g, 10 mmol), cesium carbonate (5 g, 15 mmol), and
tetrakis(triphenylphosphine)palladium(0) (0.115 g, 0.1 mmol) were
added to 100 cm3 of deoxygenated DMF in a 250 cm3 three-necked,
round-bottom flask equipped with a condenser and containing a
nitrogen atmosphere. The solution was protected from light with
aluminum foil and heated in an oil bath at 95 °C for 8 days. DMF
was then removed by evaporation, and the product was separated
by column chromatography on silica gel 60 using water as the eluent
(white powder, yield 1.30 g, 83%). Found (calcd for C18H16N6O
{pypm‚0.5H2O}) (%): C, 65.39 (65.06); H, 4.44 (4.82); N, 24.15
(25.30). 1H NMR (CDCl3, δ in ppm): 9.33 (s, 1 H), 9.03 (s, 2 H),
8.80 (dd, 2 H, J1 ) 2.8 Hz, J2 ) 1.7 Hz), 7.54 (dd, 2 H, J1 ) 2.8
Hz, J2 ) 1.6 Hz). 13C NMR (CDCl3, δ in ppm): 158.8, 155.0,
150.6, 141.9, 131.6, 121.4. IR (KBr) (cm-1): 3039 (w), 1704 (w),
1603 (m), 1568 (m), 1416 (m), 1327 (w), 1293 (w), 1221 (w), 1128
(w), 1059 (w), 993 (w), 923 (w), 819 (m), 780 (w), 724 (m), 631
(w), 586 (m). Accurate mass spectrometry (AMS) [M + H]+, found
(calcd): 158.0715 (158.0713).
1
2
Cu1-N1
Cu1-N16i
Cu1-I1
2.037(3)
2.050(3)
2.6236(7)
2.7266(8)
2.033(4)
2.037(4)
2.6382(8)
2.6956(8)
Cu1-I1
2.6094(4)
2.074(2)
Cu1-N1
Cu1-I2
Cu2-N21
Cu2-N36i
Cu2-I2
Cu2-I1
N1-Cu1-N16i
N1-Cu1-I1
N16i-Cu1-I1
N1-Cu1-I2
N16i-Cu1-I2
I1-Cu1-I2
121.36(14)
109.78(10)
109.70(10)
105.24(9)
105.33(10)
103.82(2)
120.29(15)
109.09(10)
108.72(10)
105.33(10)
107.95(10)
104.28(2)
N1-Cu1-N1i
N1-Cu1-I1ii
N1-Cu1-I1
N1i-Cu1-I1
I1-Cu1-I1ii
101.20(14)
109.61(7)
114.15(7)
109.61(7)
108.17(2)
N21-Cu2-N36i
N21-Cu2-I2
N36i-Cu2-I2
N21-Cu2-I1
N36i-Cu2-I1
I2-Cu2-I1
a Symmetry transformations used to generate equivalent atoms. 1: (i) x,
y + 1, z - 1. 2: (i) -x + /2, -y - /2, z; (ii) x, y - 1, z.
1
1
3,5-Bis(4-pyridyl)-pyridine (dpypy). 4-(4,4,5,5-Tetramethyl-
1,3,2-dioxaborolan-2-yl)-pyridine17 (2.05 g, 10 mmol), 3,5-dibro-
mopyridine (1.18 g, 5 mmol), cesium carbonate (5 g, 15 mmol),
and tetrakis(triphenylphosphine)palladium(0) (0.115 g, 0.1 mmol)
were added in 100 cm3 of deoxygenized toluene/ethanol (95/5) in
a 250 cm3 three-necked, round-bottom flask equipped with a
condenser and containing a nitrogen atmosphere. The solution was
protected from light with aluminum foil and heated at 95 °C for 8
days using an oil bath. The solvent was then evaporated, and the
product was separated by column chromatography on silica gel 60
using acetone as the eluent (white powder, yield 0.63 g, 54%).
Found (calcd for C22H19N3 {dpypy‚C6H5Me}) (%): C, 82.49
(81.23); H, 5.17 (5.85); N, 12.33 (12.92). Repeated attempts to
obtain satisfactory elemental analysis for samples of dpypy were
unsuccessful because of varying degrees of solvation by a variety
of solvent species. 1H NMR (CDCl3, δ in ppm): 8.98 (d, 2 H, J )
2.2 Hz), 8.79 (dd, 4 H), 8.15 (t, 1 H, J ) 2.2 Hz), 7.60 (dd, 4 H,
J1 ) 2.8 Hz, J2 ) 1.7 Hz). 13C NMR (CDCl3, δ in ppm): 151.7,
148.4, 144.7, 134.3, 132.8, 121.7. IR (KBr) (cm-1): 3028 (w), 1603
(m, 1551 (w), 1402 (m), 1322 (w), 1222 (w), 1026 (w), 992 (w),
917 (w), 815 (s), 715 (m), 627 (w), 543 (m). AMS [M + H]+,
found (calcd): 234.1026 (234.1026).
(volume of 2 cm3) which was in turn placed in a larger vial (volume
of 10 cm3) which was carefully filled with MeCN to avoid rapid
mixing of the two reagent solutions. Orange crystals of 3 grew in
the ligand-rich region of the layering experiment, and yellow
crystals grew in the metal-rich region. A pure phase of 2 could
also be prepared by precipitation from rapidly mixed solutions of
dpb and CuI (1:1 stoichiometry) in MeCN. Yield 27%. Found (calcd
for C16H12CuIN2 [(CuI)(dpb)]) (%): C, 45.40 (45.45); H, 2.63
(2.84); N, 6.38 (6.63). IR (KBr) (cm-1): 3073 (w), 1592 (m), 1549
(m), 1481 (m), 1420 (m), 1404 (m), 1230 (m), 1042 (w), 991 (w),
797 (s), 704 (m), 586 (m), 461 (w).
[CuI(dpypy)]∞ (3, 4). The dpypy (5 mg, 0.01 mmol) and CuI
(15 mg, 0.01 mmol) were dissolved in DMF (2 cm3) and stirred
for 5 min. The solution was then placed in a steel autoclave which
was heated at 150 °C for 5 days. After the autoclave was cooled,
the sample was retrieved as orange columnar crystals in 95% yield.
Attempts to obtain CHN elemental analysis were unsuccessful
because of the mixture of phases obtained (see Results and
Discussion).
{Cu3I3(pypm)}∞ (5). CuI (30 mg) and 5-(4-pyridyl)-pyrimidine
(30 mg) were added to a water/acetonitrile solution (50/50, 5 cm3)
and stirred for 5 min. The solution was then placed in a steel
autoclave and heated at 120 °C for 5 days. Orange crystalline
needles formed at the bottom of the vial: these were extracted from
the solution and stored in n-hexane. Found (calcd for C9H7Cu3I3N3
{Cu3I3(5-pypm)}∞]) (%): C, 15.38 (14.83); H, 0.78 (0.96); N, 5.86
(5.77). IR (KBr) (cm-1): 1608 (m), 1574 (m), 1413 (m), 1403 (s),
1351 (w), 1322 (w), 1174 (w), 1068 (w), 1009 (w), 916 (w), 824
(s), 801 (w), 669 (w), 651 (w), 585 (w), 564 (m).
[(CuI)(dpt)‚MeCN]∞ (1). A solution of dpt (93 mg, 0.40 mmol)
in CH2Cl2 (3 cm3) was added to a cooled solution of CuI (76 mg,
0.40 mmol) dissolved in hot MeCN (20 cm3). The reddish-brown
precipitate that formed immediately was collected by filtration and
dried in vacuo. Yield 89%. Found (calcd for C13H9CuIN5 [(CuI)-
(dpt)]) (%): C, 37.39 (36.68); H, 2.07 (2.14); N, 16.33 (16.46). IR
(KBr) (cm-1): 2966 (w), 2955 (w), 2848 (w), 1655 (w), 1637 (w),
1567 (m), 1528 (s), 1508 (m), 1417 (s), 1385 (m), 1317 (w), 1300
(w), 1261 (w), 1055 (w), 798 (m), 671 (w), 650 (w), 419 (m).
Crystals suitable for single-crystal X-ray diffraction were prepared
by the slow diffusion of a solution of CuI in MeCN into a solution
of dpt in CH2Cl2.
X-ray Crystallographic Studies. Single crystal X-ray data
collections were performed on a Bruker SMART1000 (1), on a
Bruker SMART APEX CCD area detector diffractometer for 2-5,
and on a Bruker-Nonius kappaCCD area detector diffractometer
for pypm‚H2O. Structures were solved by direct methods using
SHELXS97,18 and full-matrix least squares refinement employed
[CuI(dpb)]∞ (2). Compound 2 was prepared by the slow
diffusion of solutions of dpb (5 mg, 0.01 mmol) and CuI (15 mg,
0.01 mmol) in MeCN (2 cm3). Each solution was placed in a vial
(16) Kubota, Y.; Biradha, K.; Fujita, M.; Sakamoto, S.; Yamaguchi, K.
Bull. Chem. Soc. Jpn. 2002, 75, 559.
(17) Coudret, C. Synth. Commun. 1996, 26, 3543.
(18) Sheldrick, G. M. SHELXS97; University of Go¨ttingen: Go¨ttingen,
Germany, 1997.
Inorganic Chemistry, Vol. 45, No. 16, 2006 6181

The´bault et al.
Table 2. Selected Bond Lengths (Å) and Angles (deg) for [(CuI)3(dpypy)2]∞ (3), [CuI(dpypy)]∞ (4), and {Cu3I3(5-pypm)}∞ (5)a
3
Cu1-I1
2.650(2)
2.632(3)
2.043(15)
2.029(14)
2.683(2)
2.680(2)
2.050(14)
2.063(14)
2.638(3)
2.638(3)
2.038(15)
2.045(14)
2.737(3)
2.653(3)
2.055(14)
2.021(14)
2.678(3)
2.710(3)
2.018(15)
2.028(15)
2.672(3)
2.692(3)
1.999(15)
2.025(14)
N11i-Cu1-N8
N11i-Cu1-I2
N8-Cu1-I2
N11i-Cu1-I1
N8-Cu1-I1
I2-Cu1-I1
115.3(7)
105.1(4)
109.5(5)
104.6(4)
110.1(4)
112.14(9)
125.6(6)
104.3(4)
106.2(4)
104.9(4)
105.7(4)
109.64(9)
122.5(6)
108.0(4)
106.8(4)
103.3(4)
102.5(4)
113.88(9)
122.6(6)
105.9(4)
105.5(4)
105.7(4)
106.6(4)
110.24(9)
N7ii-Cu5-N9
N7ii-Cu5-I5
N9-Cu5-I5
N7ii-Cu5-I6
N9-Cu5-I6
I5-Cu5-I6
121.5(6)
110.5(4)
110.5(4)
106.7(4)
106.7(4)
98.15(8)
122.1(6)
110.7(5)
110.2(4)
106.3(4)
105.9(4)
98.76(8)
Cu1-I2
Cu1-N8
Cu1-N11i
Cu2-I1
Cu2-I2
Cu2-N2
Cu2-N5
Cu3-I3
N2-Cu2-N5
N2-Cu2-I2
N5-Cu2-I2
N2-Cu2-I1
N5-Cu2-I1
I2-Cu2-I1
N12-Cu6-N10ii
N12-Cu6-I5
N10ii-Cu6-I5
N12-Cu6-I6
N10ii-Cu6-I6
I5-Cu6-I6
Cu3-I4
Cu3-N4ii
Cu3-N6
Cu4-I3
N4ii-Cu3-N6
N4ii-Cu3-I3
N6-Cu3-I3
N4ii-Cu3-I4
N6-Cu3-I4
I3-Cu3-I4
Cu4-I4
Cu4-N1iii
Cu4-N3iv
Cu5-I5
Cu5-I6
Cu5-N7ii
Cu5-N9
Cu6-I5
N3iv-Cu4-N1iii
N3iv-Cu4-I4
N1iii-Cu4-I4
N3iv-Cu4-I3
N1iii-Cu4-I3
I4-Cu4-I3
Cu6-I6
Cu6-N12
Cu6-N10ii
4
5
Cu-N1
Cu-I
1.979(3)
2.5415(8)
N1-Cu-N1i
N1-Cu-I
127.83(16)
116.09(8)
Cu1-N11
2.076(3)
N11-Cu1-I1i
121.40(9)
N1iii-Cu3-I2
N1iii-Cu3-I3
I2-Cu3-I3
109.55(10)
Cu1-I1i
Cu1-I2i
Cu1-I1
Cu2-N9ii
Cu2-I3
Cu2-I1
Cu2-I2
Cu3-N1iii
Cu3-I2
Cu3-I3
Cu3-I3iv
2.5964(7)
2.6491(7)
2.7345(9)
2.057(3)
2.5823(8)
2.6630(7)
2.8046(8)
2.035(3)
N11-Cu1-I2i
I1i-Cu1-I2i
N11-Cu1-I1
I1-Cu1-I1i
I2-Cu1-I1i
N9ii-Cu2-I3
N9ii-Cu2-I1
I3-Cu2-I1
N9ii-Cu2-I2
I3-Cu2-I2
I1-Cu2-I2
107.03(9)
108.91(3)
100.67(10)
107.06(2)
111.47(2)
116.05(10)
114.43(9)
108.37(2)
98.86(9)
110.87(10)
119.88(2)
101.20(10)
110.88(2)
102.67(3)
N1iii-Cu3-I3iv
I2-Cu3-I3iv
I3-Cu3-I3iv
2.6186(8)
2.6517(7)
2.7167(8)
115.67(2)
102.60(3)
a Symmetry transformations used to generate equivalent atoms. 3: (i) x, y + 1, z; (ii) x + 1, y, z; (iii) x + 1, y - 1, z; (iv) x, y - 1, z. 4: (i) 1 - x, y,
3
3
1
3
1
-z + /2. 5: (i) -x, 1 - y, -z; (ii) -x, 1 - y, -1 - z; (iii) -1 - x, /2 - y, /2 - z; (iv) x, /2 - y, /2 - z.
Table 3. Crystallographic Data Summary for Complexes 1-5 and pypm‚H2O
1
2
3
4
5
pypm‚H2O
formula
mol wt
cryst syst
space group
a (Å)
C28H21Cu2I2N11
892.44
triclinic
P1h
10.988(2)
12.236(3)
12.292(3)
65.459(3)
77.598(4)
85.232(4)
1468.2(6)
2
C16H12CuIN2
422.72
orthorhombic
Pccn
21.618(3)
4.2267(7)
15.212(2)
C60H44Cu6I6N12
2075.71
monoclinic
P2/c
13.624(2)
16.235(3)
30.292(5)
C15H11CuIN3
423.71
orthorhombic
Pbcn
9.040(2)
14.870(3)
10.270(2)
C9H7Cu3I3N3
728.50
monoclinic
P21/c
8.643(2)
20.034(5)
8.384(2)
C18H18N6O2
349.38
monoclinic
C2/c
38.565(8)
3.7140(7)
29.750(6)
b (Å)
c (Å)
R (deg)
â (deg)
γ (deg)
U (Å3)
Z
100.617(2)
99.846(4)
126.78(3)
1389.9(4)
4
6585.7(18)
4
1380.5(5)
4
1430.3(6)
4
3413.1(12)
8
T (K)
150(2)
3.592
6739
150(2)
3.782
8516
150(2)
4.763
14334
150(2)
3.810
7603
150(2)
10.878
12256
120(2)
0.094
23844
µ (mm-1
)
reflns collected
unique reflns (Rint
final R1 [F > 4σ(F)]
wR2 (all data)
)
4478 (0.061)
0.0359
0.0755
1614 (0.034)
0.0252
0.0571
6713 (0.071)
0.0858
0.264
1101 (0.0511)
0.0295
0.0603
3222 (0.087)
0.0229
0.0496
3929 (0.105)
0.0786
0.133
SHELXL97.19 All hydrogen atoms were placed in geometrically
calculated positions and thereafter refined using a riding model with
Uiso(H) ) 1.2Ueq(C). All non-hydrogen atoms were refined with
anisotropic displacement parameters. Other details of crystal data
and structure determination are given in Table 3. Powder X-ray
diffraction patterns were collected using a Philips X’pert θ-2θ
diffractometer with Cu KR radiation from samples mounted on flat
glass plate sample holders. Scans of approximately 50 min were
(19) Sheldrick, G. M. SHELXL97; University of Go¨ttingen: Go¨ttingen,
Germany, 1997.
6182 Inorganic Chemistry, Vol. 45, No. 16, 2006

Control of Copper(I) Iodide Architectures
Figure 1. (a) View of the Cu(I) coordination environment found in [CuI(dpt)‚MeCN]∞, 1, showing the numbering scheme used. The displacement ellipsoids
are drawn at the 50% probability level. (b) View of the ribbon structure found for [CuI(dpt)]∞. Hydrogen atoms and MeCN solvent molecules are omitted
for clarity. The symmetry code (i) correspnds to x, y + 1, z - 1.
run for each sample to assess phase purity and were run over the
range 5° e 2θ e 80° with a step size of 0.02° in 2θ and a step
time of 0.65 s. Simulated powder patterns were generated using
either APD (part of the Philips software package) or POWDER-
CELL,20 taking the final model from single-crystal structure
refinement as input.
dpt ligands from adjacent ribbons sitting above and below
the cavity within a given ribbon. However, MeCN solvent
molecules do occupy the residual space between the layers
of ribbons. It is particularly notable in the context of this
paper, and in particular for compounds 3 and 4, that the
triazine N-donors of the dpt ligand are not coordinated to
any Cu(I) centers in 1. This concurs with previously observed
complexes of the ligand dpt8a,12 and with the relatively
hindered nature and poor donor ability of its triazine
N-donors.
Results and Discussion
The ligands illustrated in Chart 1 were reacted with CuI
under a range of conditions to afford CuI-ligand coordina-
tion polymers with a variety of structures and (CuI)∞ motifs.
[CuI(dpt)‚MeCN]∞ (1). Slow diffusion of a solution of
the angular ligand dpt dissolved in CH2Cl2 into a solution
of CuI in MeCN in the L/M ratios of 1:1 and 1:2 gave dark
red crystals of the coordination polymer [CuI(dpt)‚MeCN]∞,
1. A single-crystal structure determination of 1 reveals that
each approximately tetrahedral Cu(I) center is bound by two
iodide anions and two dpt ligands (Figure 1a; see Table 1
for selected bond lengths and angles) which results in a
planar ribbon-type structure with dpt acting as a bidentate
ligand connected via [Cu2I2] rhomboid dimer cores. These
metal-iodide cores act as planar, four-connected junctions
that are joined to each other via two dpt ligands (Figure 1b).
The ribbon structure in 1 is very similar to that observed in
[CuI(bis(4-pyridyl)disulfide)]∞.7a The choice of the angular
ligand dpt incorporating a relative disposition of a 120° angle
between the pyridyl N-donors results in the formation of
cavities in 1 which are bordered by the organic ligands and
[Cu2I2] units. The distance between the centroids of the
[Cu2I2] cores is 13.26 Å, and the N‚‚‚N distance between
the nitrogens of the triazine rings across a cavity is 7.94 Å.
Although this means the cavities are large enough to
accommodate guest molecules, the packing arrangement of
the ribbons precludes the possibility of inclusion because of
Attempts to obtain bulk samples of 1 by rapid precipitation
revealed that only a reaction with a dpt and CuI in a 1:1
ratio yielded the red complex 1 (Figure 2). A reaction using
a 1:2 dpt/CuI ratio gave a brown powder which was shown
by powder X-ray diffraction (Figure 2) to be a mixture of 1
and another product. Elemental analysis indicated that the
latter was most likely to be a complex with formula [(CuI)2-
(dpt)]∞, but unfortunately, attempts to grow single crystals
have been unsuccessful thus far.
[CuI(dpb)]∞ (2). Compound 2 can be prepared either via
rapid precipitation by mixing solutions of CuI and dpb in a
1:1 stoichiometric ratio or by layering MeCN solutions of
the ligand and metal salt. Whereas the rapid precipitation
method affords a pure phase of 2, as shown by powder X-ray
diffraction, layering methods give two distinct forms. Orange
crystals of 2 are grown in the ligand-rich region of the
layering experiment, while yellow crystals appear in the
metal-rich region. Unfortunately, the yellow crystals were
not of sufficient quality or quantity to allow structural
determination of this other product. However, the observation
of the yellow phase is entirely consistent with previous
observations with other linear dipyridyl ligands where both
orange and yellow forms are commonly observed.7b In other
instances, the yellow form has been found to have a
stoichiometry of [(CuI)2L)]∞ and a structure based on CuI
(20) Nolze, G.; Kraus, W. Powder Diffr. 1998, 13, 256.
Inorganic Chemistry, Vol. 45, No. 16, 2006 6183

The´bault et al.
Figure 2. (a) The powder X-ray diffraction pattern observed from the 1:1 CuI/dpt reaction showing the observed data (black line) and the calculated pattern
from the single-crystal X-ray data for [(CuI)(dpt)‚MeCN]∞, 1 (red line). (b) The powder pattern observed from the 1:2 dpt/CuI reaction showing the observed
data (black line) and the calculated pattern from the single-crystal X-ray data for [(CuI)(dpt)‚MeCN]∞, 1 (red line), see text.
ladders linked by dipyridyl ligands to afford a two-
dimensional sheet structure.7b
distance of 4.23 Å seen between phenylene or pyridyl rings
of adjacent ligands.
The importance of the angular nature of dpt is clearly
shown by the structure of 2 formed by the linear ligand dpb.
Dpb consists of three aromatic units, but in this case the
central unit is substituted in its para positions, and so the
ligand acts as a simple linear connector. As has been
observed previously, one-dimensional (CuI)∞ chains or
ladders are typically observed with linear ligands of this
type.7b This trend is followed by 2 in which undulating two-
dimensional sheets are observed with dpb ligands linking
(CuI)∞ chains (Figure 3a) and each Cu(I) center being
coordinated by two iodides and two pyridyl donors (Figure
3b; see Table 1 for selected bond lengths and angles).
Previous observations have indicated that (CuI)∞ chains are
favored by bipyridyl ligands containing multiple aromatic
rings.7b However, despite the observation of (CuI)∞ chains
in 2, no π-π stacking interactions are observed between
adjacent dpb ligands, with a minimum centroid-centroid
[(CuI)3(dpypy)2]∞ (3) and [CuI(dpypy)]∞ (4). Compounds
3 and 4 were prepared by solvothermal methods using either
DMF or a 1:1 DMF/H2O mixture as solvent. Using this
approach, dpypy reacts with CuI to afford three distinct
crystalline products, including 3 and 4, all orange in color
and with no distinct morphological differences. A third phase
was isolated as a single crystal, but although a monoclinic
unit cell [a ) 18.544(3) Å, b ) 17.308(3) Å, and c )
14.583(2) Å, â ) 113.54(3)°] could be determined, no
chemically sensible structure solution could be obtained from
the diffraction data collected. Powder X-ray diffraction
measurements were performed upon bulk materials isolated
from the reaction between dpypy and CuI. The diffractogram
showed that the powder obtained is mostly amorphous and
that although some peaks can be identified as being due to
3 or 4, other peaks indicate the presence of other phases
that have not been isolated as single crystals.
6184 Inorganic Chemistry, Vol. 45, No. 16, 2006

Control of Copper(I) Iodide Architectures
Figure 3. (a) View of the two-dimensional sheet observed in 2 illustrating
the bridging of (CuI)∞ chains by the linear dpb ligands. (b) View of the
Cu(I) coordination environment found in 2, showing the numbering scheme
used. Displacement ellipsoids are drawn at the 50% probability level. The
symmetry codes are as follows: (i) x, y - 1, z; (ii) x, y + 1, z; (iii) -x, y
1
1
1
5
3
1
- /2, -z + /2; (iv) x + /2, 1 - y, -z + /2; (v) -x + /2, -y - /2, z +
2.
Compound 3 adopts an unusual two-dimensional bilayer
sheet that uses all three ligand N-donors of dypy (Figure
4a; see Table 1 for selected bond lengths and angles). In
each case a (CuI)2 rhomboid dimer is formed, and ribbon
structures similar to those observed in 1 are generated. These
ribbons are then linked via (CuI)2 coordination at the central
pyridyl donor unit to afford a two-dimensional structure of
linked ribbons (Figure 4b). The ligand acceptor sites of this
(CuI)2 dimeric unit are oriented such that the formation of a
bilayer structure is favored (Figure 4b). These bilayers are
then interpenetrated by an adjacent layer such that bilayers
of bilayers are formed (Figure 4c). Such interpenetrated two-
dimensional structures have been observed previously,21 but
the interpenetration of bilayer structures is significantly less
common.22 Interpenetrating layers interact via π-π stacking
interactions between pyridyl groups of dpypy ligands on
separate [CuI(dpypy)]∞ bilayers (centroid-centroid separa-
tion 3.82 Å, offset 1.72 Å).
Compound 4, [CuI(dpypy)]∞, also prepared from CuI and
dpypy under solvothermal conditions, shows an entirely
different structure to that observed in 3. In 4 each Cu(I) center
adopts a trigonal planar geometry, coordinated by two pyridyl
donors from two spatially distinct dpypy ligands and from a
nonbridging iodide ligand (see Table 2 for selected bond
lengths and angles, Figure 5). The dpypy ligands bridge Cu-
Figure 4. (a) View of the Cu(I) coordination environments found in 3,
showing the numbering schemes used. Displacement ellipsoids are drawn
at the 50% probability level. The symmetry codes are as follows: (i) x, 1
+ y, z; (ii) x - 1, y, z; (iii) x - 1, y + 1, z; (iv) x + 1, y, z; (v) x + 1, y
- 1, z; (vi) x, y - 1, z. (b) View of the bilayer structure observed in 3:
note the orientations of (CuI)2 rhomboid dimers (Cu, right hatch; N, dotted;
I, black, filled circles). (c) View of the interpenetrated bilayers observed in
3.
(21) Batten, S. R. CrystEngComm 2001, 3, 67.
(22) Sun, D. F.; Bi, W. H.; Li, X.; Cao, R. Inorg. Chem. Commun. 2004,
7, 683.
Inorganic Chemistry, Vol. 45, No. 16, 2006 6185

The´bault et al.
Figure 5. A view of 4 showing the Cu(I) coordination environment, the one-dimensional chain structure, and the atom numbering scheme. Displacement
3
ellipsoids are drawn at the 50% probability level. The symmetry codes are as follows: (i) 1 - x, y, -z + /2; (ii) -x, -y, 2 - z; (iii) 1 + x, y, z - 1.
(I) centers as a bidentate donor to generate a one-dimensional
chain structure with the central pyridyl donor of the dpypy
ligands remaining uncoordinated. Although chains are ar-
ranged in a parallel fashion in the ac plane, adjacent sheets
of parallel chains are organized such that chains in neighbor-
ing sheets are orthogonal to one another. Adjacent chains
interact via two different, but long, π-π interactions: the
first between two coordinated pyridyl rings (centroid-plane
distance ) 3.452 Å; centroid-centroid distance ) 4.069 Å),
the second between a coordinated pyridyl ring and an
uncoordinated central dpypy ring (centroid-plane distance
) 3.494 Å; centroid-centroid distance ) 4.154 Å). Although
nonbridging iodides with a trigonal planar geometry23 are
unusual for copper iodide species, this geometrical arrange-
ment is relatively common for Cu(I) complexes.
[Cu3I3(pypm)]∞ (5). Single crystals of compound 5 were
prepared using solvothermal synthetic methods by reacting
copper(I) iodide with pypm at 120 °C for 5 days in a water/
acetonitrile (1:1) solution. Attempts to prepare samples of 5
by precipitation from rapidly mixed solutions of CuI and
pypm in MeCN gave only amorphous material as evidenced
by powder X-ray diffraction.
A single-crystal structural determination of 5 reveals a
three-dimensional structure in which highly unusual (CuI)∞
sheets are pillared by pypm ligands (Figure 6a). Each
N-donor of the pypm ligand is coordinated to a Cu(I) cation
which forms part of the extended (CuI)∞ sheet structure
(Figure 6b; see Table 2 for selected bond lengths and angles).
The (CuI)∞ sheet (Figure 6c) comprises (CuI)∞ chains (green,
Figure 6c) that are cross-linked by (CuI)4 stepped cubane
tetramers (red in Figure 6c)10 to give an overall 63 net.
Although a range of (CuI)∞ structures have been reported
ranging from zero- to three-dimensional structures (see
Introduction), this type of (CuI)∞ sheet structure is highly
unusual and, to our knowledge, unprecedented. The pypm
Figure 6. (a) View of the three-dimensional structure of 5 in which (CuI)∞
ligands bridge adjacent (CuI)∞ sheets such that for a given
pypm ligand the pyrimidine group sits within a pore of one
sheet and acts as a bridge across the pore to another sheet
(Figure 7). The pyridine donor of the ligand binds to copper
centers within (CuI)∞ chains (highlighted in green in Figure
6c) on an adjacent sheet.
sheets are pillared by pypm ligands (Cu, blue; I, purple; N, blue; C, gray).
(b) View of the Cu(I) coordination environment found in 5, showing the
numbering scheme used. Displacement ellipsoids are drawn at the 50%
3
probability level. The symmetry codes are as follows: (i) -x, y + /2, -z
1
3
1
3
1
+ /2; (ii) -x, y + /2, -z - /2; (iii) x, -y + /2, z + /2; (iv) ′x - 1, -y
+
3/2, z + 1/2. (c) View of the two-dimensional 63 net observed for the
(CuI)∞ sheets in 5.
The single crystal structure of the monohydrated form of
the free ligand (pypm‚H2O) was also collected to serve as a
comparison with the structure of 5. In the structure of pypm‚
H2O each pypm molecule participates in N‚‚‚H-O hydrogen
bonding with a water molecule [H‚‚‚N ) 2.04(5) Å; O‚‚‚N
) 2.813(6) Å; O-H‚‚‚N ) 151(6)°] through the pyridine
N-atom while the pyrimidine N-donors form C-H‚‚‚N
intermolecular interactions with adjacent pyrimidine groups
[H‚‚‚N ) 2.590 Å; C‚‚‚N ) 3.517(4) Å; C-H‚‚‚N ) 163°].
Interestingly, the average dihedral angle between the pyri-
midine ring and the pyridyl ring of the pypm molecules in
(23) (a) Healy, P. C.; Pakawatchai, C.; White, A. H. J. Chem. Soc., Dalton
Trans. 1983, 1917. (b) Walsdorff, C.; Park, S. O.; Kim, J.; Heo, J.;
Park, K. N.; Oh, J.; Kim, K. J. Chem. Soc., Dalton Trans. 1999, 923.
(c) Dyason, J. C.; Engelhardt, L. M.; Healy, P. C.; Kildea, J. D.; White,
A. H. Aust. J. Chem. 1988, 41, 335.
6186 Inorganic Chemistry, Vol. 45, No. 16, 2006

Control of Copper(I) Iodide Architectures
It is clear that controlling CuI structural arrangements
remains a significant challenge to those interested in the
development of these fascinating structural arrangements and
types. The ligand geometry clearly has a significant influence,
and the synthesis of certain structural types can be targeted
with a degree of success, particularly in two-dimensional
sheet structures incorporating (CuI)∞ chains or ladders with
linear dipyridyl ligands,7b for example, compound 2. It is
also notable that the use of angular dipyridyl ligands, such
as dpt in 1, dpypy in 3, and bis(4-pyridyl)disulfide,7a favors
the formation of (CuI)2 rhomboid dimers.
The introduction of greater structural complexity and
variety into the ligands leads to more unusual structural
arrangements in the resultant complexes. This may be a result
of the (CuI)∞ oligomer/polymer accommodating the arrange-
ment of donors while providing sufficient donors, in the form
of bridging iodide anions, to satisfy the coordination require-
ments of the copper(I) cations. Thus, a range of structurally
unusual complexes have been prepared, including a 2-fold
interpenetrated bilayer structure as in 3 and an unexpected
(CuI)∞ sheet structure as in 5. These framework materials
illustrate some of the structural preferences for particular
CuI-ligand architectures with greater ligand complexity
affording more complex (CuI)∞ motifs.
Figure 7. View of the bridging by the pyrimidine group of the pypm
ligands across the (CuI)∞ sheets in compound 5 (Cu, right hatch; N, dotted;
I, black, filled circles).
pypm‚H2O is 35(3)°,24 compared with a corresponding value
of 34.0(1)° in 5. This similarity in dihedral angles between
5 and pypm‚H2O may be purely coincidence or may indicate
the possibility that the (CuI)∞ motif accommodates the
preferred ligand conformation.
Conclusions
The angular disposition of the N-donors of the ligands used
in this study exerts a defining influence on the oligomeric
or polymeric architectures adopted by the CuI complexes.
A range of oligomeric and polymeric structures of CuI are
observed, the most common being the (CuI)2 rhomboid dimer
as in compounds 1 and 3. Another common motif, (CuI)∞
chains, is observed in compound 2 which has a strong
similarity to a range of compounds observed with linear
dipyridyl ligands.7b However, the introduction of the com-
bination of different donors, that is, the combination of
pyrimidinyl and pyridyl donors in the ligand pypm, leads to
a highly unusual (CuI)∞ sheet structure that combines features
of more common chain and stepped cubane (CuI)∞ motifs.
Acknowledgment. We thank the Engineering and Physi-
cal Sciences Research Council (EPSRC) and the University
of Nottingham for funding and the EPSRC National Mass
Spectrometry Service Centre in Swansea University for mass
spectra. We are grateful to the EPSRC National Crystal-
lography Service at the University of Southampton for data
collection on pypm‚H2O. M.S. gratefully acknowledges
receipt of a Royal Society Wolfson Merit Award and of a
Royal Society Leverhulme Trust Senior Research Fellowship.
Supporting Information Available: Crystallographic data in
the form of a CIF file. This material is available free of charge via
the Internet at http://pubs.acs.org.
(24) The two independent molecules in the asymmetric unit of pypm‚H2O
exhibit pyrimidine-pyridine dihedral angles of 38.9(1) and 30.7(1)°.
IC052130K
Inorganic Chemistry, Vol. 45, No. 16, 2006 6187