Trans-[OsIII(salen)(CN)2]-: A new paramagnetic building block for the construction of molecule-based magnetic materials

Article abstract of DOI:10.1021/ic9020178

A novel dicyanoosmium(III) complex, trans-Ph₄P[Os ^III(salen)(CN)₂]* CH₂Cl₂ * H₂O (1; Ph₄ P⁺ = tetraphenylphosphonium cation, salen^2-=N, N′-ethylenebis(salicylideneaminato) dianion), has been synthesized and structurally characterized. Reactions of 1 with [Cu(Me₃tacn)(H₂O)₂](ClO₄) ₂ (Me₃tacn=1, 4, 7-trimethyl-1, 4, 7-triazacyclononane) under different conditions produce the 1-D ferromagnetic zigzag chains [Os(salen)(CN)₂]₂[Cu(Me₃tacn)] * CH ₃OH (2) and [Os(salen)(CN)₂][Cu(Me₃tacn)] * ClO₄ (3).

Full text of DOI:10.1021/ic9020178

Inorg. Chem. 2010, 49, 1607–1614 1607
DOI: 10.1021/ic9020178
trans-[OsIII(salen)(CN)2]-: A New Paramagnetic Building Block for the
Construction of Molecule-Based Magnetic Materials
Jun-Fang Guo,† Wai-Fun Yeung,† Pui-Ha Lau,† Xiu-Teng Wang,‡ Song Gao,*,‡ Wing-Tak Wong,§
Stephen Sin-Yin Chui,§ Chi-Ming Che,*,§ Wai-Yeung Wong, and Tai-Chu Lau*,†
†Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong
Kong, People’s Republic of China, ‡Beijing National Laboratory for Molecular Sciences, State Key Laboratory
of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking
University, Beijing 100871, People’s Republic of China, §Department of Chemistry, The University of Hong
Kong, Pokfulam Road, Hong Kong, People’s Republic of China, and Department of Chemistry, Hong Kong
Baptist University, Waterloo Road, Hong Kong, People’s Republic of China
Received October 13, 2009
A novel dicyanoosmium(III) complex, trans-Ph4P[OsIII(salen)(CN)2] CH2Cl2 H2O (1; Ph4Pþ = tetraphenylpho-
3
3
sphonium cation, salen2- =N,N0-ethylenebis(salicylideneaminato) dianion), has been synthesized and structurally
characterized. Reactions of 1 with [Cu(Me3tacn)(H2O)2](ClO4)2 (Me3tacn=1,4,7-trimethyl-1,4,7-triazacyclononane)
under different conditions produce the 1-D ferromagnetic zigzag chains [Os(salen)(CN)2]2[Cu(Me3tacn)] CH3OH (2)
3
and [Os(salen)(CN)2][Cu(Me3tacn)] ClO4 (3).
3
Introduction
[MIV/V(CN)8]4-/3- (M = MoIV/V WIV/V NbIV),1,3
, ,
[ReII(triphos)(CN)3]-,4 [RuIII(ox)3]3- (ox = oxalato),5
Paramagnetic 4d and 5d metal ions have been recognized
recently as very appealing spin carriers for the preparation of
molecular magnetic materials, since 4d and 5d orbitals are
more diffuse than 3d orbitals and so enhanced magnetic
interactions may be expected.1 However, examples of poly-
nuclear complexes based on 4d or 5d building blocks are
rather limited. We note that 3d-4d and 3d-5d coordination
polymers in the field of molecular magnetism are mostly
(3) See, for example: (a) Chibotaru, L. F.; Mironov, V. S.; Ceulemans, A.
Angew. Chem., Int. Ed. 2001, 40, 4429–4433. (b) Arimoto, Y.; Ohkoshi, S.-i.;
Zhong, Z.-J.; Seino, H.; Mizobe, Y.; Hashimoto, K. J. Am. Chem. Soc. 2003, 125,
9240–9241. (c) Kashiwagi, T.; Ohkoshi, S.-i.; Seino, H.; Mizobe, Y.; Hashimoto,
K. J. Am. Chem. Soc. 2004, 126, 5024–5025. (d) Song, Y.; Zhang, P.; Ren,
X.-M.; Shen, X.-F.; Li, Y.-Z.; You, X.-Z. J. Am. Chem. Soc. 2005, 127, 3708–
3709. (e) Sieklucka, B.; Podgajny, R.; Przychodzen, P.; Korzeniak, T. Coord.
Chem. Rev. 2005, 249, 2203–2221. (f ) Przychodzen, P.; Korzeniak, T.; Podgajny,
R.; Sieklucka, B. Coord. Chem. Rev. 2006, 250, 2234–2260. (g) Visinescu, D.;
Desplanches, C.; Imaz, I.; Bahers, V.; Pradhan, R.; Villamena, F. A.; Guionneau,
P.; Sutter, J.-P. J. Am. Chem. Soc. 2006, 128, 10202–10212. (h) Atanasov, M.;
Comba, P.; Lampeka, Y. D.; Linti, G.; Malcherek, T.; Miletich, R.; Prikhod'ko,
A. I.; Pritzkow, H. Chem. Eur. J. 2006, 12, 737–748. (i) Lim, J. H.; Yoon, J. H.;
Kim, H. C.; Hong, C. S. Angew. Chem., Int. Ed. 2006, 45, 7424–7426. ( j) Prins,
F.; Pasca, E.; Jos de Jongh, L.; Kooijman, H.; Spek, A. L.; Tanase, S. Angew.
Chem., Int. Ed. 2007, 46, 6081–6084. (k) Wang, Z.-X.; Li, X.-L.; Liu, B.-L.;
Tokoro, H.; Zhang, P.; Song, Y.; Ohkoshi, S.-i.; Hashimoto, K.; You, X.-Z. Dalton
Trans. 2008, 16, 2103–2106. (l) Podgajny, R.; Pinkowicz, D.; Korzeniak, T.;
Nitek, W.; Rams, M.; Sieklucka, B. Inorg. Chem. 2007, 46, 10416–10425. (m)
Arai, M.; Kosaka, W.; Matsuda, T.; Ohkoshi, S.-i. Angew. Chem., Int. Ed. 2008,
47, 6885–6887. (n) Chelebaeva, E.; Larionova, J.; Guari, Y.; Ferreira, R. A. S.;
Carlos, L. D.; Almeida, P.; Filipe, A.; Trifonov, A.; Guerin, C. Inorg. Chem. 2009,
48, 5983–5995.
constructed from precursors such as [MoIII(CN)7]4- 2
,
*To whom correspondence should be addressed. E-mail: bhtclau@cityu.
edu.hk (T.-C.L.).
(1) Visinescu, D.; Desplanches, C.; Imaz, I.; Bahers, V.; Pradhan, R.;
Villamena, F. A.; Guionneau, P.; Sutter, J.-P. J. Am. Chem. Soc. 2006, 128,
10202–10212.
(2) (a) Larionova, J.; Sanchiz, J.; Golhen, S.; Ouahab, L.; Kahn, O. Chem.
Commun. 1998, 953–954. (b) Sra, A. K.; Andruh, M.; Kahn, O.; Golhen, S.;
Ouahab, L.; Yakhmi, J. V. Angew. Chem., Int. Ed. 1999, 38, 2606–2609. (c)
ꢀ
Larionova, J.; Clerac, R.; Sanchiz, J.; Kahn, O.; Golhen, S.; Ouahab, L. J. Am.
Chem. Soc. 1998, 120, 13088–13095. (d) Larionova, J.; Kahn, O.; Golhen, S.;
ꢀ
Ouahab, L.; Clerac, R. J. Am. Chem. Soc. 1999, 121, 3349–3356. (e) Larionova,
ꢀ
ꢀ
J.; Clerac, R.; Donnadieu, B.; Guerin, C. Chem. Eur. J. 2002, 8, 2712–2716. (f )
ꢁ
Tanase, S.; Tuna, F.; Guionneau, P.; Maris, T.; Rombaut, G.; Mathoniere, C.;
Andruh, M.; Kahn, O.; Sutter, J.-P. Inorg. Chem. 2003, 42, 1625–1631. (g)
Mironov, V. S.; Chibotaru, L. F.; Ceulemans, A. J. Am. Chem. Soc. 2003, 125,
9750–9760. (h) Le Goff, X. F.; Willemin, S.; Coulon, C.; Larionova, J.;
(4) (a) Schelter, E. J.; Prosvirin, A. V.; Dunbar, K. R. J. Am. Chem. Soc.
2004, 126, 15004–15005. (b) Schelter, E. J.; Prosvirin, A. V.; Reiff, W. M.;
Dunbar, K. R. Angew. Chem., Int. Ed. 2004, 43, 4912–4915. (c) Palii, A. V.;
Ostrovsky, S. M.; Klokishner, S. I.; Tsukerblat, B. S.; Schelter, E. J.; Prosvirin,
A. V.; Dunbar, K. R. Inorg. Chim. Acta 2007, 360, 3915–3924. (d) Schelter, E. J.;
Karadas, F.; Avendano, C.; Prosvirin, A. V.; Wernsdorfer, W.; Dunbar, K. R.
J. Am. Chem. Soc. 2007, 129, 8139–8149.
ꢀ
Donnadieu, B.; Clerac, R. Inorg. Chem. 2004, 43, 4784–4786. (i) Chibotaru,
L. F.; Hendrickx, M. F. A.; Clima, S.; Larionova, J.; Ceulemans, A. J. Phys.
Chem. A 2005, 109, 7251–7257. ( j) Milon, J.; Daniel, M.-C.; Kaiba, A.;
Guionneau, P.; Brandes, S.; Sutter, J.-P. J. Am. Chem. Soc. 2007, 129, 13872–
13878. (k) Gillon, B.; Goujon, A.; Willemin, S.; Larionova, J.; Desplanches, C.;
(5) Larionova, J.; Mombelli, B.; Sanchiz, J.; Kahn, O. Inorg. Chem. 1998,
37, 679–684.
ꢀ
ꢀ
Ruiz, E.; Andre, G.; Stride, J. A.; Guerin, C. Inorg. Chem. 2007, 46, 1090–1099.
r
2010 American Chemical Society
Published on Web 01/12/2010
pubs.acs.org/IC

1608 Inorganic Chemistry, Vol. 49, No. 4, 2010
Guo et al.
[Ru2(O2CR)4]þ,6 [RuIII(acac)2(CN)2]-,7 and [RuIII(salen)-
(CN)2]-,7b,8 which exhibit various interesting magnetic
properties.
Although there have been a number of reports on magnetic
materials based on paramagnetic ruthenium centers, there
are only two examples of magnetic materials containing
paramagnetic osmium centers.9 Dunbar reported the penta-
Preparations. OsII(PPh3)3Cl2. A mixture of (NH4)2[OsCl6]
(0.5 g, 1.14 mmol) and PPh3 (2.1 g, 8.0 mmol) in 35 mL of a 5:2 2-
methoxyethanol-water solvent mixture was refluxed for 3 h
under argon. After the mixture was cooled to room temperature,
the resulting green solid was collected by filtration, washed
thoroughly with water and then methanol and diethyl ether,
and dried in air. Yield: 1.1 g (92%).
OsIII(salen)(PPh3)Cl. H2salen (0.335 g, 1.25 mmol), triethyl-
amine (0.5 g, 5 mmol), and Os(PPh3)3Cl2 (1.05 g, 1.0 mmol) were
refluxed in 50 mL of ethanol for 3 h. After it was cooled to room
temperature, the solution was filtered and the filtrate was con-
centrated to about 5 mL. Addition of diethyl ether (50 mL)
produced a dark brown precipitate which was collected by
filtration and washed with water and then diethyl ether. Yield:
0.55 g (58%). Anal. Calcd for C34H29N2O2PClOs: C, 54.14; H,
3.88; N, 3.71. Found: C, 54.02; H, 4.21; N, 3.62.
nuclear complex {[Ni(tmphen)2]3[Os(CN)6]2} 6CH3CN and
3
the Prussian blue analogue Ni3[Os(CN)6]2 4H2O con-
3
structed from [Os(CN)6]3-. Both compounds exhibit ferro-
magnetic coupling between NiII and OsIII.9b Herein we report
the synthesis and characterization of a new paramagnetic
dicyanoosmate(III) building block, trans-[Os(salen)(CN)2]-
(1; salen2-=N,N0-ethylenebis(salicylideneaminato) dianion).
Reactions of 1 with [Cu(Me3tacn)(H2O)2](ClO4)2 (Me3tacn=
1,4,7-trimethyl-1,4,7-triazacyclononane) under different
conditions produce the 1-D ferromagnetic zigzag chains
trans-Ph4P[OsIII(salen)(CN)2] CH2Cl2 H2O (1). OsIII(salen)-
3
3
(PPh3)Cl (200 mg, 0.265 mmol) was refluxed with KCN (200 mg,
3.07 mmol) in 40 mL of ethanol for 4 h. The dark brown solution
was evaporated to dryness and the residue then dissolved in 5 mL
of water. Addition of Ph4PCl (99 mg, 0.265 mmol) to the aqueous
solution produced a dark brown precipitate which was collected,
washed with water, and dried in vacuo. Well-defined dark brown
block crystals were obtained by carefully layering diethyl ether
over a CH2Cl2 solution of the product at room temperature for
about 1 week. Yield: 72 mg (32%). Anal. Calcd for C43H38-
Cl2N4O3OsP:C, 54.32;H, 4.03; N, 5.89. Found:C, 54.35; H, 4.20;
N, 5.92. IR (KBr): ν(CtN) 2084(s) cm-1. ESI/MS: m/z 510
[OsIII(salen)(CN)2]-.
[Os(salen)(CN)2]2[Cu(Me3tacn)] CH3OH (2) and [Os(salen)-
3
(CN)2][Cu(Me3tacn)] ClO4 (3).
3
Experimental Section
Materials and Reagents. All chemicals and solvents were of
reagent grade and were used as received. [Cu(Me3tacn)-
(H2O)2](ClO4)2 was synthesized according to a literature meth-
od.10 OsII(PPh3)3Cl2 was synthesized by an improved literature
procedure.11 OsIII(salen)(PPh3)Cl and 1 were synthesized by a
method similar to that for Bu4N[Ru(salen)(CN)2].7b,12
[Os(salen)(CN)2]2[Cu(Me3tacn)] CH3OH (2). [Cu(Me3tacn)-
3
Instrumentation. IR spectra were recorded as KBr pellets on a
Nicolet Avatar 360 FT-IR spectrophotometer at 4 cm-1 resolu-
tion. Elemental analyses were done on an Elementar Vario EL
analyzer. Electrospray ionization mass spectra (ESI/MS) were
obtained on a PE SCIEX API 365 mass spectrometer. Cyclic
voltammetry was performed with a PAR Model 273 potentio-
stat using a glassy-carbon working electrode, a Ag/AgNO3
(0.1 M in CH2Cl2) reference electrode, and a Pt-wire counter
electrode with ferrocene (Cp2Fe) as the internal standard.
Magnetic measurements were performed on a Quantum Design
MPMS XL-5 SQUID system. Background corrections were
done by experimental measurements on the sample holder.
The experimental susceptibilities were corrected for the dia-
magnetism of the constituent atoms (Pascal’s tables).
(H2O)2](ClO4)2 (11 mg, 0.023 mmol) was dissolved in 2 mL of
DMF in a test tube. 1 (20 mg, 0.023 mmol) dissolved in 8 mL of
methanol was carefully layered above the DMF solution. Well-
defined dark brown block crystals of 2 were obtained after
leaving the test tube undisturbed at room temperature for about
1 week. Yield: 3 mg (21%). Anal. Calcd for C46H53CuN11O5Os2:
C, 43.03; H, 4.16; N, 12.00. Found: C, 42.86; H, 4.24; N, 11.93.
IR (KBr): ν(CtN) 2137, 2097 cm-1
.
[Os(salen)(CN)2][Cu(Me3tacn)] ClO4 (3). Crystals of 3 were
3
grown by slow interdiffusion in an H-shaped tube with 1
(33 mg, 0.038 mmol) in CH3OH at one arm and [Cu(Me3tacn)-
(H2O)2](ClO4)2 (18 mg, 0.038 mmol) in DMF at the other.
Brown microcrystals of 3 were formed on standing at
room temperature after 3 days. Yield: 18 mg (57%). Anal.
Calcd for C27H35ClCuN7O6Os: C, 38.48; H, 4.18; N, 11.63.
Found: C, 38.11; H, 4.55; N, 11.60. IR (KBr): ν(CtN)
(6) (a) Cotton, F. A.; Kim, Y.; Ren, T. Inorg. Chem. 1992, 31, 2723–2726.
(b) Beck, E. J.; Drysdale, K. D.; Thompson, L. K.; Li, L.; Murphy, C. A.; Aquino,
M. A. S. Inorg. Chim. Acta 1998, 279, 121–125. (c) Liao, Y.; Shum, W. W.;
Miller, J. S. J. Am. Chem. Soc. 2002, 124, 9336–9337. (d) Vos, T. Y.; Liao, Y.;
Shum, W. W.; Her, J.-H.; Stephens, P. W.; Reiff, W. M.; Miller, J. S. J. Am. Chem.
Soc. 2004, 126, 11630–11639. (e) Yoshioka, D.; Mikuriya, M.; Handa, M. Chem.
Lett. 2002, 1044–1045. (f ) Vos, T. E.; Miller, J. S. Angew. Chem., Int. Ed. 2005,
44, 2416–2419. (g) Liu, W.; Nfor, E. N.; Li, Y.-Z.; Zuo, J.-L.; You, X.-Z. Inorg.
Chem. Commun. 2006, 9, 923–925.
(7) (a) Yeung, W. F.; Man, W. L.; Wong, W. T.; Lau, T. C.; Gao, S.
Angew. Chem., Int. Ed. 2001, 40, 3031–3033. (b) Yeung, W. F.; Lau, P. H.; Lau,
T. C.; Wei, H. Y.; Sun, H. L.; Gao, S.; Chen, Z. D.; Wong, W. T. Inorg. Chem.
2005, 44, 6579–6590. (c) Yeung, W. F.; Lau, T. C.; Wang, X. Y.; Gao, S.; Szeto, L.;
Wong, W. T. Inorg. Chem. 2006, 45, 6756–6760. (d) Toma, L. M.; Toma, L. D.;
2115 cm-1
.
Caution! Perchlorate salts of metal complexes with organic
ligands are potentially explosive and should be handled in small
quantities (<50 mg) with care.
X-ray Crystallography. Measurements for compounds 1 and
2 were made on a Bruker SMART CCD diffractometer with
˚
graphite-monochromated Mo KR radiation (λ =0.710 73 A).
The structures were solved by direct methods (SHELXS97)13
and expanded using Fourier techniques. All non-hydrogen
atoms were refined anisotropically. All H atoms were refined
using a riding model with Uiso(H)=1.2Ueq(carrier).
X-ray Powder Diffraction. X-ray powder diffraction data of 3
were collected on a Bruker ADVANCE D8 diffractometer
equipped with a motorized sample spinning stage. Intensity
data were collected using the step-counting method (step size
0.02°), in continuous mode, in the 5 e 2θ e 70° range. Lattice
parameters were determined by indexing the first 20 diffraction
maxima within 5-20° (2θ) using the program DICVOL04.14
The intensities of 132 Bragg diffraction peaks were extracted by
ꢀ
Delgado, F. S.; Ruiz-Perez, C.; Sletten, J.; Canod, J.; Clemente-Juan, J. M.; Lloret,
F.; Julve, M. Coord. Chem. Rev. 2006, 250, 2176–2193.
(8) (a) Duimstra, J. A.; Stern, C. L.; Meade, T. J. Polyhedron 2006, 25,
2705–2709. (b) Yoon, J. H.; Yoo, H. S.; Kim, H. C.; Yoon, S. W.; Suh, B. J.; Hong,
C. S. Inorg. Chem. 2009, 48, 816–818.
(9) (a) Albores, P.; Slep, L. D.; Baraldo, L. M.; Baggio, R.; Garland,
M. T.; Rentschler, E. Inorg. Chem. 2006, 45, 2361–2363. (b) Hilger, M. G.;
Shatruk, M.; Prosvirin, A.; Dunbar, K. R. Chem. Commun. 2008, 5752–5754.
€
(10) Fry, F. H.; Fischmann, A. J.; Belousoff, M. J.; Spiccia, L.; Brugger, J.
Inorg. Chem. 2005, 44, 941–950.
€
(11) Hoffman, P. R.; Caulton, K. G. J. Am. Chem. Soc. 1975, 97, 4221–
4228.
(13) Sheldrick, G. M. SHELX-97; University of Gottingen, Gottingen,
Germany, 1997.
(12) Leung, W.-H.; Che, C.-M. Inorg. Chem. 1989, 28, 4619–4622.
(14) Boultif, A.; Louer, D. J. Appl. Crystallogr. 2004, 37, 724–731.

Article
Inorganic Chemistry, Vol. 49, No. 4, 2010 1609
˚
Table 1. Summary of Crystallographic Data for 1 and 2
Table 2. Selected Bond Lengths (A) and Angles (deg) for 1
N1-Os1
N2-Os1
O1-Os1
O2-Os1
2.004(3)
1.996(3)
2.032(3)
2.031(3)
C17-Os1
C18-Os1
C17-N3
C18-N4
2.081(4)
2.070(4)
1.148(6)
1.150(6)
1
2
formula
C43H38Cl2N4O3OsP
950.84
C46H53CuN11O5Os2
1283.93
formula mass (amu)
cryst syst
space group
triclinic
P1 (No. 2)
10.3519(6)
12.8204(8)
15.8082(9)
110.23(0)
93.36(0)
95.21(0)
1951.33(20)
2
monoclinic
P21/c (No. 14)
16.854(2)
13.4332(17)
21.843(3)
90
N2-Os1-N1
N2-Os1-O2
N1-Os1-O2
N2-Os1-O1
N1-Os1-O1
O2-Os1-O1
N2-Os1-C18
N1-Os1-C18
N4-C18-Os1
83.25(12)
91.63(11)
174.64(11)
174.32(11)
91.98(10)
93.22(9)
85.49(12)
91.96(12)
175.30(33)
O2-Os1-C18
O1-Os1-C18
N2-Os1-C17
N1-Os1-C17
O2-Os1-C17
O1-Os1-C17
C18-Os1-C17
N3-C17-Os1
89.18(11)
91.61(11)
93.59(12)
87.15(12)
91.63(11)
89.23(11)
178.79(14)
176.85(33)
˚
a (A)
˚
b (A)
˚
c (A)
R (deg)
β (deg)
γ (deg)
109.49(0)
90
3
˚
V (A )
Z
4662.04(100)
4
1.829
Dcalcd (g cm-3
T (K)
)
1.618
173(2)
a
296(2)
5.948
˚
Table 3. Selected Bond Lengths (A) and Angles (deg) for 2
μ (mm-1
F(000)
)
3.491
946
8929/0/222
Os1-N6
Os1-N5
Os1-O2
Os1-O1
Os1-C1
Os1-C2
Cu1-N1
Cu1-N9
Cu1-N3
N1-C1i
N3-C3
1.998(3)
2.003(4)
2.023(3)
2.035(3)
2.048(4)
2.060(4)
2.000(3)
2.079(4)
2.169(4)
1.151(5)
1.148(5)
Os2-N7
Os2-N8
Os2-O3
Os2-O4
Os2-C4
Os2-C3
Cu1-N10
Cu1-N11
Cu1-N2
N2-C2
2.002(4)
2.006(4)
2.030(3)
2.042(4)
2.066(5)
2.068(5)
2.208(4)
2.210(4)
2.224(4)
1.155(6)
1.146(6)
2508
10 612/0/587
no. of data/restraints/
params
GOF on F2
1.016
0.030, 0.073
0.032, 0.074
1.010
0.0576, 0.0255
0.0404, 0.0638
R1, wR2 (I > 2σ(I))
R1, wR2 (all data)
a Pawley fit algorithm.15 The structure solution was obtained by
global optimization based on simulated annealing (SA) using
the program DASH 3.1.16 The input model for structure solu-
tion calculation was taken from the partial crystal structures of
trans-[Os(salen)(SPh)2]17 and [(pzTp)2(Me3tacn)3Cu3Fe2(CN)6]-
(ClO4)4].18 The input model was manually constructed by using
the two fragments [Os(salen)(CN)] and[Cu(Me3tacn)(CN)] using
the molecular graphics suite program XP (SHELXTL version
6.14, Bruker AXS, 2000-2003). The structure of this chain
structure was solved. Structural refinement on this model was
performed using GSAS/EXPGUI software.19
N4-C4
N6-Os1-N5
N6-Os1-O2
N5-Os1-O2
N6-Os1-O1
N5-Os1-O1
O2-Os1-O1
N6-Os1-C1
N5-Os1-C1
O2-Os1-C1
O1-Os1-C1
N6-Os1-C2
N5-Os1-C2
O2-Os1-C2
O1-Os1-C2
C1-Os1-C2
N1-Cu1-N9
N1-Cu1-N3
N9-Cu1-N3
N1-Cu1-N10
N9-Cu1-N10
N3-Cu1-N10
N1-Cu1-N11
N9-Cu1-N11
C1i-N1-Cu1
C2-N2-Cu1
C3-N3-Cu1
82.47(13)
92.06(12)
172.13(12)
173.00(11)
90.66(12)
94.91(11)
86.17(14)
83.15(13)
90.87(13)
94.34(13)
87.47(14)
97.16(13)
88.21(13)
92.11(13)
173.54(15)
172.81(14)
91.00(14)
91.18(14)
90.99(14)
81.97(14)
95.88(14)
94.52(14)
83.01(14)
157.17(29)
168.72(31)
166.29(37)
N7-Os2-N8
N7-Os2-O3
N8-Os2-O3
N7-Os2-O4
N8-Os2-O4
O3-Os2-O4
N7-Os2-C4
N8-Os2-C4
O3-Os2-C4
O4-Os2-C4
N7-Os2-C3
N8-Os2-C3
O3-Os2-C3
O4-Os2-C3
C4-Os2-C3
N3-Cu1-N11
N10-Cu1-N11
N1-Cu1-N2
N9-Cu1-N2
N3-Cu1-N2
N10-Cu1-N2
N11-Cu1-N2
N1ii-C1-Os1
N2-C2-Os1
N3-C3-Os2
N4-C4-Os2
82.90(16)
92.10(14)
174.89(14)
175.01(14)
92.13(14)
92.87(11)
87.73(16)
90.91(18)
90.00(17)
91.91(15)
92.13(16)
88.76(16)
90.33(15)
88.20(15)
179.65(19)
173.84(14)
81.32(13)
92.02(12)
94.71(13)
92.92(13)
170.65(13)
89.63(13)
166.84(33)
173.09(33)
175.94(41)
175.37(47)
Results and Discussion
Synthesis, Characterization, and Structures. Crystallo-
graphic data for compounds 1 and 2 are given in Table 1
and selected bond lengths and angles in Tables 2 and 3,
respectively.
trans-Ph4P[OsIII(salen)(CN)2] CH2Cl2 H2O
(1).
3
3
Compound 1 was prepared by the reaction of KCN with
trans-[Os(salen)(PPh3)Cl], similar to that for trans-Bu4N-
[Ru(salen)(CN)2].7b,12 The IR spectrum shows a strong
ν(CtN) stretch at 2084 cm-1. The electrospray ionization
mass spectrometry (ESI/MS) of a methanolic solution of
1 (Figure S1, Supporting Information) in the anionic
mode shows a peak at m/z 510, which is due to the parent
ion [Os(salen)(CN)2]-. There is an excellent agreement
between the calculated and experimental isotopic distri-
bution patterns.
a Symmetry code: (i) 2 - x, 1 - y, 1 - z.
The cyclic voltammogram of 1 in CH2Cl2 [0.1 M (Bu4N)-
PF6] (Figure 1) shows two reversible waves at -0.15 and
-1.47 V (vs Cp2Feþ/0), which are assigned to the OsIV/OsIII
and the OsIII/OsII couples, respectively. These electro-
chemical data indicate that [Os(salen)(CN)2]- is reasonably
stable with respect to oxidation and reduction.
(15) Pawley, G. S. J. Appl. Crystallogr. 1981, 14, 357–361.
(16) David, W. I.; Shankland, F. K.; van de Streek, J.; Pidcock, E.;
Motherwell, W. D. S.; Cole, J. C. J. Appl. Crystallogr. 2006, 39, 910–915.
(17) Che, C. M.; Cheng, W. K.; Mak, T. C. W. Inorg. Chem. 1986, 25, 703–
706.
(18) Gu, Z. G.; Liu, W.; Yang, Q. F.; Zhou, X. H.; Zuo, J. L.; You, X. Z.
Inorg. Chem. 2007, 46, 3236–3244.
(19) (a) Larson, A. C.; Von Dreele, R. B.Los Alamos National Laboratory
Report LAUR 86-748, 2004. (b) Toby, B. H. J. Appl. Crystallogr. 2001, 34,
210–213.
Figure 1. Cyclic voltammogram of 1 in CH2Cl2.

1610 Inorganic Chemistry, Vol. 49, No. 4, 2010
Guo et al.
The X-ray structure of the anion of 1 is shown in
The reaction of 1 with [Cu(Me3tacn)(H2O)2](ClO4)2
in a CH3OH/DMF solution using a layering technique
produces 2 as dark brown block crystals. On the other
hand, the same reaction carried out using an inter-
diffusion technique in an H tube produces 3 as brown
microcrystals. The IR spectrum of 1 shows a νCN stretch
at 2084 cm-1, whereas 2 shows two νCN stretches at
2137 and 2097 cm-1 and 3 shows a νCN stretch at
Figure 2. The asymmetric unit consists of one [OsIII
-
(salen)(CN)2]- anion, one Ph4Pþ, one CH2Cl2, and one
H2O molecule. The osmium(III) center has a distorted-
octahedral geometry and is coordinated to the two oxy-
gen and two nitrogen atoms of salen in a planar manner,
and the two cyanide groups are trans. The average Os-O,
Os-N, Os-C and CtN bond lengths are 2.031(3),
2.000(3), 2.076(4), and 1.149(6) A, respectively. The
2115 cm-1
.
˚
C18-Os1-C17 angle is close to linear (178.79(14)°).
[Os(salen)(CN)2]2[Cu(Me3tacn)] CH3OH (2). Com-
3
pound 2 exists as a 1-D neutral zigzag polymer
(Figure 3). The asymmetric unit consists of one [Cu-
(Me3tacn)]2þ and two [Os(salen)(CN)2]- ions. The
[Os(salen)(CN)2]- ions are in two different environ-
ments. One type of [Os(salen)(CN)2]- is connected to
two [Cu(Me3tacn)]2þ units using its trans cyano groups
to form a zigzag chain with a N1-Cu1-N2 bond angle
of 92.02(12)°. The other type of [Os(salen)(CN)2]- ion is
connected to [Cu(Me3tacn)]2þ using only one of its
cyano groups. The CuII is hexacoordinated to six nitro-
gen atoms, three from the Me3tacn ligand and three
from bridging cyanide ligands, in a slightly distorted
octahedral geometry. The average Cu-N(Me3tacn)
Figure 2. ORTEP view of [Os(salen)(CN)2]- (the anion of 1) with the
atomic numbering scheme (30% probability).
˚
˚
(2.166 A) and Cu-N(cyano) bond lengths (2.131 A) in
Figure 3. (a) ORTEP view of 2 with the atom-labeling scheme (30% probability). (b) Crystal-packing diagram of 2 projected down the b axis with the axes
labeled. Hydrogen atoms and methanol molecules are omitted for clarity.

Article
Inorganic Chemistry, Vol. 49, No. 4, 2010 1611
compound
2
are slightly longer than those in
Magnetic Properties. Compound 1. The molar mag-
netic susceptibility data of compound 1 indicate an
unusually strong temperature-independent Van Vleck
paramagnetism (temperature-independent paramagne-
sitm, TIP) of 2.55 ꢀ 10-3 cm3 mol-1. After this TIP value
was subtracted, the molar magnetic susceptibility in the
temperature range 30-300 K of 1 obey the Curie-Weiss
law (χM =C/(T - Θ)], with C=0.45 cm3 mol-1 K and
Θ=-0.55 K (Figure 5). The C value is comparable to that
of trans-Bu4N[Ru(salen)(CN)2] (0.414 cm3 mol-1 K) and
is near that of the low-spin (t2g)5 configuration with
S = 1/2.7b The field dependence magnetization of 1 at
2.0 K is shown in the inset to Figure 5; the M value at
50 kOe is 1.02 Nβ mol-1, consistent with the expected
saturation value for a S=1/2 state with g=2.0.
[Tp2(Me3tacn)3Cu3Fe2(CN)6](ClO4)4 2H2O (Cu-N-
3
20
˚
˚
(Me3tacn)=2.10 A, Cu-N(cyano) = 1.98 A). The
Cu-NtC units are bent, with angles of 157.17(29),
166.29(37), and 168.72(31)° separately. The OsIII is also
in a distorted-octahedral geometry: the salen ligand
occupies the equatorial positions, and the two cyanide
ligands are at the axial sites. The bond distances in each
[Os(salen)(CN)2]- unit (Os-O = 2.023(3)-2.042(4) A;
˚
˚
Os-N=1.998(3)-2.006(4) A; Os-C=2.048(4)-2.068-
˚
˚
(5) A and CtN = 1.146(6)-1.155(6) A) are similar to
those found in 1. The Os-CtN angles are bent with
values of 166.84(33), 173.09(33), and 175.94(41)° for
bridging and 175.37(47)° for terminal cyano groups. A
classical hydrogen bonding interaction exists between
the methanol solvate and one of the phenoxy oxygens
Compound 2. The temperature dependence of the mag-
netic susceptibility of 2 was measured in the range of 2-300
K under an external magnetic field of 3 kOe (Figure 6). The
molar magnetic susceptibility data of 2 also indicate an
unusually strong temperature-independent Van Vleck
paramagnetism (TIP) of 2.87 ꢀ 10-3 cm3 mol-1. The
χMT value at room temperature is 1.36 cm3 mol-1 K, which
is larger than the spin-only value of 1.125 cm3 mol-1 K for
one CuII with S=1/2 and two OsIII centers with S=1/2.
When the temperature is lowered, the χMT value increases
smoothly and attains a maximum value of 1.94 cm3 mol-1
K at 5 K; it then decreases sharply and reaches a value of
1.78 cm3 mol-1 K at 2.0 K. After the TIP value is
subtracted, the molar magnetic susceptibility above 30 K
obeys the Curie-Weiss law, χM=C/(T - Θ), with a Curie
constant C=1.33 cm3 mol-1 K and a Weiss constant Θ=
þ3.96 K. The positive Θ value and the increasing χMT
above 5 K indicate typical ferromagnetic coupling between
OsIII and CuII in 2 through a cyano bridge. The abrupt
decrease at low temperature may be due to the antiferro-
magnetic interactions between CuOs chains and/or the field
saturation effect. The magnetization of this compound per
[CuOs2] unit reaches a value of 2.62 Nβ mol-1 at 2.0 K and
50 kOe external field (Figure 5 inset), which is slightly lower
than the expected saturation value of 3.0 Nβ for the sum of
(O1) of the salen ligand. The intramolecular Cu Os
˚
distances are 5.3319(4) and 5.3880(5) A. The shortest
3 3 3
intrachain Os Os and Cu Cu separations are
˚
3 3 3
3 3 3
7.09679(19) and 10.0583(6) A, respectively, while the
shortest interchain Os Os and Cu Cu distances are
3 3 3
3 3 3
˚
8.0055(2) and 7.3402(3) A, respectively.
[Os(salen)(CN)2][Cu(Me3tacn)] ClO4 (3). Since the
3
crystals of 3 were too small for single-crystal X-ray
diffraction, the structure was solved by using X-ray
powder diffraction data. The 1-D structure of 3 was
confirmed by successful Rietveld refinement analysis of
the powder diffraction data. The graphical plot of the
final refinement cycle is shown in Figure 4a, and the
results are given in Table 4. The structure of 3 is shown in
Figure 4b, and selected bond lengths and bond angles are
summarized in Table 5. Each [Os(salen)(CN)2]- unit is
connected to two [Cu(Me3tacn)]2þ units using its trans
cyano groups to form a zigzag chain with a N4-Cu1-N3
bond angle of 79.08°. The perchlorate anions are situated
between the polymeric chains. Each CuII center is penta-
coordinated to five nitrogen atoms, three from Me3tacn
and two from cyano groups, in a distorted-square-pyr-
˚
amidal geometry. The average Cu-N(Me3tacn) (2.095 A)
˚
and Cu-N(cyano) bond lengths (2.107 A) in compound 3
are slightly shorter than those in compound
2
two OsIII and one CuII magnetic moments (ST =2SOs
þ
˚
˚
(Cu-N(Me3tacn)=2.166 A, Cu-N(cyano)=2.131 A).
The Cu-NtC units are virtually linear (178.62(14),
179.63(14)°). The OsIII is in a distorted-octahedral geo-
metry: the salen ligand occupies the equatorial positions,
and the two cyanide ligands are at the axial sites. The
bond distances in each [Os(salen)(CN)2]- unit (Os-O=
SCu=3/2;MS=gSTNβ). The field-dependence magnetization
has also been analyzed using Brillouin functions with S=1/2.
The experimental M - H curve is above the Brillouin
function curve below 24 kOe, which suggests ferromagnetic
coupling between OsIII and CuII ions.
To evaluate the value of the exchange constants of 2, we
used an approximate approach similar to that for 1-D,
2-D, and quasi-2D complexes.21 Cyanide bridges between
CuII and OsIII were regarded equal, since the bridging
modes through C1N1, C2N2, and C3N3 were almost the
same. Therefore, the 1-D chain can be treated as the
repeating unit of Os2Cu trimers with the same intratrimer
˚
˚
2.001(2)-2.007(3) A; Os-N = 1.984(3)-2.000(2) A;
˚
Os-C = 2.028(2)-2.045(2) A) are comparable to those
found in 2 and the monomeric complex 1. One of the
˚
CtN bond lengths is much shorter (1.015(2) A) whereas
˚
the other one is slightly longer (1.188(3) A) than those in 2
˚
˚
(1.146(6)-1.155(6) A) and 1 (1.148(6)-1.150(6) A). The
Os-CtN angles are almost linear (177.57(14) and
and intertrimer exchange constant J. For a CuIIOsIII
trinuclear compound with SCu = /2 and SOs = /2,
we regard the g tensors as equal. The spin Hamiltonian is
2
1
1
179.60(15)°). The intramolecular Cu Os distances are
3 3 3
˚
5.125 and 5.365 A. The shortest intrachain Os Os and
3 3 3
˚
Cu Cu separations are 6.715 and 10.489 A, respec-
tively, while the shortest interchain Os Os and
3 3 3
H ¼ -2JðSCuSOs1 þ SCuSOs2
Þ
3 3 3
˚
Cu Cu distances are 9.101 and 4.681 A, respectively
(Figure 4c).
3 3 3
(21) (a) Kou, H. -Z.; Zhou, B. C.; Gao, S.; Liao, D.-Z.; Wang, R.-J. Inorg.
Chem. 2003, 42, 5604–5611. (b) Chiari, B.; Cinti, A.; Piovesana, O.; Zanazzi, P. F.
Inorg. Chem. 1995, 34, 2652–2657. (c) Caneschi, A.; Gatteschi, D.; Melandri,
M. C.; Rey, P.; Sessoli, R. Inorg. Chem. 1990, 29, 4228–4234.
(20) Wang, C. F.; Zuo, J. L.; Bartlett, B. M.; Song, Y.; Long, J. R.; You,
X. Z. J. Am. Chem. Soc. 2006, 128, 7162–7163.

1612 Inorganic Chemistry, Vol. 49, No. 4, 2010
Guo et al.
Figure 4. (a) Graphical plot of the final refinement cycle of 3: observed (red line), calculated (green line), and difference X-ray diffraction data (magenta
line) and Bragg peak positions (black ticks)]. (b) Ball and stick diagram of the building unit of 3 with the atom-labeling scheme. (c) View of the 1-D zigzag
chains of 3. All hydrogen atoms and the anion ClO4- are omitted for clarity.
Thus, the molar magnetic susceptibility of the triangular
trimer22 can be expressed as
is written as
Ng2β2
3kT
χt ¼
StðSt þ 1Þ
Ng2β21 þ expð2J=kTÞ þ 10 expð3J=kTÞ
χt ¼
Then, the magnetic susceptibility of the chain is.
4kT 1 þ expð2J=kTÞ þ 2 expð3J=kTÞ
Ng2β21 þ u
χc ¼
StðSt þ 1Þ
Also, the molar magnetic susceptibility of the trimer
3kT 1 -u
Here u=coth(JSt(St þ 1)/kT - kT/JSt(St þ 1).
(22) Kahn, O. Molecular Magnetism; VCH: New York, 1993.

Article
Inorganic Chemistry, Vol. 49, No. 4, 2010 1613
Table 4. Results of the Structural Refinement of
3 using Powder X-ray
Diffraction Data
formula
C27H35ClCuN7O6Os
842.82
formula mass (amu)
cryst syst
space group
monoclinic
C2/c (No. 15)
26.3735(8)
13.4268(4)
18.3958(6)
90
92.237(3)
90
6509.2(3)
1.5406
˚
a (A)
˚
b (A)
˚
c (A)
R (deg)
β (deg)
γ (deg)
3
˚
V (A )
˚
λ (A)
Z
8
1.720
1522
248
280
0.10 (0.01)
0.081, 0.060
0.087, 1.39
Dcalcd (g cm-3
no. of rflns, N
)
Figure 5. Temperature dependence of χMT (circles) and χM-1 (squares)
for 1.
no. of restraints, R
no. of variables, P
max (mean) (shift/esd2)
wRp, Rp
a
RF2, χa
P
P
P
P
2 1/2
]
a RP
and RF2
=
=
|yi,o - yi,c|/ |yi,o|, wRP = [ wi(yi,o - yi,c)2/ wiyi,o
,
P
P
|F2k,o- F2k,c|/ F2k,o, where yi and F2k are the (observed
and calculated) profile intensities and squared structure factors, respec-
tively, wi is a statistical weighting factor, taken as 1/yi,o, and i runs over
all data points and k over the space group permitted reflections, and
P
χ = [ wi(yi,o- yi,c)2/(N - P)]1/2, where P is the number of refined
variables and N the number of extracted and integrated reflections.
a
˚
Table 5. Selected Bond Lengths (A) and Angles (deg) for 3
Cu1-N4
Cu1-N7
Cu1-N6
Cu1-N5
Cu1-N3
N4-C18
N3-C17
2.083(2)
2.050(3)
2.191(2)
2.043(2)
2.132(2)
1.015(2)
1.188(3)
Os1-C18
Os1-O2
Os1-O1
Os1-N2
Os1-N1
Os1-C17
2.028(2)
2.001(2)
2.007(3)
1.984(3)
2.000(2)
2.045(2)
Figure 6. Temperature dependence of χMT (squares) and χM-1 (circles)
for 2. The inset shows the field dependence of the magnetization (squares)
and the Brillouin function curve (line).
N4-Cu1-N7
N4-Cu1-N5
N5-Cu1-N7
N4-Cu1-N3
O1-Os1-N2
O1-Os1-N1
O1-Os1-C17
N1-Os1-N2
N2-Os1-C17
N1-Os1-C17
N4-C18-Os1
Os1-C17-N3
90.43(5)
170.64(6)
85.13(5)
79.08(5)
175.41(7)
93.86(6)
94.41(7)
82.20(5)
83.76(6)
96.61(6)
177.57(14)
179.60(15)
O2-Os1-C18
O1-Os1-C18
N2-Os1-C18
N1-Os1-C18
C17-Os1-C18
O1-Os1-O2
O2-Os1-N2
O2-Os1-N1
O2-Os1-C17
Cu1-N4-C18
Cu1-N3(i)-C17(i)
97.34(7)
86.40(7)
95.48(6)
84.09(6)
178.88(7)
89.70(6)
94.20(6)
176.25(6)
81.91(6)
178.62(14)
179.63(14)
a Symmetry codes: (i) 1.5 - x, -0.5 þ y, -0.5 - z.
On the basis of the molecular field theory, the molar
susceptibility of compound 2 can be modified to include
the interchain coupling as
Figure 7. Temperature dependence of χMT (squares) and χM-1 (circles)
for 3. The inset shows the field dependence of the magnetization (squares)
and the Brillouin function curve (line).
χc
χM
¼
1 -ð2zJ0=Ng2β2Þχc
which results in the sharp decrease of χMT value below
5 K. The ZFC-FC plot (Figure S2, Supporting Infor-
mation) indicates that no long-range ordering occurs
above 2 K.
Compound 3. The magnetic properties of 3 were mea-
sured under an external field of 3 kOe in the range of
2-300 K (Figure 7). The χMT value at room temperature
is 0.786 cm3 mol-1 K, which is close to the spin-only value
of 0.75 cm3 mol-1 K for one CuII (S=1/2) and one OsIII
(S=1/2). When the temperature is lowered, the χMT value
increases smoothly and attains a maximum value of
2.93 cm3 mol-1 K at 2 K. Fitting the data above 50 K
where J0 is the interchain exchange coupling constant
and z is the number of the nearest neighbor chains. The
best fitting in the temperature range of 3-300 K gives
J = þ1.56 cm-1, zJ0 = -0.76 cm-1 and g = 2.19 with
P
R = 2.59 ꢀ 10-4 (R = [(χMT)obsd - (χMT)calcd]2/
P
(χMT)obsd2). The positive value of exchange coupling
through the cyanide bridges suggests ferromagnetic inter-
action between CuII and OsIII centers, and the relatively
large negative value of zJ0 indicates antiferromagnetic
interaction between the neighboring CuIIOsIII chains,

1614 Inorganic Chemistry, Vol. 49, No. 4, 2010
Guo et al.
with the Curie-Weiss law (χM=C/(T - Θ)] gives C=0.76
cm3 mol-1 K and Θ=þ8.77 K. The positive Θ value indi-
cates a ferromagnetic interaction between OsIII and CuII
through the cyanide bridge, which is expected from the
orthogonality of the magnetic orbitals of the metal ions.
The magnetization of this compound per [CuOs] unit
reaches a value of 1.81 Nβ mol-1 at 2.0 K and 50 kOe
(Figure 7 inset), nearly consistent with the expected
saturation value of 2.0 Nβ for the sum of one OsIII and
one CuII magnetic moment. The experimental M - H
curve of 3 is above the Brillouin function curve below
40 kOe, which suggests ferromagnetic coupling between
OsIII and CuII ions. Using an approximate approach
similar to that for compound 2, the 1-D chain of 3 can
be treated as the repeating unit of CuOs dimers with the
same intradimer and interdimer exchange constant J; the
magnetic susceptibilities can be expressed by the follow-
ing equation22 derived from the isotropic exchange spin
Hamiltonian H=-2JSASB:
indicate a ferromagnetic interaction between CuII and
OsIII centers. The ZFC-FC plot (Figure S3, Supporting
Information) indicates that no long-range ordering oc-
curs above 2 K.
Concluding Remarks
Two 1-D zigzag CuIIOsIII chains based on a new para-
magnetic osmium(III) building block, trans-[Os(salen)-
(CN)2]-, have been synthesized and structurally character-
ized. They all exhibit intrachain ferromagnetic coupling
between CuII and OsIII through cyanide ligands. The present
work shows that [Os(salen)(CN)2]- is a good building
block for the construction of low-dimensional 3d-5d
magnetic materials. The exchange interaction between
OsIII and CuII in these two compounds is weak, which may
be partially due to the Cu(II) ions having only S=1/2. It is
expected that the magnetic coupling would be stronger if the
CuII ions were replaced by metal ions with larger spins (e.g.,
high-spin MnIII or FeIII), owing to greater radial extension of
the d orbitals and higher degree of electron density delo-
calization over the bridging cyanides. The synthesis of various
MnIIIOsIII polymersbasedon[Os(salen)(CN)2]- is in progress.
2Ng2β2
1
Ng2β2
3kT
χd
¼
¼
SdðSd þ 1Þ
kT 3 þ expð -2J=kTÞ
Ng2β21 þ u
Acknowledgment. The work described in this paper was
supported by grants from the National Natural Science
Foundation of China (NSFC 20831160505), the National
Basic Research Program of China (2009CB929403), the
Research Grants Council of Hong Kong Joint Research
Scheme (N_CityU 107/08), and the City University of
Hong Kong (SRG 7002319).
χc ¼
SdðSd þ 1Þ
3kT 1 -u
Here u=coth(JSd (Sd þ 1)/kT - kT/JSd (Sd þ 1).
χc
χM
¼
1 -ð2zJ0=Ng2β2Þχc
The susceptibilities from 2 to 300 K were simulated,
giving the best fit with the parameters J=þ2.03 cm-1, zJ0
=-0.18 cm-1, and g=2.11 with R=1.49 ꢀ 10-3 (R=
Supporting Information Available: CIF files giving crystal-
lographic data for 1-3 (CCDC No. 744749) and figures giving
ESI/MS spectra. This material is available free of charge via the
Internet at http://pubs.acs.org.
P
P
[(χMT)obsd - (χMT)calcd]2/ (χMT)obsd2). These results