A carboxylato-supported alokoxobridged dimangananese(III) complex: bis(μ-benzoato-O:O′)bis[3-(3-methoxysalicylideneamino) propanolato-O,N,O′:O′]dimanganese(III)

Article abstract of DOI:10.1107/S0108270101005790

The title compound, [Mn₂(C₁₁H₁₃ NO₃)₂(C₇H₅ O₂)₂], is a centrosymmetric dinuclear manganese(III) complex in which the two Mn atoms are bridged by two alkoxo groups and supported by two carboxylate groups, with an Mn···Mn distance of 2.8720 (15) A.

Full text of DOI:10.1107/S0108270101005790

metal-organic compounds
Ê
Ê
Acta Crystallographica Section C
Crystal Structure
2.028 (2) A; MnÐO 1.874 (2) and 1.891 (2) A] (Gohdes &
Armstrong, 1992) and [Mn(salpa)(MeOH)Cl]2 (H2salpa = 3-
Ê
salicylidene-amino-1-propanol) [MnÐN 1.995 (4) A; MnÐO
Communications
Ê
1.853 (3) and 1.926 (3) A] (Larson et al., 1992). Two
ISSN 0108-2701
carboxylate O atoms coordinate to the Mn atom via the
elongated axial direction, with MnÐO1 and MnÐO2 bond
Ê
distances of 2.262 (3) and 2.216 (3) A. These bonds are
considerably longer than those found in the equatorial plane,
A carboxylato-supported alkoxo-
bridged dimanganese(III) complex:
bis(l-benzoato-O:O0)bis[3-(3-meth-
oxysalicylideneamino)propanolato-
O,N,O0:O0]dimanganese(III)
Cungen Zhanga*² and Christoph Janiakb
aDepartment of Chemistry, Shanghai Jiaotong University, Shanghai 200240, People's
Republic of China, and bInstitut fur Anorganische und Analytische Chemie,
È
Universitat Freiburg, Albertstraûe 21, D-79104 Freiburg, Germany
È
Correspondence e-mail: cungen@uni-freiburg.de
which could be due in part both to the Jahn±Teller distortion
and to the different type of ligands and their mode of coor-
dination. The Mn2O2 core is exactly planar by symmetry. The
Received 1 March 2001
Accepted 3 April 2001
Ê
MnÁ Á ÁMn distance of 2.8720 (15) A is similar to the distances
The title compound, [Mn2(C11H13NO3)2(C7H5O2)2], is a
centrosymmetric dinuclear manganese(III) complex in which
the two Mn atoms are bridged by two alkoxo groups and
supported by two carboxylate groups, with an MnÁ Á ÁMn
Ê
found in [Mn(salpa)(acetato)]2 [2.869 (1) A] (Mikuriya et al.,
Ê
1981) and [Mn(salpa)(benzoato)]2 [2.855 (2) A] (Zhang, Zhou
et al., 1999), but somewhat shorter than found in [Mn(salpa)-
Ê
(MeOH)Cl]2 [3.011 (1) A] (Larson et al., 1992) and [Mn(salpa)-
Ê
(H2O)Cl]2 [3.001 (1) A] (Zhang, Sun et al., 1999). This indi-
Ê
distance of 2.8720 (15) A.
cates that the effect of two bridging carboxylate groups
instead of four individual axial monodentate ligands, such as
chloride, water or methanol, on the Mn2O2 core is to lead to a
marked decrease in the manganese±manganese separation.
Consequently, the angle O3ÐMnÐO3i is expanded to
Comment
Dinuclear manganese(III) complexes are of current interest
because they can mimic the active sites of manganese-
containing enzymes (Limburg et al., 1999). Recently, it has
been postulated that photosystem-II has two oxo-bridged
dimanganese dimers connected by two carboxylate groups
(Tommos & Babcock, 1998; Hoganson & Babcock, 1997). In
manganese catalase (Halm & Bender, 1988) and manganese
peroxidase (Wariishi et al., 1988), the dimanganese sites are
also found to be bridged by oxo groups. Because of the lack of
suitable crystals, detailed structural information of some
enzymes is still limited. Therefore, it is important to synthesize
di- or polymeric manganese complexes. In this paper, we
report a dimanganese(III) complex with an MnÁ Á ÁMn distance
Ê
of 2.8720 (15) A.
The title complex, (I), is a discrete dinuclear manganese
compound (Fig. 1). The two Mn atoms are related by a crys-
tallographic inversion centre. The coordination geometry
around each Mn atom is an elongated octahedron. The imino
N, phenolic O and two bridging alkoxo O atoms form the
equatorial plane around the Mn atom. The in-plane distances
Ê
Ê
for MnÐN1 [2.000 (3) A], MnÐO3 [1.896 (2) A], MnÐO4
i
[1.859 (2) A] and MnÐO3 [1.939 (2) A; symmetry code: (i)
Ê
Ê
1
x, y, 1
z] are comparable to those in other MnIII
complexes, e.g. [Mn(salpn)(EtOH)2] [H2salpn = N,N0-bis-
(salicylidene)-1,3-diaminopropane] [MnÐN 2.017 (2) and
Figure 1
ORTEP-3 (Farrugia, 1997) view of compound (I) showing the labelling of
the non-H atoms [symmetry code: (i) 1 x, y, 1 z]. Displacement
ellipsoids are drawn at the 50% probability level and H atoms are shown
as spheres of arbitrary radii.
È
² Current address: Institut fur Anorganische und Analytische Chemie,
Universitat Freiburg, Albertstraûe 21, D-79104 Freiburg, Germany.
È
ꢀ
Acta Cryst. (2001). C57, 719±720
# 2001 International Union of Crystallography
Printed in Great Britain ± all rights reserved 719

metal-organic compounds
83.1 (1)ꢁ. This angle is similar to that found in [Mn(salpa)-
(acetato)]2 [83.66 (7)ꢁ] but larger than that in [Mn(salpa)-
(MeOH)Cl]2 [78.2 (1)ꢁ]. Concerning the intermolecular
packing between the dimers, there are no ꢀ-stacking interac-
tions as might have been expected (Janiak, 2000). Some tilted
CÐHÁ Á Áꢀ interactions exist between the benzoate ring and
the aromatic moiety of the salicylidene ligand (Janiak et al.,
2000). The shortest intermolecular ring-centroidÁ Á Áring-
centroid (Cg) contactsꢁ (with interplanar angle) are
Table 1
Selected geometric parameters (A, ).
ꢁ
Ê
MnÐO4
MnÐO3
MnÐO3i
1.859 (2)
1.896 (2)
1.939 (2)
MnÐN1
MnÐO2i
MnÐO1
2.000 (3)
2.216 (3)
2.262 (3)
O4ÐMnÐO3
O4ÐMnÐO3i
O3ÐMnÐO3i
O4ÐMnÐN1
O3ÐMnÐN1
O3iÐMnÐN1
O4ÐMnÐO2i
O3ÐMnÐO2i
O3iÐMnÐO2i
N1ÐMnÐO2i
O4ÐMnÐO1
174.46 (10)
91.80 (10)
83.00 (10)
92.44 (11)
92.72 (11)
175.63 (11)
95.42 (11)
85.91 (10)
83.16 (10)
97.47 (11)
93.84 (11)
O3ÐMnÐO1
O3iÐMnÐO1
N1ÐMnÐO1
O2iÐMnÐO1
C1ÐO1ÐMn
C1ÐO2ÐMni
C8ÐO3ÐMn
C8ÐO3ÐMni
C13ÐO4ÐMn
C11ÐN1ÐMn
C10ÐN1ÐMn
83.72 (10)
83.85 (10)
94.83 (11)
164.26 (9)
123.7 (2)
124.6 (2)
132.3 (2)
127.7 (2)
130.8 (2)
123.0 (3)
120.0 (2)
ii
iii
ꢁ
Ê
Ê
Cg1Á Á ÁCg2 = 4.71 A (54.7 ) and Cg2Á Á ÁCg1 = 4.59 A (54.7 ),
where Cg1 is the centroid of the C2±C7 phenyl ring and Cg2 is
the centroid of the C12±C17 salicyl ring [symmetry codes: (ii)
1
2
1
2
1
2
x, 12 + y,
z; (iii) 12 + x,
y, 12 + z]. The shortest
intermolecular aromatic CÐHÁ Á ÁCg contacts are C6Ð
H6AÁ Á ÁCg2iv = 2.90 and C16ÐH16AÁ Á ÁCg1v = 3.27 A
Ê
Symmetry code: (i) 1 x; y; 1 z.
[symmetry codes: (iv) 12 + x, 21 y, 12 + z; (v) 21 x, 21 + y, 12 z;
calculated with the program PLATON (Spek, 1998)].
Data collection: SMART (Bruker, 1997); cell re®nement: SMART;
data reduction: SAINT (Bruker, 1997); program(s) used to solve
structure: SHELXTL-Plus (Sheldrick, 1998); program(s) used to
re®ne structure: SHELXTL-Plus; molecular graphics: ORTEP-3
(Farrugia, 1997); software used to prepare material for publication:
SHELXTL-Plus.
Experimental
Compound (I) was synthesized by the reaction of the ligand with
manganese benzoate in a 1:1 molar ratio in ethanol. To an ethanolic
solution (20 ml) of 3-methoxysalicylaldehyde (1.52 g, 10 mmol) was
added 3-amino-1-propanol (0.75 g, 10 mmol) with stirring over a
period of 30 min at 323 K; the solution turned yellow. To this solution
was added manganese benzoate dihydrate (3.0 g, 10 mmol); the
colour turned green rapidly. The resulting solution was then put aside
for several days. Crystals were obtained by slow evaporation of the
solvent at room temperature (yield 3.1 g, 82%). Crystal analysis, IR
(KBr pellet, cm 1): 3050 (w), 3000 (w), 2900 (m), 2850 (w), 1615 (s),
1588 (s), 1545 (s), 1460 (s), 1440 (s), 1375 (s), 1375 (s), 1315 (s),
1250 (s), 1220 (s), 1165 (w), 1080 (s), 1060 (s), 950 (m), 870 (m),
735 (s), 670 (m), 630 (s), 610 (s), 485 (w).
CZ thanks the Alexander von Humboldt Foundation for
the award of a Postdoctoral Fellowship. We appreciate the
continuing support of the Fonds der Chemischen Industrie
and of the graduate college `Unpaired electrons' at Freiburg
University. We thank Wenjian Zhang for helpful discussions.
Supplementary data for this paper are available from the IUCr electronic
archives (Reference: JZ1457). Services for accessing these data are
described at the back of the journal.
Crystal data
3
[Mn2(C11H13NO3)2(C7H5O2)2]
Mr = 766.55
Monoclinic, P21/n
Dx = 1.505 Mg m
Mo Kꢂ radiation
Cell parameters from 2959
re¯ections
References
Ê
a = 13.009 (3) A
ꢃ = 1.8±25.0ꢁ
ꢄ = 0.81 mm
T = 293 (2) K
Ê
b = 9.333 (5) A
Blessing, R. H. (1995). Acta Cryst. A51, 33±38.
1
Ê
c = 15.162 (5) A
Bruker (1997). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin,
USA.
Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.
ꢁ = 113.24 (2)ꢁ
V = 1691.5 (11) A
Z = 2
3
Ê
Plate, brown
0.50 Â 0.20 Â 0.18 mm
Gohdes, J. W. & Armstrong, W. H. (1992). Inorg. Chem. 31, 368±373.
Halm, J. E. & Bender, C. J. (1988). J. Am. Chem. Soc. 110, 7554±7555.
Hoganson, C. W. & Babcock, G. T. (1997). Science, 277, 1953±1956.
Janiak, C. (2000). J. Chem. Soc. Dalton Trans. pp. 3885±3896.
Janiak, C., Temizdemir, S., Dechert, S., Deck, W., Girgsdies, F., Heinze, J.,
Kolm, M. J., Scharmann, T. G. & Zipffel, O. M. (2000). Eur. J. Inorg. Chem.
pp. 1229±1241.
Larson, E., Lah, M. S., Li, X., Bonadies, J. A. & Pecoraro, V. L. (1992). Inorg.
Chem. 31, 373±378.
Limburg, J., Vrettos, J. S., Liable-Sands, L. M., Rheingold, A. L., Crabtree,
R. H. & Brudvig, G. W. (1999). Science, 283, 1524±1527.
Mikuriya, M., Torihara, N., Okawa, H. & Kida, S. (1981). Bull. Chem. Soc. Jpn,
54, 1063±1067.
Sheldrick, G. M. (1998). SHELXTL-Plus. Bruker AXS Inc., Madison,
Wisconsin, USA.
Spek, A. L. (1998). PLATON. Version of November 1998. Utrecht University,
The Netherlands.
Tommos, C. & Babcock, G. T. (1998). Acc. Chem. Res. 31, 18±25.
Wariishi, H., Akileswaran, L. & Gold, M. H. (1988). Biochemistry, 27, 5365±
5370.
Data collection
Siemens SMART CCD diffract-
ometer
! scans
Absorption correction: empirical
(SADABS; Blessing, 1995)
Tmin = 0.737, Tmax = 1.000
6242 measured re¯ections
2959 independent re¯ections
2088 re¯ections with I > 2ꢅ(I)
Rint = 0.039
ꢃ
max = 25.0ꢁ
h = 9 ! 15
k = 11 ! 6
l = 18 ! 14
Re®nement
Re®nement on F2
R(F) = 0.047
w = 1/[ꢅ2(Fo2) + (0.0404P)2
+ 0.9800P]
wR(F2) = 0.116
S = 1.06
where P = (Fo2 + 2Fc2)/3
(Á/ꢅ)max
Áꢆmax = 0.28 e A
=
0.002
3
Ê
2954 re¯ections
226 parameters
H-atom parameters constrained
3
Ê
0.34 e A
Áꢆmin
=
Zhang, C., Sun, J., Kong, X. & Zhao, C. (1999). J. Chem. Crystallogr. 29, 203±
206.
Zhang, C.-G., Zhou, Q.-H., Meng, Q.-H., Xu, D.-J. & Xu, Y.-Z. (1999). Synth.
React. Inorg. Met. Org. Chem. 29, 865±876.
H atoms were treated using appropriate riding models (CÐH =
Ê
0.93 and 0.97 A). Uiso(H) = 1.2Ueq(C), except for the H atoms of the
methyl group (C18) for which Uiso(H) = 1.5Ueq(C).
ꢀ
720 Zhang and Janiak
[Mn2(C11H13NO3)2(C7H5O2)2]
Acta Cryst. (2001). C57, 719±720