A novel one-dimensional complex: catena-poly­[[manganese(III)-di-μ-2-[(2-hydroxy­ethyl)­imino­methyl]­phenolato-κ²O¹,N:κO²;κO²:κ²O¹] chloride]

In the title one-dimensional complex, {[Mn^III(C₉H₁₀NO₂)₂]Cl}_n, the Schiff base ligand 2-[(2-hydroxy­ethyl)­imino­methyl]­phenolate (Hsae⁻) functions as both a bridging and a chelating ligand. The Mn^III ion is six-coordinated by two N and four O atoms from four different Hsae⁻ ligands, yielding a distorted MnO₄N₂ octahedral environment. Each [Mn^III(Hsae)₂]⁺ cationic unit has the Mn atom on an inversion centre and each [Mn^III(Hsae)₂]⁺ cation lies about another inversion centre. The chain-like complex is further extended into a three-dimensional network structure through Cl...H—O hydrogen bonds and C—H...π contacts involving the Hsae⁻ rings.

S1. Comment

Recently, the Schiff base proligand 2-[(2-hydroxyethyl)iminomethyl]phenol (H₂sae) and its derivatives have been employed to assembly discrete alkoxo- or phenoxo-bridged complexes with interesting magnetic properties in the field of coordination chemistry (Oshio et al., 2000, 2003; Koizumi et al., 2003). After deprotonation, H₂sae yields the potentially tridentate Hsae⁻ or sae²⁻ ligands, which possess a ONO donor set and are able to bind in both bridging and chelating modes (Basler et al., 2003). In addition, the favourable flexibility of the –N═ CH₂—CH₂—OH or [–N═CH₂—CH₂—O]⁻ moiety and the appropriate rigidity of the benzene ring structure in Hsae⁻ or sae²⁻ ligands can lead to unexpected complexes with beautiful molecular structures and interesting properties (Koizumi et al., 2005). To date, more than 20 complexes involving Ni^II, Cu^II, Fe^II, Fe^III, Mn^II and Mn^III ions have been reported featuring Hsae⁻ or sae²⁻ ligands and their derivatives (Dey et al., 2002; Nihei et al., 2003; Oshio, Nihei, Yoshida et al., 2005; Boskovic et al., 2003, 2005). It is noteworthy that several of them exhibit the behavior of single-molecule magnets (SMMs) (Oshio, Nihei, Yoshida et al., 2005; Oshio et al., 2004; Oshio, Nihei, Koizumi et al., 2005; Boskovic et al., 2003). However, to the best of our knowledge, all such reported complexes are zero-dimensional, including mono- or binuclear complexes as well as polynuclear clusters. We report here the synthesis and crystal structure of a novel one-dimensional chain-like complex {[Mn^III(Hsae)₂]Cl}_n, (I), which represents a new topology containing Hsae⁻ ligand.

The one-dimensional structure of (I) is depicted in Fig. 1, and selected bond lengths and angles are listed in Table 1. The crystal structure consists of a one-dimensional cationic polymer [Mn^III(Hsae)₂]_nⁿ⁺ and free Cl⁻ anions. Each [Mn^III(Hsae)₂]⁺ cationic unit is centrosymmetric. The Mn atom is six-coordinated symmetrically by two phenoxy O atoms and two N atoms from two Hsae⁻ ligands, and two alkoxy O atoms from the adjacent two [Mn^III(Hsae)₂]⁺ units, yielding a distorted MnO₄N₂ octahedral surrounding. The Mn—O and Mn—N bond lengths are in accordance with the corresponding bonds in bi- or polynuclear complexes involving H₂sae or its derivatives (Table 2). In one Hsae⁻ ligand, the phenoxo O atom and the N atom coordinate to the same Mn atom, whereas the alkoxo O atom coordinates to the next adjacent Mn atom. Alternatively, the complex can be simply considered as doubly linked by two O—C—C═N bridging groups (Fig. 1), which makes the one-dimensional structure look like an infinite `8'-shaped chain. The `8'-shaped chains are linked by Cl⁻ ions through O2—H200···Cl1(x + 1/2, y + 1/2, −z + 1/2) hydrogen bonds to form a two-dimensional network structure. Then the networks are further connected by C—H···π contacts between the Hsae⁻ rings with a shortest CH/C distance [C3—H3···C4(−x + 1/2, y + 1/2, −z + 1/2); Umezawa et al., 1998] of 2.726 Å to yield a three-dimensional non-covalent network structure.

Comparing with the reported alkoxo- or phenoxo-bridged polynuclear complexes containing the Hsae⁻ or sae²⁻ ligand, we found that the key factor favoring the formation of a one-dimensional structure in the title complex, instead of a polynuclear structure, is that the phenoxo or alkoxo O atom does not act as a bridging atom, while the whole Hsae⁻ ligand functions as a bridging group. The synthesis of the title complex is similar to that of the tetranuclear [Mn₄(Hsae)₄Cl₄] complex (Boskovic et al., 2003), except that a different solvent is used; this fact demonstrates that the molecular structures of complexes are strongly dependent on the solvent employed for this system.

S2. Experimental

MnCl₂·4H₂O (0.61 g, 3.09 mmol) was added to a solution of H₂sae (0.51 g, 3.09 mmol) in EtOH (40 ml), and the resulting mixture was stirred overnight and filtered. The filtrate was evaperated to dryness and then dissolved in a mixed solvent of MeOH/MeCN (volume ratio about 1:4). The resulted solution was evaporated at room temperature until dark-brown needles formed.

S3. Refinement

The coordinates of the H atoms of the alkoxo-group were found from difference Fourier maps and normalized to an O—H distance of 0.85 Å. H atoms bound to C atoms were also visible in difference maps and were positioned using the HFIX commands in SHELXL97 (Sheldrick, 1997) and refined as riding atoms (0.97 Å or 0.93 Å).

Computing details

Data collection: CrystalStructure (Rigaku/MSC & Rigaku Corporation, 2004); cell refinement: CrystalStructure; data reduction: CrystalStructure; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP (Sheldrick, 1998); software used to prepare material for publication: XP.

Figures

	Fig. 1. A fragment of the one-dimensional structure of (I), showing the atom-labeling scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms bonded to C atoms have been omitted. [symmetry codes: Mn (A) x, y − 1, z; (B) x, y + 1, z; (C) x, y − 2, z. N,O (A) x, y − 1, z; (B) −x, −y + 1, −z; (AA) −x, −y + 2, −z.]
	Fig. 2. The two-dimensional network of (I), formed by hydrogen-bond interactions (along the c axis). Hydrogen bonds are shown as dashed lines and H atoms have been omitted for clarity.

catena-poly[[manganese(III)-di-µ-2-[(2-hydroxyethyl)iminomethyl]phenolato- κ²O¹,N:κO²;κO²:κ²O¹] chloride]

Crystal data

[Mn(C9H10NO2)2]Cl	F(000) = 864
Mr = 418.76	Dx = 1.547 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71070 Å
Hall symbol: -C 2yc	Cell parameters from 2054 reflections
a = 18.202 (8) Å	θ = 3.8–27.5°
b = 5.700 (2) Å	µ = 0.91 mm^−1
c = 18.703 (9) Å	T = 123 K
β = 112.091 (3)°	Needle, brown
V = 1797.9 (13) Å^3	0.30 × 0.10 × 0.03 mm
Z = 4

Data collection

Rigaku R-AXIS RAPID IP diffractometer	2054 independent reflections
Radiation source: fine-focus sealed tube	1571 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.092
Detector resolution: 100x100 microns pixels mm^-1	θmax = 27.5°, θmin = 3.8°
Oscillation scans	h = −23→23
Absorption correction: multi scan (ABSCOR; Higashi, 1995)	k = −7→6
Tmin = 0.802, Tmax = 0.928	l = −19→24
6807 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.045	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.103	H-atom parameters constrained
S = 0.96	w = 1/[σ^2(Fo^2) + (0.0254P)^2] where P = (Fo^2 + 2Fc^2)/3
2054 reflections	(Δ/σ)max < 0.001
122 parameters	Δρmax = 0.50 e Å^−3
0 restraints	Δρmin = −0.42 e Å^−3

Special details

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Mn1	0.0000	0.5000	0.0000	0.01232 (18)
N1	0.08849 (10)	0.7300 (3)	0.01181 (11)	0.0122 (4)
O1	0.05297 (9)	0.4074 (3)	0.10230 (8)	0.0161 (4)
Cl1	0.2500	1.2500	0.0000	0.0246 (3)
C1	0.13670 (13)	0.8080 (4)	0.07785 (13)	0.0137 (5)
H1	0.1752	0.9144	0.0773	0.016*
C2	0.13578 (13)	0.7442 (4)	0.15201 (13)	0.0139 (5)
C3	0.17832 (12)	0.8837 (4)	0.21678 (13)	0.0159 (5)
H3	0.2051	1.0162	0.2105	0.019*
C4	0.18058 (13)	0.8262 (4)	0.28877 (13)	0.0185 (6)
H4	0.2075	0.9214	0.3309	0.022*
C5	0.14221 (13)	0.6237 (4)	0.29834 (13)	0.0177 (5)
H5	0.1449	0.5821	0.3474	0.021*
C6	0.10030 (14)	0.4843 (4)	0.23607 (14)	0.0166 (6)
H6	0.0753	0.3494	0.2436	0.020*
C7	0.09493 (13)	0.5434 (4)	0.16174 (14)	0.0133 (5)
C8	0.10016 (13)	0.8184 (4)	−0.05735 (12)	0.0134 (5)
H8A	0.0858	0.6970	−0.0966	0.016*
H8B	0.1557	0.8564	−0.0442	0.016*
C9	0.05010 (13)	1.0349 (4)	−0.08921 (14)	0.0149 (5)
H9A	0.0561	1.0823	−0.1366	0.018*
H9B	−0.0053	0.9968	−0.1016	0.018*
O2	0.07193 (10)	1.2272 (2)	−0.03563 (9)	0.0168 (4)
H10	0.1215	1.2535	−0.0190	0.026 (8)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Mn1	0.0136 (3)	0.0080 (3)	0.0147 (4)	−0.00376 (19)	0.0046 (2)	−0.00051 (19)
N1	0.0131 (10)	0.0072 (10)	0.0162 (12)	0.0007 (8)	0.0054 (9)	0.0003 (8)
O1	0.0189 (9)	0.0116 (9)	0.0146 (9)	−0.0066 (7)	0.0026 (7)	−0.0004 (7)
Cl1	0.0147 (5)	0.0313 (5)	0.0226 (6)	0.0093 (4)	0.0009 (4)	−0.0024 (4)
C1	0.0146 (12)	0.0076 (11)	0.0188 (14)	−0.0006 (9)	0.0062 (11)	0.0015 (10)
C2	0.0123 (12)	0.0112 (12)	0.0169 (14)	0.0003 (9)	0.0039 (11)	0.0005 (10)
C3	0.0129 (11)	0.0124 (12)	0.0211 (15)	−0.0031 (10)	0.0049 (11)	−0.0015 (11)
C4	0.0180 (13)	0.0160 (13)	0.0172 (15)	−0.0020 (10)	0.0019 (11)	−0.0048 (11)
C5	0.0202 (13)	0.0188 (13)	0.0153 (14)	0.0017 (11)	0.0079 (11)	0.0002 (11)
C6	0.0184 (13)	0.0143 (13)	0.0183 (15)	−0.0035 (10)	0.0082 (11)	0.0018 (10)
C7	0.0104 (11)	0.0102 (11)	0.0169 (14)	0.0011 (9)	0.0025 (10)	−0.0002 (10)
C8	0.0166 (12)	0.0097 (12)	0.0162 (13)	−0.0054 (9)	0.0088 (10)	−0.0036 (10)
C9	0.0173 (12)	0.0103 (12)	0.0169 (15)	−0.0027 (9)	0.0063 (11)	−0.0008 (10)
O2	0.0145 (9)	0.0087 (8)	0.0267 (10)	−0.0030 (7)	0.0071 (8)	−0.0045 (7)

Geometric parameters (Å, º)

Mn1—O1^i	1.8659 (17)	C4—C5	1.395 (3)
Mn1—O1	1.8659 (17)	C4—H4	0.9300
Mn1—N1	2.0232 (18)	C5—C6	1.379 (3)
Mn1—N1^i	2.0232 (18)	C5—H5	0.9300
Mn1—O2^ii	2.2874 (15)	C6—C7	1.398 (3)
Mn1—O2^iii	2.2874 (15)	C6—H6	0.9300
N1—C1	1.295 (3)	C8—C9	1.517 (3)
N1—C8	1.476 (3)	C8—H8A	0.9700
O1—C7	1.335 (3)	C8—H8B	0.9700
C1—C2	1.440 (3)	C9—O2	1.437 (3)
C1—H1	0.9300	C9—H9A	0.9700
C2—C3	1.412 (3)	C9—H9B	0.9700
C2—C7	1.413 (3)	O2—Mn1^iv	2.2874 (15)
C3—C4	1.371 (3)	O2—H10	0.8500
C3—H3	0.9300
O1^i—Mn1—O1	180.00 (11)	C3—C4—C5	119.5 (2)
O1^i—Mn1—N1	90.68 (7)	C3—C4—H4	120.3
O1—Mn1—N1	89.32 (7)	C5—C4—H4	120.3
O1^i—Mn1—N1^i	89.32 (7)	C6—C5—C4	120.9 (2)
O1—Mn1—N1^i	90.68 (7)	C6—C5—H5	119.6
N1—Mn1—N1^i	180.00 (10)	C4—C5—H5	119.6
O1^i—Mn1—O2^ii	88.56 (7)	C5—C6—C7	120.7 (2)
O1—Mn1—O2^ii	91.44 (7)	C5—C6—H6	119.6
N1—Mn1—O2^ii	92.71 (7)	C7—C6—H6	119.6
N1^i—Mn1—O2^ii	87.29 (7)	O1—C7—C6	119.5 (2)
O1^i—Mn1—O2^iii	91.44 (7)	O1—C7—C2	121.8 (2)
O1—Mn1—O2^iii	88.56 (7)	C6—C7—C2	118.7 (2)
N1—Mn1—O2^iii	87.29 (7)	N1—C8—C9	111.04 (17)
N1^i—Mn1—O2^iii	92.71 (7)	N1—C8—H8A	109.4
O2^ii—Mn1—O2^iii	180.00 (7)	C9—C8—H8A	109.4
C1—N1—C8	116.69 (18)	N1—C8—H8B	109.4
C1—N1—Mn1	123.54 (15)	C9—C8—H8B	109.4
C8—N1—Mn1	119.78 (14)	H8A—C8—H8B	108.0
C7—O1—Mn1	127.09 (15)	O2—C9—C8	112.27 (19)
N1—C1—C2	125.6 (2)	O2—C9—H9A	109.2
N1—C1—H1	117.2	C8—C9—H9A	109.2
C2—C1—H1	117.2	O2—C9—H9B	109.2
C3—C2—C7	119.4 (2)	C8—C9—H9B	109.2
C3—C2—C1	118.9 (2)	H9A—C9—H9B	107.9
C7—C2—C1	121.7 (2)	C9—O2—Mn1^iv	133.10 (13)
C4—C3—C2	120.8 (2)	C9—O2—H10	111.5
C4—C3—H3	119.6	Mn1^iv—O2—H10	114.8
C2—C3—H3	119.6

Symmetry codes: (i) −x, −y+1, −z; (ii) −x, −y+2, −z; (iii) x, y−1, z; (iv) x, y+1, z.