Crystal structure of di-chlorido-{2-[(2-hy-droxyeth-yl)(pyridin-2-ylmeth-yl)amino]-ethano-lato-κ(4) N,N',O,O'}iron(III) dihydrate from synchrotron data.

In the title compound, [Fe(C10H15N2O2)Cl2]·2H2O, the Fe(III) ion is coordinated by two N and two O atoms of the tetra-dentate 2-{(2-hy-droxy-eth-yl)(pyridin-2-ylmeth-yl)amino}-ethano-late ligand and by two chloride anions, resulting in a distorted octa-hedral coordination sphere. The average Fe-X (X = ligand N and O atoms) and Fe-Cl bond lengths are 2.10 and 2.32 Å, respectively. In the crystal, duplex O-H⋯O hydrogen bonds between the hydroxyl and eth-oxy groups of two neighbouring complexes give rise to a dimeric unit. The dimers are connected to the lattice water mol-ecules (one of which is equally disordered over two sets of sites) through O-H⋯Cl hydrogen bonds, forming undulating sheets parallel to (010). Weak C-H⋯Cl hydrogen bonds are also observed.

Chemical context

Tetra­dentate ligands including n class="Chemical">pyridine and hydroxyl groups have attracted considerable attention in chemistry and mat­erials science (Paz et al., 2012 ▶; Li et al., 2007 ▶). These ligands are able to form multinuclear complexes with various transition metal ions, leading to dimeric, trimeric, tetra­meric or polymeric structures through the deprotonation of hydroxyl groups (Shin et al., 2010 ▶; Han et al., 2009 ▶). Such multinuclear complexes have potential applications in catalysis and magnetic materials. For example, FeIII and CoII/III complexes with amino­ethanol moieties have been studied as oxidation catalysts of various olefins and investigated due to their magnetic properties (Shin et al., 2011 ▶, 2014 ▶). Moreover, MnII/III complexes containing hydroxyl substituents exhibit excellent single-mol­ecular magnetic properties due to magnetic spin-orbit anisotropy (Wu et al., 2010 ▶).

Here, we report the synthesis and crystal structure of a complex with six-coordinate FeIII constructed from the n class="Species">tetra­dentate ligand 2-[(2-hy­droxy­eth­yl)(pyridin-2-ylmeth­yl)amino]­ethanol (H2pmide; C10H17N2O2) and chloride anions, [Fe(Hpmide)Cl2]·2H2O, (I).

Structural commentary

A view of the mol­ecular structure of compound (I) is shown in Fig. 1 ▶. The coordination sphere of the FeIII ion can be described as distorted octa­hedral, consisting of the two n class="Chemical">N atoms and two O atoms from the Hpmide ligand, and two chloride anions. The chloride anions are trans to the deprotonated eth­oxy O atom and the N atom of the pyridine group of the Hpmide ligand, respectively, and coordinate in cis position to each other. The average Fe—X Hpmide (X = N, O) bond length is 2.10 Å and the Fe—Cl bond lengths are 2.2773 (5) (equatorial) and 2.3581 (7) (axial) Å. Both the average Fe—N (2.182 Å) and Fe—O (2.010 Å) distances in (I) are comparable to those found in related N2O2-chelated high-spin FeIII complexes (Shin et al., 2014 ▶; Cappillino et al., 2012 ▶). The bite angles of the five-membered chelate rings in (I) range from 76.59 (5) to 81.45 (4)°.

Figure 1

View of the mol­ecular structure of the title compound, showing the atom-labelling scheme, with displacement ellipsoids drawn at the 50% probability level. H atoms and lattice water mol­ecules are omitted for clarity except for the H atom of the hydroxyl group.

Supra­molecular features

The hydroxyl substituent of the n class="Chemical">Hpmide ligand forms a strong hydrogen bond with the O atom of the deprotonated eth­oxy group of a neighbouring mol­ecule. These duplex inter­actions lead to a dinuclear dimeric unit. The dimers are linked through O—H⋯Cl inter­actions to the lattice water mol­ecules, that are likewise connected to each other through O—H⋯O hydrogen bonds. All these hydrogen-bonding inter­actions (Steed & Atwood, 2009 ▶) lead to the formation of undulating sheets parallel to (010). Further weak hydrogen bonding between pyridine and methyl H atoms and chloride anions stabilizes this arrangement (Fig. 2 ▶ and Table 1 ▶).

Figure 2

View of the crystal packing of the title compound, with inter­molecular O—H⋯O hydrogen bonds between FeIII complex mol­ecules drawn as blue dashed lines. C—H⋯Cl hydrogen bonds are indicated as red dashed lines; water mol­ecules and chloride anions are also connected through O—H⋯O hydrogen bonds (black dashed lines).

Table 1

Hydrogen-bond geometry (, )

DHA	DH	HA	D A	DHA
O1W1H1W1Cl1	0.84(1)	2.51(3)	3.279(4)	152(5)
O1W2H2W2Cl1	0.84(1)	2.91(5)	3.470(4)	125(5)
O2H1O2O1i	0.83(2)	1.69(2)	2.5196(14)	177(2)
O1W1H2W1O2W ii	0.84(1)	2.15(4)	2.876(7)	144(7)
O1W2H1W2O2W ii	0.84(1)	2.06(5)	2.647(8)	126(5)
O1W2H1W2O2W iii	0.84(1)	2.06(3)	2.836(8)	153(6)
C4H4Cl1iv	0.95	2.76	3.5962(16)	147
C9H9ACl1v	0.99	2.78	3.6371(15)	145
C3H3Cl2vi	0.95	2.80	3.5721(16)	139

Symmetry codes: (i) ; (ii) ; (iii) ; (iv) ; (v) ; (vi) .

Database survey

A search of the Cambridge Structural Database (Version 5.35, November 2013 with three updates; Groom & Allen, 2014 ▶) indicated that five complexes derived from the n class="Chemical">H2pmide ligand have been reported. These include NiII and MnII/III; FeIII complexes have been studied for their magnetic properties and catalytic effects (Saalfrank et al., 2001 ▶; Wu et al., 2010 ▶; Shin et al., 2014 ▶).

Synthesis and crystallization

The H2pmide ligand was prepared following a previously reported mn class="Chemical">ethod (Wu et al., 2010 ▶). Compound (I) was prepared as follows: to a MeOH solution (4 ml) of FeCl2·4H2O (81 mg, 0.408 mmol) was added dropwise a MeOH solution (3 ml) of H2pmide (80 mg, 0.408 mmol). The colour became yellow, and then the solution was stirred for 30 min at room temperature. Yellow crystals of (I) were obtained by diffusion of diethyl ether into the yellow solution for several days, and were collected by filtration and washed with diethyl ether and dried in air. Yield: 67 mg (46%). Elemental analysis calculated for C10H15Cl2FeN2O2: C 37.30, H 4.70, N 8.70%; found: C 37.19, H 4.58, N 8.78%.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2 ▶. H atoms attached to C atoms were placed in geometrically idealized positions and constrained to ride on their parent atoms, with C—H distances of 0.95 (n class="Disease">aromatic H atoms) and 0.99 Å (open-chain H atoms) and with U iso(H) values of 1.2U eq(C) of the parent atoms. One lattice water mol­ecule (OW1) was found to be equally disordered over two positions. The H atoms of this disordered water mol­ecule (H1W1 and H1W2) were located from difference Fourier maps and refined with restraints and a fixed O—H distances of 0.84 Å, with U iso(H) values of 1.2U eq(O). Moreover, the second water mol­ecule (O2W) was modelled without hydrogen atoms because difference Fourier maps did not suggest suitable H atoms.

Table 2

Experimental details

Crystal data
Chemical formula	[Fe(C10H15N2O2)Cl2]2H2O
M r	358.02
Crystal system, space group	Monoclinic, P21/c
Temperature (K)	100
a, b, c ()	7.2690(15), 14.497(3), 14.094(3)
()	95.86(3)
V (3)	1477.4(5)
Z	4
Radiation type	Synchrotron, = 0.62998
(mm1)	0.99
Crystal size (mm)	0.10 0.10 0.08
Data collection
Diffractometer	ADSC Q210 CCD area-detector
Absorption correction	Empirical (using intensity measurements) (HKL3000sm SCALEPACK; Otwinowski Minor, 1997 ▶)
T min, T max	0.907, 0.925
No. of measured, independent and observed [I > 2(I)] reflections	14975, 4056, 3866
R int	0.021
(sin /)max (1)	0.696
Refinement
R[F 2 > 2(F 2)], wR(F 2), S	0.027, 0.073, 1.04
No. of reflections	4056
No. of parameters	197
No. of restraints	7
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
max, min (e 3)	1.51, 0.84

Computer programs: PAL ADSC Quantum-210 ADX (Arvai Nielsen, 1983 ▶), HKL3000sm (Otwinowski Minor, 1997 ▶), SHELXS2013/1 and SHELXL2014/7 (Sheldrick, 2008 ▶), ORTEP-3 for Windows and WinGX (Farrugia, 2012 ▶).

Crystal structure: contains datablock(s) I. DOI: 10.1107/S1600536814022089/wm5071sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536814022089/wm5071Isup2.hkl

CCDC reference: 1027864

Additional supporting information: crystallographic information; 3D view; checkCIF report

[Fe(C10H15N2O2)Cl2]·2H2O	F(000) = 740
Mr = 358.02	Dx = 1.610 Mg m−3
Monoclinic, P21/c	Synchrotron radiation, λ = 0.62998 Å
a = 7.2690 (15) Å	Cell parameters from 47717 reflections
b = 14.497 (3) Å	θ = 0.4–33.6°
c = 14.094 (3) Å	µ = 0.99 mm−1
β = 95.86 (3)°	T = 100 K
V = 1477.4 (5) Å3	Block, yellow
Z = 4	0.10 × 0.10 × 0.08 mm

ADSC Q210 CCD area-detector diffractometer	3866 reflections with I > 2σ(I)
Radiation source: PLSII 2D bending magnet	Rint = 0.021
ω scan	θmax = 26.0°, θmin = 2.5°
Absorption correction: empirical (using intensity measurements) (HKL3000sm SCALEPACK; Otwinowski & Minor, 1997)	h = −10→10
Tmin = 0.907, Tmax = 0.925	k = −19→19
14975 measured reflections	l = −19→19
4056 independent reflections

Refinement on F2	7 restraints
Least-squares matrix: full	Hydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.027	H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.073	w = 1/[σ2(Fo2) + (0.0354P)2 + 1.6679P] where P = (Fo2 + 2Fc2)/3
S = 1.04	(Δ/σ)max = 0.001
4056 reflections	Δρmax = 1.51 e Å−3
197 parameters	Δρmin = −0.84 e Å−3

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.

	x	y	z	Uiso*/Ueq	Occ. (<1)
Fe1	0.49921 (2)	0.59458 (2)	0.35450 (2)	0.00581 (6)
Cl1	0.66209 (5)	0.61966 (2)	0.22045 (2)	0.01181 (8)
Cl2	0.32215 (5)	0.47400 (2)	0.29547 (2)	0.01270 (8)
O1	0.70234 (13)	0.53542 (7)	0.42787 (7)	0.00933 (18)
O2	0.33434 (14)	0.60360 (7)	0.46844 (7)	0.00925 (18)
H1O2	0.322 (3)	0.5590 (12)	0.5041 (13)	0.011*
N1	0.32550 (15)	0.70945 (8)	0.30279 (8)	0.0085 (2)
N2	0.62789 (15)	0.71338 (8)	0.43157 (8)	0.0075 (2)
C1	0.15712 (19)	0.70132 (10)	0.25359 (10)	0.0117 (2)
H1	0.1099	0.6415	0.2383	0.014*
C2	0.05082 (19)	0.77769 (11)	0.22469 (10)	0.0143 (3)
H2	−0.0669	0.7703	0.1896	0.017*
C3	0.1193 (2)	0.86521 (11)	0.24795 (11)	0.0156 (3)
H3	0.0492	0.9185	0.2288	0.019*
C4	0.2913 (2)	0.87365 (10)	0.29950 (11)	0.0130 (3)
H4	0.3401	0.9328	0.3169	0.016*
C5	0.39138 (18)	0.79407 (9)	0.32537 (10)	0.0089 (2)
C6	0.58321 (19)	0.79876 (9)	0.37700 (10)	0.0107 (2)
H6A	0.6743	0.8079	0.3302	0.013*
H6B	0.5917	0.8522	0.4210	0.013*
C7	0.82796 (18)	0.69147 (9)	0.43890 (10)	0.0102 (2)
H7A	0.8958	0.7310	0.4879	0.012*
H7B	0.8770	0.7035	0.3771	0.012*
C8	0.85570 (19)	0.58946 (9)	0.46615 (11)	0.0125 (3)
H8A	0.9699	0.5663	0.4416	0.015*
H8B	0.8706	0.5835	0.5365	0.015*
C9	0.56136 (19)	0.71512 (10)	0.52794 (10)	0.0113 (2)
H9A	0.5759	0.7781	0.5548	0.014*
H9B	0.6373	0.6726	0.5708	0.014*
C10	0.35997 (19)	0.68663 (10)	0.52331 (10)	0.0117 (2)
H10A	0.3250	0.6762	0.5885	0.014*
H10B	0.2804	0.7362	0.4932	0.014*
O1W1	0.4145 (8)	0.5368 (3)	0.0321 (3)	0.0527 (11)	0.5
H1W1	0.444 (8)	0.551 (5)	0.0896 (16)	0.063*	0.5
H2W1	0.300 (3)	0.526 (6)	0.025 (4)	0.063*	0.5
O1W2	0.3007 (7)	0.5629 (4)	0.0504 (3)	0.0549 (11)	0.5
H1W2	0.190 (3)	0.546 (5)	0.041 (4)	0.066*	0.5
H2W2	0.314 (8)	0.593 (4)	0.101 (3)	0.066*	0.5
O2W	0.0911 (9)	0.4335 (4)	0.9619 (4)	0.182 (2)

	U11	U22	U33	U12	U13	U23
Fe1	0.00713 (10)	0.00133 (10)	0.00853 (10)	−0.00039 (6)	−0.00140 (6)	0.00067 (6)
Cl1	0.01740 (15)	0.00679 (15)	0.01158 (14)	−0.00204 (11)	0.00321 (11)	0.00141 (10)
Cl2	0.01370 (15)	0.00686 (15)	0.01705 (15)	−0.00509 (10)	−0.00075 (11)	−0.00279 (11)
O1	0.0089 (4)	0.0039 (4)	0.0146 (4)	−0.0005 (3)	−0.0017 (3)	0.0029 (3)
O2	0.0115 (4)	0.0047 (4)	0.0117 (4)	−0.0016 (3)	0.0018 (3)	0.0014 (3)
N1	0.0085 (5)	0.0051 (5)	0.0115 (5)	0.0001 (4)	−0.0005 (4)	0.0023 (4)
N2	0.0082 (5)	0.0031 (5)	0.0105 (5)	−0.0002 (4)	−0.0016 (4)	0.0019 (4)
C1	0.0100 (6)	0.0114 (6)	0.0132 (6)	−0.0008 (5)	−0.0009 (5)	0.0036 (5)
C2	0.0083 (5)	0.0179 (7)	0.0165 (6)	0.0022 (5)	−0.0004 (5)	0.0072 (5)
C3	0.0129 (6)	0.0134 (7)	0.0206 (7)	0.0072 (5)	0.0025 (5)	0.0074 (5)
C4	0.0144 (6)	0.0056 (6)	0.0191 (6)	0.0035 (5)	0.0025 (5)	0.0040 (5)
C5	0.0102 (5)	0.0045 (6)	0.0121 (6)	0.0012 (4)	0.0010 (4)	0.0023 (4)
C6	0.0120 (6)	0.0019 (5)	0.0172 (6)	−0.0010 (4)	−0.0033 (5)	0.0028 (4)
C7	0.0072 (5)	0.0068 (6)	0.0161 (6)	−0.0016 (4)	−0.0022 (4)	0.0025 (4)
C8	0.0079 (5)	0.0077 (6)	0.0207 (7)	−0.0005 (4)	−0.0041 (5)	0.0046 (5)
C9	0.0156 (6)	0.0083 (6)	0.0099 (6)	−0.0024 (5)	0.0001 (5)	−0.0024 (4)
C10	0.0147 (6)	0.0070 (6)	0.0140 (6)	0.0008 (5)	0.0041 (5)	−0.0012 (5)
O1W1	0.095 (4)	0.035 (2)	0.0249 (16)	−0.019 (2)	−0.0105 (19)	0.0025 (14)
O1W2	0.066 (3)	0.069 (3)	0.0270 (18)	−0.008 (2)	−0.0078 (18)	−0.0038 (18)
O2W	0.229 (6)	0.182 (5)	0.138 (4)	−0.037 (5)	0.023 (4)	0.009 (4)

Fe1—O1	1.9165 (11)	C4—C5	1.3925 (18)
Fe1—O2	2.1036 (12)	C4—H4	0.9500
Fe1—N1	2.1704 (12)	C5—C6	1.5071 (19)
Fe1—N2	2.1939 (12)	C6—H6A	0.9900
Fe1—Cl2	2.2773 (5)	C6—H6B	0.9900
Fe1—Cl1	2.3581 (7)	C7—C8	1.5360 (19)
O1—C8	1.4229 (16)	C7—H7A	0.9900
O2—C10	1.4326 (17)	C7—H7B	0.9900
O2—H1O2	0.829 (15)	C8—H8A	0.9900
N1—C5	1.3433 (17)	C8—H8B	0.9900
N1—C1	1.3488 (17)	C9—C10	1.516 (2)
N2—C6	1.4759 (17)	C9—H9A	0.9900
N2—C7	1.4818 (17)	C9—H9B	0.9900
N2—C9	1.4878 (18)	C10—H10A	0.9900
C1—C2	1.387 (2)	C10—H10B	0.9900
C1—H1	0.9500	O1W1—H1W1	0.842 (10)
C2—C3	1.390 (2)	O1W1—H2W1	0.842 (10)
C2—H2	0.9500	O1W2—H1W2	0.842 (10)
C3—C4	1.386 (2)	O1W2—H2W2	0.839 (10)
C3—H3	0.9500
O1—Fe1—O2	94.79 (4)	C3—C4—H4	120.6
O1—Fe1—N1	156.10 (4)	C5—C4—H4	120.6
O2—Fe1—N1	81.45 (4)	N1—C5—C4	122.05 (13)
O1—Fe1—N2	79.52 (5)	N1—C5—C6	116.46 (11)
O2—Fe1—N2	79.66 (4)	C4—C5—C6	121.45 (12)
N1—Fe1—N2	76.59 (5)	N2—C6—C5	110.93 (10)
O1—Fe1—Cl2	103.25 (4)	N2—C6—H6A	109.5
O2—Fe1—Cl2	88.96 (3)	C5—C6—H6A	109.5
N1—Fe1—Cl2	100.28 (4)	N2—C6—H6B	109.5
N2—Fe1—Cl2	168.51 (3)	C5—C6—H6B	109.5
O1—Fe1—Cl1	94.54 (4)	H6A—C6—H6B	108.0
O2—Fe1—Cl1	166.87 (3)	N2—C7—C8	109.06 (11)
N1—Fe1—Cl1	86.28 (3)	N2—C7—H7A	109.9
N2—Fe1—Cl1	92.98 (3)	C8—C7—H7A	109.9
Cl2—Fe1—Cl1	97.869 (19)	N2—C7—H7B	109.9
C8—O1—Fe1	119.26 (8)	C8—C7—H7B	109.9
C10—O2—Fe1	114.30 (8)	H7A—C7—H7B	108.3
C10—O2—H1O2	110.1 (14)	O1—C8—C7	110.95 (11)
Fe1—O2—H1O2	121.2 (14)	O1—C8—H8A	109.4
C5—N1—C1	118.97 (12)	C7—C8—H8A	109.4
C5—N1—Fe1	116.11 (9)	O1—C8—H8B	109.4
C1—N1—Fe1	124.88 (9)	C7—C8—H8B	109.4
C6—N2—C7	112.22 (11)	H8A—C8—H8B	108.0
C6—N2—C9	112.75 (11)	N2—C9—C10	111.01 (11)
C7—N2—C9	110.38 (11)	N2—C9—H9A	109.4
C6—N2—Fe1	109.90 (8)	C10—C9—H9A	109.4
C7—N2—Fe1	103.42 (8)	N2—C9—H9B	109.4
C9—N2—Fe1	107.66 (8)	C10—C9—H9B	109.4
N1—C1—C2	122.02 (13)	H9A—C9—H9B	108.0
N1—C1—H1	119.0	O2—C10—C9	108.90 (11)
C2—C1—H1	119.0	O2—C10—H10A	109.9
C1—C2—C3	118.93 (13)	C9—C10—H10A	109.9
C1—C2—H2	120.5	O2—C10—H10B	109.9
C3—C2—H2	120.5	C9—C10—H10B	109.9
C4—C3—C2	119.12 (13)	H10A—C10—H10B	108.3
C4—C3—H3	120.4	H1W1—O1W1—H2W1	108 (3)
C2—C3—H3	120.4	H1W2—O1W2—H2W2	109 (3)
C3—C4—C5	118.90 (14)
C5—N1—C1—C2	0.7 (2)	Fe1—N2—C6—C5	34.62 (13)
Fe1—N1—C1—C2	178.26 (10)	N1—C5—C6—N2	−26.63 (17)
N1—C1—C2—C3	−0.6 (2)	C4—C5—C6—N2	155.71 (13)
C1—C2—C3—C4	−0.2 (2)	C6—N2—C7—C8	−161.67 (11)
C2—C3—C4—C5	0.8 (2)	C9—N2—C7—C8	71.64 (14)
C1—N1—C5—C4	−0.1 (2)	Fe1—N2—C7—C8	−43.28 (12)
Fe1—N1—C5—C4	−177.80 (10)	Fe1—O1—C8—C7	−0.47 (15)
C1—N1—C5—C6	−177.70 (12)	N2—C7—C8—O1	31.76 (16)
Fe1—N1—C5—C6	4.56 (16)	C6—N2—C9—C10	83.81 (14)
C3—C4—C5—N1	−0.7 (2)	C7—N2—C9—C10	−149.79 (11)
C3—C4—C5—C6	176.80 (13)	Fe1—N2—C9—C10	−37.58 (12)
C7—N2—C6—C5	149.11 (12)	Fe1—O2—C10—C9	−35.00 (13)
C9—N2—C6—C5	−85.49 (14)	N2—C9—C10—O2	48.37 (15)

D—H···A	D—H	H···A	D···A	D—H···A
O1W1—H1W1···Cl1	0.84 (1)	2.51 (3)	3.279 (4)	152 (5)
O1W2—H2W2···Cl1	0.84 (1)	2.91 (5)	3.470 (4)	125 (5)
O2—H1O2···O1i	0.83 (2)	1.69 (2)	2.5196 (14)	177 (2)
O1W1—H2W1···O2Wii	0.84 (1)	2.15 (4)	2.876 (7)	144 (7)
O1W2—H1W2···O2Wii	0.84 (1)	2.06 (5)	2.647 (8)	126 (5)
O1W2—H1W2···O2Wiii	0.84 (1)	2.06 (3)	2.836 (8)	153 (6)
C4—H4···Cl1iv	0.95	2.76	3.5962 (16)	147
C9—H9A···Cl1v	0.99	2.78	3.6371 (15)	145
C3—H3···Cl2vi	0.95	2.80	3.5721 (16)	139