supplementary materials


gg2121 scheme

Acta Cryst. (2013). E69, m433-m434    [ doi:10.1107/S1600536813018047 ]

{2-[2,2-Bis(4,4-dimethyl-4,5-dihydro-1,3-oxazol-2-yl-[kappa]N)propyl]pyridine}dichloridoiron(II)

G. Roviello, A. Tuzi, C. Capacchione, S. Milione and C. Ferone

Abstract top

The title compound,[FeCl2(C18H25N3O2)], has a distorted tetrahedral Cl2N2 coordination of the FeII atom as a result of the constraints imposed by the 2-[2,2-bis(4,4-dimethyl-4,5-dihydro-1,3-oxazol-2-yl)propyl]pyridine ligand. The pyridine ring is almost perpendicular to the six-membered chelated ring containing the metal atom [dihedral angle between their mean planes = 88.5 (1)°].

Comment top

Metal complexes containing bis(oxazoline) ligands have been widely investigated in the field of homogeneous and asymmetric catalysis. This type of ligands could stabilize the pseudotetrahedral coordination environment of iron(II) affording to efficient ATRP catalyst. The complex Fe(box-py)Cl2 is analogous to Fe(box)Cl2, described in the literature (Ferro et al., 2007) and has been investigated in order to obtaining an improved understanding of the factors influencing efficient ATRP catalysis in iron-based systems. The title compound Fe(box-py)Cl2 (box-py = 2-[2,2-Bis-(4,4-dimethyl-4,5-dihydro-oxazol-2-yl)-propyl]-pyridine), C18H25Cl2Fe1N3O2, has been used as catalyst in the framework of still not published studies on atom transfer radical polymerization (ATRP) of styrene and methylmethacrylate. The molecular structure of Fe(box-py)Cl2 shows a distorted tetrahedral geometry, due to the constraints imposed by the ligand (N1—Fe1—N3 = 88.85 (7)°; Cl1—Fe1—Cl2 = 113.81 (3)°). The Fe—N and Fe—Cl bond distances are similar to that found for Fe(box)Cl2 and for similar saliclylaldiminato complex (O`Reilly et al., 2003). Finally, the heteroaromatic ring is almost perpendicular to the six-membered chelated ring (angle between their mean planes is equal to 88.5 (1)°) and shows the nitrogen atom pointing towards the coordination environment of the iron.

Related literature top

For the analogous bis(oxazoline)iron(II) complex, see: Ferro et al. (2007). For ATRP active catalyst, see: Matyjaszewski & Xia (2001); Kamigaito et al. (2001); De Roma et al. (2011); Ferro et al. (2009). For similar salicylaldiminato complexes, see: O`Reilly et al. (2003). For structural data on metal complexes, see: Li, Lamberti, Mazzeo et al. (2012); Li, Lamberti, Roviello et al. (2012); Busico et al. (2006); D`Auria et al. (2012). For N-rich aromatic heterocycles, see: Carella et al. (2012), Roviello et al. (2012), Milione & Bertolasi (2011).

Experimental top

Fe(box-py)Cl2 was obtained by the reaction of FeCl2 with the ligand. Details for the synthesis will be reported in forthcoming work. Prismatic yellow crystals of the title complex were obtained by slow evaporation of a methylene chloride solution at room temperature.

Refinement top

All the H atoms were generated stereochemically and refined by the riding model with C–H in the range 0.95 Å–0.99 Å and Uiso(H)=1.2Ueq(C); (1.5 for H atoms of methyl groups).

Computing details top

Data collection: COLLECT (Nonius, 1999); cell refinement: DIRAX/LSQ (Duisenberg et al., 2000); data reduction: EVALCCD (Duisenberg et al., 2003); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012).

Figures top
[Figure 1] Fig. 1. ORTEP view of the title compound. Thermal ellipsoids are drawn at 30% probability level.
{2-[2,2-Bis(4,4-dimethyl-4,5-dihydro-1,3-oxazol-2-yl-κN)propyl]pyridine}dichloridoiron(II) top
Crystal data top
[FeCl2(C18H25N3O2)]F(000) = 920
Mr = 442.16Dx = 1.466 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 186 reflections
a = 10.102 (2) Åθ = 3.3–21.8°
b = 13.925 (3) ŵ = 1.04 mm1
c = 14.764 (2) ÅT = 173 K
β = 105.27 (1)°Prism, yellow
V = 2003.5 (6) Å30.20 × 0.10 × 0.10 mm
Z = 4
Data collection top
Bruker–Nonius KappaCCD
diffractometer
4578 independent reflections
Radiation source: fine-focus sealed tube3033 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.054
Detector resolution: 9 pixels mm-1θmax = 27.5°, θmin = 3.2°
CCD rotation images, thick slices scansh = 1213
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
k = 1717
Tmin = 0.820, Tmax = 0.903l = 1719
16483 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.041Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.083H-atom parameters constrained
S = 1.01 w = 1/[σ2(Fo2) + (0.0268P)2 + 1.0658P]
where P = (Fo2 + 2Fc2)/3
4578 reflections(Δ/σ)max = 0.001
240 parametersΔρmax = 0.34 e Å3
0 restraintsΔρmin = 0.30 e Å3
Crystal data top
[FeCl2(C18H25N3O2)]V = 2003.5 (6) Å3
Mr = 442.16Z = 4
Monoclinic, P21/cMo Kα radiation
a = 10.102 (2) ŵ = 1.04 mm1
b = 13.925 (3) ÅT = 173 K
c = 14.764 (2) Å0.20 × 0.10 × 0.10 mm
β = 105.27 (1)°
Data collection top
Bruker–Nonius KappaCCD
diffractometer
4578 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
3033 reflections with I > 2σ(I)
Tmin = 0.820, Tmax = 0.903Rint = 0.054
16483 measured reflectionsθmax = 27.5°
Refinement top
R[F2 > 2σ(F2)] = 0.041H-atom parameters constrained
wR(F2) = 0.083Δρmax = 0.34 e Å3
S = 1.01Δρmin = 0.30 e Å3
4578 reflectionsAbsolute structure: ?
240 parametersAbsolute structure parameter: ?
0 restraintsRogers parameter: ?
Special details top

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 (Å2) top
xyzUiso*/Ueq
Fe10.89069 (4)0.34069 (2)0.30170 (2)0.01876 (10)
Cl10.87074 (7)0.33484 (5)0.14547 (4)0.03170 (17)
Cl21.10937 (7)0.33479 (5)0.39080 (5)0.03539 (17)
O10.58286 (18)0.18564 (11)0.38732 (12)0.0238 (4)
O20.59661 (18)0.52345 (11)0.36945 (12)0.0245 (4)
N10.7675 (2)0.24265 (13)0.34819 (13)0.0172 (4)
N30.7766 (2)0.45103 (13)0.33782 (13)0.0177 (4)
N20.5051 (2)0.35734 (15)0.19970 (14)0.0257 (5)
C10.7779 (3)0.13552 (16)0.34031 (16)0.0193 (5)
C20.6654 (3)0.10073 (17)0.38508 (19)0.0267 (6)
H2A0.60960.04940.34680.027*
H2B0.70590.07590.44930.027*
C30.6578 (3)0.26111 (16)0.37190 (16)0.0177 (5)
C40.6652 (3)0.44283 (16)0.36183 (15)0.0169 (5)
C50.6871 (3)0.60246 (17)0.36051 (19)0.0268 (6)
H5A0.73040.63130.42250.027*
H5B0.63590.65290.31830.027*
C60.7948 (3)0.55571 (17)0.31880 (18)0.0244 (6)
C70.7456 (3)0.11024 (19)0.23679 (17)0.0309 (6)
H7A0.65250.13180.20520.031*
H7B0.75180.04050.22980.031*
H7C0.81160.14210.20860.031*
C80.9184 (3)0.10127 (19)0.3938 (2)0.0331 (7)
H8B0.98810.13170.36800.033*
H8A0.92370.03140.38780.033*
H8C0.93480.11850.46020.033*
C90.7624 (3)0.57103 (19)0.21363 (19)0.0373 (7)
H9B0.82590.53310.18800.037*
H9C0.77260.63920.20050.037*
H9A0.66800.55070.18440.037*
C100.9397 (3)0.5868 (2)0.3683 (2)0.0381 (7)
H10C0.95670.57570.43590.038*
H10B0.95060.65530.35680.038*
H10A1.00530.54960.34410.038*
C110.6263 (3)0.36275 (18)0.49971 (16)0.0267 (6)
H11A0.58050.30940.52250.027*
H11B0.59050.42380.51630.027*
H11C0.72530.35940.52870.027*
C120.4431 (3)0.35778 (17)0.34699 (16)0.0213 (5)
H12B0.40090.30280.37150.021*
H12A0.40520.41740.36670.021*
C130.5987 (2)0.35583 (16)0.39150 (15)0.0177 (5)
C140.4740 (3)0.35449 (17)0.10478 (16)0.0253 (6)
H140.54600.35880.07450.025*
C150.3403 (3)0.34549 (18)0.05079 (18)0.0332 (7)
H150.32060.34240.01570.033*
C160.2350 (3)0.34100 (19)0.09531 (19)0.0355 (7)
H160.14240.33490.05930.035*
C170.2649 (3)0.34528 (18)0.18914 (18)0.0263 (6)
H170.19370.34300.22020.026*
C180.4028 (3)0.35314 (16)0.24126 (16)0.0225 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Fe10.0160 (2)0.02093 (18)0.02094 (18)0.00010 (16)0.00769 (14)0.00049 (15)
Cl10.0378 (4)0.0372 (4)0.0234 (3)0.0015 (3)0.0140 (3)0.0002 (3)
Cl20.0185 (4)0.0517 (4)0.0342 (3)0.0017 (3)0.0038 (3)0.0017 (3)
O10.0232 (11)0.0157 (9)0.0363 (10)0.0017 (7)0.0145 (8)0.0011 (7)
O20.0225 (11)0.0166 (9)0.0380 (10)0.0018 (7)0.0141 (8)0.0010 (8)
N10.0174 (12)0.0160 (10)0.0184 (10)0.0008 (8)0.0048 (9)0.0005 (8)
N30.0167 (12)0.0157 (10)0.0215 (10)0.0015 (8)0.0063 (9)0.0002 (8)
N20.0259 (13)0.0276 (12)0.0242 (11)0.0005 (10)0.0076 (9)0.0008 (9)
C10.0208 (15)0.0156 (12)0.0207 (12)0.0002 (10)0.0045 (10)0.0012 (10)
C20.0315 (17)0.0166 (13)0.0353 (15)0.0001 (11)0.0148 (12)0.0009 (11)
C30.0171 (14)0.0187 (12)0.0166 (12)0.0017 (10)0.0033 (10)0.0024 (10)
C40.0181 (14)0.0161 (12)0.0158 (11)0.0008 (10)0.0033 (10)0.0013 (10)
C50.0275 (17)0.0151 (13)0.0398 (15)0.0049 (11)0.0123 (13)0.0007 (11)
C60.0264 (16)0.0152 (13)0.0338 (14)0.0021 (11)0.0118 (12)0.0006 (11)
C70.0393 (19)0.0257 (14)0.0288 (14)0.0030 (13)0.0112 (13)0.0042 (12)
C80.0264 (17)0.0239 (14)0.0455 (17)0.0023 (12)0.0033 (13)0.0018 (13)
C90.054 (2)0.0259 (15)0.0365 (16)0.0012 (14)0.0201 (15)0.0082 (13)
C100.0278 (18)0.0258 (15)0.062 (2)0.0077 (13)0.0142 (15)0.0048 (14)
C110.0331 (17)0.0281 (15)0.0203 (12)0.0014 (12)0.0098 (11)0.0004 (11)
C120.0181 (14)0.0210 (13)0.0257 (13)0.0014 (10)0.0076 (10)0.0008 (11)
C130.0174 (13)0.0191 (12)0.0186 (11)0.0002 (10)0.0083 (10)0.0001 (10)
C140.0310 (16)0.0229 (13)0.0224 (13)0.0020 (11)0.0078 (11)0.0033 (11)
C150.052 (2)0.0222 (13)0.0200 (13)0.0049 (14)0.0001 (12)0.0018 (12)
C160.0263 (16)0.0253 (14)0.0426 (16)0.0021 (13)0.0124 (13)0.0020 (13)
C170.0216 (15)0.0190 (13)0.0386 (15)0.0014 (11)0.0082 (12)0.0056 (12)
C180.0235 (15)0.0163 (12)0.0268 (13)0.0020 (11)0.0052 (11)0.0004 (10)
Geometric parameters (Å, º) top
Fe1—N12.0821 (19)C7—H7B0.9800
Fe1—N32.073 (2)C7—H7C0.9800
Fe1—Cl12.2633 (7)C8—H8B0.9800
Fe1—Cl22.2552 (9)C8—H8A0.9800
O1—C31.349 (3)C8—H8C0.9800
O1—C21.453 (3)C9—H9B0.9800
O2—C41.340 (3)C9—H9C0.9800
O2—C51.458 (3)C9—H9A0.9800
N1—C31.272 (3)C10—H10C0.9800
N1—C11.502 (3)C10—H10B0.9800
N3—C41.271 (3)C10—H10A0.9800
N3—C61.505 (3)C11—C131.551 (3)
N2—C181.335 (3)C11—H11A0.9800
N2—C141.354 (3)C11—H11B0.9800
C1—C81.508 (4)C11—H11C0.9800
C1—C71.518 (3)C12—C181.507 (3)
C1—C21.536 (3)C12—C131.535 (3)
C2—H2A0.9900C12—H12B0.9900
C2—H2B0.9900C12—H12A0.9900
C3—C131.507 (3)C14—C151.381 (4)
C4—C131.506 (3)C14—H140.9500
C5—C61.530 (3)C15—C161.392 (4)
C5—H5A0.9900C15—H150.9500
C5—H5B0.9900C16—C171.339 (4)
C6—C91.515 (4)C16—H160.9500
C6—C101.517 (4)C17—C181.408 (4)
C7—H7A0.9800C17—H170.9500
N3—Fe1—N188.85 (7)C1—C8—H8B109.5
N3—Fe1—Cl2113.73 (6)C1—C8—H8A109.5
N1—Fe1—Cl2111.27 (6)H8B—C8—H8A109.5
N3—Fe1—Cl1112.50 (6)C1—C8—H8C109.5
N1—Fe1—Cl1114.32 (6)H8B—C8—H8C109.5
Cl2—Fe1—Cl1113.81 (3)H8A—C8—H8C109.5
C3—O1—C2106.19 (18)C6—C9—H9B109.5
C4—O2—C5105.92 (18)C6—C9—H9C109.5
C3—N1—C1107.81 (19)H9B—C9—H9C109.5
C3—N1—Fe1126.70 (16)C6—C9—H9A109.5
C1—N1—Fe1124.42 (15)H9B—C9—H9A109.5
C4—N3—C6107.4 (2)H9C—C9—H9A109.5
C4—N3—Fe1126.74 (16)C6—C10—H10C109.5
C6—N3—Fe1124.51 (15)C6—C10—H10B109.5
C18—N2—C14118.6 (2)H10C—C10—H10B109.5
N1—C1—C8110.4 (2)C6—C10—H10A109.5
N1—C1—C7107.91 (19)H10C—C10—H10A109.5
C8—C1—C7112.1 (2)H10B—C10—H10A109.5
N1—C1—C2101.83 (18)C13—C11—H11A109.5
C8—C1—C2112.1 (2)C13—C11—H11B109.5
C7—C1—C2111.9 (2)H11A—C11—H11B109.5
O1—C2—C1104.33 (18)C13—C11—H11C109.5
O1—C2—H2A110.9H11A—C11—H11C109.5
C1—C2—H2A110.9H11B—C11—H11C109.5
O1—C2—H2B110.9C18—C12—C13114.2 (2)
C1—C2—H2B110.9C18—C12—H12B108.7
H2A—C2—H2B108.9C13—C12—H12B108.7
N1—C3—O1117.2 (2)C18—C12—H12A108.7
N1—C3—C13130.4 (2)C13—C12—H12A108.7
O1—C3—C13112.4 (2)H12B—C12—H12A107.6
N3—C4—O2117.6 (2)C4—C13—C3114.71 (19)
N3—C4—C13130.5 (2)C4—C13—C12110.27 (19)
O2—C4—C13111.7 (2)C3—C13—C12110.26 (19)
O2—C5—C6104.15 (18)C4—C13—C11106.07 (19)
O2—C5—H5A110.9C3—C13—C11106.22 (19)
C6—C5—H5A110.9C12—C13—C11109.02 (19)
O2—C5—H5B110.9N2—C14—C15121.7 (2)
C6—C5—H5B110.9N2—C14—H14119.2
H5A—C5—H5B108.9C15—C14—H14119.2
N3—C6—C9108.9 (2)C14—C15—C16119.0 (2)
N3—C6—C10109.7 (2)C14—C15—H15120.5
C9—C6—C10111.9 (2)C16—C15—H15120.5
N3—C6—C5101.67 (19)C17—C16—C15119.7 (3)
C9—C6—C5111.6 (2)C17—C16—H16120.2
C10—C6—C5112.5 (2)C15—C16—H16120.2
C1—C7—H7A109.5C16—C17—C18119.3 (3)
C1—C7—H7B109.5C16—C17—H17120.3
H7A—C7—H7B109.5C18—C17—H17120.3
C1—C7—H7C109.5N2—C18—C17121.8 (2)
H7A—C7—H7C109.5N2—C18—C12116.3 (2)
H7B—C7—H7C109.5C17—C18—C12121.9 (2)
N3—Fe1—N1—C39.1 (2)C4—N3—C6—C9105.0 (2)
Cl2—Fe1—N1—C3124.2 (2)Fe1—N3—C6—C962.7 (3)
Cl1—Fe1—N1—C3105.2 (2)C4—N3—C6—C10132.2 (2)
N3—Fe1—N1—C1175.79 (18)Fe1—N3—C6—C1060.1 (3)
Cl2—Fe1—N1—C169.11 (18)C4—N3—C6—C512.9 (3)
Cl1—Fe1—N1—C161.53 (18)Fe1—N3—C6—C5179.43 (15)
N1—Fe1—N3—C49.9 (2)O2—C5—C6—N317.1 (3)
Cl2—Fe1—N3—C4122.71 (19)O2—C5—C6—C998.8 (2)
Cl1—Fe1—N3—C4106.0 (2)O2—C5—C6—C10134.4 (2)
N1—Fe1—N3—C6175.18 (19)N3—C4—C13—C313.5 (4)
Cl2—Fe1—N3—C672.03 (19)O2—C4—C13—C3171.6 (2)
Cl1—Fe1—N3—C659.23 (19)N3—C4—C13—C12138.7 (3)
C3—N1—C1—C8130.6 (2)O2—C4—C13—C1246.5 (2)
Fe1—N1—C1—C860.6 (2)N3—C4—C13—C11103.4 (3)
C3—N1—C1—C7106.6 (2)O2—C4—C13—C1171.4 (2)
Fe1—N1—C1—C762.3 (2)N1—C3—C13—C412.4 (4)
C3—N1—C1—C211.4 (3)O1—C3—C13—C4171.2 (2)
Fe1—N1—C1—C2179.80 (15)N1—C3—C13—C12137.6 (3)
C3—O1—C2—C114.9 (2)O1—C3—C13—C1246.0 (2)
N1—C1—C2—O115.6 (2)N1—C3—C13—C11104.4 (3)
C8—C1—C2—O1133.6 (2)O1—C3—C13—C1172.0 (2)
C7—C1—C2—O199.4 (2)C18—C12—C13—C463.0 (2)
C1—N1—C3—O12.4 (3)C18—C12—C13—C364.7 (2)
Fe1—N1—C3—O1170.87 (14)C18—C12—C13—C11179.02 (19)
C1—N1—C3—C13178.6 (2)C18—N2—C14—C151.3 (4)
Fe1—N1—C3—C1312.9 (4)N2—C14—C15—C161.2 (4)
C2—O1—C3—N18.5 (3)C14—C15—C16—C170.1 (4)
C2—O1—C3—C13168.4 (2)C15—C16—C17—C180.7 (4)
C6—N3—C4—O23.3 (3)C14—N2—C18—C170.4 (4)
Fe1—N3—C4—O2170.57 (15)C14—N2—C18—C12179.3 (2)
C6—N3—C4—C13177.9 (2)C16—C17—C18—N20.6 (4)
Fe1—N3—C4—C1314.8 (4)C16—C17—C18—C12179.7 (2)
C5—O2—C4—N38.6 (3)C13—C12—C18—N26.2 (3)
C5—O2—C4—C13166.98 (19)C13—C12—C18—C17174.1 (2)
C4—O2—C5—C616.0 (2)

Experimental details

Crystal data
Chemical formula[FeCl2(C18H25N3O2)]
Mr442.16
Crystal system, space groupMonoclinic, P21/c
Temperature (K)173
a, b, c (Å)10.102 (2), 13.925 (3), 14.764 (2)
β (°) 105.27 (1)
V3)2003.5 (6)
Z4
Radiation typeMo Kα
µ (mm1)1.04
Crystal size (mm)0.20 × 0.10 × 0.10
Data collection
DiffractometerBruker–Nonius KappaCCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2001)
Tmin, Tmax0.820, 0.903
No. of measured, independent and
observed [I > 2σ(I)] reflections
16483, 4578, 3033
Rint0.054
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.041, 0.083, 1.01
No. of reflections4578
No. of parameters240
No. of restraints0
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.34, 0.30

Computer programs: COLLECT (Nonius, 1999), DIRAX/LSQ (Duisenberg et al., 2000), EVALCCD (Duisenberg et al., 2003), SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012), WinGX (Farrugia, 2012).

Acknowledgements top

The authors thank the Centro Interdipartimentale di Metodologie Chimico–Fisiche, Università degli Studi di Napoli "Federico II" for X-ray facilities.

references
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