Dichlorobis(2-formyl­pyridine­anil)­iron(II) aceto­nitrile solvate

The structure of the title compound {systematic name: di­chloro­bis­[2-(phenyl­imino­methyl)­pyridine]­iron(II) aceto­nitrile solvate}, cis-(2-C₅H₄NCH=NPh)₂FeCl₂·C₂H₃N, consists of an iron centre bound by two bidentate pyridyl­imine ligands and two cis-disposed chloride ligands.

Key indicators

• Single-crystal X-ray study
• T = 150 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.032
• wR factor = 0.083
• Data-to-parameter ratio = 14.1

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry

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S1. Comment

The synthesis of divalent late transition metal complexes supported by chelating multidentate ligands containing both the imino and pyridine moieties has been the subject of considerable recent research activity due, in part, to their connection to olefin polymerization catalysis (Gibson & Spitzmesser, 2003). In particular, the application of group 10 metals supported by iminopyridine ligands (Laine et al., 1999) and group 8 metals by bis(imino)pyridine ligands (Britovsek et al., 1998) has allowed access to highly active ethylene polymerization catalysts capable of producing a wide variety of polymeric materials.

Here, we report the synthesis and the crystal structure of cis-(2-C₅H₄NCH═NPh)₂FeCl₂·C₂H₃N, (I). The positive FAB mass spectrum exhibits a molecular ion peak along with a fragmentation peak corresponding to the loss of chloride from the molecular ion.

The X-ray analysis of (I) shows a distorted octahedral complex in which the Fe atom is bound to two cis-coordinated N,N'-chelating ligands [the pyridyl N atoms being trans; bite angle = 159.60 (6)°] and two chlorides. The Fe—N(pyridine) distances [2.1744 (15) and 2.1799 (16) Å] are similar and notably shorter than the Fe—N(imine) distances [Fe1—N4 = 2.2474 (16) Å and Fe1—N2 = 2.3144 (14) Å]. The explanation for the disparity in the Fe—N(imine) distances is uncertain but it is worthy of note that the corresponding trans Fe—Cl distances [Fe1—Cl1 = 2.3796 (6) Å and Fe1—Cl2 = 2.4120 (5) Å] are also markedly different, with the shorter Fe—N(imine) distance (Fe1—N4) being accompanied by a longer trans Fe—Cl distance (Fe1—Cl1) and vice versa. The two imine linkages, C6—N2 and C18—N4, are both short, reflecting a retention of their double-bond character. The phenyl rings of each ligand are similarly oriented with respect to the pyridyl-imine N—C—C—N planes [43.90 (9) and 46.46 (10)°]. There are no intermolecular packing interactions of note.

S2. Experimental

Under an atmosphere of nitrogen, a suspension of iron(II) chloride (0.222 g, 1.75 mmol) in tetrahydrofuran (30 ml) was cooled to 195 K and 2-formylpyridineanil (0.600 g, 3.30 mmol) was added to this solution via a solids addition tube. The dark green solution mixture was allowed to reach room temperature and then stirred overnight. The volatiles were removed under reduced pressure and the remaining solid was extracted into acetonitrile (30 ml), stirred for 3 h and then filtered. The solution was layered with hexane (60 ml) and left to crystallize at 248 K. After 3 d, dark green crystals suitable for single-crystal X-ray diffraction analysis were obtained (0.200 g, 24% yield).

S3. Refinement

All H atoms were refined using a riding model, with bond lengths of 0.98 Å (solvent molecule) and 0.95 Å (all others). For methyl H atoms, U_iso(H) = 1.5U_eq(parent); for all other H atoms, U_iso(H) = 1.2U_eq(parent).

Computing details

Data collection: SMART (Bruker, 1997); cell refinement: SMART; data reduction: SAINT (Bruker, 1999); program(s) used to solve structure: SHELXTL (Bruker, 2000); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Figures

Fig. 1. The molecular structure of (I), showing the atom-numbering scheme and 50% displacement ellipsoids. H atoms are drawn as spheres of arbitary radius. For clarity, the acetonitrile solvent molecule has been omitted.

dichlorobis[2-(phenyliminomethyl)pyridine]iron(II) acetonitrile solvate

Crystal data

[FeCl2(C12H10N2)2]·C2H3N	F(000) = 1096
Mr = 532.24	Dx = 1.427 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 12.7838 (7) Å	Cell parameters from 7807 reflections
b = 14.8194 (8) Å	θ = 2.2–28.4°
c = 13.8905 (8) Å	µ = 0.85 mm^−1
β = 109.677 (10)°	T = 150 K
V = 2477.9 (2) Å^3	Plate, black
Z = 4	0.39 × 0.26 × 0.09 mm

Data collection

Bruker CCD area-detector diffractometer	4348 independent reflections
Radiation source: fine-focus sealed tube	3811 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.027
ϕ and ω scans	θmax = 25.0°, θmin = 1.7°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −15→15
Tmin = 0.715, Tmax = 0.928	k = −17→17
15046 measured reflections	l = −16→16

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)] = 0.033	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.083	H-atom parameters constrained
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0513P)^2 + 0.2129P] where P = (Fo^2 + 2Fc^2)/3
4348 reflections	(Δ/σ)max = 0.002
308 parameters	Δρmax = 0.47 e Å^−3
0 restraints	Δρmin = −0.24 e Å^−3

Special details

Experimental. absorption correction based on 11055 reflections (SADABS); R_int 0.065 before correction and 0.025 after.

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
Fe1	0.83220 (2)	0.174761 (16)	0.61116 (2)	0.02300 (10)
Cl1	0.71892 (4)	0.15322 (3)	0.43755 (4)	0.02874 (13)
Cl2	0.87941 (4)	0.33207 (3)	0.60809 (4)	0.03093 (14)
N1	0.98966 (13)	0.13050 (10)	0.59950 (11)	0.0240 (3)
N2	0.84753 (13)	0.02197 (10)	0.64776 (12)	0.0227 (3)
N3	0.68955 (14)	0.18127 (9)	0.66338 (13)	0.0267 (4)
N4	0.90188 (14)	0.16984 (9)	0.78276 (12)	0.0251 (4)
C1	1.05732 (17)	0.18082 (12)	0.56657 (15)	0.0286 (5)
H1	1.0358	0.2410	0.5455	0.034*
C2	1.15738 (17)	0.14935 (13)	0.56176 (16)	0.0313 (5)
H2	1.2025	0.1871	0.5367	0.038*
C3	1.19089 (17)	0.06285 (13)	0.59358 (15)	0.0318 (5)
H3	1.2599	0.0404	0.5921	0.038*
C4	1.12186 (16)	0.00938 (13)	0.62770 (15)	0.0292 (4)
H4	1.1423	−0.0508	0.6496	0.035*
C5	1.02270 (16)	0.04513 (12)	0.62938 (14)	0.0239 (4)
C6	0.94327 (16)	−0.00955 (12)	0.65872 (14)	0.0260 (4)
H6	0.9631	−0.0684	0.6859	0.031*
C7	0.76967 (16)	−0.03182 (11)	0.67573 (15)	0.0243 (4)
C8	0.65988 (16)	−0.02873 (12)	0.61257 (16)	0.0281 (4)
H8	0.6394	0.0062	0.5517	0.034*
C9	0.58003 (18)	−0.07636 (13)	0.63796 (17)	0.0349 (5)
H9	0.5047	−0.0742	0.5943	0.042*
C10	0.60912 (19)	−0.12699 (13)	0.72640 (19)	0.0390 (5)
H10	0.5540	−0.1594	0.7440	0.047*
C11	0.7191 (2)	−0.13026 (14)	0.78943 (18)	0.0384 (5)
H11	0.7393	−0.1653	0.8502	0.046*
C12	0.79993 (17)	−0.08286 (12)	0.76466 (15)	0.0298 (5)
H12	0.8753	−0.0853	0.8081	0.036*
C13	0.58320 (18)	0.18693 (12)	0.60349 (18)	0.0323 (5)
H13	0.5666	0.1987	0.5327	0.039*
C14	0.49599 (19)	0.17618 (13)	0.6411 (2)	0.0403 (6)
H14	0.4212	0.1804	0.5964	0.048*
C15	0.5189 (2)	0.15941 (14)	0.7431 (2)	0.0426 (6)
H15	0.4603	0.1507	0.7698	0.051*
C16	0.62814 (19)	0.15542 (13)	0.80658 (18)	0.0366 (5)
H16	0.6462	0.1449	0.8778	0.044*
C17	0.71115 (18)	0.16717 (12)	0.76389 (16)	0.0290 (5)
C18	0.82836 (18)	0.16341 (12)	0.82645 (16)	0.0295 (5)
H18	0.8499	0.1563	0.8985	0.035*
C19	1.01578 (17)	0.15712 (12)	0.84049 (15)	0.0275 (4)
C20	1.09401 (17)	0.21387 (13)	0.82264 (15)	0.0311 (5)
H20	1.0706	0.2630	0.7765	0.037*
C21	1.20575 (19)	0.19840 (15)	0.87234 (17)	0.0373 (5)
H21	1.2593	0.2375	0.8608	0.045*
C22	1.24008 (19)	0.12645 (16)	0.93868 (17)	0.0431 (6)
H22	1.3171	0.1161	0.9728	0.052*
C23	1.1626 (2)	0.06962 (15)	0.95529 (18)	0.0446 (6)
H23	1.1864	0.0197	1.0003	0.054*
C24	1.05092 (19)	0.08466 (13)	0.90705 (16)	0.0365 (5)
H24	0.9979	0.0455	0.9192	0.044*
N5	0.51858 (18)	0.38481 (14)	0.48449 (18)	0.0540 (6)
C25	0.5740 (2)	0.40563 (15)	0.5641 (2)	0.0405 (5)
C26	0.6448 (2)	0.43209 (17)	0.66485 (18)	0.0489 (6)
H26A	0.7226	0.4215	0.6714	0.073*
H26B	0.6262	0.3964	0.7163	0.073*
H26C	0.6338	0.4963	0.6753	0.073*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Fe1	0.02561 (18)	0.02037 (16)	0.02390 (17)	0.00153 (10)	0.00949 (13)	0.00115 (10)
Cl1	0.0319 (3)	0.0278 (2)	0.0249 (3)	0.00430 (19)	0.0074 (2)	0.00137 (19)
Cl2	0.0382 (3)	0.0203 (2)	0.0355 (3)	0.00026 (19)	0.0140 (2)	0.00062 (19)
N1	0.0266 (9)	0.0228 (8)	0.0222 (9)	−0.0004 (6)	0.0078 (7)	−0.0019 (6)
N2	0.0251 (9)	0.0210 (7)	0.0200 (8)	−0.0016 (6)	0.0051 (7)	−0.0017 (6)
N3	0.0313 (10)	0.0199 (8)	0.0306 (10)	−0.0004 (7)	0.0128 (8)	−0.0033 (7)
N4	0.0321 (10)	0.0195 (8)	0.0242 (9)	−0.0034 (6)	0.0103 (8)	−0.0030 (6)
C1	0.0357 (12)	0.0243 (10)	0.0274 (11)	−0.0010 (8)	0.0126 (10)	0.0002 (8)
C2	0.0327 (12)	0.0336 (11)	0.0314 (12)	−0.0039 (9)	0.0157 (10)	−0.0025 (9)
C3	0.0266 (11)	0.0360 (11)	0.0336 (12)	0.0014 (9)	0.0112 (10)	−0.0067 (9)
C4	0.0294 (11)	0.0259 (10)	0.0302 (11)	0.0033 (8)	0.0072 (9)	−0.0024 (8)
C5	0.0267 (10)	0.0219 (9)	0.0212 (10)	0.0004 (8)	0.0056 (8)	−0.0033 (7)
C6	0.0314 (11)	0.0205 (9)	0.0248 (11)	0.0010 (8)	0.0075 (9)	−0.0016 (8)
C7	0.0301 (11)	0.0166 (9)	0.0278 (11)	0.0002 (7)	0.0117 (9)	−0.0029 (8)
C8	0.0309 (11)	0.0219 (9)	0.0293 (11)	0.0009 (8)	0.0073 (9)	−0.0001 (8)
C9	0.0277 (12)	0.0302 (10)	0.0446 (13)	−0.0045 (9)	0.0093 (10)	−0.0047 (10)
C10	0.0408 (14)	0.0289 (11)	0.0548 (15)	−0.0065 (9)	0.0259 (12)	−0.0003 (10)
C11	0.0517 (15)	0.0303 (11)	0.0362 (13)	−0.0019 (10)	0.0190 (12)	0.0074 (9)
C12	0.0319 (12)	0.0254 (10)	0.0294 (11)	0.0002 (8)	0.0069 (10)	0.0016 (8)
C13	0.0338 (13)	0.0235 (10)	0.0412 (13)	0.0025 (8)	0.0149 (11)	−0.0027 (9)
C14	0.0307 (13)	0.0349 (12)	0.0563 (16)	0.0013 (9)	0.0160 (12)	−0.0077 (10)
C15	0.0439 (15)	0.0344 (12)	0.0626 (17)	−0.0051 (10)	0.0353 (14)	−0.0103 (11)
C16	0.0477 (15)	0.0278 (10)	0.0431 (14)	−0.0063 (9)	0.0271 (12)	−0.0067 (9)
C17	0.0381 (13)	0.0209 (9)	0.0324 (12)	−0.0038 (8)	0.0178 (10)	−0.0079 (8)
C18	0.0431 (13)	0.0235 (10)	0.0238 (11)	−0.0054 (8)	0.0135 (10)	−0.0048 (8)
C19	0.0361 (12)	0.0255 (9)	0.0205 (10)	−0.0029 (8)	0.0089 (9)	−0.0074 (8)
C20	0.0375 (13)	0.0285 (10)	0.0277 (11)	−0.0034 (9)	0.0116 (10)	−0.0041 (9)
C21	0.0339 (13)	0.0426 (12)	0.0359 (13)	−0.0067 (10)	0.0125 (11)	−0.0091 (10)
C22	0.0353 (13)	0.0491 (13)	0.0370 (13)	0.0045 (11)	0.0016 (11)	−0.0101 (11)
C23	0.0520 (16)	0.0367 (12)	0.0355 (13)	0.0058 (11)	0.0020 (12)	0.0034 (10)
C24	0.0453 (14)	0.0294 (11)	0.0310 (12)	−0.0050 (9)	0.0079 (11)	0.0013 (9)
N5	0.0513 (14)	0.0601 (14)	0.0495 (14)	0.0160 (11)	0.0155 (12)	0.0001 (11)
C25	0.0431 (15)	0.0375 (12)	0.0463 (15)	0.0118 (10)	0.0221 (13)	0.0066 (11)
C26	0.0509 (16)	0.0537 (15)	0.0427 (15)	0.0050 (12)	0.0166 (13)	0.0005 (12)

Geometric parameters (Å, º)

Fe1—N1	2.1744 (15)	C10—H10	0.9500
Fe1—N3	2.1799 (16)	C11—C12	1.385 (3)
Fe1—N4	2.2474 (16)	C11—H11	0.9500
Fe1—N2	2.3144 (14)	C12—H12	0.9500
Fe1—Cl1	2.3796 (6)	C13—C14	1.390 (3)
Fe1—Cl2	2.4120 (5)	C13—H13	0.9500
N1—C1	1.334 (2)	C14—C15	1.370 (3)
N1—C5	1.354 (2)	C14—H14	0.9500
N2—C6	1.270 (2)	C15—C16	1.379 (3)
N2—C7	1.427 (2)	C15—H15	0.9500
N3—C13	1.336 (3)	C16—C17	1.390 (3)
N3—C17	1.345 (3)	C16—H16	0.9500
N4—C18	1.283 (3)	C17—C18	1.458 (3)
N4—C19	1.419 (3)	C18—H18	0.9500
C1—C2	1.384 (3)	C19—C24	1.389 (3)
C1—H1	0.9500	C19—C20	1.391 (3)
C2—C3	1.376 (3)	C20—C21	1.380 (3)
C2—H2	0.9500	C20—H20	0.9500
C3—C4	1.383 (3)	C21—C22	1.381 (3)
C3—H3	0.9500	C21—H21	0.9500
C4—C5	1.381 (3)	C22—C23	1.378 (3)
C4—H4	0.9500	C22—H22	0.9500
C5—C6	1.460 (2)	C23—C24	1.375 (3)
C6—H6	0.9500	C23—H23	0.9500
C7—C8	1.383 (3)	C24—H24	0.9500
C7—C12	1.388 (3)	N5—C25	1.137 (3)
C8—C9	1.381 (3)	C25—C26	1.442 (4)
C8—H8	0.9500	C26—H26A	0.9800
C9—C10	1.379 (3)	C26—H26B	0.9800
C9—H9	0.9500	C26—H26C	0.9800
C10—C11	1.385 (3)
N1—Fe1—N3	159.60 (6)	C8—C9—H9	119.8
N1—Fe1—N4	91.31 (6)	C9—C10—C11	119.61 (19)
N3—Fe1—N4	74.08 (6)	C9—C10—H10	120.2
N1—Fe1—N2	73.10 (5)	C11—C10—H10	120.2
N3—Fe1—N2	89.35 (5)	C10—C11—C12	120.6 (2)
N4—Fe1—N2	76.19 (5)	C10—C11—H11	119.7
N1—Fe1—Cl1	98.44 (4)	C12—C11—H11	119.7
N3—Fe1—Cl1	92.94 (5)	C11—C12—C7	119.33 (19)
N4—Fe1—Cl1	163.56 (4)	C11—C12—H12	120.3
N2—Fe1—Cl1	93.96 (4)	C7—C12—H12	120.3
N1—Fe1—Cl2	92.68 (4)	N3—C13—C14	122.4 (2)
N3—Fe1—Cl2	101.86 (4)	N3—C13—H13	118.8
N4—Fe1—Cl2	92.17 (4)	C14—C13—H13	118.8
N2—Fe1—Cl2	161.12 (4)	C15—C14—C13	119.4 (2)
Cl1—Fe1—Cl2	100.504 (19)	C15—C14—H14	120.3
C1—N1—C5	117.14 (16)	C13—C14—H14	120.3
C1—N1—Fe1	125.46 (13)	C14—C15—C16	119.1 (2)
C5—N1—Fe1	117.39 (12)	C14—C15—H15	120.4
C6—N2—C7	119.60 (15)	C16—C15—H15	120.4
C6—N2—Fe1	113.14 (12)	C15—C16—C17	118.4 (2)
C7—N2—Fe1	126.23 (11)	C15—C16—H16	120.8
C13—N3—C17	117.79 (18)	C17—C16—H16	120.8
C13—N3—Fe1	125.82 (14)	N3—C17—C16	122.9 (2)
C17—N3—Fe1	115.85 (14)	N3—C17—C18	115.79 (17)
C18—N4—C19	119.93 (17)	C16—C17—C18	121.3 (2)
C18—N4—Fe1	114.35 (14)	N4—C18—C17	119.01 (19)
C19—N4—Fe1	124.66 (12)	N4—C18—H18	120.5
N1—C1—C2	122.99 (18)	C17—C18—H18	120.5
N1—C1—H1	118.5	C24—C19—C20	119.7 (2)
C2—C1—H1	118.5	C24—C19—N4	121.29 (18)
C3—C2—C1	119.41 (18)	C20—C19—N4	118.79 (17)
C3—C2—H2	120.3	C21—C20—C19	119.7 (2)
C1—C2—H2	120.3	C21—C20—H20	120.2
C2—C3—C4	118.57 (18)	C19—C20—H20	120.2
C2—C3—H3	120.7	C20—C21—C22	120.3 (2)
C4—C3—H3	120.7	C20—C21—H21	119.8
C5—C4—C3	118.75 (18)	C22—C21—H21	119.8
C5—C4—H4	120.6	C23—C22—C21	119.9 (2)
C3—C4—H4	120.6	C23—C22—H22	120.0
N1—C5—C4	123.13 (17)	C21—C22—H22	120.0
N1—C5—C6	115.45 (16)	C24—C23—C22	120.4 (2)
C4—C5—C6	121.34 (17)	C24—C23—H23	119.8
N2—C6—C5	119.66 (17)	C22—C23—H23	119.8
N2—C6—H6	120.2	C23—C24—C19	120.0 (2)
C5—C6—H6	120.2	C23—C24—H24	120.0
C8—C7—C12	120.12 (17)	C19—C24—H24	120.0
C8—C7—N2	117.43 (16)	N5—C25—C26	179.6 (3)
C12—C7—N2	122.39 (17)	C25—C26—H26A	109.5
C9—C8—C7	120.05 (19)	C25—C26—H26B	109.5
C9—C8—H8	120.0	H26A—C26—H26B	109.5
C7—C8—H8	120.0	C25—C26—H26C	109.5
C10—C9—C8	120.3 (2)	H26A—C26—H26C	109.5
C10—C9—H9	119.8	H26B—C26—H26C	109.5