{2-[(2,5-Dimethyl­phen­yl)imino­methyl]pyridine-κ²N,N′}diiodidozinc(II)

In the mol­ecule of the title compound, [ZnI₂(C₁₄H₁₄N₂)], the Zn atom is four-coordinated in a distorted tetra­hedral geometry by two N atoms of the Schiff base ligand and by two I atoms. The benzene and pyridine rings are oriented at a dihedral angle of 70.75 (3)°. The five-membered ring has an envelope conformation. There is a weak π–π inter­action between benzene rings, with a centroid-to-centroid distance of 3.975 (4) Å.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.009 Å
• R factor = 0.072
• wR factor = 0.230
• Data-to-parameter ratio = 26.2

checkCIF/PLATON results

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PLAT380_ALERT_4_C Check Incorrectly? Oriented X(sp2)-Methyl Moiety        C13

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S1. Comment

Transition metal compounds containing Schiff base ligands have been of great interest for many years. These compounds play an important role in the development of coordination chemistry (Gibson et al., 2007). Aryl-substituted iminopyridine complexes have emerged as a powerful class of catalysts for a host of important bond-forming reactions including olefin polymerization (Ittel et al., 2000; Gibson & Spitzmesser, 2003), hydrogenation and hydrosilation (Bart et al., 2004). It is also now well established that iminopyridines are both redox (Sugiyama et al., 2004) and chemically active ligands (Kooistra et al., 2004) participating in electron transfer, addition reactions and deprotonation chemistry (Bouwkamp et al., 2006). We report herein the crystal structure of the title compound.

In the molecule of the title compound (Fig. 1), the Zn atom is four-coordinated in distorted tetrahedral geometry (Table 1) by two N atoms of the Schiff base ligand, and two I atoms. The bond angles around the Zn atom deviate from the ideal tetrahedral geometry (Dehghanpour et al., 2007). Rings A (N1/C1–C5) and B (C7/C8/C10/C11/C12/C14) are, of course, planar, and they are oriented at a dihedral angle of 70.75 (3)°. Ring C (Zn1/N1/N2/C5/C6) has envelope conformation, with N2 atom displaced by 0.104 (3) Å from the plane of the other ring atoms. The weak π–π interaction between B rings CgB···CgBⁱ [symmetry code: (iv) 1 - x, 1 - y, 1 - z] may stabilize the structure, with a centroid–centroid distance of 3.975 (4) Å.

Related literature

For general background, see: Gibson et al. (2007); Ittel et al. (2000); Gibson & Spitzmesser (2003); Bart et al. (2004); Sugiyama et al. (2004); Kooistra et al. (2004); Bouwkamp et al. (2006). For related literature, see: Dehghanpour et al. (2007).

S2. Experimental

For the preparation of the title compound, (2,5-dimethyl-N-phenyl)(pyridine-2-yl)methanimine (21.0 mg, 0.1 mmol), and ZnI₂ (31.9 mg, 0.1 mmol) were dissolved in acetonitrile (50 ml). The mixture was stirred for 10 min at room temperature. The resulting solution was left in air for a few days, giving yellow crystals of the title compound (yield; 79%). Calc.: C 31.75 H 2.67, N 5.29%, found: C 31.79, H 2.49, N 5.31%.

S3. Refinement

H atoms were positioned geometrically, with C—H = 0.93 and 0.96 Å for aromatic and methyl H, and constrained to ride on their parent atoms, with U_iso(H) = 1.2U_eq(C).

Computing details

Data collection: X-AREA (Stoe & Cie, 2005); cell refinement: X-AREA (Stoe & Cie, 2005); data reduction: X-RED (Stoe & Cie, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures

Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.

{2-[(2,5-Dimethylphenyl)iminomethyl]pyridine-κ²N,N'}diiodidozinc(II)

Crystal data

[ZnI2(C14H14N2)]	F(000) = 992
Mr = 529.46	Dx = 2.068 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2112 reflections
a = 11.467 (5) Å	θ = 2.5–29.4°
b = 9.627 (4) Å	µ = 5.06 mm^−1
c = 15.868 (6) Å	T = 298 K
β = 103.88 (3)°	Block, yellow
V = 1700.6 (12) Å^3	0.5 × 0.4 × 0.25 mm
Z = 4

Data collection

Stoe IPDSII diffractometer	4035 reflections with I > 2σ(I)
rotation method scans	Rint = 0.098
Absorption correction: numerical [X-RED and X-SHAPE (Stoe & Cie, 2005)]	θmax = 29.4°, θmin = 2.5°
Tmin = 0.100, Tmax = 0.280	h = −15→11
10947 measured reflections	k = −11→13
4498 independent reflections	l = −21→21

Refinement

Refinement on F^2	0 restraints
Least-squares matrix: full	H-atom parameters constrained
R[F^2 > 2σ(F^2)] = 0.071	w = 1/[σ^2(Fo^2) + (0.1439P)^2 + 2.419P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.230	(Δ/σ)max = 0.007
S = 1.12	Δρmax = 1.97 e Å^−3
4498 reflections	Δρmin = −1.66 e Å^−3
172 parameters

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.

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

	x	y	z	Uiso*/Ueq
Zn1	0.83553 (6)	0.25679 (7)	0.02157 (4)	0.0406 (2)
I1	0.69958 (5)	0.45620 (5)	0.03661 (4)	0.0622 (2)
I2	0.87622 (5)	0.19974 (6)	−0.12580 (3)	0.0617 (2)
N1	0.9989 (4)	0.2665 (5)	0.1106 (3)	0.0400 (9)
N2	0.8103 (4)	0.1007 (5)	0.1083 (3)	0.0366 (8)
C1	1.0919 (6)	0.3467 (9)	0.1080 (5)	0.0524 (14)
H1	1.086	0.4083	0.062	0.063*
C2	1.1962 (6)	0.3412 (9)	0.1712 (5)	0.0590 (18)
H2	1.2614	0.3967	0.1681	0.071*
C3	1.2026 (6)	0.2495 (9)	0.2411 (5)	0.0596 (19)
H3	1.2721	0.2453	0.2856	0.072*
C4	1.1071 (5)	0.1665 (8)	0.2440 (4)	0.0498 (13)
H4	1.1104	0.1042	0.2893	0.06*
C5	1.0055 (5)	0.1786 (6)	0.1771 (4)	0.0411 (11)
C6	0.8989 (5)	0.0951 (6)	0.1752 (4)	0.0412 (11)
H6	0.8952	0.0384	0.2219	0.049*
C7	0.7036 (5)	0.0265 (5)	0.1120 (3)	0.0356 (9)
C8	0.6663 (5)	−0.0814 (6)	0.0540 (3)	0.0377 (10)
C9	0.7345 (7)	−0.1256 (8)	−0.0114 (5)	0.0531 (14)
H9A	0.8136	−0.1554	0.0183	0.064*
H9B	0.7404	−0.0488	−0.0487	0.064*
H9C	0.693	−0.201	−0.0455	0.064*
C10	0.5634 (5)	−0.1522 (6)	0.0595 (4)	0.0440 (12)
H10	0.5352	−0.2247	0.0213	0.053*
C11	0.5023 (5)	−0.1160 (7)	0.1214 (5)	0.0495 (13)
H11	0.4335	−0.1652	0.1241	0.059*
C12	0.5402 (5)	−0.0092 (8)	0.1791 (4)	0.0491 (13)
C13	0.4725 (8)	0.0300 (13)	0.2483 (7)	0.076 (3)
H13A	0.4453	0.1244	0.2396	0.091*
H13B	0.5253	0.0207	0.305	0.091*
H13C	0.4047	−0.0304	0.2435	0.091*
C14	0.6415 (5)	0.0638 (6)	0.1732 (4)	0.0416 (11)
H14	0.668	0.138	0.2104	0.05*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Zn1	0.0414 (4)	0.0406 (4)	0.0392 (4)	−0.0024 (2)	0.0082 (3)	0.0058 (2)
I1	0.0607 (3)	0.0455 (3)	0.0819 (4)	0.00774 (18)	0.0200 (3)	0.0016 (2)
I2	0.0745 (4)	0.0713 (4)	0.0442 (3)	0.0013 (2)	0.0239 (2)	0.00481 (18)
N1	0.036 (2)	0.038 (2)	0.047 (2)	−0.0030 (17)	0.0124 (18)	−0.0020 (18)
N2	0.041 (2)	0.033 (2)	0.0357 (19)	0.0000 (16)	0.0107 (16)	0.0014 (16)
C1	0.048 (3)	0.060 (4)	0.052 (3)	−0.015 (3)	0.019 (3)	−0.006 (3)
C2	0.039 (3)	0.076 (5)	0.064 (4)	−0.011 (3)	0.016 (3)	−0.030 (4)
C3	0.039 (3)	0.079 (5)	0.055 (4)	0.001 (3)	0.001 (3)	−0.032 (4)
C4	0.040 (3)	0.054 (3)	0.050 (3)	0.003 (2)	0.001 (2)	−0.006 (3)
C5	0.041 (2)	0.040 (3)	0.041 (2)	0.000 (2)	0.006 (2)	−0.007 (2)
C6	0.040 (2)	0.037 (2)	0.044 (3)	0.0001 (19)	0.005 (2)	0.006 (2)
C7	0.036 (2)	0.031 (2)	0.037 (2)	0.0000 (17)	0.0042 (17)	0.0039 (17)
C8	0.045 (2)	0.033 (2)	0.034 (2)	0.0013 (19)	0.0083 (19)	0.0027 (18)
C9	0.066 (4)	0.048 (3)	0.050 (3)	−0.003 (3)	0.023 (3)	−0.011 (3)
C10	0.040 (2)	0.036 (2)	0.051 (3)	−0.005 (2)	0.002 (2)	0.001 (2)
C11	0.037 (2)	0.050 (3)	0.060 (3)	−0.002 (2)	0.008 (2)	0.006 (3)
C12	0.033 (2)	0.064 (4)	0.051 (3)	0.002 (2)	0.010 (2)	0.001 (3)
C13	0.054 (4)	0.105 (7)	0.077 (5)	0.010 (4)	0.031 (4)	−0.010 (5)
C14	0.042 (3)	0.042 (3)	0.040 (2)	−0.002 (2)	0.008 (2)	−0.006 (2)

Geometric parameters (Å, º)

Zn1—I1	2.5201 (11)	C7—C8	1.387 (7)
Zn1—I2	2.5517 (12)	C7—N2	1.430 (7)
Zn1—N1	2.059 (5)	C8—C10	1.384 (8)
Zn1—N2	2.104 (5)	C8—C9	1.502 (9)
C1—N1	1.326 (8)	C9—H9A	0.96
C1—C2	1.365 (10)	C9—H9B	0.96
C1—H1	0.93	C9—H9C	0.96
C2—C3	1.406 (13)	C10—C11	1.381 (10)
C2—H2	0.93	C10—H10	0.93
C3—C4	1.365 (11)	C11—C12	1.377 (10)
C3—H3	0.93	C11—H11	0.93
C4—C5	1.380 (8)	C12—C14	1.380 (9)
C4—H4	0.93	C12—C13	1.535 (11)
C5—N1	1.341 (8)	C13—H13A	0.96
C5—C6	1.457 (8)	C13—H13B	0.96
C6—N2	1.283 (7)	C13—H13C	0.96
C6—H6	0.93	C14—H14	0.93
C7—C14	1.382 (8)
I1—Zn1—I2	120.26 (4)	C14—C7—C8	122.2 (5)
N1—Zn1—N2	80.16 (19)	C14—C7—N2	119.3 (5)
N1—Zn1—I1	112.45 (14)	C8—C7—N2	118.5 (5)
N2—Zn1—I1	107.27 (13)	C10—C8—C7	117.3 (5)
N1—Zn1—I2	107.58 (15)	C10—C8—C9	119.8 (6)
N2—Zn1—I2	121.99 (13)	C7—C8—C9	122.9 (5)
C1—N1—C5	119.8 (6)	C8—C9—H9A	109.5
C1—N1—Zn1	127.7 (5)	C8—C9—H9B	109.5
C5—N1—Zn1	112.4 (4)	H9A—C9—H9B	109.5
C6—N2—C7	117.4 (5)	C8—C9—H9C	109.5
C6—N2—Zn1	111.5 (4)	H9A—C9—H9C	109.5
C7—N2—Zn1	129.6 (3)	H9B—C9—H9C	109.5
N1—C1—C2	121.7 (7)	C11—C10—C8	120.4 (6)
N1—C1—H1	119.2	C11—C10—H10	119.8
C2—C1—H1	119.2	C8—C10—H10	119.8
C1—C2—C3	118.3 (7)	C12—C11—C10	121.9 (6)
C1—C2—H2	120.8	C12—C11—H11	119
C3—C2—H2	120.8	C10—C11—H11	119
C4—C3—C2	120.2 (6)	C11—C12—C14	118.1 (6)
C4—C3—H3	119.9	C11—C12—C13	121.8 (7)
C2—C3—H3	119.9	C14—C12—C13	120.1 (7)
C3—C4—C5	117.4 (7)	C12—C13—H13A	109.5
C3—C4—H4	121.3	C12—C13—H13B	109.5
C5—C4—H4	121.3	H13A—C13—H13B	109.5
N1—C5—C4	122.5 (6)	C12—C13—H13C	109.5
N1—C5—C6	116.3 (5)	H13A—C13—H13C	109.5
C4—C5—C6	121.2 (6)	H13B—C13—H13C	109.5
N2—C6—C5	119.2 (5)	C12—C14—C7	120.0 (6)
N2—C6—H6	120.4	C12—C14—H14	120
C5—C6—H6	120.4	C7—C14—H14	120
N1—C1—C2—C3	−1.3 (11)	C4—C5—N1—C1	−0.7 (9)
C1—C2—C3—C4	1.4 (11)	C6—C5—N1—C1	179.5 (6)
C2—C3—C4—C5	−1.1 (10)	C4—C5—N1—Zn1	179.3 (5)
C3—C4—C5—N1	0.8 (10)	C6—C5—N1—Zn1	−0.5 (6)
C3—C4—C5—C6	−179.5 (6)	N2—Zn1—N1—C1	177.4 (6)
N1—C5—C6—N2	5.8 (8)	I1—Zn1—N1—C1	−77.9 (6)
C4—C5—C6—N2	−174.0 (6)	I2—Zn1—N1—C1	56.8 (6)
C14—C7—C8—C10	−0.2 (8)	N2—Zn1—N1—C5	−2.6 (4)
N2—C7—C8—C10	179.5 (5)	I1—Zn1—N1—C5	102.1 (4)
C14—C7—C8—C9	−178.4 (6)	I2—Zn1—N1—C5	−123.2 (4)
N2—C7—C8—C9	1.3 (8)	C5—C6—N2—C7	−174.8 (5)
C7—C8—C10—C11	−0.6 (8)	C5—C6—N2—Zn1	−7.7 (7)
C9—C8—C10—C11	177.6 (6)	C14—C7—N2—C6	62.5 (7)
C8—C10—C11—C12	0.3 (10)	C8—C7—N2—C6	−117.1 (6)
C10—C11—C12—C14	0.9 (10)	C14—C7—N2—Zn1	−101.8 (6)
C10—C11—C12—C13	−179.5 (7)	C8—C7—N2—Zn1	78.6 (6)
C11—C12—C14—C7	−1.7 (9)	N1—Zn1—N2—C6	5.6 (4)
C13—C12—C14—C7	178.7 (7)	I1—Zn1—N2—C6	−105.0 (4)
C8—C7—C14—C12	1.4 (9)	I2—Zn1—N2—C6	110.3 (4)
N2—C7—C14—C12	−178.3 (5)	N1—Zn1—N2—C7	170.6 (5)
C2—C1—N1—C5	0.9 (10)	I1—Zn1—N2—C7	60.0 (5)
C2—C1—N1—Zn1	−179.0 (5)	I2—Zn1—N2—C7	−84.7 (5)