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metal-organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 68| Part 2| February 2012| Page m134
doi:10.1107/S1600536811055577

A second monoclinic polymorph of {2,6-bis­[(2,4,5-tri­fluoro­phen­yl)imino­meth­yl]pyridine-κ3N,N′,N′′}di­chloridonickel(II)

Oscar Baldovino-Pantaleón,a Simón Hernández-Ortega,b* Reyna Reyes-Martínezb and David Morales-Moralesb

aUAM Reynosa Rodhe, Universidad Autónoma de Tamaulipas, Carr. Reynosa-San Fernando S/N, Reynosa, Tamaulipas 88779, Mexico, and bInstituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, México, DF, 04510, Mexico
*Correspondence e-mail: simonho@unam.mx

(Received 30 November 2011; accepted 24 December 2011; online 11 January 2012)

The asymmetric unit of the title compound, [NiCl2(C19H9F6N3)], contains one half-mol­ecule residing on a crystallographic twofold rotation axis. The title compound crystallizes in space group C2/c while the previously reported polymorph was reported in P21/c [Baldovino-Pantaleón et al. (2006[Baldovino-Pantaleón, O., Hernández-Ortega, S. & Morales-Morales, D. (2006). Adv. Synth. Catal. 348, 236-242.]). Adv. Synth. Catal. 348, 236–242]. The Ni2+ ion exhibits a penta­coordinate distorted trigonal–bipyramidal NiCl2N3 geometry, with two Cl atoms in the equatorial plane. In the crystal, mol­ecules are linked by inter­molecular C—F⋯π [F⋯centroid = 2.9676 (14) Å] inter­actions.

Related literature

For related studies, see: Baldovino-Pantaleón et al. (2005[Baldovino-Pantaleón, O., Hernández-Ortega, S. & Morales-Morales, D. (2005). Inorg. Chem. Commun. 8, 955-959.], 2006[Baldovino-Pantaleón, O., Hernández-Ortega, S. & Morales-Morales, D. (2006). Adv. Synth. Catal. 348, 236-242.]); Morales-Morales (2008[Morales-Morales, D. (2008). Mini-Rev. Org. Chem. 5, 141-152.]); Serrano-Becerra & Morales-Morales (2009[Serrano-Becerra, J. M. & Morales-Morales, D. (2009). Curr. Org. Synth. 6, 169-192.]). For catalysis reactions, see: Gómez-Benítez et al. (2006[Gómez-Benítez, V., Baldovino-Pantaleón, O., Herrera-Alvarez, C., Toscano, R. A. & Morales-Morales, D. (2006). Tetrahedron Lett. 47, 5059-5062.]). For the previously reported polymorph, see; Baldovino-Pantaleón et al. (2006[Baldovino-Pantaleón, O., Hernández-Ortega, S. & Morales-Morales, D. (2006). Adv. Synth. Catal. 348, 236-242.]).

[Scheme 1]

Experimental

Crystal data

  • [NiCl2(C19H9F6N3)]

  • Mr = 522.90

  • Monoclinic, C 2/c

  • a = 18.0947 (13) Å

  • b = 8.8967 (6) Å

  • c = 12.1638 (9) Å

  • β = 101.421 (2)°

  • V = 1919.4 (2) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 1.36 mm−1

  • T = 298 K

  • 0.32 × 0.16 × 0.06 mm
Data collection

  • Bruker SMART APEX CCD area-detector diffractometer

  • Absorption correction: analytical (SHELXTL; Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) Tmin = 0.740, Tmax = 0.921

  • 7821 measured reflections

  • 1751 independent reflections

  • 1482 reflections with I > 2σ(I)

  • Rint = 0.033
Refinement

  • R[F2 > 2σ(F2)] = 0.025

  • wR(F2) = 0.058

  • S = 0.96

  • 1751 reflections

  • 142 parameters

  • H-atom parameters constrained

  • Δρmax = 0.23 e Å−3

  • Δρmin = −0.20 e Å−3

Data collection: SMART (Bruker, 2007[Bruker (2007). SAINT and SMART. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). SAINT and SMART. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811055577/fj2491sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811055577/fj2491Isup2.hkl

checkCIF report


Comment top

For the last decade our research group has focused on the design, synthesis and use of pincer-type ligands and their transition metal complexes for novel organic transformations (Morales-Morales 2008; Serrano-Becerra & Morales-Morales, 2009). The selection of these ligands has been done on the basis of the robustness that they confer to the transition metal complexes they form (Baldovino-Pantaleón, et al., 2005, 2006). In recent years this kind of complexes have gained more interest particularly those derived from Ni, due to the importance that cross-coupling reactions have gained in important organic transformations of potential industrial relevance and the potential application of the nickel derivatives for the same sort of process regularly catalized by analogous palladium derivatives, but using a far more cheaper metal (Gómez-Benítez et al., 2006). The title compound is a polymorphous of a compound described previously (Baldovino-Pantaleón, et al., 2006).

The molecular structure of I is shown in figure 1 with the numbering scheme. In comparison, compound II described previously (Baldovino-Pantaleón, et al., 2006), was crystallized in a monoclinic (P 21/c), while compound I, crystallizes in space group C 2/c. The asymmetric unit consists of a half molecule with Ni—N1—C4—H4 in a special position (1/2, y, 1/4), and by two fold axis the complete molecule is generated. The Ni atom is found in a pentacoordinated distorted bipyramidal geometry with the two chlorides occupying the equatorial positions. While the fragment N1—Ni—N2—N2A is planar, the pyridine ring is slightly rotated by 5.4 (1)°. The 2,4,5-trifluorophenyl ring is not coplanar and is forming a dihedral angle of 39.41 (5)° with the coordination metallic center, while in II, the fluorophenyl rings have dihedral angles of 14.4 (2)° and 13.4 (2)° with the coordination metallic center. The bond distances Ni—N(imino) in I are slightly shorter than in II. In absence of clasic aceptor-donor H atom, the weak interactions become very important stabilizing the crystal structure. The molecules in the crystal structure are linked by C—H—F—C, C—H—π, C—F—π and C—F—F—C intermolecular interactions (Table 1).

Related literature top

For related studies, see Baldovino-Pantaleón et al. (2005, 2006); Morales-Morales (2008); Serrano-Becerra & Morales-Morales (2009). For catalysis reactions, see; Gómez-Benítez et al. (2006). For the previously reported polymorph, see; Baldovino-Pantaleón et al. (2006).

Experimental top

A solution of the ligand {C5H3N-2,6-(CH=N—C6H2-2,4,5-F3)2} (120 mg, 0.33 mmol) in anhydrous CH2Cl2 (10 ml) was added to a stirred solution of NiCl2.6 H2O(0.078 g, 0.33 mmol) in absolute methanol (10 ml). The resulting green solution was stirred at room temperature for 2 h. After this time a red suspension is noted and the solvent evaporated under vacuum. The product was purified by recrystallization from MeOH; the resulting precipitated was filtered and washed with hexane (3 X 5 ml) and dried under vacuum. Crystals suitable for single-crystal X-ray diffraction studies were obtained from a dichloromethane/ methanol (4:1) solution. A red solid was obtained; yield: 142 mg (88%); mp: 240°C

Refinement top

H atoms were included in calculated positions (C—H = 0.93 Å), and refined using a riding model,with Uiso(H) = 1.2Ueq of the carrier atom.

Computing details top

Data collection: SMART (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of I with the numbering scheme. Displacement ellipsoids are shown at the 40% probability level. H atoms have been omitted for clarity.
{2,6-Bis[(2,4,5-trifluorophenyl)iminomethyl]pyridine- κ3N,N',N''}dichloridonickel(II) top
Crystal data top
[NiCl2(C19H9F6N3)]F(000) = 1040
Mr = 522.90Dx = 1.810 Mg m−3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 5009 reflections
a = 18.0947 (13) Åθ = 2.6–32.1°
b = 8.8967 (6) ŵ = 1.36 mm−1
c = 12.1638 (9) ÅT = 298 K
β = 101.421 (2)°Prism, red
V = 1919.4 (2) Å30.32 × 0.16 × 0.06 mm
Z = 4
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer		1751 independent reflections
Radiation source: fine-focus sealed tube1482 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.033
Detector resolution: 0.83 pixels mm-1θmax = 25.3°, θmin = 2.3°
ω scansh = −21→21
Absorption correction: analytical
(SHELXTL; Sheldrick, 2008)		k = −10→10
Tmin = 0.740, Tmax = 0.921l = −14→14
7821 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)] = 0.025Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.058H-atom parameters constrained
S = 0.96 w = 1/[σ2(Fo2) + (0.034P)2]
where P = (Fo2 + 2Fc2)/3
1751 reflections(Δ/σ)max < 0.001
142 parametersΔρmax = 0.23 e Å−3
0 restraintsΔρmin = −0.20 e Å−3
Crystal data top
[NiCl2(C19H9F6N3)]V = 1919.4 (2) Å3
Mr = 522.90Z = 4
Monoclinic, C2/cMo Kα radiation
a = 18.0947 (13) ŵ = 1.36 mm−1
b = 8.8967 (6) ÅT = 298 K
c = 12.1638 (9) Å0.32 × 0.16 × 0.06 mm
β = 101.421 (2)°
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer		1751 independent reflections
Absorption correction: analytical
(SHELXTL; Sheldrick, 2008)		1482 reflections with I > 2σ(I)
Tmin = 0.740, Tmax = 0.921Rint = 0.033
7821 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0250 restraints
wR(F2) = 0.058H-atom parameters constrained
S = 0.96Δρmax = 0.23 e Å−3
1751 reflectionsΔρmin = −0.20 e Å−3
142 parameters
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
Ni10.50000.68998 (3)0.25000.03615 (12)
Cl10.42526 (3)0.79023 (6)0.35781 (4)0.06007 (17)
F10.62550 (7)0.60471 (13)0.63576 (9)0.0642 (3)
F20.75608 (7)1.06173 (13)0.66763 (10)0.0688 (4)
F30.72148 (8)1.09768 (14)0.44569 (11)0.0767 (4)
N10.50000.4707 (2)0.25000.0352 (5)
N20.58620 (8)0.63599 (16)0.39784 (11)0.0372 (3)
C20.54313 (10)0.39674 (18)0.33462 (14)0.0384 (4)
C30.54303 (12)0.2412 (2)0.33833 (16)0.0505 (5)
H30.57140.19020.39910.061*
C40.50000.1634 (3)0.25000.0586 (8)
H40.50000.05880.25000.070*
C50.58923 (10)0.4948 (2)0.41731 (13)0.0399 (4)
H50.61960.45590.48170.048*
C60.63018 (9)0.7410 (2)0.47162 (14)0.0376 (4)
C70.64917 (10)0.7265 (2)0.58667 (15)0.0428 (4)
C80.69027 (11)0.8327 (2)0.65465 (16)0.0513 (5)
H80.70150.82070.73210.062*
C90.71419 (10)0.9570 (2)0.60497 (16)0.0478 (5)
C100.69631 (11)0.9745 (2)0.49109 (16)0.0483 (5)
C110.65417 (10)0.8698 (2)0.42393 (15)0.0461 (5)
H110.64160.88470.34680.055*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Ni10.0457 (2)0.02916 (18)0.03209 (19)0.0000.00412 (14)0.000
Cl10.0713 (4)0.0718 (4)0.0386 (3)0.0258 (3)0.0145 (2)0.0021 (2)
F10.0917 (9)0.0633 (8)0.0368 (6)−0.0145 (7)0.0106 (6)0.0031 (5)
F20.0692 (8)0.0631 (8)0.0648 (8)−0.0106 (6)−0.0090 (6)−0.0235 (6)
F30.0997 (10)0.0570 (8)0.0663 (8)−0.0309 (7)−0.0009 (7)0.0030 (6)
N10.0434 (12)0.0312 (10)0.0307 (10)0.0000.0065 (9)0.000
N20.0413 (8)0.0373 (8)0.0316 (8)0.0031 (7)0.0036 (6)−0.0016 (6)
C20.0476 (10)0.0339 (10)0.0336 (9)0.0044 (8)0.0077 (8)0.0027 (7)
C30.0710 (14)0.0346 (10)0.0429 (11)0.0078 (10)0.0041 (10)0.0056 (8)
C40.088 (2)0.0300 (14)0.0558 (18)0.0000.0083 (16)0.000
C50.0465 (10)0.0387 (10)0.0320 (9)0.0088 (8)0.0013 (8)0.0018 (8)
C60.0361 (10)0.0380 (9)0.0360 (9)0.0060 (8)0.0004 (8)−0.0033 (8)
C70.0464 (11)0.0434 (11)0.0372 (10)0.0040 (8)0.0051 (8)−0.0018 (8)
C80.0555 (12)0.0616 (13)0.0332 (10)0.0073 (10)−0.0002 (9)−0.0080 (9)
C90.0424 (11)0.0463 (12)0.0501 (11)0.0038 (9)−0.0017 (9)−0.0147 (9)
C100.0491 (11)0.0427 (11)0.0499 (12)−0.0027 (9)0.0022 (9)−0.0009 (9)
C110.0517 (11)0.0448 (11)0.0372 (10)0.0001 (9)−0.0018 (8)0.0006 (8)
Geometric parameters (Å, º) top
Ni1—N11.9508 (19)C3—C41.382 (2)
Ni1—N2i2.1878 (13)C3—H30.9300
Ni1—N22.1878 (13)C4—C3i1.382 (2)
Ni1—Cl1i2.2464 (5)C4—H40.9300
Ni1—Cl12.2464 (5)C5—H50.9300
F1—C71.347 (2)C6—C71.379 (2)
F2—C91.3400 (19)C6—C111.393 (3)
F3—C101.347 (2)C7—C81.374 (3)
N1—C2i1.3354 (18)C8—C91.370 (3)
N1—C21.3354 (18)C8—H80.9300
N2—C51.277 (2)C9—C101.368 (3)
N2—C61.424 (2)C10—C111.367 (3)
C2—C31.384 (3)C11—H110.9300
C2—C51.462 (2)
N1—Ni1—N2i77.32 (4)C3—C4—H4120.1
N1—Ni1—N277.32 (4)C3i—C4—H4120.1
N2i—Ni1—N2154.64 (8)N2—C5—C2117.50 (15)
N1—Ni1—Cl1i113.393 (16)N2—C5—H5121.2
N2i—Ni1—Cl1i91.20 (4)C2—C5—H5121.2
N2—Ni1—Cl1i98.82 (4)C7—C6—C11117.64 (16)
N1—Ni1—Cl1113.393 (16)C7—C6—N2125.03 (17)
N2i—Ni1—Cl198.82 (4)C11—C6—N2117.31 (16)
N2—Ni1—Cl191.20 (4)F1—C7—C8117.93 (17)
Cl1i—Ni1—Cl1133.21 (3)F1—C7—C6119.18 (16)
C2i—N1—C2121.0 (2)C8—C7—C6122.88 (18)
C2i—N1—Ni1119.52 (10)C9—C8—C7118.05 (18)
C2—N1—Ni1119.52 (10)C9—C8—H8121.0
C5—N2—C6122.00 (15)C7—C8—H8121.0
C5—N2—Ni1111.45 (11)F2—C9—C10119.38 (18)
C6—N2—Ni1126.33 (11)F2—C9—C8120.18 (18)
N1—C2—C3120.88 (17)C10—C9—C8120.44 (17)
N1—C2—C5113.77 (15)F3—C10—C11120.20 (17)
C3—C2—C5125.34 (16)F3—C10—C9118.48 (16)
C4—C3—C2118.68 (18)C11—C10—C9121.32 (18)
C4—C3—H3120.7C10—C11—C6119.65 (17)
C2—C3—H3120.7C10—C11—H11120.2
C3—C4—C3i119.8 (3)C6—C11—H11120.2
N2i—Ni1—N1—C2i4.58 (9)Ni1—N2—C5—C26.53 (19)
N2—Ni1—N1—C2i−175.42 (9)N1—C2—C5—N2−3.1 (2)
Cl1i—Ni1—N1—C2i−81.18 (9)C3—C2—C5—N2175.64 (17)
Cl1—Ni1—N1—C2i98.82 (9)C5—N2—C6—C7−33.8 (3)
N2i—Ni1—N1—C2−175.42 (9)Ni1—N2—C6—C7140.38 (15)
N2—Ni1—N1—C24.58 (9)C5—N2—C6—C11147.89 (17)
Cl1i—Ni1—N1—C298.82 (9)Ni1—N2—C6—C11−37.9 (2)
Cl1—Ni1—N1—C2−81.18 (9)C11—C6—C7—F1178.61 (16)
N1—Ni1—N2—C5−6.01 (11)N2—C6—C7—F10.3 (3)
N2i—Ni1—N2—C5−6.01 (11)C11—C6—C7—C8−0.1 (3)
Cl1i—Ni1—N2—C5−118.15 (11)N2—C6—C7—C8−178.39 (17)
Cl1—Ni1—N2—C5107.72 (12)F1—C7—C8—C9−179.78 (17)
N1—Ni1—N2—C6179.28 (14)C6—C7—C8—C9−1.1 (3)
N2i—Ni1—N2—C6179.28 (14)C7—C8—C9—F2−178.30 (16)
Cl1i—Ni1—N2—C667.14 (13)C7—C8—C9—C101.0 (3)
Cl1—Ni1—N2—C6−66.99 (13)F2—C9—C10—F3−0.2 (3)
C2i—N1—C2—C3−1.51 (13)C8—C9—C10—F3−179.49 (18)
Ni1—N1—C2—C3178.49 (13)F2—C9—C10—C11179.53 (17)
C2i—N1—C2—C5177.34 (16)C8—C9—C10—C110.2 (3)
Ni1—N1—C2—C5−2.66 (16)F3—C10—C11—C6178.29 (17)
N1—C2—C3—C43.0 (2)C9—C10—C11—C6−1.4 (3)
C5—C2—C3—C4−175.74 (15)C7—C6—C11—C101.3 (3)
C2—C3—C4—C3i−1.44 (12)N2—C6—C11—C10179.76 (16)
C6—N2—C5—C2−178.49 (15)
Symmetry code: (i) −x+1, y, −z+1/2.

Experimental details

Crystal data
Chemical formula[NiCl2(C19H9F6N3)]
Mr522.90
Crystal system, space groupMonoclinic, C2/c
Temperature (K)298
a, b, c (Å)18.0947 (13), 8.8967 (6), 12.1638 (9)
β (°) 101.421 (2)
V (Å3)1919.4 (2)
Z4
Radiation typeMo Kα
µ (mm−1)1.36
Crystal size (mm)0.32 × 0.16 × 0.06
Data collection
DiffractometerBruker SMART APEX CCD area-detector
diffractometer
Absorption correctionAnalytical
(SHELXTL; Sheldrick, 2008)
Tmin, Tmax0.740, 0.921
No. of measured, independent and
observed [I > 2σ(I)] reflections		7821, 1751, 1482
Rint0.033
(sin θ/λ)max (Å−1)0.602
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.025, 0.058, 0.96
No. of reflections1751
No. of parameters142
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.23, −0.20

Computer programs: SMART (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Table 1. Intermolecular and intramolecular interaction C-F–π, C-H–π, π–π of (I) (Å) top
H/F/centroidcentroid/FdistanceSymmetry-code
H8F32.652(i)
H8F22.648(ii)
F1F22.903(iii)
F1N1-C42.968(iv)
(i) x, 2-y, 1.5 +z; (ii) -x+1.5, +y-1/2', -z+1.5; (iii) -x+1.5, 1.5+y, -z+1.5; (iv) x, -y+1, z-1/2
 

Acknowledgements

RRM would like to thank CONACYT for a postdoctoral scholarship (agreement 290586-UNAM). Support of this research by CONACYT (154732), PAPIIT (IN201711) and the Fondo Mixto de Fomento a la Investigación Científica y Tecnológica CONACyT - Gobierno del Estado de Tamaulipas is gratefully acknowledged.

References

First citationBaldovino-Pantaleón, O., Hernández-Ortega, S. & Morales-Morales, D. (2005). Inorg. Chem. Commun. 8, 955–959.  Web of Science CSD CrossRef CAS Google Scholar
 First citationBaldovino-Pantaleón, O., Hernández-Ortega, S. & Morales-Morales, D. (2006). Adv. Synth. Catal. 348, 236–242.  Web of Science CSD CrossRef CAS Google Scholar
 First citationBruker (2007). SAINT and SMART. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
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ISSN: 2056-9890
Volume 68| Part 2| February 2012| Page m134
doi:10.1107/S1600536811055577
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