Dichlorido[2-(phenyl­imino­meth­yl)quinoline-N,N′]palladium(II)

Motswainyana, W.M.; Onani, M.O.; Madiehe, A.M.

doi:10.1107/S1600536812009130

metal-organic compounds

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ISSN: 2056-9890

Volume 68| Part 4| April 2012| Page m380

doi:10.1107/S1600536812009130

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Dichlorido[2-(phenyliminomethyl)quinoline-N,N′]palladium(II)

William M. Motswainyana,^a Martin O. Onani ^a ^* and Abram M. Madiehe ^b

^aDepartment of Chemistry, University of the Western Cape, Private Bag X17, Bellville, 7535, South Africa, and ^bDepartment of Biotechnology, University of the Western Cape, Private Bag X17, Bellville, 7535, South Africa
^*Correspondence e-mail: monani@uwc.ac.za

(Received 17 February 2012; accepted 29 February 2012; online 7 March 2012)

In the title complex, [PdCl₂(C₁₆H₁₂N₂)], the Pd^II ion is coordinated by two N atoms [Pd—N 2.039 (2), 2.073 (2) Å] from a bidentate ligand and two chloride anions [Pd—Cl 2.2655 (7), 2.2991 (7) Å] in a distorted square-planar geometry. In the crystal, π–π interactions between the six-membered rings of the quinoline fragments [centroid–centroid distances = 3.815 (5), 3.824 (5) Å] link two molecules into centrosymmetric dimers.

Related literature

For the synthesis of quinolyl-imine ligands and their transition metal-based complexes, see: Ardizzoia et al. (2009 ); Tianpengfei et al. (2011 ); Wei et al. (2009 ). For related structures, see: Motswainyana et al. (2011 ); Onani & Motswainyana (2011 ); Massa & Dehghampour (2009 ); Keter et al. (2008 ); Singh et al. (2007 ); Doherty et al. (2002 ).

Experimental

Crystal data

[PdCl₂(C₁₆H₁₂N₂)]
M_r = 409.58
Monoclinic, P 2₁ /c
a = 10.0980 (4) Å
b = 15.8936 (6) Å
c = 10.0010 (3) Å
β = 112.005 (2)°
V = 1488.17 (9) Å³
Z = 4
Mo Kα radiation
μ = 1.60 mm⁻¹
T = 173 K
0.23 × 0.16 × 0.03 mm

Data collection

Bruker SMART APEX CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ) T_min = 0.710, T_max = 0.954
49839 measured reflections
3400 independent reflections
2575 reflections with I > 2σ(I)
R_int = 0.086

Refinement

R[F² > 2σ(F²)] = 0.030
wR(F²) = 0.063
S = 1.05
3400 reflections
190 parameters
H-atom parameters constrained
Δρ_max = 1.00 e Å⁻³
Δρ_min = −0.59 e Å⁻³

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812009130/cv5251sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812009130/cv5251Isup2.hkl

checkCIF report

Comment top

The transition metal-diimine ligands are well known and have been used extensively as catalyst stabilisers in many reported catalytic processes (Motswainyana et al., 2011; Massa et al., 2009; Tiangpengfei et al., 2011; Ardizzoia et al., 2009). Several of these complexes, besides being heavily utilized in the catalytic field, equally double up as therapeutic agents (Keter et al., 2008; Singh et al., 2007).

The asymmetric unit of the title compound is shown in Fig. 1. In the title compound, the Pd^II ion is bidentately coordinated to two N atoms of the 2-quinolylbenzylimine ligand and two chloride anions. The complex forms a distorted square planar geometry around the central metal. It is notable that the bond length of the Pd—Cl bond trans to the quinolyl-N atom are similar indicating lack of trans influence. There are two π-π interations between the quinoline ring systems as indicated by the interplanar centroid-centroid distances of 3.815 (5) and 3.824 (5) linking two molecules into a centrosymmetric dimers.

Related literature top

For the synthesis of quinolyl-imine ligands and their transition metal-based complexes, see: Ardizzoia et al. (2009); Tianpengfei et al. (2011); Wei et al. (2009). For related structures, see: Motswainyana et al. (2011); Onani & Motswainyana (2011); Massa & Dehghampour (2009); Keter et al. (2008); Singh et al. (2007); Doherty et al. (2002).

Experimental top

To a suspension of PdCl₂(cod) (0.0925 g, 0.324 mmol) in CH₂Cl₂ (5 ml) was added a solution of (2-quinolylbenzyl)imine (0.0748 g, 0.322 mmol) in CH₂Cl₂ (10 ml). The yellow solution was stirred under reflux for 4 h, resulting in the formation of yellow precipitate. The precipitate was filtered to obtain a pure yellow solid. Recrystallization from a mixture of a minimum of CH₂Cl₂ and an excess of C₆H₁₄ solution gave single crystals suitable for X-ray diffraction studies. The product yield was 82%.

Structure description top

For the synthesis of quinolyl-imine ligands and their transition metal-based complexes, see: Ardizzoia et al. (2009); Tianpengfei et al. (2011); Wei et al. (2009). For related structures, see: Motswainyana et al. (2011); Onani & Motswainyana (2011); Massa & Dehghampour (2009); Keter et al. (2008); Singh et al. (2007); Doherty et al. (2002).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

Fig. 1. Molecular structure of the title compound showing the atomic numbering and 35% probabilty displacement ellipsoids.

Dichlorido[2-(phenyliminomethyl)quinoline-N,N']palladium(II) top

Crystal data top

[PdCl₂(C₁₆H₁₂N₂)]	F(000) = 808
M_r = 409.58	D_x = 1.828 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 49839 reflections
a = 10.0980 (4) Å	θ = 3.4–27.5°
b = 15.8936 (6) Å	µ = 1.60 mm⁻¹
c = 10.0010 (3) Å	T = 173 K
β = 112.005 (2)°	Plate, orange
V = 1488.17 (9) Å³	0.23 × 0.16 × 0.03 mm
Z = 4

Data collection top

Bruker SMART APEX CCD diffractometer	3400 independent reflections
Radiation source: fine-focus sealed tube	2575 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.086
1.0° φ scans and ω scans	θ_max = 27.5°, θ_min = 3.4°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −13→13
T_min = 0.710, T_max = 0.954	k = −20→20
49839 measured reflections	l = −12→12

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.030	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.063	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.0267P)² + 0.1302P] where P = (F_o² + 2F_c²)/3
3400 reflections	(Δ/σ)_max = 0.001
190 parameters	Δρ_max = 1.00 e Å⁻³
0 restraints	Δρ_min = −0.59 e Å⁻³

Crystal data top

[PdCl₂(C₁₆H₁₂N₂)]	V = 1488.17 (9) Å³
M_r = 409.58	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 10.0980 (4) Å	µ = 1.60 mm⁻¹
b = 15.8936 (6) Å	T = 173 K
c = 10.0010 (3) Å	0.23 × 0.16 × 0.03 mm
β = 112.005 (2)°

Data collection top

Bruker SMART APEX CCD diffractometer	3400 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	2575 reflections with I > 2σ(I)
T_min = 0.710, T_max = 0.954	R_int = 0.086
49839 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.030	0 restraints
wR(F²) = 0.063	H-atom parameters constrained
S = 1.05	Δρ_max = 1.00 e Å⁻³
3400 reflections	Δρ_min = −0.59 e Å⁻³
190 parameters

Special details top

Experimental. 'crystal mounted on a cryoloop'

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

	x	y	z	U_iso*/U_eq
Pd1	0.69195 (2)	0.038621 (12)	0.43401 (2)	0.02445 (9)
Cl1	0.65380 (7)	0.18083 (4)	0.39731 (8)	0.03194 (18)
Cl2	0.89245 (7)	0.06851 (4)	0.62746 (8)	0.03355 (18)
N1	0.5127 (2)	−0.00321 (13)	0.2642 (2)	0.0243 (5)
N2	0.6938 (2)	−0.08478 (13)	0.4906 (2)	0.0264 (5)
C1	0.4308 (3)	0.03303 (15)	0.1353 (3)	0.0268 (6)
C2	0.4815 (3)	0.10349 (15)	0.0822 (3)	0.0289 (6)
H2	0.5729	0.1264	0.1359	0.035*
C3	0.3981 (3)	0.13838 (16)	−0.0468 (3)	0.0333 (7)
H3	0.4329	0.1855	−0.0823	0.040*
C4	0.2618 (3)	0.10609 (17)	−0.1284 (3)	0.0387 (7)
H4	0.2045	0.1326	−0.2162	0.046*
C5	0.2123 (3)	0.03718 (18)	−0.0818 (3)	0.0374 (8)
H5	0.1211	0.0150	−0.1384	0.045*
C6	0.2947 (3)	−0.00179 (17)	0.0495 (3)	0.0295 (7)
C7	0.2488 (3)	−0.07536 (17)	0.0973 (3)	0.0338 (7)
H7	0.1566	−0.0977	0.0446	0.041*
C8	0.3373 (3)	−0.11471 (16)	0.2201 (3)	0.0307 (7)
H8	0.3102	−0.1663	0.2506	0.037*
C9	0.4687 (3)	−0.07709 (16)	0.2995 (3)	0.0270 (6)
C10	0.5726 (3)	−0.11936 (16)	0.4231 (3)	0.0269 (6)
H10	0.5507	−0.1724	0.4536	0.032*
C11	0.7958 (3)	−0.12731 (15)	0.6125 (3)	0.0251 (6)
C12	0.7546 (3)	−0.16047 (15)	0.7185 (3)	0.0277 (6)
H12	0.6589	−0.1544	0.7122	0.033*
C13	0.8534 (3)	−0.20272 (16)	0.8341 (3)	0.0327 (7)
H13	0.8264	−0.2240	0.9090	0.039*
C14	0.9911 (3)	−0.21379 (16)	0.8403 (3)	0.0361 (7)
H14	1.0581	−0.2444	0.9178	0.043*
C15	1.0315 (3)	−0.18044 (17)	0.7341 (3)	0.0368 (7)
H15	1.1266	−0.1882	0.7391	0.044*
C16	0.9356 (3)	−0.13606 (16)	0.6209 (3)	0.0313 (7)
H16	0.9647	−0.1117	0.5494	0.038*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Pd1	0.02349 (14)	0.02256 (14)	0.02361 (14)	−0.00179 (8)	0.00458 (10)	0.00024 (9)
Cl1	0.0326 (4)	0.0229 (3)	0.0349 (4)	−0.0023 (3)	0.0063 (3)	−0.0004 (3)
Cl2	0.0274 (4)	0.0340 (4)	0.0309 (4)	−0.0049 (3)	0.0014 (3)	−0.0011 (3)
N1	0.0253 (12)	0.0223 (12)	0.0220 (13)	−0.0001 (10)	0.0051 (10)	−0.0013 (10)
N2	0.0252 (13)	0.0244 (12)	0.0275 (13)	0.0008 (10)	0.0075 (11)	0.0050 (11)
C1	0.0287 (16)	0.0281 (15)	0.0206 (15)	0.0077 (12)	0.0057 (12)	−0.0020 (12)
C2	0.0332 (16)	0.0247 (15)	0.0274 (16)	0.0014 (12)	0.0098 (13)	−0.0038 (13)
C3	0.0464 (18)	0.0257 (15)	0.0267 (17)	0.0063 (13)	0.0125 (15)	−0.0004 (13)
C4	0.0468 (19)	0.0346 (17)	0.0262 (17)	0.0126 (14)	0.0039 (15)	0.0037 (14)
C5	0.0313 (17)	0.0417 (19)	0.0287 (18)	0.0085 (13)	−0.0008 (14)	−0.0035 (14)
C6	0.0290 (16)	0.0280 (16)	0.0267 (17)	0.0046 (12)	0.0049 (13)	−0.0055 (13)
C7	0.0272 (16)	0.0365 (17)	0.0314 (18)	−0.0032 (13)	0.0037 (14)	−0.0089 (14)
C8	0.0325 (16)	0.0267 (15)	0.0311 (17)	−0.0062 (12)	0.0098 (14)	−0.0066 (13)
C9	0.0298 (16)	0.0273 (15)	0.0232 (16)	0.0008 (12)	0.0092 (13)	−0.0032 (12)
C10	0.0320 (16)	0.0222 (14)	0.0260 (16)	−0.0007 (12)	0.0105 (13)	0.0006 (12)
C11	0.0276 (15)	0.0183 (13)	0.0250 (16)	0.0004 (11)	0.0048 (13)	−0.0029 (12)
C12	0.0273 (15)	0.0244 (14)	0.0303 (17)	−0.0005 (12)	0.0093 (13)	−0.0030 (13)
C13	0.0423 (18)	0.0248 (15)	0.0266 (17)	0.0021 (13)	0.0078 (14)	0.0043 (13)
C14	0.0371 (18)	0.0234 (15)	0.0330 (19)	0.0044 (13)	−0.0039 (14)	−0.0020 (13)
C15	0.0273 (16)	0.0316 (16)	0.045 (2)	0.0008 (13)	0.0059 (15)	−0.0090 (15)
C16	0.0343 (17)	0.0280 (15)	0.0309 (18)	0.0016 (13)	0.0114 (14)	−0.0025 (13)

Geometric parameters (Å, º) top

Pd1—N2	2.039 (2)	C6—C7	1.406 (4)
Pd1—N1	2.073 (2)	C7—C8	1.370 (4)
Pd1—Cl2	2.2655 (7)	C7—H7	0.9500
Pd1—Cl1	2.2991 (7)	C8—C9	1.400 (4)
N1—C9	1.348 (3)	C8—H8	0.9500
N1—C1	1.371 (3)	C9—C10	1.452 (4)
N2—C10	1.279 (3)	C10—H10	0.9500
N2—C11	1.436 (3)	C11—C12	1.380 (4)
C1—C2	1.415 (3)	C11—C16	1.390 (4)
C1—C6	1.431 (4)	C12—C13	1.385 (4)
C2—C3	1.366 (4)	C12—H12	0.9500
C2—H2	0.9500	C13—C14	1.380 (4)
C3—C4	1.407 (4)	C13—H13	0.9500
C3—H3	0.9500	C14—C15	1.379 (4)
C4—C5	1.357 (4)	C14—H14	0.9500
C4—H4	0.9500	C15—C16	1.377 (4)
C5—C6	1.407 (4)	C15—H15	0.9500
C5—H5	0.9500	C16—H16	0.9500

N2—Pd1—N1	80.41 (8)	C8—C7—C6	119.8 (3)
N2—Pd1—Cl2	93.00 (6)	C8—C7—H7	120.1
N1—Pd1—Cl2	173.36 (6)	C6—C7—H7	120.1
N2—Pd1—Cl1	166.73 (6)	C7—C8—C9	118.4 (3)
N1—Pd1—Cl1	98.16 (6)	C7—C8—H8	120.8
Cl2—Pd1—Cl1	88.45 (3)	C9—C8—H8	120.8
C9—N1—C1	118.1 (2)	N1—C9—C8	124.0 (2)
C9—N1—Pd1	109.69 (16)	N1—C9—C10	115.0 (2)
C1—N1—Pd1	132.02 (17)	C8—C9—C10	120.9 (2)
C10—N2—C11	119.0 (2)	N2—C10—C9	119.6 (2)
C10—N2—Pd1	111.05 (17)	N2—C10—H10	120.2
C11—N2—Pd1	128.13 (16)	C9—C10—H10	120.2
N1—C1—C2	120.7 (2)	C12—C11—C16	120.5 (2)
N1—C1—C6	120.5 (2)	C12—C11—N2	120.4 (2)
C2—C1—C6	118.8 (2)	C16—C11—N2	119.2 (2)
C3—C2—C1	119.6 (3)	C11—C12—C13	119.8 (2)
C3—C2—H2	120.2	C11—C12—H12	120.1
C1—C2—H2	120.2	C13—C12—H12	120.1
C2—C3—C4	121.4 (3)	C14—C13—C12	119.9 (3)
C2—C3—H3	119.3	C14—C13—H13	120.1
C4—C3—H3	119.3	C12—C13—H13	120.1
C5—C4—C3	120.1 (3)	C15—C14—C13	120.0 (3)
C5—C4—H4	120.0	C15—C14—H14	120.0
C3—C4—H4	120.0	C13—C14—H14	120.0
C4—C5—C6	120.7 (3)	C16—C15—C14	120.7 (3)
C4—C5—H5	119.7	C16—C15—H15	119.6
C6—C5—H5	119.7	C14—C15—H15	119.6
C7—C6—C5	121.9 (2)	C15—C16—C11	119.1 (3)
C7—C6—C1	118.9 (2)	C15—C16—H16	120.5
C5—C6—C1	119.3 (3)	C11—C16—H16	120.5

N2—Pd1—N1—C9	17.70 (17)	C2—C1—C6—C5	−3.0 (4)
Cl2—Pd1—N1—C9	24.5 (6)	C5—C6—C7—C8	174.9 (3)
Cl1—Pd1—N1—C9	−148.95 (16)	C1—C6—C7—C8	−3.5 (4)
N2—Pd1—N1—C1	−168.0 (2)	C6—C7—C8—C9	3.9 (4)
Cl2—Pd1—N1—C1	−161.1 (4)	C1—N1—C9—C8	−7.0 (4)
Cl1—Pd1—N1—C1	25.4 (2)	Pd1—N1—C9—C8	168.3 (2)
N1—Pd1—N2—C10	−17.17 (18)	C1—N1—C9—C10	169.1 (2)
Cl2—Pd1—N2—C10	163.62 (18)	Pd1—N1—C9—C10	−15.7 (3)
Cl1—Pd1—N2—C10	67.7 (4)	C7—C8—C9—N1	1.5 (4)
N1—Pd1—N2—C11	178.4 (2)	C7—C8—C9—C10	−174.4 (2)
Cl2—Pd1—N2—C11	−0.8 (2)	C11—N2—C10—C9	−179.8 (2)
Cl1—Pd1—N2—C11	−96.8 (3)	Pd1—N2—C10—C9	14.1 (3)
C9—N1—C1—C2	−170.4 (2)	N1—C9—C10—N2	1.4 (4)
Pd1—N1—C1—C2	15.6 (4)	C8—C9—C10—N2	177.6 (2)
C9—N1—C1—C6	7.1 (4)	C10—N2—C11—C12	−47.7 (3)
Pd1—N1—C1—C6	−166.84 (18)	Pd1—N2—C11—C12	115.7 (2)
N1—C1—C2—C3	179.8 (2)	C10—N2—C11—C16	131.1 (3)
C6—C1—C2—C3	2.2 (4)	Pd1—N2—C11—C16	−65.5 (3)
C1—C2—C3—C4	0.4 (4)	C16—C11—C12—C13	0.0 (4)
C2—C3—C4—C5	−2.2 (4)	N2—C11—C12—C13	178.8 (2)
C3—C4—C5—C6	1.3 (4)	C11—C12—C13—C14	−2.1 (4)
C4—C5—C6—C7	−177.2 (3)	C12—C13—C14—C15	2.2 (4)
C4—C5—C6—C1	1.3 (4)	C13—C14—C15—C16	−0.1 (4)
N1—C1—C6—C7	−2.1 (4)	C14—C15—C16—C11	−1.9 (4)
C2—C1—C6—C7	175.5 (2)	C12—C11—C16—C15	1.9 (4)
N1—C1—C6—C5	179.4 (2)	N2—C11—C16—C15	−176.8 (2)

Experimental details

Crystal data
Chemical formula	[PdCl₂(C₁₆H₁₂N₂)]
M_r	409.58
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	173
a, b, c (Å)	10.0980 (4), 15.8936 (6), 10.0010 (3)
β (°)	112.005 (2)
V (Å³)	1488.17 (9)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	1.60
Crystal size (mm)	0.23 × 0.16 × 0.03

Data collection
Diffractometer	Bruker SMART APEX CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.710, 0.954
No. of measured, independent and observed [I > 2σ(I)] reflections	49839, 3400, 2575
R_int	0.086
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.030, 0.063, 1.05
No. of reflections	3400
No. of parameters	190
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.00, −0.59

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001).

Acknowledgements

Financial support from the NRF (Thuthuka) and University of the Western Cape Senate Research is greatly acknowledged. We also thank Professor Roger A. Lalancette for resolving the symmetry-related geometries.

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