trans-Dichloridobis(2,4-dimethyl­aniline-κN)palladium(II)

Pan, Y.; Guo, H.-F.; Ma, D.-Y.; Lu, K.

doi:10.1107/S1600536812015279

metal-organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 68| Part 5| May 2012| Page m592

doi:10.1107/S1600536812015279

Open

access

trans-Dichloridobis(2,4-dimethylaniline-κN)palladium(II)

Yong Pan,^a,^b Hai-Fu Guo,^a ^* De-Yun Ma ^a and Kuan Lu ^a

^aCollege of Chemistry and Chemical Engineering, Zhaoqing University, Zhaoqing 526061, People's Republic of China, and ^bCollege of Chemical Engineering, Inner Mongolia University of Technology, Inner Mongolia 010051, People's Republic of China
^*Correspondence e-mail: guohaifu@zqu.edu.cn

(Received 2 April 2012; accepted 7 April 2012; online 13 April 2012)

In the title compound, [PdCl₂(C₈H₁₁N)₂], the Pd^II atom is located on a crystallographic inversion center and adopts a square-planar coordination geometry, with pairs of equivalent ligands in trans positions. In the crystal, adjacent molecules are linked with each other through weak N—H⋯Cl hydrogen bonds and π–π stacking interactions between the phenyl rings [shortest centroid–centroid distance = 3.720 (2) Å], leading to the formation of layers parallel to the a-axis direction.

Related literature

For general background to the application of palladium compounds in homogeneous and heterogeneous catalysis, see: Padmanabhan et al. (1985 ); Hartley (1973 ). For related structures, see: Newkome et al. (1982 ); Chen et al. (2002 ).

Experimental

Crystal data

[PdCl₂(C₈H₁₁N)₂]
M_r = 419.66
Monoclinic, P 2₁ /c
a = 14.315 (6) Å
b = 8.081 (3) Å
c = 7.420 (3) Å
β = 104.705 (7)°
V = 830.3 (6) Å³
Z = 2
Mo Kα radiation
μ = 1.43 mm⁻¹
T = 246 K
0.30 × 0.28 × 0.22 mm

Data collection

Bruker APEXII area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.669, T_max = 0.740
4058 measured reflections
1485 independent reflections
1226 reflections with I > 2σ(I)
R_int = 0.027

Refinement

R[F² > 2σ(F²)] = 0.029
wR(F²) = 0.076
S = 1.06
1485 reflections
99 parameters
H-atom parameters constrained
Δρ_max = 1.65 e Å⁻³
Δρ_min = −0.66 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1B⋯Cl1ⁱ	0.91	2.68	3.376 (3)	134
N1—H1A⋯Cl1ⁱⁱ	0.91	2.39	3.287 (3)	168
Symmetry codes: (i) $[-x+1, y+{\script{1\over 2}}, -z+{\script{5\over 2}}]$ ; (ii) $[x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812015279/zl2469sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812015279/zl2469Isup2.hkl

checkCIF report

Comment top

Palladium compounds have attracted much attention due to their application in homogeneous and heterogeneous catalyses (Padmanabhan et al. 1985). Some dramatic results in homogeneous catalysis of reactions of organic compounds, particularly the successful commercial exploitation of the Wacker one stage process for the homogeneous catalytic oxidation of ethylene to acetaldehyde in the presence of palladium (II) chloride (Hartley 1973), have contributed to this interest. In this paper we report crystallization of the title compound, a new palladium(II) complex obtained by the reaction of 2,4-dimethylaniline with palladium chloride in ethanol. As illustrated in Fig.1, the Pd^II atom exhibits a square-planar coordination sphere, defined by two N atoms from two 2,4-dimethylaniline and two chloride atoms. The molecule adopts the trans configuration in the solid state. The bond distances of Pd—N (2.055 (2)) and Pd—Cl (2.293 (3) Å) are comparable with the values found in related complexes (Newkome et al. 1982; Chen et al. 2002). The dihedral angle between the plane of the phenyl ring and the square plane around Pd is 63.03 (1) °. In the crystal structure, intermolecular N—H···Cl hydrogen bonding interactions involving the amino groups and chlorine anions (Table 1) and π–π stacking interactions (centroid-centroid distance = 3.720 (2) Å) occurring between neighboring phenyl rings of centrosymmetrically related complexes form a layer network running parallel to the a axis (Fig. 2).

Related literature top

For general background to the application of palladium compounds in homogeneous and heterogeneous catalysis, see: Padmanabhan et al. (1985); Hartley (1973). For related structures, see: Newkome et al. (1982); Chen et al. (2002).

Experimental top

A mixture of palladium chloride (0.1 mmol, 0.018 g) and 2,4-dimethylaniline (0.2 mmol, 0.024 g) in 12 ml of anhydrous ethanol was sealed in an autoclave equipped with a Teflon liner (25 ml) and then heated at 353 K for 1 day. Yellow crystals were obtained by slow evaporation of the solvent at room temperature (0.093 g, 45%). IR (KBr pellet) (cm^-1): 3452(s), 3023(m), 2928(m), 1619(s), 1582(s), 1556(m), 1488(s), 1452(m), 1383(s), 1283(w), 1231(w), 1184(w), 1143(m), 1106(s), 1053(m), 979(w), 954(w), 891(m), 817(s), 738(m), 607(w), 575(m), 466(m), 424(m).

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the title compound, showing 30% probability displacement ellipsoids. Symmetry code: (i) 1 - x, 1 - y, 2 - z.
	Fig. 2. View of one of the two-dimensional layers of the title compound. The intermolecular hydrogen bonds and π–π stacking interactions are shown as turquiose and red dashed lines, respectively. H atoms not involved in hydrogen bonds have been omitted for clarity.

trans-Dichloridobis(2,4-dimethylaniline-κN)palladium(II) top

Crystal data top

[PdCl₂(C₈H₁₁N)₂]	F(000) = 424
M_r = 419.66	D_x = 1.679 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 5300 reflections
a = 14.315 (6) Å	θ = 1.3–28.0°
b = 8.081 (3) Å	µ = 1.43 mm⁻¹
c = 7.420 (3) Å	T = 246 K
β = 104.705 (7)°	Block, yellow
V = 830.3 (6) Å³	0.30 × 0.28 × 0.22 mm
Z = 2

Data collection top

Bruker APEXII area-detector diffractometer	1485 independent reflections
Radiation source: fine-focus sealed tube	1226 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.027
ϕ and ω scan	θ_max = 25.2°, θ_min = 2.9°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −17→8
T_min = 0.669, T_max = 0.740	k = −9→9
4058 measured reflections	l = −8→8

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)] = 0.029	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.076	H-atom parameters constrained
S = 1.06	w = 1/[σ²(F_o²) + (0.0402P)² + 0.6953P] where P = (F_o² + 2F_c²)/3
1485 reflections	(Δ/σ)_max < 0.001
99 parameters	Δρ_max = 1.65 e Å⁻³
0 restraints	Δρ_min = −0.66 e Å⁻³

Crystal data top

[PdCl₂(C₈H₁₁N)₂]	V = 830.3 (6) Å³
M_r = 419.66	Z = 2
Monoclinic, P2₁/c	Mo Kα radiation
a = 14.315 (6) Å	µ = 1.43 mm⁻¹
b = 8.081 (3) Å	T = 246 K
c = 7.420 (3) Å	0.30 × 0.28 × 0.22 mm
β = 104.705 (7)°

Data collection top

Bruker APEXII area-detector diffractometer	1485 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	1226 reflections with I > 2σ(I)
T_min = 0.669, T_max = 0.740	R_int = 0.027
4058 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.029	0 restraints
wR(F²) = 0.076	H-atom parameters constrained
S = 1.06	Δρ_max = 1.65 e Å⁻³
1485 reflections	Δρ_min = −0.66 e Å⁻³
99 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

	x	y	z	U_iso*/U_eq
C1	0.3227 (3)	0.3340 (4)	1.0653 (5)	0.0177 (7)
C2	0.2358 (3)	0.4055 (4)	0.9726 (5)	0.0238 (8)
C3	0.1603 (3)	0.3005 (4)	0.8916 (6)	0.0270 (9)
H3	0.1009	0.3471	0.8282	0.032*
C4	0.1686 (3)	0.1303 (4)	0.9001 (6)	0.0257 (9)
C5	0.2558 (3)	0.0642 (4)	0.9939 (5)	0.0242 (8)
H5	0.2633	−0.0514	1.0016	0.029*
C6	0.3321 (3)	0.1643 (4)	1.0765 (5)	0.0203 (8)
H6	0.3911	0.1170	1.1410	0.024*
C7	0.2219 (3)	0.5877 (5)	0.9583 (7)	0.0365 (11)
H7A	0.2382	0.6358	1.0822	0.055*
H7B	0.1550	0.6121	0.8973	0.055*
H7C	0.2633	0.6342	0.8862	0.055*
C8	0.0835 (3)	0.0239 (5)	0.8099 (7)	0.0385 (11)
H8A	0.0807	0.0104	0.6787	0.058*
H8B	0.0246	0.0762	0.8228	0.058*
H8C	0.0903	−0.0837	0.8698	0.058*
Cl1	0.55490 (6)	0.23246 (9)	1.01658 (12)	0.0208 (2)
N1	0.4044 (2)	0.4353 (3)	1.1530 (4)	0.0181 (6)
H1A	0.4382	0.3811	1.2567	0.022*
H1B	0.3815	0.5302	1.1918	0.022*
Pd1	0.5000	0.5000	1.0000	0.01533 (14)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0191 (18)	0.0188 (16)	0.0165 (18)	−0.0024 (14)	0.0070 (15)	−0.0018 (14)
C2	0.022 (2)	0.0193 (18)	0.029 (2)	−0.0006 (16)	0.0055 (17)	0.0025 (15)
C3	0.0184 (19)	0.0231 (19)	0.037 (2)	0.0011 (16)	0.0018 (17)	0.0026 (17)
C4	0.025 (2)	0.0218 (18)	0.031 (2)	−0.0067 (17)	0.0068 (18)	−0.0052 (15)
C5	0.029 (2)	0.0158 (16)	0.030 (2)	−0.0039 (16)	0.0114 (18)	−0.0018 (15)
C6	0.022 (2)	0.0186 (16)	0.0195 (19)	0.0013 (15)	0.0047 (16)	0.0025 (14)
C7	0.026 (2)	0.0183 (19)	0.061 (3)	0.0018 (17)	0.003 (2)	0.0023 (19)
C8	0.026 (2)	0.031 (2)	0.055 (3)	−0.0114 (19)	0.006 (2)	−0.008 (2)
Cl1	0.0274 (5)	0.0131 (4)	0.0224 (4)	0.0013 (4)	0.0071 (4)	0.0008 (3)
N1	0.0223 (16)	0.0142 (13)	0.0168 (15)	−0.0007 (12)	0.0033 (13)	−0.0007 (12)
Pd1	0.0192 (2)	0.0107 (2)	0.0155 (2)	−0.00095 (15)	0.00342 (15)	−0.00031 (14)

Geometric parameters (Å, º) top

C1—C6	1.378 (5)	C7—H7A	0.9700
C1—C2	1.385 (5)	C7—H7B	0.9700
C1—N1	1.441 (4)	C7—H7C	0.9700
C2—C3	1.385 (5)	C8—H8A	0.9700
C2—C7	1.486 (5)	C8—H8B	0.9700
C3—C4	1.381 (5)	C8—H8C	0.9700
C3—H3	0.9400	Cl1—Pd1	2.2930 (11)
C4—C5	1.373 (5)	N1—Pd1	2.055 (3)
C4—C8	1.503 (5)	N1—H1A	0.9100
C5—C6	1.372 (5)	N1—H1B	0.9100
C5—H5	0.9400	Pd1—N1ⁱ	2.055 (3)
C6—H6	0.9400	Pd1—Cl1ⁱ	2.2930 (11)

C6—C1—C2	120.4 (3)	C2—C7—H7C	109.5
C6—C1—N1	118.8 (3)	H7A—C7—H7C	109.5
C2—C1—N1	120.8 (3)	H7B—C7—H7C	109.5
C1—C2—C3	117.6 (3)	C4—C8—H8A	109.5
C1—C2—C7	122.4 (3)	C4—C8—H8B	109.5
C3—C2—C7	120.0 (3)	H8A—C8—H8B	109.5
C4—C3—C2	122.8 (4)	C4—C8—H8C	109.5
C4—C3—H3	118.6	H8A—C8—H8C	109.5
C2—C3—H3	118.6	H8B—C8—H8C	109.5
C5—C4—C3	117.9 (3)	C1—N1—Pd1	118.3 (2)
C5—C4—C8	122.2 (3)	C1—N1—H1A	107.7
C3—C4—C8	120.0 (4)	Pd1—N1—H1A	107.7
C4—C5—C6	121.0 (3)	C1—N1—H1B	107.7
C4—C5—H5	119.5	Pd1—N1—H1B	107.7
C6—C5—H5	119.5	H1A—N1—H1B	107.1
C5—C6—C1	120.4 (3)	N1—Pd1—N1ⁱ	180.0
C5—C6—H6	119.8	N1—Pd1—Cl1	89.86 (8)
C1—C6—H6	119.8	N1ⁱ—Pd1—Cl1	90.14 (8)
C2—C7—H7A	109.5	N1—Pd1—Cl1ⁱ	90.14 (8)
C2—C7—H7B	109.5	N1ⁱ—Pd1—Cl1ⁱ	89.86 (8)
H7A—C7—H7B	109.5	Cl1—Pd1—Cl1ⁱ	180.0

Symmetry code: (i) −x+1, −y+1, −z+2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1B···Cl1ⁱⁱ	0.91	2.68	3.376 (3)	134
N1—H1A···Cl1ⁱⁱⁱ	0.91	2.39	3.287 (3)	168

Symmetry codes: (ii) −x+1, y+1/2, −z+5/2; (iii) x, −y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formula	[PdCl₂(C₈H₁₁N)₂]
M_r	419.66
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	246
a, b, c (Å)	14.315 (6), 8.081 (3), 7.420 (3)
β (°)	104.705 (7)
V (Å³)	830.3 (6)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	1.43
Crystal size (mm)	0.30 × 0.28 × 0.22

Data collection
Diffractometer	Bruker APEXII area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.669, 0.740
No. of measured, independent and observed [I > 2σ(I)] reflections	4058, 1485, 1226
R_int	0.027
(sin θ/λ)_max (Å⁻¹)	0.599

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.029, 0.076, 1.06
No. of reflections	1485
No. of parameters	99
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.65, −0.66

Computer programs: APEX2 (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP in SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1B···Cl1ⁱ	0.91	2.68	3.376 (3)	134.0
N1—H1A···Cl1ⁱⁱ	0.91	2.39	3.287 (3)	168.2

Symmetry codes: (i) −x+1, y+1/2, −z+5/2; (ii) x, −y+1/2, z+1/2.

Acknowledgements

The authors acknowledge Zhaoqing University for supporting this work.

References

Bruker (2004). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Chen, Y. B., Li, Z. J., Qin, Y. Y., Kang, Y., Wu, L. & Yao, Y. G. (2002). Chin. J. Struct. Chem. 21, 530–532. CAS Google Scholar
Hartley, F. R. (1973). In The Chemistry of Platinum and Palladium. New York: John Wiley and Sons. Google Scholar
Newkome, G. R., Fronczek, F. R., Grupta, V. K., Puckett, W. E., Pantaleo, D. C. & Kiefer, G. E. (1982). J. Am. Chem. Soc. 104, 1782–1783. CSD CrossRef CAS Web of Science Google Scholar
Padmanabhan, V. M., Patel, R. P. & Ranganathan, T. N. (1985). Acta Cryst. C41, 1305–1307. CSD CrossRef CAS Web of Science IUCr Journals Google Scholar
Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar