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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890

Di­bromidobis[1-(2,4,6-tri­methyl­phen­yl)-1,4,5,6-tetra­hydro­pyrimidine-κN3]palladium(II)

aDepartment of Chemistry, Zhengzhou University, Zhengzhou 450001, People's Republic of China, and bSchool of Chemistry and Chemical Engineering, Henan University of Technology, Zhengzhou 450001, People's Republic of China
*Correspondence e-mail: henangongda@yahoo.com

(Received 5 November 2010; accepted 5 December 2010; online 11 December 2010)

In the title complex, [PdBr2(C13H18N2)2], the PdII atom is situated on an inversion center. The tetra­hydro­pyrimidine group of the N-(2,4,6-trimethyl­phen­yl)-1,4,5,6-tetra­hydro­pyrimidine ligand is twisted from the square (PdN2Br2) coordination plane with a C—N—Pd—Br torsion angle of 81.8 (4)°; this is different from the angle of 43.47 (14)°, reported in a closely related structure, dichloridobis(1-methyl-1,4,5,6-tetra­hydro­pyrimidine)­palladium(II).

Related literature

For the related structure, dichloro­bis­(1-methyl-1,4,5,6-tetra­hydro­pyrimidine)­palladium(II), see: Chang & Lee (2007[Chang, C.-F. & Lee, H. M. (2007). Acta Cryst. E63, m167-m168.]).

[Scheme 1]

Experimental

Crystal data
  • [PdBr2(C13H18N2)2]

  • Mr = 670.81

  • Monoclinic, P 21 /c

  • a = 7.1348 (14) Å

  • b = 21.308 (4) Å

  • c = 8.9704 (18) Å

  • β = 94.60 (3)°

  • V = 1359.4 (5) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 3.64 mm−1

  • T = 293 K

  • 0.20 × 0.20 × 0.20 mm

Data collection
  • Rigaku Saturn 724 CCD area-detector diffractometer

  • Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2006[Rigaku/MSC (2006). CrystalClear. Rigaku/MSC Inc., Tokyo, Japan.]) Tmin = 0.530, Tmax = 0.530

  • 6809 measured reflections

  • 2393 independent reflections

  • 1931 reflections with I > 2σ(I)

  • Rint = 0.034

Refinement
  • R[F2 > 2σ(F2)] = 0.045

  • wR(F2) = 0.114

  • S = 1.08

  • 2393 reflections

  • 154 parameters

  • H-atom parameters constrained

  • Δρmax = 0.76 e Å−3

  • Δρmin = −0.50 e Å−3

Data collection: CrystalClear (Rigaku/MSC, 2006[Rigaku/MSC (2006). CrystalClear. Rigaku/MSC Inc., Tokyo, Japan.]); cell refinement: CrystalClear; data reduction: CrystalClear; 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: SHELXL97.

Supporting information


Comment top

Our group is interested in the preparation of new N-heterocyclic carbene (NHC) ligands based on substituted 1,4,5,6-tetrahydropyrimidine and their palladium complexes. In the course of preparing the palladium complex of a bidentate NHC ligand, we observed that the reaction of the corresponding tetrahydropyrimidine salt and Pd(OAc)2, unexpectedly, under unoptimized reaction conditions, afforded the title compound.

In the title compound the Pd atom is situated on a center of inversion (Fig. 1). The organic ligands twist away from the square (PdN2Br2) coordination plane with a C1—N1—Pd1—Br1 torsion angle of 81.8 (4)°. The corresponding angle in the closely related structure, dichlorobis(1-methyl-1,4,5,6-tetrahydropyrimidine)palladium(II) [Chang & Lee, 2007], is 43.47 (14)°.

Related literature top

For the related structure, dichlorobis(1-methyl-1,4,5,6-tetrahydropyrimidine)palladium(II), see: Chang & Lee (2007).

Experimental top

Pd(OAc)2 (101 mg, 0.45 mmol) was added to a solution of N,N-methylene-N',N'-bis-2,4,6-trimethylphenyl-1,4,5,6-tetrahydropyrimidine (260 mg, 0.45 mmol) in DMSO (3 ml). The mixture was then heated at 333 K for 5 h. After cooling, the solvent was removed completely under vacuum. The residue was then dissolved in CHCl3, and filtered. Evaporation of the filtrate afforded an orange solid (yield 200 mg, 66%). Crystals of the title complex, suitable for structural analysis, were obtained by vapor diffusion of diethyl ether into an acetonitrile solution containing the solid.

Refinement top

The hydrogen atoms were included in calculated positions and treated as riding: C-H = 0.93, 0.97 and 0.96 Å, for CH, CH2 and CH3 H-atoms, respectively, with Uiso(H) = k × Ueq(C), where k = 1.5 for CH3 H-atoms and k = 1.2 for all other H-atoms.

Structure description top

Our group is interested in the preparation of new N-heterocyclic carbene (NHC) ligands based on substituted 1,4,5,6-tetrahydropyrimidine and their palladium complexes. In the course of preparing the palladium complex of a bidentate NHC ligand, we observed that the reaction of the corresponding tetrahydropyrimidine salt and Pd(OAc)2, unexpectedly, under unoptimized reaction conditions, afforded the title compound.

In the title compound the Pd atom is situated on a center of inversion (Fig. 1). The organic ligands twist away from the square (PdN2Br2) coordination plane with a C1—N1—Pd1—Br1 torsion angle of 81.8 (4)°. The corresponding angle in the closely related structure, dichlorobis(1-methyl-1,4,5,6-tetrahydropyrimidine)palladium(II) [Chang & Lee, 2007], is 43.47 (14)°.

For the related structure, dichlorobis(1-methyl-1,4,5,6-tetrahydropyrimidine)palladium(II), see: Chang & Lee (2007).

Computing details top

Data collection: CrystalClear (Rigaku/MSC, 2006); cell refinement: CrystalClear (Rigaku/MSC, 2006); data reduction: CrystalClear (Rigaku/MSC, 2006); 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: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title molecule, showing 30% probability displacement ellipsoids.
Dibromidobis[1-(2,4,6-trimethylphenyl)-1,4,5,6-tetrahydropyrimidine- κN3]palladium(II) top
Crystal data top
[PdBr2(C13H18N2)2]F(000) = 672
Mr = 670.81Dx = 1.639 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3263 reflections
a = 7.1348 (14) Åθ = 2.5–27.9°
b = 21.308 (4) ŵ = 3.64 mm1
c = 8.9704 (18) ÅT = 293 K
β = 94.60 (3)°Prismatic, colourless
V = 1359.4 (5) Å30.20 × 0.20 × 0.20 mm
Z = 2
Data collection top
Rigaku CCD area-detector
diffractometer
2393 independent reflections
Radiation source: fine-focus sealed tube1931 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.034
ω scansθmax = 25.0°, θmin = 2.5°
Absorption correction: multi-scan
(CrystalClear; Rigaku/MSC, 2006)
h = 85
Tmin = 0.530, Tmax = 0.530k = 1825
6809 measured reflectionsl = 910
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)] = 0.045Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.114H-atom parameters constrained
S = 1.08 w = 1/[σ2(Fo2) + (0.0553P)2]
where P = (Fo2 + 2Fc2)/3
2393 reflections(Δ/σ)max < 0.001
154 parametersΔρmax = 0.76 e Å3
0 restraintsΔρmin = 0.50 e Å3
Crystal data top
[PdBr2(C13H18N2)2]V = 1359.4 (5) Å3
Mr = 670.81Z = 2
Monoclinic, P21/cMo Kα radiation
a = 7.1348 (14) ŵ = 3.64 mm1
b = 21.308 (4) ÅT = 293 K
c = 8.9704 (18) Å0.20 × 0.20 × 0.20 mm
β = 94.60 (3)°
Data collection top
Rigaku CCD area-detector
diffractometer
2393 independent reflections
Absorption correction: multi-scan
(CrystalClear; Rigaku/MSC, 2006)
1931 reflections with I > 2σ(I)
Tmin = 0.530, Tmax = 0.530Rint = 0.034
6809 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0450 restraints
wR(F2) = 0.114H-atom parameters constrained
S = 1.08Δρmax = 0.76 e Å3
2393 reflectionsΔρmin = 0.50 e Å3
154 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
Pd10.50000.50000.00000.0445 (2)
Br10.27385 (9)0.45987 (3)0.19525 (7)0.0700 (2)
N10.3804 (6)0.44800 (17)0.1532 (5)0.0502 (11)
N20.4027 (6)0.36304 (16)0.3218 (5)0.0513 (11)
C10.2139 (8)0.4701 (2)0.2167 (6)0.0595 (16)
H1A0.10440.45450.15700.071*
H1B0.21110.51560.21180.071*
C20.2026 (10)0.4506 (2)0.3718 (7)0.0722 (19)
H2A0.07830.46070.40150.087*
H2B0.29290.47470.43480.087*
C30.2385 (8)0.3831 (2)0.3997 (7)0.0659 (17)
H3A0.26220.37570.50620.079*
H3B0.12900.35890.36380.079*
C40.4604 (8)0.3983 (2)0.2102 (6)0.0534 (14)
H40.57000.38550.16950.064*
C50.5155 (7)0.3102 (2)0.3749 (6)0.0461 (12)
C60.4605 (8)0.2496 (2)0.3291 (6)0.0541 (14)
C70.5759 (8)0.1998 (2)0.3757 (6)0.0586 (15)
H70.53890.15920.34910.070*
C80.7456 (8)0.2088 (3)0.4614 (7)0.0631 (16)
C90.7929 (8)0.2699 (2)0.5081 (7)0.0628 (15)
H90.90270.27660.56910.075*
C100.6784 (8)0.3208 (2)0.4650 (7)0.0561 (14)
C110.2792 (9)0.2376 (3)0.2354 (7)0.0757 (18)
H11A0.17560.25270.28710.114*
H11B0.26490.19330.21800.114*
H11C0.28170.25900.14150.114*
C120.8751 (9)0.1538 (3)0.5026 (9)0.087 (2)
H12A0.98020.15480.44230.130*
H12B0.80740.11520.48550.130*
H12C0.91940.15670.60630.130*
C130.7335 (9)0.3853 (3)0.5220 (8)0.081 (2)
H13A0.75280.41230.43900.122*
H13B0.84770.38260.58610.122*
H13C0.63520.40210.57730.122*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Pd10.0507 (4)0.0410 (3)0.0427 (4)0.0089 (2)0.0098 (3)0.0122 (2)
Br10.0733 (5)0.0738 (4)0.0615 (5)0.0017 (3)0.0030 (3)0.0054 (3)
N10.054 (3)0.045 (2)0.053 (3)0.0112 (19)0.012 (2)0.0117 (19)
N20.066 (3)0.038 (2)0.052 (3)0.0043 (19)0.016 (2)0.0131 (18)
C10.060 (4)0.046 (3)0.075 (4)0.014 (2)0.023 (3)0.010 (3)
C20.084 (5)0.061 (3)0.076 (5)0.027 (3)0.034 (4)0.016 (3)
C30.078 (4)0.055 (3)0.070 (4)0.013 (3)0.040 (4)0.011 (3)
C40.056 (4)0.052 (3)0.054 (3)0.005 (2)0.020 (3)0.005 (2)
C50.048 (3)0.041 (3)0.049 (3)0.008 (2)0.006 (2)0.010 (2)
C60.068 (4)0.042 (3)0.053 (3)0.004 (2)0.005 (3)0.004 (2)
C70.071 (4)0.036 (3)0.069 (4)0.004 (2)0.006 (3)0.004 (2)
C80.058 (4)0.056 (3)0.077 (4)0.011 (3)0.017 (3)0.019 (3)
C90.049 (4)0.061 (3)0.077 (4)0.002 (3)0.006 (3)0.011 (3)
C100.057 (4)0.039 (3)0.073 (4)0.002 (2)0.005 (3)0.006 (2)
C110.085 (5)0.057 (3)0.081 (5)0.006 (3)0.017 (4)0.016 (3)
C120.070 (5)0.070 (4)0.121 (6)0.023 (3)0.014 (4)0.031 (4)
C130.073 (4)0.054 (3)0.115 (6)0.012 (3)0.009 (4)0.006 (3)
Geometric parameters (Å, º) top
Pd1—N1i2.008 (4)C5—C61.402 (7)
Pd1—N12.008 (4)C6—C71.386 (7)
Pd1—Br1i2.4391 (9)C6—C111.507 (8)
Pd1—Br12.4391 (9)C7—C81.394 (8)
N1—C41.289 (6)C7—H70.9300
N1—C11.437 (6)C8—C91.401 (8)
N2—C41.343 (6)C8—C121.519 (7)
N2—C51.442 (6)C9—C101.394 (7)
N2—C31.474 (6)C9—H90.9300
C1—C21.461 (8)C10—C131.508 (7)
C1—H1A0.9700C11—H11A0.9600
C1—H1B0.9700C11—H11B0.9600
C2—C31.478 (7)C11—H11C0.9600
C2—H2A0.9700C12—H12A0.9600
C2—H2B0.9700C12—H12B0.9600
C3—H3A0.9700C12—H12C0.9600
C3—H3B0.9700C13—H13A0.9600
C4—H40.9300C13—H13B0.9600
C5—C101.380 (7)C13—H13C0.9600
N1i—Pd1—N1180.000 (1)C6—C5—N2119.1 (5)
N1i—Pd1—Br1i90.30 (14)C7—C6—C5118.1 (5)
N1—Pd1—Br1i89.70 (14)C7—C6—C11120.0 (5)
N1i—Pd1—Br189.70 (13)C5—C6—C11121.8 (5)
N1—Pd1—Br190.30 (14)C6—C7—C8122.0 (5)
Br1i—Pd1—Br1180.0C6—C7—H7119.0
C4—N1—C1117.8 (4)C8—C7—H7119.0
C4—N1—Pd1121.7 (3)C7—C8—C9118.0 (5)
C1—N1—Pd1120.0 (3)C7—C8—C12120.9 (5)
C4—N2—C5119.1 (4)C9—C8—C12121.1 (6)
C4—N2—C3119.6 (4)C10—C9—C8121.2 (6)
C5—N2—C3120.9 (4)C10—C9—H9119.4
N1—C1—C2113.2 (4)C8—C9—H9119.4
N1—C1—H1A108.9C5—C10—C9118.9 (4)
C2—C1—H1A108.9C5—C10—C13122.1 (5)
N1—C1—H1B108.9C9—C10—C13118.9 (5)
C2—C1—H1B108.9C6—C11—H11A109.5
H1A—C1—H1B107.7C6—C11—H11B109.5
C1—C2—C3114.5 (5)H11A—C11—H11B109.5
C1—C2—H2A108.6C6—C11—H11C109.5
C3—C2—H2A108.6H11A—C11—H11C109.5
C1—C2—H2B108.6H11B—C11—H11C109.5
C3—C2—H2B108.6C8—C12—H12A109.5
H2A—C2—H2B107.6C8—C12—H12B109.5
N2—C3—C2109.6 (4)H12A—C12—H12B109.5
N2—C3—H3A109.7C8—C12—H12C109.5
C2—C3—H3A109.7H12A—C12—H12C109.5
N2—C3—H3B109.7H12B—C12—H12C109.5
C2—C3—H3B109.7C10—C13—H13A109.5
H3A—C3—H3B108.2C10—C13—H13B109.5
N1—C4—N2127.1 (5)H13A—C13—H13B109.5
N1—C4—H4116.5C10—C13—H13C109.5
N2—C4—H4116.5H13A—C13—H13C109.5
C10—C5—C6121.6 (4)H13B—C13—H13C109.5
C10—C5—N2119.2 (4)
Br1i—Pd1—N1—C473.6 (4)C3—N2—C5—C685.6 (7)
Br1—Pd1—N1—C4106.4 (4)C10—C5—C6—C70.7 (8)
Br1i—Pd1—N1—C198.2 (4)N2—C5—C6—C7177.0 (4)
Br1—Pd1—N1—C181.8 (4)C10—C5—C6—C11177.7 (5)
C4—N1—C1—C224.7 (8)N2—C5—C6—C114.7 (8)
Pd1—N1—C1—C2147.4 (4)C5—C6—C7—C82.2 (8)
N1—C1—C2—C348.5 (8)C11—C6—C7—C8179.4 (5)
C4—N2—C3—C218.5 (8)C6—C7—C8—C93.9 (8)
C5—N2—C3—C2154.1 (5)C6—C7—C8—C12176.1 (5)
C1—C2—C3—N244.1 (8)C7—C8—C9—C102.9 (9)
C1—N1—C4—N21.8 (9)C12—C8—C9—C10177.2 (5)
Pd1—N1—C4—N2173.8 (4)C6—C5—C10—C91.7 (8)
C5—N2—C4—N1177.5 (5)N2—C5—C10—C9176.0 (5)
C3—N2—C4—N14.7 (9)C6—C5—C10—C13176.5 (5)
C4—N2—C5—C1075.9 (7)N2—C5—C10—C135.8 (8)
C3—N2—C5—C1096.7 (6)C8—C9—C10—C50.1 (8)
C4—N2—C5—C6101.8 (6)C8—C9—C10—C13178.4 (6)
Symmetry code: (i) x+1, y+1, z.

Experimental details

Crystal data
Chemical formula[PdBr2(C13H18N2)2]
Mr670.81
Crystal system, space groupMonoclinic, P21/c
Temperature (K)293
a, b, c (Å)7.1348 (14), 21.308 (4), 8.9704 (18)
β (°) 94.60 (3)
V3)1359.4 (5)
Z2
Radiation typeMo Kα
µ (mm1)3.64
Crystal size (mm)0.20 × 0.20 × 0.20
Data collection
DiffractometerRigaku CCD area-detector
Absorption correctionMulti-scan
(CrystalClear; Rigaku/MSC, 2006)
Tmin, Tmax0.530, 0.530
No. of measured, independent and
observed [I > 2σ(I)] reflections
6809, 2393, 1931
Rint0.034
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.045, 0.114, 1.08
No. of reflections2393
No. of parameters154
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.76, 0.50

Computer programs: CrystalClear (Rigaku/MSC, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

 

Acknowledgements

The authors thank Mr H. Qian for technical assistance. This research was supported by the National Natural Science Foundation of the People's Republic of China (grant No. 20902017).

References

First citationChang, C.-F. & Lee, H. M. (2007). Acta Cryst. E63, m167–m168.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationRigaku/MSC (2006). CrystalClear. Rigaku/MSC Inc., Tokyo, Japan.  Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Follow Acta Cryst. E
Sign up for e-alerts
Follow Acta Cryst. on Twitter
Follow us on facebook
Sign up for RSS feeds