cis-Dibromidobis(2-phenyl­pyridine-κN)platinum(II)

In the title complex, [PtBr₂(C₁₁H₉N)₂], the Pt^II ion has a distorted cis-Br₂N₂ square-planar coordination geometry defined by two N atoms from two 2-phenyl­pyridine (ppy) ligands and two Br⁻ anions. The ppy ligands are not planar, the dihedral angles between the pyridine and benzene rings being 49.0 (3) and 47.3 (3)°. In the crystal, the complex mol­ecules are stacked in columns along the a axis. In the columns, there are numerous intra- and inter­molecular π–π inter­actions between the six-membered rings, the shortest ring centroid–centroid distance being 3.774 (6) Å.

Key indicators

• Single-crystal X-ray study
• T = 200 K
• Mean [sigma](C-C) = 0.015 Å
• R factor = 0.028
• wR factor = 0.068
• Data-to-parameter ratio = 12.0

checkCIF/PLATON results

No syntax errors found





Alert level A
PLAT900_ALERT_1_A No Matching Reflection File Found ..............          !

Alert level C
PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low .......      0.972
PLAT342_ALERT_3_C Low Bond Precision on  C-C Bonds ...............     0.0155 Ang
PLAT925_ALERT_1_C The Reported and Calculated Rho(max) Differ by .       1.73 eA-3

Alert level G
REFLT03_ALERT_4_G  WARNING: Large fraction of Friedel related reflns may
                     be needed to determine absolute structure
           From the CIF: _diffrn_reflns_theta_max           26.04
           From the CIF: _reflns_number_total               2931
           Count of symmetry unique reflns         2075
           Completeness (_total/calc)            141.25%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured       856
           Fraction of Friedel pairs measured     0.413
           Are heavy atom types Z>Si present        yes
PLAT005_ALERT_5_G No _iucr_refine_instructions_details in CIF ....          ?
PLAT033_ALERT_4_G Flack x Parameter Value Deviates from Zero .....     -0.037

   1 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   3 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   3 ALERT level G = General information/check it is not something unexpected

   2 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   2 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

---

S1. Comment

Crystal structures of the related Pt^II and Pd^II complexes, such as cis-[PtCl₂(ppy)₂] (ppy = 2-phenylpyridine, C₁₁H₉N) (Yoshinari et al., 2010) and trans-[PdX₂(ppy)₂] (X = Cl or I) (Ha, 2011; Ha, 2012), have been investigated previously.

The Pt^II ion in the title complex, [PtBr₂(ppy)₂], has a distorted cis-Br₂N₂ square-planar coordination geometry defined by two N atoms from two ppy ligands and two Br^- anions (Fig. 1). The Pt—N and Pt—Br bond lengths are nearly equivalent, respectively (Table 1). In the crystal, the two pyridine rings are inclined to the least-squares plane of the PtBr₂N₂ unit [maximum deviation = 0.092 (4) Å], making dihedral angles of 61.6 (2)° and 64.0 (2)°. The ppy ligands are not planar, the dihedral angles between the pyridine and benzene rings being 49.0 (3)° and 47.3 (3)°. The complex molecules are stacked in columns along the a axis. In the columns, numerous intra- and intermolecular π-π interactions between the six-membered rings are present, the shortest ring centroid-centroid distance being 3.774 (6) Å (Fig. 2).

Related literature

For the crystal structures of the related Pt^II and Pd^II complexes, cis-[PtCl₂(ppy)₂] and trans-[PdX₂(ppy)₂] (X = Cl or I), see: Yoshinari et al. (2010); Ha (2011, 2012).

S2. Experimental

To a solution of K₂PtBr₄ (0.2391 g, 0.403 mmol) in H₂O (20 ml)/MeOH (100 ml) was added 2-phenylpyridine (0.1810 g, 1.166 mmol) and stirred for 7 h at room temperature. The formed brown precipitate was removed by filtration and the solvent of the filtrate was evaporated. The residue was washed with H₂O and dried at 323 K, to give a yellow powder (0.1672 g). Crystals suitable for X-ray analysis were obtained by slow evaporation from a CH₃CN solution at room temperature.

S3. Refinement

H atoms were positioned geometrically and allowed to ride on their respective parent atoms: C—H = 0.95 Å and U_iso(H) = 1.2U_eq(C). The highest peak (1.73 e Å^-3) and the deepest hole (-0.93 e Å^-3) in the difference Fourier map are located 1.31 Å and 0.88 Å, respectively, from the atoms H11 and Pt1.

Computing details

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures

Fig. 1. A view of the molecular structure of the title complex, with displacement ellipsoids drawn at the 40% probability level and the atom numbering.

Fig. 2. A view of the unit-cell contents of the title complex.

cis-Dibromidobis(2-phenylpyridine-κN)platinum(II)

Crystal data

[PtBr2(C11H9N)2]	F(000) = 1248
Mr = 665.29	Dx = 2.106 Mg m^−3
Monoclinic, Cc	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: C -2yc	Cell parameters from 4325 reflections
a = 7.6268 (9) Å	θ = 2.2–26.0°
b = 18.277 (2) Å	µ = 10.51 mm^−1
c = 15.1626 (18) Å	T = 200 K
β = 96.948 (2)°	Stick, yellow
V = 2098.1 (4) Å^3	0.24 × 0.20 × 0.14 mm
Z = 4

Data collection

Bruker SMART 1000 CCD diffractometer	2931 independent reflections
Radiation source: fine-focus sealed tube	2645 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.029
ϕ and ω scans	θmax = 26.0°, θmin = 2.6°
Absorption correction: multi-scan (SADABS; Bruker, 2000)	h = −9→8
Tmin = 0.729, Tmax = 1.000	k = −22→22
6126 measured reflections	l = −18→17

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.028	H-atom parameters constrained
wR(F^2) = 0.068	w = 1/[σ^2(Fo^2) + (0.0286P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 1.04	(Δ/σ)max = 0.001
2931 reflections	Δρmax = 1.73 e Å^−3
244 parameters	Δρmin = −0.93 e Å^−3
2 restraints	Absolute structure: Flack (1983), 856 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: −0.037 (13)

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.

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 (Ų)

	x	y	z	Uiso*/Ueq
Pt1	0.39565 (2)	0.136006 (14)	0.162689 (18)	0.02282 (10)
Br1	0.19970 (16)	0.03626 (5)	0.11234 (8)	0.0369 (3)
Br2	0.5217 (2)	0.14016 (7)	0.02336 (11)	0.0415 (4)
N1	0.5395 (11)	0.2278 (4)	0.2077 (6)	0.030 (2)
N2	0.2978 (14)	0.1281 (4)	0.2842 (7)	0.021 (2)
C1	0.4929 (14)	0.2895 (5)	0.1628 (8)	0.035 (3)
H1	0.4181	0.2865	0.1081	0.042*
C2	0.5505 (16)	0.3567 (5)	0.1939 (10)	0.042 (3)
H2	0.5197	0.3997	0.1605	0.051*
C3	0.6514 (16)	0.3604 (5)	0.2727 (10)	0.044 (3)
H3	0.6870	0.4068	0.2970	0.052*
C4	0.7031 (14)	0.2986 (5)	0.3180 (8)	0.040 (3)
H4	0.7776	0.3013	0.3728	0.048*
C5	0.6453 (13)	0.2306 (5)	0.2829 (7)	0.029 (2)
C6	0.7103 (13)	0.1613 (5)	0.3294 (7)	0.029 (2)
C7	0.7024 (15)	0.1529 (7)	0.4178 (8)	0.043 (3)
H7	0.6555	0.1912	0.4503	0.052*
C8	0.7627 (16)	0.0885 (7)	0.4618 (9)	0.052 (3)
H8	0.7560	0.0824	0.5235	0.063*
C9	0.8311 (17)	0.0349 (7)	0.4137 (10)	0.056 (4)
H9	0.8734	−0.0087	0.4429	0.067*
C10	0.8406 (15)	0.0420 (6)	0.3247 (9)	0.046 (3)
H10	0.8896	0.0036	0.2931	0.055*
C11	0.7788 (14)	0.1051 (5)	0.2802 (8)	0.036 (3)
H11	0.7827	0.1102	0.2181	0.043*
C12	0.3481 (13)	0.0673 (4)	0.3308 (7)	0.027 (2)
H12	0.4130	0.0310	0.3039	0.032*
C13	0.3097 (13)	0.0563 (5)	0.4142 (7)	0.029 (2)
H13	0.3388	0.0115	0.4441	0.035*
C14	0.2264 (13)	0.1122 (5)	0.4554 (7)	0.033 (2)
H14	0.2045	0.1079	0.5156	0.040*
C15	0.1768 (13)	0.1735 (6)	0.4071 (7)	0.031 (2)
H15	0.1160	0.2115	0.4335	0.037*
C16	0.2145 (12)	0.1813 (5)	0.3183 (6)	0.023 (2)
C17	0.1496 (12)	0.2463 (4)	0.2664 (7)	0.024 (2)
C18	0.1739 (13)	0.3160 (5)	0.3025 (8)	0.035 (3)
H18	0.2335	0.3229	0.3606	0.042*
C19	0.1086 (17)	0.3755 (6)	0.2510 (11)	0.052 (4)
H19	0.1232	0.4236	0.2745	0.062*
C20	0.0250 (16)	0.3656 (6)	0.1683 (10)	0.046 (3)
H20	−0.0162	0.4068	0.1337	0.055*
C21	−0.0010 (15)	0.2976 (6)	0.1341 (8)	0.045 (3)
H21	−0.0622	0.2914	0.0762	0.054*
C22	0.0612 (12)	0.2370 (5)	0.1830 (7)	0.028 (2)
H22	0.0426	0.1892	0.1589	0.033*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Pt1	0.02761 (18)	0.01791 (14)	0.02340 (18)	−0.0005 (2)	0.00489 (12)	0.0005 (2)
Br1	0.0466 (7)	0.0262 (5)	0.0378 (6)	−0.0076 (5)	0.0053 (5)	−0.0108 (5)
Br2	0.0546 (10)	0.0435 (8)	0.0291 (8)	−0.0010 (6)	0.0162 (7)	0.0022 (6)
N1	0.032 (5)	0.026 (4)	0.035 (5)	−0.008 (4)	0.012 (4)	−0.002 (4)
N2	0.018 (5)	0.022 (4)	0.021 (6)	−0.005 (3)	−0.003 (4)	0.006 (4)
C1	0.040 (6)	0.019 (4)	0.048 (7)	0.001 (4)	0.009 (5)	0.008 (5)
C2	0.044 (7)	0.024 (5)	0.062 (9)	−0.010 (5)	0.019 (7)	0.001 (5)
C3	0.039 (7)	0.020 (5)	0.075 (10)	−0.013 (5)	0.020 (7)	−0.010 (6)
C4	0.038 (7)	0.035 (6)	0.047 (7)	−0.006 (5)	0.008 (5)	−0.009 (5)
C5	0.024 (5)	0.031 (5)	0.033 (6)	−0.008 (4)	0.005 (4)	−0.005 (5)
C6	0.027 (6)	0.025 (4)	0.033 (6)	−0.006 (4)	0.003 (4)	0.003 (4)
C7	0.026 (6)	0.067 (8)	0.034 (7)	−0.008 (6)	−0.003 (5)	−0.011 (6)
C8	0.046 (7)	0.067 (8)	0.042 (7)	−0.020 (7)	−0.002 (6)	0.008 (7)
C9	0.046 (8)	0.046 (7)	0.071 (10)	−0.009 (6)	−0.011 (7)	0.026 (7)
C10	0.040 (7)	0.032 (6)	0.061 (9)	−0.007 (5)	−0.012 (6)	−0.002 (6)
C11	0.040 (6)	0.028 (5)	0.039 (7)	−0.001 (5)	0.002 (5)	0.008 (5)
C12	0.032 (5)	0.017 (4)	0.031 (6)	−0.004 (4)	0.000 (4)	0.001 (4)
C13	0.029 (6)	0.025 (5)	0.033 (6)	−0.005 (4)	0.001 (5)	0.007 (4)
C14	0.033 (6)	0.041 (5)	0.026 (6)	−0.006 (5)	0.005 (5)	0.013 (5)
C15	0.027 (6)	0.037 (5)	0.029 (6)	−0.007 (4)	0.010 (4)	−0.007 (5)
C16	0.022 (5)	0.018 (4)	0.027 (5)	−0.004 (4)	0.001 (4)	0.004 (4)
C17	0.026 (5)	0.014 (4)	0.034 (6)	0.000 (4)	0.013 (4)	0.002 (4)
C18	0.026 (5)	0.026 (5)	0.053 (7)	−0.002 (4)	0.005 (5)	−0.002 (5)
C19	0.039 (7)	0.026 (5)	0.095 (12)	−0.005 (5)	0.026 (8)	−0.006 (7)
C20	0.038 (7)	0.027 (6)	0.076 (10)	0.003 (5)	0.018 (7)	0.021 (6)
C21	0.049 (7)	0.044 (7)	0.044 (7)	0.023 (6)	0.012 (6)	0.013 (6)
C22	0.024 (5)	0.029 (5)	0.030 (6)	0.002 (4)	0.005 (4)	0.001 (4)

Geometric parameters (Å, º)

Pt1—N1	2.075 (8)	C9—H9	0.9500
Pt1—N2	2.074 (10)	C10—C11	1.390 (14)
Pt1—Br1	2.4216 (11)	C10—H10	0.9500
Pt1—Br2	2.4258 (15)	C11—H11	0.9500
N1—C5	1.316 (13)	C12—C13	1.347 (14)
N1—C1	1.343 (12)	C12—H12	0.9500
N2—C16	1.303 (12)	C13—C14	1.391 (14)
N2—C12	1.346 (12)	C13—H13	0.9500
C1—C2	1.368 (14)	C14—C15	1.366 (14)
C1—H1	0.9500	C14—H14	0.9500
C2—C3	1.343 (19)	C15—C16	1.418 (13)
C2—H2	0.9500	C15—H15	0.9500
C3—C4	1.356 (16)	C16—C17	1.477 (12)
C3—H3	0.9500	C17—C22	1.370 (14)
C4—C5	1.400 (13)	C17—C18	1.389 (13)
C4—H4	0.9500	C18—C19	1.396 (17)
C5—C6	1.505 (13)	C18—H18	0.9500
C6—C7	1.358 (16)	C19—C20	1.348 (19)
C6—C11	1.406 (14)	C19—H19	0.9500
C7—C8	1.402 (17)	C20—C21	1.351 (16)
C7—H7	0.9500	C20—H20	0.9500
C8—C9	1.363 (17)	C21—C22	1.385 (13)
C8—H8	0.9500	C21—H21	0.9500
C9—C10	1.366 (18)	C22—H22	0.9500
N2—Pt1—N1	89.8 (3)	C9—C10—C11	120.1 (12)
N2—Pt1—Br1	87.3 (3)	C9—C10—H10	119.9
N1—Pt1—Br1	173.9 (2)	C11—C10—H10	119.9
N2—Pt1—Br2	176.9 (3)	C10—C11—C6	118.4 (10)
N1—Pt1—Br2	90.7 (2)	C10—C11—H11	120.8
Br1—Pt1—Br2	92.50 (5)	C6—C11—H11	120.8
C5—N1—C1	120.2 (9)	N2—C12—C13	122.4 (10)
C5—N1—Pt1	124.1 (7)	N2—C12—H12	118.8
C1—N1—Pt1	114.5 (7)	C13—C12—H12	118.8
C16—N2—C12	121.9 (10)	C12—C13—C14	118.4 (9)
C16—N2—Pt1	123.1 (7)	C12—C13—H13	120.8
C12—N2—Pt1	114.4 (7)	C14—C13—H13	120.8
N1—C1—C2	121.6 (12)	C15—C14—C13	118.2 (9)
N1—C1—H1	119.2	C15—C14—H14	120.9
C2—C1—H1	119.2	C13—C14—H14	120.9
C3—C2—C1	118.6 (11)	C14—C15—C16	121.1 (9)
C3—C2—H2	120.7	C14—C15—H15	119.4
C1—C2—H2	120.7	C16—C15—H15	119.4
C2—C3—C4	120.5 (10)	N2—C16—C15	117.8 (9)
C2—C3—H3	119.7	N2—C16—C17	122.5 (9)
C4—C3—H3	119.7	C15—C16—C17	119.5 (8)
C3—C4—C5	119.2 (11)	C22—C17—C18	120.3 (9)
C3—C4—H4	120.4	C22—C17—C16	119.1 (8)
C5—C4—H4	120.4	C18—C17—C16	120.5 (9)
N1—C5—C4	119.7 (10)	C17—C18—C19	118.2 (11)
N1—C5—C6	120.4 (9)	C17—C18—H18	120.9
C4—C5—C6	119.9 (9)	C19—C18—H18	120.9
C7—C6—C11	120.4 (10)	C20—C19—C18	120.8 (11)
C7—C6—C5	120.3 (9)	C20—C19—H19	119.6
C11—C6—C5	119.3 (9)	C18—C19—H19	119.6
C6—C7—C8	120.8 (11)	C19—C20—C21	120.7 (11)
C6—C7—H7	119.6	C19—C20—H20	119.6
C8—C7—H7	119.6	C21—C20—H20	119.6
C9—C8—C7	118.3 (12)	C20—C21—C22	120.4 (12)
C9—C8—H8	120.9	C20—C21—H21	119.8
C7—C8—H8	120.9	C22—C21—H21	119.8
C8—C9—C10	122.0 (12)	C17—C22—C21	119.5 (9)
C8—C9—H9	119.0	C17—C22—H22	120.3
C10—C9—H9	119.0	C21—C22—H22	120.3
N2—Pt1—N1—C5	51.4 (8)	C8—C9—C10—C11	−0.3 (19)
Br2—Pt1—N1—C5	−125.5 (7)	C9—C10—C11—C6	1.2 (16)
N2—Pt1—N1—C1	−116.7 (7)	C7—C6—C11—C10	−1.2 (15)
Br2—Pt1—N1—C1	66.4 (7)	C5—C6—C11—C10	179.0 (9)
N1—Pt1—N2—C16	55.9 (9)	C16—N2—C12—C13	2.7 (16)
Br1—Pt1—N2—C16	−118.6 (9)	Pt1—N2—C12—C13	174.1 (8)
N1—Pt1—N2—C12	−115.3 (8)	N2—C12—C13—C14	−4.8 (15)
Br1—Pt1—N2—C12	70.1 (8)	C12—C13—C14—C15	4.4 (15)
C5—N1—C1—C2	−1.1 (15)	C13—C14—C15—C16	−2.2 (14)
Pt1—N1—C1—C2	167.5 (8)	C12—N2—C16—C15	−0.2 (15)
N1—C1—C2—C3	−2.1 (16)	Pt1—N2—C16—C15	−170.9 (7)
C1—C2—C3—C4	3.6 (17)	C12—N2—C16—C17	−176.5 (9)
C2—C3—C4—C5	−2.0 (16)	Pt1—N2—C16—C17	12.9 (14)
C1—N1—C5—C4	2.7 (14)	C14—C15—C16—N2	0.1 (14)
Pt1—N1—C5—C4	−164.7 (7)	C14—C15—C16—C17	176.4 (9)
C1—N1—C5—C6	−174.7 (8)	N2—C16—C17—C22	45.9 (13)
Pt1—N1—C5—C6	17.9 (12)	C15—C16—C17—C22	−130.2 (9)
C3—C4—C5—N1	−1.2 (15)	N2—C16—C17—C18	−135.6 (10)
C3—C4—C5—C6	176.2 (9)	C15—C16—C17—C18	48.2 (13)
N1—C5—C6—C7	−132.2 (11)	C22—C17—C18—C19	−1.0 (14)
C4—C5—C6—C7	50.3 (13)	C16—C17—C18—C19	−179.4 (9)
N1—C5—C6—C11	47.6 (13)	C17—C18—C19—C20	−0.4 (16)
C4—C5—C6—C11	−129.9 (10)	C18—C19—C20—C21	1.5 (18)
C11—C6—C7—C8	0.2 (16)	C19—C20—C21—C22	−1.3 (17)
C5—C6—C7—C8	−180.0 (9)	C18—C17—C22—C21	1.2 (14)
C6—C7—C8—C9	0.7 (17)	C16—C17—C22—C21	179.7 (8)
C7—C8—C9—C10	−0.7 (18)	C20—C21—C22—C17	−0.1 (15)