The asymmetric unit of the title compound, (C
8H
12N)
2[PtCl
6], contains one independent protonated 2,4,6-trimethylpyridinium cation and one half of a centrosymmetric [PtCl
6]
2− anion. The Pt ion has an almost ideal octahedral coordination. In the crystal structure, intramolecular N—H

Cl and intermolecular C—H

Cl hydrogen bonds result in the formation of a supramolecular structure.
Supporting information
CCDC reference: 705958
Key indicators
- Single-crystal X-ray study
- T = 298 K
- Mean
(C-C) = 0.009 Å
- R factor = 0.037
- wR factor = 0.088
- Data-to-parameter ratio = 25.5
checkCIF/PLATON results
No syntax errors found
Alert level C
PLAT242_ALERT_2_C Check Low Ueq as Compared to Neighbors for Pt1
PLAT342_ALERT_3_C Low Bond Precision on C-C Bonds (x 1000) Ang ... 9
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ .... ?
PLAT154_ALERT_1_C The su's on the Cell Angles are Equal (x 10000) 800 Deg.
PLAT380_ALERT_4_C Check Incorrectly? Oriented X(sp2)-Methyl Moiety C1
PLAT380_ALERT_4_C Check Incorrectly? Oriented X(sp2)-Methyl Moiety C5
PLAT380_ALERT_4_C Check Incorrectly? Oriented X(sp2)-Methyl Moiety C8
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd. # 1
C8 H12 N
0 ALERT level A = In general: serious problem
0 ALERT level B = Potentially serious problem
8 ALERT level C = Check and explain
0 ALERT level G = General alerts; check
2 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
1 ALERT type 2 Indicator that the structure model may be wrong or deficient
1 ALERT type 3 Indicator that the structure quality may be low
4 ALERT type 4 Improvement, methodology, query or suggestion
0 ALERT type 5 Informative message, check
For the preparation of the title compound, (I), a solution of
2,4,6-trimethylpyridine (0.18 g, 1.48 mmol) in methanol (15 ml) was added to a
solution of H2PtCl6.6H2O, (0.38 g, 0.74 mmol) in acetonitrile (25 ml) and
the resulting yellow solution was stirred for 10 min at 313 K. Then, it was
left to evaporate slowly at room temperature. After one week, orange prismatic
crystals of (I) were isolated (yield; 0.35 g; 72.5%).
H atoms were positioned geometrically, with N—H = 0.86 Å (for NH) and
C—H = 0.93 and 0.96 Å for aromatic and methyl H, respectively, and
constrained to ride on their parent atoms with Uiso(H) = 1.2Ueq(C,N).
Data collection: SMART (Bruker, 1998); cell refinement: SMART (Bruker, 1998); data reduction: SAINT (Bruker, 1998); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).
Bis(2,4,6-trimethylpyridinium)hexachloridoplatinate(IV)
top
Crystal data top
(C8H12N)2[PtCl6] | Z = 1 |
Mr = 652.15 | F(000) = 314 |
Triclinic, P1 | Dx = 1.927 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 7.6302 (8) Å | Cell parameters from 1715 reflections |
b = 9.1328 (9) Å | θ = 3.0–29.1° |
c = 9.4599 (10) Å | µ = 6.96 mm−1 |
α = 99.201 (8)° | T = 298 K |
β = 109.683 (8)° | Prism, orange |
γ = 108.471 (8)° | 0.32 × 0.30 × 0.25 mm |
V = 561.87 (12) Å3 | |
Data collection top
Bruker SMART CCD area-detector diffractometer | 2962 independent reflections |
Radiation source: fine-focus sealed tube | 2952 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.099 |
ϕ and ω scans | θmax = 29.1°, θmin = 3.0° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1998) | h = −10→10 |
Tmin = 0.121, Tmax = 0.176 | k = −12→12 |
6510 measured reflections | l = −12→12 |
Refinement top
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.037 | H-atom parameters constrained |
wR(F2) = 0.088 | w = 1/[σ2(Fo2) + (0.0557P)2] where P = (Fo2 + 2Fc2)/3 |
S = 1.18 | (Δ/σ)max = 0.010 |
2962 reflections | Δρmax = 1.20 e Å−3 |
116 parameters | Δρmin = −1.44 e Å−3 |
0 restraints | Extinction correction: SHELXTL (Sheldrick, 1998), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.115 (6) |
Crystal data top
(C8H12N)2[PtCl6] | γ = 108.471 (8)° |
Mr = 652.15 | V = 561.87 (12) Å3 |
Triclinic, P1 | Z = 1 |
a = 7.6302 (8) Å | Mo Kα radiation |
b = 9.1328 (9) Å | µ = 6.96 mm−1 |
c = 9.4599 (10) Å | T = 298 K |
α = 99.201 (8)° | 0.32 × 0.30 × 0.25 mm |
β = 109.683 (8)° | |
Data collection top
Bruker SMART CCD area-detector diffractometer | 2962 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1998) | 2952 reflections with I > 2σ(I) |
Tmin = 0.121, Tmax = 0.176 | Rint = 0.099 |
6510 measured reflections | |
Refinement top
R[F2 > 2σ(F2)] = 0.037 | 0 restraints |
wR(F2) = 0.088 | H-atom parameters constrained |
S = 1.18 | Δρmax = 1.20 e Å−3 |
2962 reflections | Δρmin = −1.44 e Å−3 |
116 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 | Uiso*/Ueq | |
Pt1 | 0.0000 | 0.5000 | 0.0000 | 0.03163 (12) | |
Cl1 | 0.1751 (2) | 0.65180 (16) | 0.26337 (11) | 0.0496 (3) | |
Cl2 | −0.2671 (2) | 0.5772 (2) | −0.01978 (15) | 0.0522 (3) | |
Cl3 | −0.1501 (2) | 0.27660 (16) | 0.07023 (13) | 0.0486 (3) | |
N1 | −0.2844 (7) | 0.7163 (6) | 0.3174 (5) | 0.0473 (9) | |
H1D | −0.2918 | 0.6752 | 0.2261 | 0.057* | |
C1 | −0.2767 (12) | 0.4641 (8) | 0.3642 (6) | 0.0567 (14) | |
H1A | −0.1645 | 0.4737 | 0.3364 | 0.068* | |
H1B | −0.4017 | 0.3993 | 0.2738 | 0.068* | |
H1C | −0.2670 | 0.4137 | 0.4465 | 0.068* | |
C2 | −0.2721 (8) | 0.6278 (7) | 0.4197 (5) | 0.0448 (10) | |
C3 | −0.2540 (10) | 0.6948 (7) | 0.5686 (6) | 0.0496 (11) | |
H3 | −0.2448 | 0.6366 | 0.6410 | 0.059* | |
C4 | −0.2496 (10) | 0.8492 (8) | 0.6091 (6) | 0.0533 (12) | |
C5 | −0.2300 (17) | 0.9231 (11) | 0.7709 (8) | 0.077 (2) | |
H5A | −0.3464 | 0.9469 | 0.7620 | 0.092* | |
H5B | −0.1094 | 1.0211 | 0.8227 | 0.092* | |
H5C | −0.2215 | 0.8483 | 0.8310 | 0.092* | |
C6 | −0.2651 (10) | 0.9340 (7) | 0.4965 (7) | 0.0540 (12) | |
H6 | −0.2611 | 1.0380 | 0.5221 | 0.065* | |
C7 | −0.2858 (9) | 0.8639 (7) | 0.3499 (6) | 0.0493 (11) | |
C8 | −0.3106 (14) | 0.9436 (10) | 0.2211 (9) | 0.0687 (18) | |
H8A | −0.4370 | 0.8775 | 0.1325 | 0.082* | |
H8B | −0.2007 | 0.9562 | 0.1898 | 0.082* | |
H8C | −0.3100 | 1.0478 | 0.2589 | 0.082* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
Pt1 | 0.03766 (15) | 0.03245 (15) | 0.02614 (14) | 0.01452 (9) | 0.01484 (8) | 0.00745 (7) |
Cl1 | 0.0642 (7) | 0.0451 (6) | 0.0288 (4) | 0.0166 (5) | 0.0150 (4) | 0.0042 (3) |
Cl2 | 0.0546 (6) | 0.0726 (8) | 0.0457 (5) | 0.0397 (6) | 0.0252 (5) | 0.0200 (5) |
Cl3 | 0.0621 (7) | 0.0406 (6) | 0.0440 (5) | 0.0148 (5) | 0.0274 (5) | 0.0148 (4) |
N1 | 0.049 (2) | 0.052 (2) | 0.0380 (16) | 0.0178 (18) | 0.0172 (15) | 0.0113 (15) |
C1 | 0.076 (4) | 0.061 (3) | 0.045 (2) | 0.039 (3) | 0.028 (2) | 0.016 (2) |
C2 | 0.052 (2) | 0.047 (2) | 0.0385 (18) | 0.024 (2) | 0.0190 (17) | 0.0110 (16) |
C3 | 0.062 (3) | 0.052 (3) | 0.041 (2) | 0.028 (2) | 0.0239 (19) | 0.0121 (18) |
C4 | 0.062 (3) | 0.054 (3) | 0.044 (2) | 0.026 (2) | 0.023 (2) | 0.0060 (19) |
C5 | 0.116 (7) | 0.067 (5) | 0.052 (3) | 0.044 (5) | 0.039 (4) | 0.005 (3) |
C6 | 0.059 (3) | 0.042 (3) | 0.057 (3) | 0.018 (2) | 0.023 (2) | 0.012 (2) |
C7 | 0.046 (2) | 0.047 (3) | 0.049 (2) | 0.0134 (19) | 0.0164 (18) | 0.0172 (19) |
C8 | 0.074 (4) | 0.063 (4) | 0.067 (3) | 0.025 (3) | 0.024 (3) | 0.033 (3) |
Geometric parameters (Å, º) top
Pt1—Cl1 | 2.3225 (11) | C3—H3 | 0.9300 |
Pt1—Cl1i | 2.3225 (11) | C4—C6 | 1.409 (9) |
Pt1—Cl2 | 2.3199 (12) | C4—C5 | 1.507 (8) |
Pt1—Cl2i | 2.3199 (12) | C5—H5A | 0.9600 |
Pt1—Cl3i | 2.3197 (13) | C5—H5B | 0.9600 |
Pt1—Cl3 | 2.3197 (13) | C5—H5C | 0.9600 |
N1—H1D | 0.8600 | C6—C7 | 1.365 (9) |
C1—C2 | 1.488 (8) | C6—H6 | 0.9300 |
C1—H1A | 0.9600 | C7—N1 | 1.338 (8) |
C1—H1B | 0.9600 | C7—C8 | 1.505 (8) |
C1—H1C | 0.9600 | C8—H8A | 0.9600 |
C2—N1 | 1.355 (7) | C8—H8B | 0.9600 |
C2—C3 | 1.385 (6) | C8—H8C | 0.9600 |
C3—C4 | 1.388 (8) | | |
| | | |
Cl1—Pt1—Cl1i | 180.0 | C2—C3—C4 | 119.7 (5) |
Cl2—Pt1—Cl1i | 89.35 (5) | C2—C3—H3 | 120.2 |
Cl2i—Pt1—Cl1i | 90.65 (5) | C4—C3—H3 | 120.2 |
Cl2—Pt1—Cl1 | 90.65 (5) | C3—C4—C6 | 118.9 (5) |
Cl2—Pt1—Cl2i | 180.0 | C3—C4—C5 | 120.0 (6) |
Cl3—Pt1—Cl1 | 90.10 (5) | C6—C4—C5 | 121.1 (6) |
Cl3i—Pt1—Cl1i | 90.10 (5) | C4—C5—H5A | 109.5 |
Cl3—Pt1—Cl1i | 89.90 (5) | C4—C5—H5B | 109.5 |
Cl3—Pt1—Cl2 | 90.45 (6) | H5A—C5—H5B | 109.5 |
Cl3i—Pt1—Cl2i | 90.45 (6) | C4—C5—H5C | 109.5 |
Cl3—Pt1—Cl2i | 89.55 (6) | H5A—C5—H5C | 109.5 |
Cl3i—Pt1—Cl3 | 180.0 | H5B—C5—H5C | 109.5 |
C2—N1—H1D | 118.0 | C7—C6—C4 | 120.1 (5) |
C7—N1—C2 | 123.9 (5) | C7—C6—H6 | 119.9 |
C7—N1—H1D | 118.0 | C4—C6—H6 | 119.9 |
C2—C1—H1A | 109.5 | N1—C7—C6 | 118.9 (5) |
C2—C1—H1B | 109.5 | N1—C7—C8 | 117.6 (6) |
H1A—C1—H1B | 109.5 | C6—C7—C8 | 123.5 (6) |
C2—C1—H1C | 109.5 | C7—C8—H8A | 109.5 |
H1A—C1—H1C | 109.5 | C7—C8—H8B | 109.5 |
H1B—C1—H1C | 109.5 | H8A—C8—H8B | 109.5 |
N1—C2—C3 | 118.5 (5) | C7—C8—H8C | 109.5 |
N1—C2—C1 | 117.3 (4) | H8A—C8—H8C | 109.5 |
C3—C2—C1 | 124.2 (5) | H8B—C8—H8C | 109.5 |
| | | |
C1—C2—N1—C7 | 178.8 (6) | C3—C4—C6—C7 | 0.6 (10) |
C3—C2—N1—C7 | −1.9 (9) | C5—C4—C6—C7 | −179.0 (7) |
N1—C2—C3—C4 | 0.2 (9) | C4—C6—C7—N1 | −2.2 (10) |
C1—C2—C3—C4 | 179.5 (6) | C4—C6—C7—C8 | 177.8 (7) |
C2—C3—C4—C6 | 0.4 (10) | C6—C7—N1—C2 | 2.9 (9) |
C2—C3—C4—C5 | 180.0 (7) | C8—C7—N1—C2 | −177.0 (6) |
Symmetry code: (i) −x, −y+1, −z. |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1D···Cl2 | 0.86 | 2.45 | 3.301 (5) | 173 |
C1—H1C···Cl1ii | 0.96 | 2.81 | 3.743 (6) | 165 |
C8—H8A···Cl3iii | 0.96 | 2.80 | 3.731 (10) | 163 |
Symmetry codes: (ii) −x, −y+1, −z+1; (iii) −x−1, −y+1, −z. |
Experimental details
Crystal data |
Chemical formula | (C8H12N)2[PtCl6] |
Mr | 652.15 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 298 |
a, b, c (Å) | 7.6302 (8), 9.1328 (9), 9.4599 (10) |
α, β, γ (°) | 99.201 (8), 109.683 (8), 108.471 (8) |
V (Å3) | 561.87 (12) |
Z | 1 |
Radiation type | Mo Kα |
µ (mm−1) | 6.96 |
Crystal size (mm) | 0.32 × 0.30 × 0.25 |
|
Data collection |
Diffractometer | Bruker SMART CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1998) |
Tmin, Tmax | 0.121, 0.176 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 6510, 2962, 2952 |
Rint | 0.099 |
(sin θ/λ)max (Å−1) | 0.685 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.037, 0.088, 1.18 |
No. of reflections | 2962 |
No. of parameters | 116 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 1.20, −1.44 |
Selected geometric parameters (Å, º) topPt1—Cl1 | 2.3225 (11) | Pt1—Cl3 | 2.3197 (13) |
Pt1—Cl2 | 2.3199 (12) | | |
| | | |
Cl2—Pt1—Cl1i | 89.35 (5) | Cl3—Pt1—Cl1i | 89.90 (5) |
Cl2—Pt1—Cl1 | 90.65 (5) | Cl3—Pt1—Cl2 | 90.45 (6) |
Cl3—Pt1—Cl1 | 90.10 (5) | Cl3—Pt1—Cl2i | 89.55 (6) |
Symmetry code: (i) −x, −y+1, −z. |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1D···Cl2 | 0.86 | 2.45 | 3.301 (5) | 173.00 |
C1—H1C···Cl1ii | 0.96 | 2.81 | 3.743 (6) | 165.00 |
C8—H8A···Cl3iii | 0.96 | 2.80 | 3.731 (10) | 163.00 |
Symmetry codes: (ii) −x, −y+1, −z+1; (iii) −x−1, −y+1, −z. |
In recent years, there has been considerable interest in proton transfer systems and their structures (Rafizadeh et al., 2006; Yousefi, Amani & Khavasi, 2007; Abedi et al., 2008; Hojjat Kashani et al., 2008). Several proton transfer systems using 2,4,6-trimethylpyridine, with proton donor molecules, such as [2,4,6-tmpy.H]2[H2BTEC], (II), (Biradha & Zaworotko, 1998), {[2,4,6-tmpy.H]10[Er(H2O)Cl5]2[ErCl6]3Cl}, (III), (Hallfeldt & Urland, 2002), [2,4,6-tmpy.H][2-NBA], (IV) and [2,4,6-tmpy.H][3,5-NBA], (V), (Foces-Foces et al., 1999) [where 2,4,6-tmpy.H is 2,4,6-trimethylpyridinium, H2BTEC is dihydrogen-1,2,4,5-benzenetetracarboxylate, 2-NBA is 2-nitrobenzoate and 3,5-NBA is 3,5- nitrobenzoate] have been synthesized and characterized by single-crystal X-ray diffraction methods.
There are also several proton transfer systems using H2[PtCl6] with proton acceptor molecules, such as [HpyBr-3]2[PtCl6].2H2O, (VI), and [HpyI-3]2[PtCl6].2H2O, (VII),(Zordan & Brammer, 2004), [BMIM]2[PtCl6], (VIII), and [EMIM]2[PtCl6], (IX), (Hasan et al., 2001), {(DABCO)H2[PtCl6]}, (X), (Juan et al., 1998), {p-C6H4(CH2ImMe)2[PtCl6]}, (XI), (Li & Liu, 2003), [het][PtCl6].2H2O, (XII), (Hu et al., 2003), [9-MeGuaH]2[PtCl6].2H2O, (XIII), (Terzis & Mentzafos, 1983), [HpyCl-3]3[PtCl6]Cl, (XIV), (Zordan et al., 2005), [2,9-dmphen.H]2[PtCl6], (XV), (Yousefi, Ahmadi et al., 2007), [H2DA18C6][PtCl6].2H2O, (XVI), (Yousefi et al., 2007a), [2,6-dmpy.H]2[PtCl6], (XVII), (Amani et al., 2008) and [TBA]3[PtCl6]Cl, (XVIII), (Yousefi et al., 2007b) [where hpy is halo-pyridinium, BMIM+ is 1-n-butyl-3-methylimidazolium, EMIM+ is 1-ethyl-3-methyl- imidazolium, DABCO is 1,4-diazabicyclooctane, Im is imidazolium, het is 2-(α-hydroxyethyl)thiamine, 9-MeGuaH is 9-methylguaninium, 2,9-dmphen.H is 2,9-dimethyl-1,10-phenanthrolinium, H2DA18C6 is 1,10-Diazonia-18-crown-6, 2,6-dmpy.H is 2,6-dimethylpyridinium and TBA is tribenzylammonium] have been synthesized and characterized by single-crystal X-ray diffraction methods. We report herein the synthesis and crystal structure of the title compound, (I).
The asymmetric unit of (I), (Fig. 1) contains one independent protonated 2,4,6-trimethylpyridinium cation and one half of a centrosymmetric [PtCl6]2- anion. The Pt ion has an octahedral coordination. In cation, the bond lengths and angles are in good agreement with the corresponding values in (II) and (IV). In [PtCl6]2- anion, the Pt—Cl bond lengths and Cl—Pt—Cl bond angles (Table 1) are also within normal ranges, as in (XVI), (XVII) and (XVIII).
In the crystal structure (Fig. 2), intramolecular N—H···Cl and intermolecular C—H···Cl hydrogen bonds (Table 2) result in the formation of a supramolecular structure, in which they may be effective in the stabilization of the structure.