Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807048428/lh2492sup1.cif | |
Rietveld powder data file (CIF format) https://doi.org/10.1107/S1600536807048428/lh2492Isup2.rtv |
CCDC reference: 667130
Key indicators
- Powder X-ray study
- T = 293 K
- Mean (N-C) = 0.019 Å
- R factor = 0.000
- wR factor = 0.000
- Data-to-parameter ratio = 26.3
checkCIF/PLATON results
No syntax errors found
Alert level C REFI023_ALERT_1_C _refine_diff_density_max is missing Maximum value of final difference map (e A-3). The following tests will not be performed DIFMN_01,DIFMX_01,DIFMX_02 REFI024_ALERT_1_C _refine_diff_density_min is missing Minimum value of final difference map (e A-3). The following tests will not be performed DIFMN_01,DIFMN_02,DIFMN_03 SHFSU01_ALERT_2_C The absolute value of parameter shift to su ratio > 0.05 Absolute value of the parameter shift to su ratio given 0.100 Additional refinement cycles may be required. PLAT080_ALERT_2_C Maximum Shift/Error ............................ 0.10 PLAT164_ALERT_4_C Nr. of Refined C-H H-Atoms in Heavy-At Struct... 6 PLAT180_ALERT_3_C Check Cell Rounding: # of Values Ending with 0 = 3 PLAT745_ALERT_1_C D-H Calc 0.900(19), Rep 0.90000 ...... Missing su N1 -H1A 1.555 1.555 PLAT745_ALERT_1_C D-H Calc 0.900(14), Rep 0.90000 ...... Missing su N1 -H1B 1.555 1.555 PLAT745_ALERT_1_C D-H Calc 0.900(13), Rep 0.90000 ...... Missing su N2 -H2A 1.555 1.555 PLAT745_ALERT_1_C D-H Calc 0.900(13), Rep 0.90000 ...... Missing su N2 -H2B 1.555 1.555 PLAT746_ALERT_1_C H...A Calc 2.797(12), Rep 2.80000 ...... Missing su H1A -CL2 1.555 3.657 PLAT746_ALERT_1_C H...A Calc 2.477(10), Rep 2.48000 ...... Missing su H1B -CL2 1.555 1.554 PLAT746_ALERT_1_C H...A Calc 2.696(9), Rep 2.70000 ...... Missing su H2A -CL2 1.555 1.554 PLAT746_ALERT_1_C H...A Calc 2.829(16), Rep 2.83000 ...... Missing su H2B -CL2 1.555 3.757 PLAT764_ALERT_4_C Overcomplete CIF Bond List Detected (Rep/Expd) . 1.17 Ratio
Alert level G PLAT794_ALERT_5_G Check Predicted Bond Valency for Pt1 (2) 1.91
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 15 ALERT level C = Check and explain 1 ALERT level G = General alerts; check 10 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 2 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 2 ALERT type 4 Improvement, methodology, query or suggestion 1 ALERT type 5 Informative message, check
For the preparation of cis-[Pt(CH3NH2)2Cl2] the salt K2PtCl4 in amount of 4 g was dissolved in 20 ml of water. Then 3 g of CH3NH2·HCl and 4 g CH3COOK were added to the solution. The mixture was slightly heated until solution became colorless and then cooled down to room temperature. The solution was kept during 3 h at room temperature, pH was adjusted close to 8 by KOH solution. The light yellow precipitate was filtered, washed and dried. Elemental chemical analysis confirmed the chemical formula of the substance.
The structure determination was carried out by the X-ray powder diffraction technique. The experimental data were collected using DRON-4 automatic diffractometer, equipped with a secondary flat graphite monochromator in conjunction with a scintillation detector. Cu Kα radiation was used (λ1 = 1.54056 Å, λ2 = 1.54439 Å). The sample was prepared by top-loading the standard quartz sample holder with cutting the excess of well grained substance. The diffraction pattern was scanned with the step of 0.02° 2θ and counting time of 5 sec./step in the most informative angular range from 9° to 115% 2θ at room temperature. Corundum was used as the external standard. The powder pattern of cis-bis(methylamine) dichloro platimun(II) is presented in Fig. 1. X-ray powder diffraction data have been deposited in JCPDS-ICDD PDF2 database (ICDD, 2005). Cell parameters were obtained from d-spaces by indexing and refining using programs described in (Visser, 1969; Kirik et al., 1979). The space group was determined from the analysis of systematic absences. The structural investigations were carried out using a full-profile structure analysis package based on a modified version of the Rietveld refinement program DBWS-9006PC (Wiles & Young, 1981; Kirik, 1985). The intensities of 50 reflections were estimated from the powder pattern by means of the full-profile fitting procedure (Le Bail et al., 1988) and used in the Patterson synthesis. Atoms of Pt and Cl were located directly from the Patterson map. Positions of light atoms N and C were defined from a difference Fourier synthesis. The final refinement was carried out by Rietveld method (Rietveld, 1969; Wiles & Young, 1981). H-atoms were not located, but they were included in the refined structure models and rigidly connected to their C and N atoms with N—H = 0.90 and C—H = 0.96 Å and Uiso(H) = 0.152 Å2.
The title complex, cis-[Pt(CH3NH2)2Cl2], has attracted attention due to its biological activity especially in connection with cancer chemotherapy (Clere & Hoechele, 1973; Clere, 1974). Reports on cis-[Pt(CH3NH2)2Cl2] can be found in the literature as early as the nineteen fifties (Grinberg & Gildengershel, 1951; Gildengershel, 1956). X-ray diffraction data were published by Watt et al. (1967) and a single-crystal structure was determined by Wimmer et al. (1988). This group found the existence of two forms A and B. Concisely the form A is build from molecules cis-[Pt(CH3NH2)2Cl2] in the conformation where both methyl groups lie on the same side of the plane delimited by the two chloride and the two nitrogen atoms (motif A). The form B consists of molecules of two possible conformations: above mentioned motif A and a motif B where methyl groups are on the both side of "platinum" plane. Unfortunately the publication (Wimmer et al., 1988) does not present the 3-D coordinates of the structures, and that hinders the detailed analysis of reasons for the different types of conformations. Here we present the results of crystal structure determination of cis-[Pt(CH3NH2)2Cl2] in form A obtained applying another synthetic approach without using AgI as it was done by Wimmer et al. (1988) following Dhara (1970). Another important feature follows from application of the X-ray powder technique that allows ascribing the structure to bulk sample of the substance.
The crystal structure of cis-bis(metylamine) dichloro platimun(II) consists of discrete molecules. The geometry of the molecule is presented in Fig. 2. The Pt atom has slightly distorted square-planar coordination enviroment consisting of two N and two Cl atoms. The torsion angle Cl2—Cl1—N1—N2 = 177.5°. The distances Pt1—N1, Pt1—N2, Pt1—Cl1 and Pt1—Cl2 are 2.083 (14) Å, 2.088 (12) Å, 2.303 (5) Å and 2.343 (4) Å respectively and these correspond well to known in literature values (Arpalahti et al., 1988; Wimmer et al., 1988; Kirik et al., 1996; Wells, 1984; Allen, 2002; ICSD, 2007). Metylamine as a ligand does not induce essential distortions of the molecule. The N1—Pt1—N2 angle is 90.0 (4)°. The N···Cl contacts in the molecule are of 3.081 (16) Å and 3.095 (15) Å. Methyl-groups are oriented to one side of the PtN2Cl2plane. Molecules conjugate in pairs due to (Cl···H—N) intermolecular bounding with centrosymmetric orientation respectively each other. N···Cl contacts between nearest molecules are of 3.296 (16) Å and 3.462 (16) Å. The shortest (Pt···Pt) distance in pairs equals to 3.372 (2) Å. The pairs comprise double layers stretched along (ac)-plane with methylamine ligands protruding from layers forming organic interlayers (Fig. 3). This type of packing is also typical for other methylamine containing compound (Kirik & Starkov, 2007).
The title compound was previously reported by Watt et al. (1967) and Wimmer et al. (1988). For related compounds, see: Arpalahti et al. (1988); Clere (1974); Clere & Hoechele (1973); Dhara (1970); Gildengershel (1956); Grinberg & Gildengershel (1951); Kirik & Starkov (2007); Kirik et al. (1996); Wells (1984). Searches were conducted using the Cambridge Structural Database (Version?; Allen, 2002) and the Inorganic Crystal Structure Database (Version 2007–1; ICSD, 2007). X-ray powder diffraction data have been deposited in the JCPDS-ICDD PDF-2 database (ICDD, 2005). For analysis techniques, see: Kirik (1985); Kirik et al. (1979); Le Bail et al. (1988); Rietveld (1969); Visser (1969); Wiles & Young (1981). [Original long list of references has been rearranged to make it more informative. Please check.]
Data collection: DRON-4 data collection software; cell refinement: POWDER (Kirik et al., 1979); data reduction: DRON-4 data collection software; program(s) used to solve structure: modified DBWM (Wiles & Young, 1981); program(s) used to refine structure: modified DBWM (Wiles & Young, 1981); molecular graphics: SHELXTL (Siemens, 1989); software used to prepare material for publication: SHELXTL (Siemens, 1989).
[PtCl2(CH5N)2] | F(000) = 592.0 |
Mr = 328.10 | Final cell parameters are obtained from the Rietveld refinement |
Monoclinic, P21/n | Dx = 2.982 Mg m−3 |
Hall symbol: -P 2yn | Cu Kα radiation |
a = 7.4512 (1) Å | T = 293 K |
b = 15.7995 (2) Å | Particle morphology: thin powder |
c = 6.3015 (1) Å | yellow |
β = 99.930 (3)° | circular flate plate, 20.0 × 20.0 mm |
V = 730.73 (2) Å3 | Specimen preparation: Prepared at 293 K and 101 kPa, cooled at 0 K min−1 |
Z = 4 |
DRON-4 powder diffractometer | Specimen mounting: packed powder pellet |
Radiation source: conventional sealed tube | Data collection mode: reflection |
Graphite monochromator | 2θmin = 9.0°, 2θmax = 115.0°, 2θstep = 0.02° |
Refinement on F2 | Profile function: Pearson VII (Wiles & Young, 1981 |
Least-squares matrix: full | 38 parameters |
Rp = 0.059 | 0 restraints |
Rwp = 0.080 | 0 constraints |
Rexp = 0.056 | H-atom parameters not refined |
RBragg = 0.035 | Weighting scheme based on measured s.u.'s |
R(F2) = 0.036 | (Δ/σ)max = 0.1 |
Excluded region(s): none | Preferred orientation correction: March–Dollase correction (Dollase, 1986) |
[PtCl2(CH5N)2] | β = 99.930 (3)° |
Mr = 328.10 | V = 730.73 (2) Å3 |
Monoclinic, P21/n | Z = 4 |
a = 7.4512 (1) Å | Cu Kα radiation |
b = 15.7995 (2) Å | T = 293 K |
c = 6.3015 (1) Å | circular flate plate, 20.0 × 20.0 mm |
DRON-4 powder diffractometer | Data collection mode: reflection |
Specimen mounting: packed powder pellet | 2θmin = 9.0°, 2θmax = 115.0°, 2θstep = 0.02° |
Rp = 0.059 | 38 parameters |
Rwp = 0.080 | 0 restraints |
Rexp = 0.056 | H-atom parameters not refined |
RBragg = 0.035 | (Δ/σ)max = 0.1 |
R(F2) = 0.036 |
x | y | z | Uiso*/Ueq | ||
Pt1 | 0.8950 (2) | 0.0946 (1) | 0.9978 (2) | 0.0121* | |
Cl1 | 1.1570 (6) | 0.1223 (4) | 1.2400 (6) | 0.0197* | |
Cl2 | 0.7322 (5) | 0.0594 (3) | 1.2720 (6) | 0.0186* | |
N1 | 0.6610 (13) | 0.0672 (10) | 0.7760 (14) | 0.0234* | |
H1A | 0.6022 (13) | 0.0245 (10) | 0.8290 (14) | 0.152* | |
H1B | 0.6954 (13) | 0.0484 (10) | 0.6543 (14) | 0.152* | |
C2 | 1.0380 (12) | 0.2250 (11) | 0.7050 (12) | 0.0226* | |
H2C | 1.1018 (12) | 0.2353 (11) | 0.5875 (12) | 0.152* | |
H2D | 0.9164 (12) | 0.2470 (11) | 0.6698 (12) | 0.152* | |
H2E | 1.1007 (12) | 0.2525 (11) | 0.8324 (12) | 0.152* | |
N2 | 1.0300 (11) | 0.1280 (10) | 0.7460 (10) | 0.0231* | |
H2A | 0.9738 (11) | 0.1028 (10) | 0.6245 (10) | 0.152* | |
H2B | 1.1446 (11) | 0.1078 (10) | 0.7751 (10) | 0.152* | |
C1 | 0.5240 (12) | 0.1410 (9) | 0.7160 (10) | 0.0237* | |
H1C | 0.4220 (12) | 0.1214 (9) | 0.6134 (10) | 0.152* | |
H1D | 0.4823 (12) | 0.1606 (9) | 0.8432 (10) | 0.152* | |
H1E | 0.5831 (12) | 0.1865 (9) | 0.6543 (10) | 0.152* |
Pt1—Cl1 | 2.303 (5) | Cl2—H2Bi | 2.829 (16) |
Pt1—Cl2 | 2.343 (4) | N1—H1A | 0.90 (1) |
Pt1—N1 | 2.083 (14) | N1—H1B | 0.90 (1) |
Pt1—N2 | 2.088 (12) | N2—H2A | 0.90 (1) |
N1—C1 | 1.553 (18) | N2—H2B | 0.90 (1) |
N2—C2 | 1.56 (3) | C1—H1C | 0.96 (1) |
Pt1—Pt1i | 3.372 (2) | C1—H1D | 0.96 (1) |
Cl1—H2Aii | 2.995 (4) | C1—H1E | 0.96 (1) |
Cl1—H1Ai | 3.010 (15) | C2—H2C | 0.96 (1) |
Cl1—H2B | 2.924 (4) | C2—H2D | 0.96 (1) |
Cl1—H1Bi | 2.945 (16) | C2—H2E | 0.96 (1) |
Cl1—H2B | 2.924 (4) | ||
Cl1—Pt1—Cl2 | 92.5 (2) | Pt1—N2—H2A | 108.6 (6) |
Cl1—Pt1—N2 | 89.5 (2) | Pt1—N2—H2B | 108.6 (6) |
Cl2—Pt1—N1 | 88.0 (2) | N1—C1—H1C | 109.4 (14) |
N1—Pt1—N2 | 90.0 (4) | N1—C1—H1D | 109.4 (6) |
Pt1—N1—C1 | 116.5 (6) | N1—C1—H1E | 109.4 (6) |
Pt1—N2—C2 | 114.3 (6) | N2—C2—H2C | 109.4 (16) |
Pt1—N1—H1A | 108.1 (6) | N2—C2—H2D | 109.4 (15) |
Pt1—N1—H1B | 108.1 (6) | N2—C2—H2E | 109.4 (14) |
Symmetry codes: (i) −x+2, −y, −z+2; (ii) x, y, z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···Cl2iii | 0.90 | 2.80 | 3.517 (13) | 138 |
N1—H1B···Cl2iv | 0.90 | 2.48 | 3.311 (10) | 154 |
N2—H2A···Cl2iv | 0.90 | 2.70 | 3.569 (9) | 163 |
N2—H2B···Cl2i | 0.90 | 2.83 | 3.462 (15) | 128 |
Symmetry codes: (i) −x+2, −y, −z+2; (iii) −x+1, −y, −z+2; (iv) x, y, z−1. |
Experimental details
Crystal data | |
Chemical formula | [PtCl2(CH5N)2] |
Mr | 328.10 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 293 |
a, b, c (Å) | 7.4512 (1), 15.7995 (2), 6.3015 (1) |
β (°) | 99.930 (3) |
V (Å3) | 730.73 (2) |
Z | 4 |
Radiation type | Cu Kα |
Specimen shape, size (mm) | Circular flate plate, 20.0 × 20.0 |
Data collection | |
Diffractometer | DRON-4 powder diffractometer |
Specimen mounting | Packed powder pellet |
Data collection mode | Reflection |
Scan method | ? |
2θ values (°) | 2θmin = 9.0 2θmax = 115.0 2θstep = 0.02 |
Refinement | |
R factors and goodness of fit | Rp = 0.059, Rwp = 0.080, Rexp = 0.056, RBragg = 0.035, R(F2) = 0.036, χ2 = 2.045 |
No. of parameters | 38 |
H-atom treatment | H-atom parameters not refined |
(Δ/σ)max | 0.1 |
Computer programs: DRON-4 data collection software, POWDER (Kirik et al., 1979), modified DBWM (Wiles & Young, 1981), SHELXTL (Siemens, 1989).
Pt1—Cl1 | 2.303 (5) | Pt1—N1 | 2.083 (14) |
Pt1—Cl2 | 2.343 (4) | Pt1—N2 | 2.088 (12) |
Cl1—Pt1—Cl2 | 92.5 (2) | Cl2—Pt1—N1 | 88.0 (2) |
Cl1—Pt1—N2 | 89.5 (2) | N1—Pt1—N2 | 90.0 (4) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···Cl2i | 0.90 | 2.80 | 3.517 (13) | 138 |
N1—H1B···Cl2ii | 0.90 | 2.48 | 3.311 (10) | 154 |
N2—H2A···Cl2ii | 0.90 | 2.70 | 3.569 (9) | 163 |
N2—H2B···Cl2iii | 0.90 | 2.83 | 3.462 (15) | 128 |
Symmetry codes: (i) −x+1, −y, −z+2; (ii) x, y, z−1; (iii) −x+2, −y, −z+2. |
The title complex, cis-[Pt(CH3NH2)2Cl2], has attracted attention due to its biological activity especially in connection with cancer chemotherapy (Clere & Hoechele, 1973; Clere, 1974). Reports on cis-[Pt(CH3NH2)2Cl2] can be found in the literature as early as the nineteen fifties (Grinberg & Gildengershel, 1951; Gildengershel, 1956). X-ray diffraction data were published by Watt et al. (1967) and a single-crystal structure was determined by Wimmer et al. (1988). This group found the existence of two forms A and B. Concisely the form A is build from molecules cis-[Pt(CH3NH2)2Cl2] in the conformation where both methyl groups lie on the same side of the plane delimited by the two chloride and the two nitrogen atoms (motif A). The form B consists of molecules of two possible conformations: above mentioned motif A and a motif B where methyl groups are on the both side of "platinum" plane. Unfortunately the publication (Wimmer et al., 1988) does not present the 3-D coordinates of the structures, and that hinders the detailed analysis of reasons for the different types of conformations. Here we present the results of crystal structure determination of cis-[Pt(CH3NH2)2Cl2] in form A obtained applying another synthetic approach without using AgI as it was done by Wimmer et al. (1988) following Dhara (1970). Another important feature follows from application of the X-ray powder technique that allows ascribing the structure to bulk sample of the substance.
The crystal structure of cis-bis(metylamine) dichloro platimun(II) consists of discrete molecules. The geometry of the molecule is presented in Fig. 2. The Pt atom has slightly distorted square-planar coordination enviroment consisting of two N and two Cl atoms. The torsion angle Cl2—Cl1—N1—N2 = 177.5°. The distances Pt1—N1, Pt1—N2, Pt1—Cl1 and Pt1—Cl2 are 2.083 (14) Å, 2.088 (12) Å, 2.303 (5) Å and 2.343 (4) Å respectively and these correspond well to known in literature values (Arpalahti et al., 1988; Wimmer et al., 1988; Kirik et al., 1996; Wells, 1984; Allen, 2002; ICSD, 2007). Metylamine as a ligand does not induce essential distortions of the molecule. The N1—Pt1—N2 angle is 90.0 (4)°. The N···Cl contacts in the molecule are of 3.081 (16) Å and 3.095 (15) Å. Methyl-groups are oriented to one side of the PtN2Cl2plane. Molecules conjugate in pairs due to (Cl···H—N) intermolecular bounding with centrosymmetric orientation respectively each other. N···Cl contacts between nearest molecules are of 3.296 (16) Å and 3.462 (16) Å. The shortest (Pt···Pt) distance in pairs equals to 3.372 (2) Å. The pairs comprise double layers stretched along (ac)-plane with methylamine ligands protruding from layers forming organic interlayers (Fig. 3). This type of packing is also typical for other methylamine containing compound (Kirik & Starkov, 2007).