supplementary materials


sj5329 scheme

Acta Cryst. (2013). E69, m446-m447    [ doi:10.1107/S1600536813017376 ]

Dichloridobis[3-(4-chlorophenyl)-2,N,N-trimethyl-2,3-dihydro-1,2,4-oxadiazole-5-amine-[kappa]N4]platinum(II)-4-chlorobenzaldehyde (1/1)

A. S. Kritchenkov, V. V. Gurzhiy, N. A. Bokach and V. A. Kalibabchuk

Abstract top

In the title 1:1 co-crystal, [PtCl2(C11H14ClN3O)2]·C7H5ClO, the coordination polyhedron of the PtII atom is slightly distorted square-planar with the chloride and 2,3-dihydro-1,2,4-oxadiazole ligands mutually trans, as the Pt atom lies on an inversion center. The 4-chlorobenzaldehyde molecules are statistically disordered about an inversion centre with equal occupancies for the two positions. The PtII complex forms a three-dimensional structure through C-H...Cl and weaker C-H...O interactions with the 4-chlorobenzaldehyde molecule.

Comment top

In the past decade, a great attention has been paid to metal-mediated cycloaddition (CA) of various dipoles to nitriles. Indeed, the activation of nitrile substrates by a metal center often results in promotion of CAs, which are not feasible in the so-called pure organic chemistry. In addition, metal-mediated CA represents an efficient route to free and/or coordinated heterocycles that could be either difficult to obtain or even inaccessible via metal-free protocols (Bokach et al., 2011; Bokach & Kukushkin, 2006). Furthermore, an interest in platinum complexes with 2,3-dihydro-1,2,4-oxadiazole as a ligand is caused by their potential applications in medicine.

While 2,3-dihydro-1,2,4-oxadiazoles are known, examples of 5-dialkylamino-2,3-dihydro-1,2,4-oxadiazoles and, in particular, their metal complexes are still rare. Therefore, the synthesis of new complexes with 5-dialkylamino-2,3-dihydro-1,2,4-oxadiazole ligands and studies of their properties represent important tasks. As an amplification of our investigations of metal-mediated CA (Bokach et al., 2011; Kuznetsov & Kukushkin, 2006) and the reactivity of metal-bound dialkylcyanamides (Kritchenkov et al., 2011; Bokach et al., 2003; Gushchin et al., 2008), we have synthesized and characterized the title co-crystal and report its molecular and crystal structure here.

In 1, the complex molecule contains one crystallographically independent Pt atom that lies on an inversion center and is coordinated by two equivalent Cl- anions and two N atoms (Fig. 1) of the heterocyclic ligands each of which are mutually trans. The Pt(1)–N(1) bond length is typical for (imine)PtII species (Allen et al., 1987). The N(4)–C(5) (1.301 (4) Å) distance is characteristic for the N=C double bond (Fritsky et al., 2006; Penkova et al., 2009), while the N(4)–C(3) and N(2)–C(3) (1.476 (4) and 1.474 (4), respectively) are specific for the N–C single bonds (Allen et al., 1987). Both asymmetric C(3) atoms in the heterocyclic ligands exhibit the same configuration (RR/SS). The p-chlorobenzaldehyde molecules are statistically disordered about an inversion centre with equal occupancies for the two half-occupied positions.

The platinum complexes are arranged in layers parallel to the (001) plane (Fig. 2). The p-chlorobenzaldehyde molecules occupy sites in between the layers of platinum(II) complexes.

Related literature top

For the synthesis of platinum complexes with 2,3-dihydro-1,2,4-oxadiazole ligands, see: Bokach et al. (2011); Kritchenkov et al. (2011). For related structures, see: Bokach et al. (2003, 2011); Kritchenkov et al. (2011); Bokach & Kukushkin (2006); Gushchin et al. (2008); Kuznetsov & Kukushkin (2006); Fritsky et al. (2006); Penkova et al. (2009). For standard bond lengths, see: see: Allen et al. (1987).

Experimental top

The platinum complex was synthesized by a cycloaddition reaction between the complex trans-[PtCl2(NCNMe2)2] and the nitrone p-ClC6H4C(H)=N(O)Me as described previously (Kritchenkov et al., 2011). Crystals of 1 were obtained from the reaction mixture by slow evaporation of the solvent (dichloromethane) at room temperature; p-chlorobenzaldehyde was generated in the reaction mixture by hydration of the nitrone in the undried solvent.

Refinement top

The carbon- and nitrogen-bound H atoms were placed in calculated positions and were included in the refinement in the riding model approximation, with Uiso(H) set to 1.5Ueq(C) and C–H 0.96 Å for the methyl groups, 1.2Ueq(C) and C–H 0.98 Å for the tertiary CH groups, 1.2Ueq(C) and C–H 0.93 Å for the carbon atoms of the benzene rings and aldehyde group, and 1.2Ueq(N) and N–H 0.91 Å for the tertiary NH groups.

Computing details top

Data collection: CrysAlis PRO (Agilent, 2012); cell refinement: CrysAlis PRO (Agilent, 2012); data reduction: CrysAlis PRO (Agilent, 2012); program(s) used to solve structure: SIR2004 (Burla et al., 2005); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. A view of the C22H30Cl4N6O2Pt complex in the structure of 1. Thermal ellipsoids are drawn at the 50% probability level. Pt atoms are blue, chlorine, carbon, nitrogen, and oxygen atoms are green, grey, pale blue, and red, respectively. Primed atoms are related to unprimed atoms by the symmetry operation -x+1, -y+1 -z.
[Figure 2] Fig. 2. Crystal structure of the C22H30Cl4N6O2Pt.C7H5OCl associate, projection to the (010). Pt atoms are blue, chlorine, carbon,nitrogen, and oxygen atoms are green, grey, pale blue, and red, respectively.
Dichloridobis[3-(4-chlorophenyl)-2,N,N-trimethyl-2,3-dihydro-1,2,4-oxadiazole-5-amine-κN4]platinum(II)–4-chlorobenzaldehyde (1/1) top
Crystal data top
[PtCl2(C11H15ClN3O)2]·C7H5ClOZ = 1
Mr = 887.97F(000) = 438
Triclinic, P1Dx = 1.737 Mg m3
a = 8.46436 (18) ÅMo Kα radiation, λ = 0.71073 Å
b = 9.38481 (19) ÅCell parameters from 9801 reflections
c = 11.4373 (3) Åθ = 2.5–31.7°
α = 101.0381 (18)°µ = 4.57 mm1
β = 104.9553 (19)°T = 100 K
γ = 96.3847 (17)°Prism, colourless
V = 849.07 (3) Å30.17 × 0.11 × 0.09 mm
Data collection top
Agilent Xcalibur Eos
diffractometer
3892 independent reflections
Radiation source: Enhance (Mo) X-ray Source3888 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.036
Detector resolution: 16.2096 pixels mm-1θmax = 27.5°, θmin = 2.5°
ω scansh = 1010
Absorption correction: multi-scan
(DENZO/SCALEPACK; Otwinowski & Minor, 1997)
k = 1212
Tmin = 0.933, Tmax = 1.000l = 1414
13908 measured reflections
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)] = 0.022Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.054H-atom parameters constrained
S = 1.06 w = 1/[σ2(Fo2) + (0.0326P)2]
where P = (Fo2 + 2Fc2)/3
3892 reflections(Δ/σ)max < 0.001
211 parametersΔρmax = 1.63 e Å3
0 restraintsΔρmin = 1.21 e Å3
Crystal data top
[PtCl2(C11H15ClN3O)2]·C7H5ClOγ = 96.3847 (17)°
Mr = 887.97V = 849.07 (3) Å3
Triclinic, P1Z = 1
a = 8.46436 (18) ÅMo Kα radiation
b = 9.38481 (19) ŵ = 4.57 mm1
c = 11.4373 (3) ÅT = 100 K
α = 101.0381 (18)°0.17 × 0.11 × 0.09 mm
β = 104.9553 (19)°
Data collection top
Agilent Xcalibur Eos
diffractometer
3892 independent reflections
Absorption correction: multi-scan
(DENZO/SCALEPACK; Otwinowski & Minor, 1997)
3888 reflections with I > 2σ(I)
Tmin = 0.933, Tmax = 1.000Rint = 0.036
13908 measured reflectionsθmax = 27.5°
Refinement top
R[F2 > 2σ(F2)] = 0.022H-atom parameters constrained
wR(F2) = 0.054Δρmax = 1.63 e Å3
S = 1.06Δρmin = 1.21 e Å3
3892 reflectionsAbsolute structure: ?
211 parametersAbsolute structure parameter: ?
0 restraintsRogers parameter: ?
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Refinement. Refinement of F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > 2sigma(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ 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*/UeqOcc. (<1)
Pt10.50000.50000.00000.01562 (5)
O10.8747 (3)0.5755 (3)0.34126 (19)0.0321 (5)
N20.9212 (3)0.4486 (3)0.2650 (2)0.0290 (6)
H20.99720.47860.22730.035*
C30.7596 (4)0.3810 (3)0.1742 (3)0.0243 (6)
H30.69360.32030.21120.029*
N40.6856 (3)0.5130 (3)0.1552 (2)0.0209 (5)
C50.7499 (4)0.6134 (3)0.2577 (3)0.0240 (6)
N60.7135 (3)0.7450 (3)0.2956 (2)0.0281 (6)
C70.5711 (4)0.8001 (4)0.2268 (3)0.0334 (7)
H7A0.60500.85520.17230.050*
H7B0.52930.86270.28430.050*
H7C0.48560.71860.17880.050*
C80.8131 (5)0.8425 (4)0.4142 (3)0.0451 (10)
H8A0.76420.82720.47880.068*
H8B0.81630.94320.40770.068*
H8C0.92390.82090.43380.068*
C90.9849 (5)0.3574 (4)0.3496 (3)0.0452 (10)
H9A1.08130.41290.41340.068*
H9B1.01420.27210.30450.068*
H9C0.90120.32720.38690.068*
C100.7869 (4)0.2884 (3)0.0606 (3)0.0230 (6)
C110.7575 (5)0.1367 (4)0.0400 (3)0.0342 (7)
H110.71560.09190.09410.041*
C120.7907 (5)0.0506 (4)0.0617 (3)0.0434 (9)
H120.77050.05160.07650.052*
C130.8532 (5)0.1191 (4)0.1391 (3)0.0365 (8)
Cl140.89823 (18)0.01398 (12)0.26699 (9)0.0619 (3)
C150.8828 (4)0.2708 (4)0.1219 (3)0.0306 (7)
H150.92430.31500.17640.037*
C160.8483 (4)0.3547 (3)0.0206 (3)0.0257 (6)
H160.86670.45690.00700.031*
Cl170.34015 (9)0.32493 (9)0.05713 (7)0.03003 (16)
C190.5885 (5)0.4816 (5)0.6159 (4)0.0510 (11)
H190.64740.46860.69270.061*
C200.5665 (6)0.3740 (5)0.5084 (4)0.0493 (11)
C180.4783 (5)0.3921 (5)0.3929 (4)0.0479 (10)
H180.46430.31900.32170.057*
Cl210.6390 (5)0.2036 (3)0.5142 (4)0.0640 (9)0.50
C210.659 (3)0.2527 (18)0.522 (2)0.081 (2)0.50
H210.72550.25010.60050.097*0.50
O20.6509 (12)0.1563 (8)0.4337 (7)0.081 (2)0.50
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Pt10.01892 (8)0.01346 (8)0.01130 (7)0.00185 (5)0.00020 (5)0.00142 (5)
O10.0370 (12)0.0334 (13)0.0173 (10)0.0180 (10)0.0050 (9)0.0037 (9)
N20.0311 (13)0.0305 (15)0.0193 (12)0.0135 (11)0.0004 (10)0.0033 (10)
C30.0280 (14)0.0236 (15)0.0188 (13)0.0079 (12)0.0013 (11)0.0045 (11)
N40.0246 (12)0.0176 (12)0.0159 (11)0.0040 (9)0.0003 (9)0.0011 (9)
C50.0251 (14)0.0276 (16)0.0151 (13)0.0071 (12)0.0000 (11)0.0017 (11)
N60.0340 (14)0.0236 (13)0.0170 (11)0.0097 (11)0.0048 (10)0.0049 (10)
C70.0394 (18)0.0260 (17)0.0250 (15)0.0147 (14)0.0038 (13)0.0047 (13)
C80.045 (2)0.040 (2)0.0297 (17)0.0138 (16)0.0096 (15)0.0164 (15)
C90.053 (2)0.048 (2)0.0264 (17)0.0291 (19)0.0062 (16)0.0022 (16)
C100.0247 (14)0.0207 (15)0.0178 (13)0.0064 (11)0.0022 (11)0.0006 (11)
C110.051 (2)0.0262 (17)0.0257 (15)0.0055 (15)0.0084 (15)0.0094 (13)
C120.074 (3)0.0135 (16)0.0358 (18)0.0094 (16)0.0061 (18)0.0007 (14)
C130.054 (2)0.0323 (19)0.0212 (15)0.0222 (16)0.0059 (15)0.0002 (13)
Cl140.1140 (10)0.0441 (6)0.0333 (5)0.0409 (6)0.0248 (6)0.0019 (4)
C150.0342 (16)0.0305 (17)0.0308 (16)0.0112 (13)0.0120 (14)0.0087 (13)
C160.0235 (14)0.0187 (15)0.0309 (15)0.0017 (11)0.0043 (12)0.0022 (12)
Cl170.0284 (4)0.0283 (4)0.0350 (4)0.0005 (3)0.0072 (3)0.0162 (3)
C190.067 (3)0.069 (3)0.037 (2)0.037 (2)0.027 (2)0.028 (2)
C200.071 (3)0.058 (3)0.044 (2)0.042 (2)0.037 (2)0.028 (2)
C180.067 (3)0.058 (3)0.0366 (19)0.031 (2)0.0315 (19)0.0178 (18)
Cl210.100 (2)0.059 (2)0.0583 (16)0.0507 (19)0.0399 (15)0.0301 (19)
C210.145 (7)0.062 (5)0.059 (4)0.064 (5)0.043 (4)0.023 (4)
O20.145 (7)0.062 (5)0.059 (4)0.064 (5)0.043 (4)0.023 (4)
Geometric parameters (Å, º) top
Pt1—N42.018 (2)C9—H9B0.9600
Pt1—N4i2.018 (2)C9—H9C0.9600
Pt1—Cl172.3087 (7)C10—C111.381 (4)
Pt1—Cl17i2.3087 (7)C10—C161.385 (4)
O1—N21.490 (3)C11—H110.9300
O1—C51.360 (3)C11—C121.394 (5)
N2—H20.9100C12—H120.9300
N2—C31.474 (4)C12—C131.364 (5)
N2—C91.452 (4)C13—Cl141.754 (3)
C3—H30.9800C13—C151.385 (5)
C3—N41.476 (4)C15—H150.9300
C3—C101.505 (4)C15—C161.387 (4)
N4—C51.301 (4)C16—H160.9300
C5—N61.325 (4)C19—H190.9300
N6—C71.464 (4)C19—C201.389 (6)
N6—C81.467 (4)C19—C18ii1.378 (6)
C7—H7A0.9600C20—C181.391 (5)
C7—H7B0.9600C20—Cl211.782 (5)
C7—H7C0.9600C20—C211.465 (18)
C8—H8A0.9600C18—C19ii1.378 (6)
C8—H8B0.9600C18—H180.9300
C8—H8C0.9600C21—H210.9300
C9—H9A0.9600C21—O21.20 (2)
N4—Pt1—N4i180.0N2—C9—H9A109.5
N4i—Pt1—Cl1790.47 (7)N2—C9—H9B109.5
N4—Pt1—Cl1789.53 (7)N2—C9—H9C109.5
N4i—Pt1—Cl17i89.53 (7)H9A—C9—H9B109.5
N4—Pt1—Cl17i90.47 (7)H9A—C9—H9C109.5
Cl17—Pt1—Cl17i180.0H9B—C9—H9C109.5
C5—O1—N2103.2 (2)C11—C10—C3119.9 (3)
O1—N2—H2111.8C11—C10—C16119.8 (3)
C3—N2—O1101.1 (2)C16—C10—C3120.2 (3)
C3—N2—H2111.8C10—C11—H11119.9
C9—N2—O1106.0 (2)C10—C11—C12120.1 (3)
C9—N2—H2111.8C12—C11—H11119.9
C9—N2—C3113.6 (3)C11—C12—H12120.6
N2—C3—H3110.1C13—C12—C11118.8 (3)
N2—C3—N4101.0 (2)C13—C12—H12120.6
N2—C3—C10109.5 (2)C12—C13—Cl14119.9 (3)
N4—C3—H3110.1C12—C13—C15122.6 (3)
N4—C3—C10115.5 (2)C15—C13—Cl14117.5 (3)
C10—C3—H3110.1C13—C15—H15121.1
C3—N4—Pt1119.50 (17)C13—C15—C16117.8 (3)
C5—N4—Pt1133.5 (2)C16—C15—H15121.1
C5—N4—C3106.5 (2)C10—C16—C15120.9 (3)
N4—C5—O1114.1 (3)C10—C16—H16119.6
N4—C5—N6131.3 (3)C15—C16—H16119.6
N6—C5—O1114.5 (2)C20—C19—H19120.4
C5—N6—C7123.4 (2)C18ii—C19—H19120.4
C5—N6—C8120.6 (3)C18ii—C19—C20119.1 (4)
C7—N6—C8115.9 (3)C19—C20—C18121.0 (4)
N6—C7—H7A109.5C19—C20—Cl21121.3 (3)
N6—C7—H7B109.5C19—C20—C21116.0 (9)
N6—C7—H7C109.5C18—C20—Cl21117.5 (4)
H7A—C7—H7B109.5C18—C20—C21122.5 (9)
H7A—C7—H7C109.5C21—C20—Cl2111.6 (10)
H7B—C7—H7C109.5C19ii—C18—C20119.9 (4)
N6—C8—H8A109.5C19ii—C18—H18120.1
N6—C8—H8B109.5C20—C18—H18120.1
N6—C8—H8C109.5C20—C21—H21119.7
H8A—C8—H8B109.5O2—C21—C20120.5 (17)
H8A—C8—H8C109.5O2—C21—H21119.7
H8B—C8—H8C109.5
Pt1—N4—C5—O1179.0 (2)C9—N2—C3—C1088.6 (3)
Pt1—N4—C5—N60.1 (5)C10—C3—N4—Pt141.0 (3)
O1—N2—C3—N436.0 (3)C10—C3—N4—C5146.2 (3)
O1—N2—C3—C10158.3 (2)C10—C11—C12—C130.5 (5)
O1—C5—N6—C7172.6 (3)C11—C10—C16—C150.7 (4)
O1—C5—N6—C84.9 (5)C11—C12—C13—Cl14179.4 (3)
N2—O1—C5—N416.2 (3)C11—C12—C13—C151.1 (6)
N2—O1—C5—N6164.7 (3)C12—C13—C15—C160.7 (5)
N2—C3—N4—Pt1159.05 (18)C13—C15—C16—C100.2 (5)
N2—C3—N4—C528.1 (3)Cl14—C13—C15—C16179.7 (2)
N2—C3—C10—C11105.8 (3)C16—C10—C11—C120.4 (5)
N2—C3—C10—C1671.3 (3)Cl17—Pt1—N4—C361.0 (2)
C3—N4—C5—O17.6 (3)Cl17i—Pt1—N4—C3119.0 (2)
C3—N4—C5—N6171.3 (3)Cl17i—Pt1—N4—C570.5 (3)
C3—C10—C11—C12176.7 (3)Cl17—Pt1—N4—C5109.5 (3)
C3—C10—C16—C15176.4 (3)C19—C20—C18—C19ii0.1 (8)
N4i—Pt1—N4—C315 (24)C19—C20—C21—O2178.3 (15)
N4i—Pt1—N4—C5155 (24)C18ii—C19—C20—C180.1 (7)
N4—C3—C10—C11141.0 (3)C18ii—C19—C20—Cl21176.3 (4)
N4—C3—C10—C1641.9 (4)C18ii—C19—C20—C21172.0 (11)
N4—C5—N6—C76.3 (6)C18—C20—C21—O26 (3)
N4—C5—N6—C8176.2 (4)Cl21—C20—C18—C19ii176.4 (4)
C5—O1—N2—C332.6 (3)Cl21—C20—C21—O261 (4)
C5—O1—N2—C9151.3 (3)C21—C20—C18—C19ii171.4 (11)
C9—N2—C3—N4149.1 (3)
Symmetry codes: (i) x+1, y+1, z; (ii) x+1, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8···O2iii0.962.583.378 (9)141
C12—H12···Cl17iv0.932.703.589 (4)160
Symmetry codes: (iii) x, y+1, z; (iv) x+1, y, z.

Experimental details

Crystal data
Chemical formula[PtCl2(C11H15ClN3O)2]·C7H5ClO
Mr887.97
Crystal system, space groupTriclinic, P1
Temperature (K)100
a, b, c (Å)8.46436 (18), 9.38481 (19), 11.4373 (3)
α, β, γ (°)101.0381 (18), 104.9553 (19), 96.3847 (17)
V3)849.07 (3)
Z1
Radiation typeMo Kα
µ (mm1)4.57
Crystal size (mm)0.17 × 0.11 × 0.09
Data collection
DiffractometerAgilent Xcalibur Eos
diffractometer
Absorption correctionMulti-scan
(DENZO/SCALEPACK; Otwinowski & Minor, 1997)
Tmin, Tmax0.933, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
13908, 3892, 3888
Rint0.036
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.022, 0.054, 1.06
No. of reflections3892
No. of parameters211
No. of restraints0
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)1.63, 1.21

Computer programs: CrysAlis PRO (Agilent, 2012), SIR2004 (Burla et al., 2005), SHELXL97 (Sheldrick, 2008), OLEX2 (Dolomanov et al., 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8···O2i0.962.583.378 (9)141
C12—H12···Cl17ii0.932.703.589 (4)160
Symmetry codes: (i) x, y+1, z; (ii) x+1, y, z.
Acknowledgements top

This work was supported by Saint Petersburg State University research grant (2013–2015, 12.38.781.2013) and RFBR 12–03-33071. The XRD study was performed at the X-ray Diffraction Centre of Saint Petersburg State University.

references
References top

Agilent (2012). CrysAlis PRO and CrysAlis RED. Agilent Technologies, Yarnton, England.

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