trans-Dichloro­bis(piperidine-1-carbonitrile)­platinum(II)

In the title centrosymmetric complex, trans-[PtCl₂(C₆H₁₀N₂)₂], the Pt^II centre is coordinated by two piperidine-1-carbonitrile ligands and two chloro ligands, resulting in a typical square-planar geometry. The C-N distance between the nitrile and piperidine group [1.306 (4) Å] clearly indicates that this bond is not a pure single bond, being closer to a C=N double bond. This points to a noticeable contribution of the bipolar structure [Pt]-N^-=C=N⁺R₂ in the resonance hybrid of the push-pull nitrile ligand.

Key indicators

• Single-crystal X-ray study
• T = 120 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.021
• wR factor = 0.029
• Data-to-parameter ratio = 20.4

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT230_ALERT_2_C Hirshfeld Test Diff for    N2     -   C1      ..       5.85 su
PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X)  Pt1    -   Cl1     ..       5.09 su

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   2 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   0 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
   0 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: COLLECT (Nonius, 1997); cell refinement: EVALCCD (Duisenberg et al., 2003); data reduction: EVALCCD; program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Crystal Impact, 2005); software used to prepare material for publication: SHELXL97.

trans-Dichlorobis(piperidine-1-carbonitrile)platinum(II)

Crystal data

[PtCl2(C6H10N2)2]	F(000) = 928
Mr = 486.31	Dx = 2.059 Mg m^−3
Orthorhombic, Pccn	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ab 2ac	Cell parameters from 4024 reflections
a = 10.1398 (10) Å	θ = 1.0–27.5°
b = 11.2092 (10) Å	µ = 9.28 mm^−1
c = 13.8008 (12) Å	T = 120 K
V = 1568.6 (2) Å^3	Block, yellow
Z = 4	0.28 × 0.17 × 0.11 mm

Data collection

Nonius KappaCCD diffractometer	1799 independent reflections
Radiation source: fine-focus sealed tube	1069 reflections with I > 2σ(I)
Horizontally mounted graphite crystal monochromator	Rint = 0.046
Detector resolution: 9 pixels mm^-1	θmax = 27.5°, θmin = 2.7°
φ scans, and ω scans with κ offset	h = −13→13
Absorption correction: multi-scan (SADABS; Sheldrick, 2003)	k = −13→14
Tmin = 0.151, Tmax = 0.360	l = −17→17
19196 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.021	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.029	H-atom parameters constrained
S = 1.08	w = 1/[σ^2(Fo^2) + 2.4057P] where P = (Fo^2 + 2Fc^2)/3
1799 reflections	(Δ/σ)max < 0.001
88 parameters	Δρmax = 0.68 e Å^−3
0 restraints	Δρmin = −0.54 e Å^−3

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	0.5000	0.0000	0.5000	0.01164 (4)
Cl1	0.55331 (9)	0.16032 (8)	0.59487 (6)	0.02131 (18)
N1	0.3311 (3)	−0.0159 (3)	0.5654 (2)	0.0180 (7)
N2	0.1091 (3)	−0.0471 (3)	0.6304 (2)	0.0179 (8)
C1	0.2278 (3)	−0.0284 (3)	0.5972 (3)	0.0156 (8)
C2	0.0560 (3)	−0.1697 (3)	0.6315 (2)	0.0185 (8)
H2A	0.0651	−0.2043	0.6971	0.022*
H2B	0.1061	−0.2203	0.5856	0.022*
C3	−0.0863 (3)	−0.1666 (3)	0.6030 (3)	0.0195 (8)
H3A	−0.1245	−0.2475	0.6096	0.023*
H3B	−0.0938	−0.1423	0.5343	0.023*
C4	−0.1629 (4)	−0.0805 (3)	0.6654 (3)	0.0221 (9)
H4A	−0.1612	−0.1081	0.7336	0.027*
H4B	−0.2560	−0.0785	0.6438	0.027*
C5	−0.1047 (4)	0.0441 (3)	0.6593 (3)	0.0178 (9)
H5A	−0.1140	0.0744	0.5923	0.021*
H5B	−0.1543	0.0981	0.7028	0.021*
C6	0.0398 (3)	0.0444 (3)	0.6877 (3)	0.0173 (8)
H6A	0.0787	0.1239	0.6749	0.021*
H6B	0.0488	0.0270	0.7577	0.021*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Pt1	0.00965 (7)	0.01308 (7)	0.01218 (7)	−0.00065 (10)	0.00156 (11)	0.00122 (12)
Cl1	0.0263 (4)	0.0180 (4)	0.0196 (4)	−0.0043 (4)	0.0005 (4)	−0.0018 (4)
N1	0.0147 (14)	0.0202 (19)	0.0191 (15)	−0.0020 (14)	0.0036 (12)	−0.0011 (14)
N2	0.0100 (16)	0.0182 (17)	0.0255 (19)	−0.0030 (13)	0.0061 (14)	−0.0029 (14)
C1	0.0221 (19)	0.012 (2)	0.0129 (17)	−0.0002 (13)	−0.0022 (15)	−0.0014 (14)
C2	0.0195 (17)	0.0140 (18)	0.022 (2)	−0.0005 (16)	0.0053 (17)	−0.0017 (16)
C3	0.0147 (19)	0.0202 (19)	0.024 (2)	−0.0049 (16)	0.0050 (16)	−0.0039 (19)
C4	0.0157 (19)	0.024 (2)	0.026 (2)	−0.0055 (17)	0.0050 (17)	−0.0031 (18)
C5	0.016 (2)	0.018 (2)	0.019 (2)	0.0007 (16)	0.0019 (17)	−0.0018 (17)
C6	0.0176 (19)	0.0153 (16)	0.0189 (19)	−0.0020 (14)	0.0023 (15)	−0.0044 (15)

Geometric parameters (Å, º)

Pt1—N1	1.944 (3)	C3—C4	1.509 (5)
Pt1—N1^i	1.944 (3)	C3—H3A	0.9900
Pt1—Cl1	2.2882 (9)	C3—H3B	0.9900
Pt1—Cl1^i	2.2882 (9)	C4—C5	1.518 (5)
N1—C1	1.144 (4)	C4—H4A	0.9900
N2—C1	1.306 (4)	C4—H4B	0.9900
N2—C6	1.474 (4)	C5—C6	1.517 (5)
N2—C2	1.476 (4)	C5—H5A	0.9900
C2—C3	1.496 (5)	C5—H5B	0.9900
C2—H2A	0.9900	C6—H6A	0.9900
C2—H2B	0.9900	C6—H6B	0.9900
N1—Pt1—N1^i	180	C4—C3—H3B	109.4
N1—Pt1—Cl1	90.83 (9)	H3A—C3—H3B	108.0
N1^i—Pt1—Cl1	89.17 (9)	C3—C4—C5	110.9 (3)
N1—Pt1—Cl1^i	89.17 (9)	C3—C4—H4A	109.5
N1^i—Pt1—Cl1^i	90.83 (9)	C5—C4—H4A	109.5
Cl1—Pt1—Cl1^i	180	C3—C4—H4B	109.5
C1—N1—Pt1	174.7 (3)	C5—C4—H4B	109.5
C1—N2—C6	121.1 (3)	H4A—C4—H4B	108.1
C1—N2—C2	119.3 (3)	C6—C5—C4	111.3 (3)
C6—N2—C2	118.0 (3)	C6—C5—H5A	109.4
N1—C1—N2	177.1 (4)	C4—C5—H5A	109.4
N2—C2—C3	109.1 (3)	C6—C5—H5B	109.4
N2—C2—H2A	109.9	C4—C5—H5B	109.4
C3—C2—H2A	109.9	H5A—C5—H5B	108.0
N2—C2—H2B	109.9	N2—C6—C5	108.7 (3)
C3—C2—H2B	109.9	N2—C6—H6A	110.0
H2A—C2—H2B	108.3	C5—C6—H6A	110.0
C2—C3—C4	111.2 (3)	N2—C6—H6B	110.0
C2—C3—H3A	109.4	C5—C6—H6B	110.0
C4—C3—H3A	109.4	H6A—C6—H6B	108.3
C2—C3—H3B	109.4

Symmetry code: (i) −x+1, −y, −z+1.