Bis(4,4′-bipyridin-1-ium) cis-bis­(1,2-di­cyano-2-sulfido­ethene-1-sulfinato-κ2S,S′)platinate(2−)

Welton, C.E.; Reinheimer, E.W.; Smucker, B.W.

doi:10.1107/S2414314625003839

metal-organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 10| Part 5| May 2025| x250383

https://doi.org/10.1107/S2414314625003839

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Bis(4,4′-bipyridin-1-ium) cis-bis(1,2-dicyano-2-sulfidoethene-1-sulfinato-κ²S,S′)platinate(2−)

Claire E. Welton,^a Eric W. Reinheimer ^b and Bradley W. Smucker ^a ^*

^a900 N Grand Avenue, Suite 61651, Austin College, Sherman, TX 75090, USA, and ^bRigaku Oxford Diffraction, 9009 New Trails Dr., The Woodlands, TX 77381, USA
^*Correspondence e-mail: bsmucker@austincollege.edu

Edited by S. Bernès, Benemérita Universidad Autónoma de Puebla, México (Received 21 February 2025; accepted 28 April 2025; online 23 May 2025)

Crystals of the sulfinate-containing platinate salt, (C₁₀H₉N₂)₂[Pt(C₄N₂O₂S₂)₂], were obtained from a solution of [Pt(4,4′-bpy)₂(mnt)] after a long period with minimal light (4,4′-bpy is 4,4′-bipyridine and mnt is maleonitriledithiolate). In the crystals, the cations associate via C—H⋯O hydrogen bonds with hydrogen bonded (—H⋯) chains of pyridinium anions. The cis-geometry of the sulfinate around the square-planar platinum atom, coupled with a torsion of one of the rings of the pyridinium, engenders multiple hydrogen bonds between the sulfinate oxygen atoms and the pyridinium hydrogen atoms.

Keywords: crystal structure; sulfinate; platinum; salt; pyridinium.

CCDC reference: 2447480

Structure description

The asymmetric unit of the title compound contains one-half of the platinum bis-sulfinate moiety with the platinum residing on an inversion centre and a single pyridinium cation. The square-planar platinate anions have the sulfinate moieties in a cis arrangement around the platinum atom (Fig. 1). The Pt—S distances between the S2 thiolate and the S1 sulfinate are 2.3120 (13) and 2.2554 (12) Å, respectively. The S=O bond distances [S1=O1 = 1.448 (4) and S1=O2 = 1.439 (4) Å] in this structure match the S=O distances of 1.470 (4) and 1.444 (4) Å observed in platinum(II) sulfinato-thiolato complexes (Ishii et al., 2007 ). The S—O single-bond distances in sulfenato ligands typically are around 0.1 Å longer at 1.55 Å (Buonomo et al., 1995 ).

Figure 1
Ellipsoid representation (50% probability) of the title compound showing O⋯H distances for hydrogen bonds between O1 and H8 and O2(−x + 1, y, −z + $[{3\over 2}]$ ) and H8 and H7.

The pyridinium cations form hydrogen-bonded one-dimensional chains along the c-axis direction, which surround the platinate anions. These anions are slipped-stacked so as to fit between the pyridinium chains (Fig. 2). This type of packing of the anions is observed in a [Pt(mnt)₂]⁻ salt with a planar 4-aminopyridinium monocation (Pei et al., 2012 ), but when [Pt(mnt)₂]²⁻ crystallizes with a planar dicationic [4,4′-H₂bpy]²⁺ it forms ABAB stacks of alternating cations and anions (Crawford et al., 2004 ). The sulfinate moieties alternate their positions along the slipped stacking of the anions, which corresponds to a rotation between the two rings of the pyridinium cation [torsion angle C8—C9—C10—C11 of 130.8 (5)°], that positions the H8 and H7 hydrogen atoms for H-bonding with the O1 and O2(−x + 1, y, −z + $[{3\over 2}]$ ) atoms of the sulfinates (Table 1 and Fig. 1).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N4—H4⋯N3ⁱ	0.86	1.88	2.730 (5)	171
C7—H7⋯N2ⁱⁱ	0.93	2.50	3.363 (7)	155
C7—H7⋯O2ⁱⁱⁱ	0.93	2.57	3.197 (7)	125
C8—H8⋯O1	0.93	2.40	3.301 (6)	164
C8—H8⋯O2ⁱⁱⁱ	0.93	2.77	3.287 (7)	116
Symmetry codes: (i) $[x, -y, z-{\script{1\over 2}}]$ ; (ii) $[x, -y+1, z+{\script{1\over 2}}]$ ; (iii) $[-x+1, y, -z+{\script{3\over 2}}]$ .

Figure 2
Ellipsoid representation (50% probability) of the packing of the title compound with pyridinium chains connected by hydrogen bonds between N3 of one pyridinium and the H4 of an adjacent pyridinium. The H-bond distance between N3(−x + $[{3\over 2}]$ , y + $[{1\over 2}]$ , −z + $[{3\over 2}]$ ) and H4(−x + $[{3\over 2}]$ , −y + $[{1\over 2}]$ , −z + 1) is shown. Some symmetry-related cell contents were removed for clarity.

Synthesis and crystallization

A methanol/water (1:1) solution containing [Pt(4,4′-bpy)₂(mnt)] (Smith et al. 2019 ; 4,4′-bpy is 4,4′-bipyridine and mnt is maleonitriledithiolate) was combined with excess 4,4′-bpy due to the observed exchangeability of the 4,4′-bpy ligand. This solution was layered with THF in a thin tube. Small orange prisms were harvested from the bottom of the tube after a long period with minimal light. This conversion of a dithiolate ligand to its monosulfinate derivative has been achieved through multiple modes including: photooxidation in the presence of water (Connick & Gray, 1997 ), chemical oxidation (Sugimoto et al., 2000 ; Ishii et al., 2007), or after a prolonged period in minimal light (Stace et al., 2016 ). Protons for the pyridinium likely originated from the solvents.

Refinement

Crystal data, data collection, and refinement details are summarized in Table 2.

Table 2
Experimental details

Crystal data
Chemical formula	(C₁₀H₉N₂)₂[Pt(C₄N₂O₂S₂)₂]
M_r	853.83
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	293
a, b, c (Å)	14.5669 (8), 10.8981 (6), 19.4595 (9)
β (°)	98.782 (5)
V (Å³)	3053.0 (3)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	4.92
Crystal size (mm)	0.09 × 0.07 × 0.03

Data collection
Diffractometer	XtaLAB Mini II
Absorption correction	Analytical (CrysAlis PRO; Rigaku OD, 2024 $[Rigaku OD (2024). CrysAlis PRO. Rigaku Oxford Diffraction, Rigaku Corporation, Oxford, England.]$ )
T_min, T_max	0.712, 0.851
No. of measured, independent and observed [I > 2σ(I)] reflections	21005, 3124, 2503
R_int	0.042
(sin θ/λ)_max (Å⁻¹)	0.625

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.031, 0.066, 1.04
No. of reflections	3124
No. of parameters	204
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.71, −0.52
Computer programs: CrysAlis PRO (Rigaku OD, 2024 $[Rigaku OD (2024). CrysAlis PRO. Rigaku Oxford Diffraction, Rigaku Corporation, Oxford, England.]$ ), SHELXT2018/2 (Sheldrick, 2015a ), SHELXL2014/7 (Sheldrick, 2015b ), Mercury (Macrae et al., 2020 ), OLEX2 (Dolomanov et al., 2009 ) and publCIF (Westrip, 2010 ).

Structural data

CCDC reference: 2447480

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2414314625003839/bh4095sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314625003839/bh4095Isup2.hkl

checkCIF report

Computing details top

Bis(4,4'-bipyridin-1-ium) cis-bis(1,2-dicyano-2-sulfidoethene-1-sulfinato-κ²S,S')platinate(2-) top

Crystal data top

(C₁₀H₉N₂)₂[Pt(C₄N₂O₂S₂)₂]	F(000) = 1664
M_r = 853.83	D_x = 1.858 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
a = 14.5669 (8) Å	Cell parameters from 2218 reflections
b = 10.8981 (6) Å	θ = 2.4–25.0°
c = 19.4595 (9) Å	µ = 4.92 mm⁻¹
β = 98.782 (5)°	T = 293 K
V = 3053.0 (3) Å³	Irregular, orange
Z = 4	0.09 × 0.07 × 0.03 mm

Data collection top

XtaLAB Mini II diffractometer	3124 independent reflections
Radiation source: fine-focus sealed X-ray tube, Rigaku (Mo) X-ray Source	2503 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.042
Detector resolution: 10.0000 pixels mm^-1	θ_max = 26.4°, θ_min = 2.5°
ω scans	h = −18→18
Absorption correction: analytical (CrysAlisPro; Rigaku OD, 2024)	k = −13→13
T_min = 0.712, T_max = 0.851	l = −22→24
21005 measured reflections

Refinement top

Refinement on F²	Primary atom site location: dual
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.031	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.066	H-atom parameters constrained
S = 1.04	w = 1/[σ²(F_o²) + (0.0297P)² + 5.2814P] where P = (F_o² + 2F_c²)/3
3124 reflections	(Δ/σ)_max = 0.001
204 parameters	Δρ_max = 0.71 e Å⁻³
0 restraints	Δρ_min = −0.52 e Å⁻³

Special details top

Refinement. H atoms bound to C and N atoms were positioned geometrically (C—H = 0.93 Å and N—H = 0.86 Å) and constrained to ride on the parent atom. U_iso(H) values were fixed at multiples of U_eq(C) [1.2 for C(H) and N(H) groups].

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Pt1	0.5000	0.54391 (3)	0.7500	0.03897 (10)
S1	0.53256 (8)	0.39852 (12)	0.67484 (5)	0.0419 (3)
S2	0.53745 (10)	0.69516 (13)	0.67571 (6)	0.0578 (4)
O1	0.6114 (3)	0.3230 (4)	0.7024 (2)	0.0851 (13)
O2	0.4521 (3)	0.3318 (4)	0.6426 (2)	0.0870 (13)
N1	0.6220 (3)	0.3574 (5)	0.5069 (2)	0.0660 (13)
N2	0.6297 (4)	0.7379 (5)	0.5134 (2)	0.0909 (18)
C1	0.5992 (3)	0.4160 (5)	0.5502 (2)	0.0463 (13)
C2	0.5716 (3)	0.4857 (5)	0.6059 (2)	0.0422 (12)
C3	0.5720 (3)	0.6082 (5)	0.6092 (2)	0.0463 (12)
C4	0.6036 (4)	0.6797 (5)	0.5551 (3)	0.0607 (15)
N3	0.6676 (3)	−0.0315 (4)	0.91351 (18)	0.0501 (10)
N4	0.6763 (3)	0.0238 (4)	0.55456 (18)	0.0539 (11)
H4	0.6777	0.0327	0.5108	0.065*
C5	0.6851 (3)	−0.1265 (5)	0.8051 (2)	0.0490 (12)
H5	0.6972	−0.1970	0.7811	0.059*
C6	0.6820 (3)	−0.1305 (6)	0.8767 (2)	0.0530 (13)
H6	0.6904	−0.2057	0.8994	0.064*
C7	0.6538 (4)	0.0747 (5)	0.8800 (2)	0.0566 (15)
H7	0.6444	0.1445	0.9055	0.068*
C8	0.6526 (4)	0.0866 (5)	0.8087 (2)	0.0513 (13)
H8	0.6403	0.1621	0.7870	0.062*
C9	0.6698 (3)	−0.0150 (4)	0.7708 (2)	0.0371 (11)
C10	0.6723 (3)	−0.0038 (4)	0.6942 (2)	0.0390 (11)
C11	0.7447 (3)	−0.0520 (5)	0.6645 (2)	0.0512 (13)
H11	0.7928	−0.0941	0.6915	0.061*
C12	0.7449 (4)	−0.0366 (5)	0.5939 (2)	0.0578 (14)
H12	0.7934	−0.0689	0.5735	0.069*
C13	0.6066 (4)	0.0702 (5)	0.5822 (2)	0.0557 (14)
H13	0.5595	0.1119	0.5539	0.067*
C14	0.6023 (4)	0.0579 (5)	0.6520 (2)	0.0537 (13)
H14	0.5526	0.0908	0.6706	0.064*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Pt1	0.04944 (16)	0.04359 (17)	0.02506 (13)	0.000	0.00946 (10)	0.000
S1	0.0532 (7)	0.0454 (7)	0.0290 (6)	−0.0023 (6)	0.0125 (5)	0.0011 (5)
S2	0.0908 (10)	0.0468 (8)	0.0387 (7)	−0.0084 (7)	0.0192 (7)	0.0017 (6)
O1	0.106 (3)	0.090 (3)	0.061 (2)	0.019 (3)	0.017 (2)	0.006 (2)
O2	0.096 (3)	0.098 (4)	0.070 (3)	−0.023 (3)	0.023 (2)	−0.016 (3)
N1	0.074 (3)	0.089 (4)	0.039 (2)	0.001 (3)	0.019 (2)	−0.009 (3)
N2	0.133 (5)	0.095 (4)	0.048 (3)	−0.041 (4)	0.024 (3)	0.010 (3)
C1	0.048 (3)	0.060 (4)	0.030 (2)	−0.005 (2)	0.005 (2)	0.002 (2)
C2	0.046 (3)	0.055 (4)	0.027 (2)	−0.001 (2)	0.008 (2)	0.006 (2)
C3	0.050 (3)	0.061 (4)	0.027 (2)	−0.004 (3)	0.006 (2)	0.006 (2)
C4	0.080 (4)	0.067 (4)	0.036 (3)	−0.020 (3)	0.010 (3)	0.003 (3)
N3	0.060 (2)	0.071 (3)	0.0202 (17)	0.005 (2)	0.0091 (17)	0.000 (2)
N4	0.086 (3)	0.058 (3)	0.0185 (17)	−0.007 (3)	0.010 (2)	0.0003 (19)
C5	0.066 (3)	0.057 (3)	0.024 (2)	−0.005 (3)	0.008 (2)	−0.004 (2)
C6	0.065 (3)	0.064 (4)	0.029 (2)	−0.004 (3)	0.003 (2)	0.007 (3)
C7	0.073 (4)	0.068 (4)	0.029 (2)	0.014 (3)	0.010 (2)	−0.013 (2)
C8	0.076 (4)	0.051 (3)	0.028 (2)	0.015 (3)	0.010 (2)	0.000 (2)
C9	0.045 (2)	0.045 (3)	0.021 (2)	−0.002 (2)	0.0061 (18)	−0.0001 (19)
C10	0.053 (3)	0.041 (3)	0.023 (2)	−0.004 (2)	0.007 (2)	−0.0033 (18)
C11	0.060 (3)	0.066 (4)	0.028 (2)	0.006 (3)	0.010 (2)	0.000 (3)
C12	0.070 (3)	0.077 (4)	0.030 (2)	0.005 (3)	0.019 (2)	−0.001 (3)
C13	0.080 (4)	0.057 (4)	0.029 (2)	0.012 (3)	0.004 (2)	0.004 (2)
C14	0.067 (3)	0.067 (4)	0.029 (2)	0.011 (3)	0.013 (2)	−0.004 (2)

Geometric parameters (Å, º) top

Pt1—S1ⁱ	2.2554 (12)	C5—H5	0.9300
Pt1—S1	2.2554 (12)	C5—C6	1.402 (6)
Pt1—S2ⁱ	2.3120 (13)	C5—C9	1.387 (7)
Pt1—S2	2.3120 (13)	C6—H6	0.9300
S1—O1	1.448 (4)	C7—H7	0.9300
S1—O2	1.439 (4)	C7—C8	1.392 (6)
S1—C2	1.805 (5)	C8—H8	0.9300
S2—C3	1.740 (5)	C8—C9	1.375 (6)
N1—C1	1.147 (6)	C9—C10	1.501 (5)
N2—C4	1.139 (6)	C10—C11	1.382 (6)
C1—C2	1.431 (7)	C10—C14	1.383 (7)
C2—C3	1.337 (7)	C11—H11	0.9300
C3—C4	1.440 (7)	C11—C12	1.384 (6)
N3—C6	1.330 (6)	C12—H12	0.9300
N3—C7	1.328 (6)	C13—H13	0.9300
N4—H4	0.8600	C13—C14	1.376 (6)
N4—C12	1.335 (7)	C14—H14	0.9300
N4—C13	1.321 (6)

S1ⁱ—Pt1—S1	90.74 (6)	N3—C6—C5	122.8 (5)
S1—Pt1—S2	90.13 (4)	N3—C6—H6	118.6
S1ⁱ—Pt1—S2	178.08 (5)	C5—C6—H6	118.6
S1ⁱ—Pt1—S2ⁱ	90.13 (4)	N3—C7—H7	118.4
S1—Pt1—S2ⁱ	178.08 (5)	N3—C7—C8	123.3 (5)
S2ⁱ—Pt1—S2	89.05 (7)	C8—C7—H7	118.4
O1—S1—Pt1	113.09 (17)	C7—C8—H8	120.5
O1—S1—C2	104.6 (2)	C9—C8—C7	119.0 (5)
O2—S1—Pt1	113.54 (18)	C9—C8—H8	120.5
O2—S1—C2	105.7 (2)	C5—C9—C10	121.5 (4)
C2—S1—Pt1	103.49 (17)	C8—C9—C5	118.4 (4)
C3—S2—Pt1	101.52 (18)	C8—C9—C10	120.1 (4)
N1—C1—C2	178.0 (6)	C11—C10—C9	121.4 (4)
C1—C2—S1	116.2 (4)	C11—C10—C14	118.5 (4)
C3—C2—S1	119.4 (4)	C14—C10—C9	120.1 (4)
C3—C2—C1	124.5 (4)	C10—C11—H11	120.4
C2—C3—S2	125.4 (4)	C10—C11—C12	119.1 (5)
C2—C3—C4	120.4 (5)	C12—C11—H11	120.4
C4—C3—S2	114.2 (4)	N4—C12—C11	120.9 (5)
N2—C4—C3	178.6 (6)	N4—C12—H12	119.5
C7—N3—C6	117.9 (4)	C11—C12—H12	119.5
C12—N4—H4	119.7	N4—C13—H13	119.4
C13—N4—H4	119.7	N4—C13—C14	121.2 (5)
C13—N4—C12	120.7 (4)	C14—C13—H13	119.4
C6—C5—H5	120.7	C10—C14—H14	120.2
C9—C5—H5	120.7	C13—C14—C10	119.5 (5)
C9—C5—C6	118.6 (5)	C13—C14—H14	120.2

Pt1—S1—C2—C1	178.9 (3)	C6—N3—C7—C8	0.7 (8)
Pt1—S1—C2—C3	−1.9 (4)	C6—C5—C9—C8	0.3 (7)
Pt1—S2—C3—C2	1.7 (5)	C6—C5—C9—C10	179.8 (4)
Pt1—S2—C3—C4	−177.6 (3)	C7—N3—C6—C5	1.5 (7)
S1—C2—C3—S2	0.1 (6)	C7—C8—C9—C5	1.7 (7)
S1—C2—C3—C4	179.4 (4)	C7—C8—C9—C10	−177.8 (5)
O1—S1—C2—C1	60.3 (4)	C8—C9—C10—C11	130.8 (5)
O1—S1—C2—C3	−120.6 (4)	C8—C9—C10—C14	−47.9 (7)
O2—S1—C2—C1	−61.5 (4)	C9—C5—C6—N3	−2.0 (7)
O2—S1—C2—C3	117.7 (4)	C9—C10—C11—C12	−178.5 (5)
C1—C2—C3—S2	179.2 (3)	C9—C10—C14—C13	178.4 (5)
C1—C2—C3—C4	−1.5 (8)	C10—C11—C12—N4	0.1 (9)
N3—C7—C8—C9	−2.4 (8)	C11—C10—C14—C13	−0.3 (8)
N4—C13—C14—C10	0.2 (8)	C12—N4—C13—C14	0.1 (8)
C5—C9—C10—C11	−48.7 (7)	C13—N4—C12—C11	−0.2 (8)
C5—C9—C10—C14	132.6 (5)	C14—C10—C11—C12	0.2 (8)

Symmetry code: (i) −x+1, y, −z+3/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N4—H4···N3ⁱⁱ	0.86	1.88	2.730 (5)	171
C7—H7···N2ⁱⁱⁱ	0.93	2.50	3.363 (7)	155
C7—H7···O2ⁱ	0.93	2.57	3.197 (7)	125
C8—H8···O1	0.93	2.40	3.301 (6)	164
C8—H8···O2ⁱ	0.93	2.77	3.287 (7)	116

Symmetry codes: (i) −x+1, y, −z+3/2; (ii) x, −y, z−1/2; (iii) x, −y+1, z+1/2.

Funding information

Funding for this research was provided by: Welch Foundation (grant No. AD-0007 to Austin College Chemistry Department); Jerry Taylor and Nancy Bryant Foundation (gift to Austin College Science Division).

References

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