research communications
of caesium tetramethyldithioimidodiphosphinate
aCentro de Investigaciónes Químicas, Universidad Autónoma del Estado de Morelos, Av. Universidad No. 1001, Col. Chamilpa, CP 62209, Cuernavaca, Mor., Mexico, bCentro Conjunto de Investigación en Química Sustentable UAEM-UNAM, Carretera Toluca-Atlacomulco Km. 14.5, Toluca, 50200, Estado de México, Mexico, and cInstituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, México, 10810, Ciudad de México, Mexico
*Correspondence e-mail: cea@unam.mx
In the title crystal, the salt [CsMe2P(S)NP(S)Me2] is self-assembled as an undulating supramolecular two-dimensional polymeric structure, poly[(μ4-tetramethyldithioimidodiphosphinato)caesium], [Cs(C4H12NP2S2)]n, which is parallel to the bc plane. The Cs cations are hexacoordinated, being chelated by two thioimidophosphinate groups and two sulfur atoms from neighboring ligands. The anions are linked to the Cs cations by Cs⋯S and Cs⋯N electrostatic interactions.
Keywords: crystal structure; caesium; tetramethyldithioimidodiphosphinate anion; two-dimensional polymer structure.
CCDC reference: 2110998
1. Chemical context
Dichalcogenoimidodiphosphinate anions [R2P(E)NP(E)R2]− (E = O, S, Se, Te) are versatile complexing reagents with a strong tendency to form inorganic (carbon-free) chelate rings (Haiduc & Silaghi-Dumitrescu, 1986; Cea-Olivares & Muñoz, 1993; Hernández-Arganis et al., 2004; Slawin et al., 1994). The monoanionic ligands have been investigated as ligands for both main-group elements (Silvestru & Drake, 2001; Woollins, 1996) and transition metals (Rudler et al., 1997). The widespread interest in dichalcogenoimidodiphosphinates stems from their potential uses as lanthanide shift reagents (Rudler et al., 1997), industrial catalysts (Leung et al., 2000; Yamazaki et al., 2020), luminescent materials (Ma et al., 2019) as well as in metal extraction processes (du Preez et al., 1992). As part of our ongoing research on dichalcogenoimidodiphosphinate anions, we report herein the synthesis and crystallographic study of the title compound (I).
2. Structural commentary
In the I) (Fig. 1), the tetramethyldithioimidodiphosphinate anion is bent with a P—N—P angle of 132.16 (6)°, and chelates the Cs cation through S⋯Cs⋯N electrostatic interactions [S⋯Cs⋯N = 53.074 (17)°; S⋯Cs = 3.4377 (3) Å; N⋯Cs = 3.2054 (9) Å]. The bond distances of 2.0003 (4), 1.6075 (10), 1.6179 (10) and 1.9869 (4) Å for S1—P1, P1—N1, N1—P2 and P2—S2, respectively, suggest that the anion is a delocalized system (Cea-Olivares & Nöth, 1987; Churchill et al., 1971). The phosphorus atoms are in an approximately tetrahedral environment, the average bond angles being S—P—N = 113.9°, S—P—C = 109.4°, and C—P—C = 103.4°.
of the title compound (3. Supramolecular features
In the crystal, the salt [CsMe2P(S)NP(S)Me2] (I) is self-assembled as an undulating supramolecular 2D polymeric structure, which is parallel to the bc plane (Figs. 2 and 3). The Cs cations are hexacoordinated and linked to four different anions by Cs⋯S and Cs⋯N electrostatic interactions (Fig. 4). Analysis of this CsS4N2 polyhedron with the SHAPE 2.1 program (Llunell et al., 2013) gave CShM values of 9.50434 and 8.43874 for a regular octahedron and a trigonal prism, respectively, meaning that the coordination environment of the cesium atom is highly irregular. These polyhedra interconnect either by sharing vertices or an edge. The Cs⋯S ionic bond distances vary from 3.4377 (3) to 3.4726 (3) Å, which are close to the value of 3.51Å predicted from the ionic radii (Shannon, 1976). Regarding the N—Cs bond distances, two different distances were determined. One of them is 3.2054 (9) Å, which is close to the value of 3.13 Å predicted from the ionic radii, and the other is 3.651 Å, which is less than the value of 4.4 Å predicted from the van der Waals radii (Batsanov, 2001). Furthermore, five methyl groups are located in a close vicinity of the Cs+ cation with the Cs⋯H distance shorter than 4 Å, but only the shortest Cs1⋯H2C(1 – x, 1 – y, 1 – z) distance of 3.269 Å is similar to those observed in [LiCs(HMDS)2]∞ and can be labeled as an agostic interaction (Ojeda-Amador et al., 2016). The cyclic motifs Cs2S2, Cs2N2, Cs2N2P2S2 in this arrangement possess crystallographic inversion symmetry.
4. Database survey
The current version of the Cambridge Structural Database (Version 2021.1, updated August 2021; Groom et al., 2016) contains only three cesium dichalcogenoimidodiphosphinates, (18C6)CsPh2P(E)NP(E)Ph2 (BENSAP, BENSET and BENSIX for E = O, S and Se; Hernández-Arganis et al., 2004). Furthermore, only five compounds each containing two [Me2P(S)NP(S)Me2]− ligands and one M2+ cation (M = Fe, Ni, Pd, Cd, Co) are included in the database: IMSPFE10, IMSPNI10, OCANEL, TASXAN and ZACZAE (Churchill & Wormald, 1971; Churchill et al., 1971; Bilic et al., 2000; Ghesner et al., 2005 and Silvestru et al., 1995). The dinuclear species MIWYUM with two [Mn(CO)3]+ cations (Zuniga-Villarreal et al., 2001) is also noteworthy. No compound with [Me2P(E)NP(E)Me2]− (E = O or Se) is included in the database.
5. Synthesis and crystallization
Cs[Me2P(S)]2N (I) was obtained by the reaction of [Me2P(S)NHP(S)(Me2)] with Cs2CO3, according to a method previously described (Schmidpeter & Ebeling, 1968) and isolated solvent-free. The salt Cs[Me2P(S)]2N was recrystallized by slow evaporation from methanol. The spectroscopic data of the received sample (vide infra) coincided with the published ones and are therefore not reported; however, they can be consulted in the above-mentioned reference.
6. Refinement
Crystal data, data collection and structure . H atoms were positioned geometrically (C—H = 0.98 Å) and constrained using the riding-model approximation with Uiso(H) = 1.5 Ueq(C).
details are summarized in Table 1Supporting information
CCDC reference: 2110998
https://doi.org/10.1107/S2056989021009798/dj2031sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989021009798/dj2031Isup2.hkl
Data collection: APEX3 (Bruker, 2016); cell
SAINT (Bruker, 2016); data reduction: SAINT (Bruker, 2016); program(s) used to solve structure: ShelXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL (Sheldrick, 2015b); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).[Cs(C4H12NP2S2)] | F(000) = 640 |
Mr = 333.12 | Dx = 1.968 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 11.0320 (2) Å | Cell parameters from 4791 reflections |
b = 12.4326 (3) Å | θ = 2.4–25.2° |
c = 8.2173 (2) Å | µ = 3.89 mm−1 |
β = 93.8752 (4)° | T = 100 K |
V = 1124.48 (4) Å3 | Plate, clear light white |
Z = 4 | 0.18 × 0.15 × 0.12 mm |
Bruker SMART APEXII DUO diffractometer | 5097 independent reflections |
Radiation source: Incoatec ImuS with multilayer mirrors | 4791 reflections with I > 2σ(I) |
Detector resolution: 8.333 pixels mm-1 | Rint = 0.017 |
ω scans | θmax = 36.3°, θmin = 2.5° |
Absorption correction: multi-scan (SADABS; Bruker, 2016) | h = −17→17 |
Tmin = 0.100, Tmax = 0.147 | k = −19→20 |
15582 measured reflections | l = −13→13 |
Refinement on F2 | Primary atom site location: dual |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.017 | H-atom parameters constrained |
wR(F2) = 0.035 | w = 1/[σ2(Fo2) + (0.0129P)2 + 0.2359P] where P = (Fo2 + 2Fc2)/3 |
S = 1.08 | (Δ/σ)max = 0.004 |
5097 reflections | Δρmax = 0.58 e Å−3 |
95 parameters | Δρmin = −0.76 e Å−3 |
0 restraints |
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. |
x | y | z | Uiso*/Ueq | ||
Cs1 | 0.56629 (2) | 0.59017 (2) | 0.27106 (2) | 0.01538 (2) | |
S1 | 0.40180 (2) | 0.36434 (2) | 0.15753 (4) | 0.01505 (5) | |
S2 | 0.16545 (3) | 0.55491 (2) | 0.67865 (3) | 0.01535 (5) | |
P1 | 0.25673 (2) | 0.42906 (2) | 0.25349 (3) | 0.01072 (5) | |
P2 | 0.21826 (2) | 0.61338 (2) | 0.46982 (3) | 0.01115 (5) | |
N1 | 0.29485 (8) | 0.53396 (8) | 0.35928 (11) | 0.01287 (16) | |
C1 | 0.14280 (11) | 0.45999 (10) | 0.09220 (14) | 0.0180 (2) | |
H1A | 0.1713 | 0.5193 | 0.0261 | 0.027* | |
H1B | 0.0672 | 0.4811 | 0.1397 | 0.027* | |
H1C | 0.1280 | 0.3964 | 0.0232 | 0.027* | |
C2 | 0.18262 (11) | 0.32802 (10) | 0.37023 (15) | 0.0181 (2) | |
H2A | 0.1574 | 0.2678 | 0.2988 | 0.027* | |
H2B | 0.1111 | 0.3595 | 0.4165 | 0.027* | |
H2C | 0.2392 | 0.3021 | 0.4586 | 0.027* | |
C3 | 0.08798 (10) | 0.67113 (10) | 0.35577 (14) | 0.0165 (2) | |
H3A | 0.1128 | 0.6988 | 0.2514 | 0.025* | |
H3B | 0.0551 | 0.7301 | 0.4185 | 0.025* | |
H3C | 0.0255 | 0.6158 | 0.3356 | 0.025* | |
C4 | 0.31966 (11) | 0.72634 (9) | 0.50889 (15) | 0.0169 (2) | |
H4A | 0.3379 | 0.7596 | 0.4052 | 0.025* | |
H4B | 0.3952 | 0.7012 | 0.5661 | 0.025* | |
H4C | 0.2807 | 0.7794 | 0.5766 | 0.025* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cs1 | 0.01350 (3) | 0.01249 (3) | 0.02027 (4) | −0.00100 (2) | 0.00205 (2) | −0.00067 (2) |
S1 | 0.01356 (11) | 0.01225 (11) | 0.01975 (12) | 0.00045 (9) | 0.00416 (9) | −0.00285 (9) |
S2 | 0.01700 (12) | 0.01704 (12) | 0.01254 (11) | 0.00079 (10) | 0.00488 (9) | 0.00192 (9) |
P1 | 0.01031 (10) | 0.01168 (11) | 0.01021 (11) | −0.00022 (9) | 0.00089 (8) | 0.00053 (8) |
P2 | 0.01079 (11) | 0.01129 (11) | 0.01158 (11) | 0.00056 (9) | 0.00243 (9) | 0.00048 (9) |
N1 | 0.0121 (4) | 0.0131 (4) | 0.0136 (4) | −0.0001 (3) | 0.0023 (3) | −0.0024 (3) |
C1 | 0.0179 (5) | 0.0217 (5) | 0.0138 (5) | 0.0031 (4) | −0.0035 (4) | −0.0002 (4) |
C2 | 0.0184 (5) | 0.0178 (5) | 0.0182 (5) | −0.0051 (4) | 0.0030 (4) | 0.0026 (4) |
C3 | 0.0139 (4) | 0.0177 (5) | 0.0180 (5) | 0.0024 (4) | 0.0024 (4) | 0.0046 (4) |
C4 | 0.0167 (5) | 0.0149 (5) | 0.0193 (5) | −0.0021 (4) | 0.0040 (4) | −0.0031 (4) |
Cs1—S1 | 3.4377 (3) | P1—C2 | 1.8090 (12) |
Cs1—S1i | 3.4726 (3) | P2—Cs1iii | 3.9879 (3) |
Cs1—S1ii | 3.6077 (3) | P2—N1 | 1.6179 (10) |
Cs1—S2iii | 3.4667 (3) | P2—C3 | 1.8103 (11) |
Cs1—N1iii | 3.6506 (9) | P2—C4 | 1.8107 (12) |
Cs1—N1 | 3.2054 (9) | N1—Cs1iii | 3.6506 (9) |
Cs1—H2Ai | 3.8388 | C1—H1A | 0.9800 |
Cs1—H2Ciii | 3.2692 | C1—H1B | 0.9800 |
Cs1—H4A | 3.5176 | C1—H1C | 0.9800 |
Cs1—H4Biv | 3.5628 | C2—H2A | 0.9800 |
Cs1—H4B | 3.4588 | C2—H2B | 0.9800 |
Cs1—H4Civ | 3.7984 | C2—H2C | 0.9800 |
S1—Cs1v | 3.4726 (3) | C3—H3A | 0.9800 |
S1—Cs1ii | 3.6077 (3) | C3—H3B | 0.9800 |
S1—P1 | 2.0003 (4) | C3—H3C | 0.9800 |
S2—Cs1iii | 3.4667 (3) | C4—H4A | 0.9800 |
S2—P2 | 1.9869 (4) | C4—H4B | 0.9800 |
P1—N1 | 1.6075 (10) | C4—H4C | 0.9800 |
P1—C1 | 1.8052 (11) | ||
S1—Cs1—S1i | 153.276 (4) | H4B—Cs1—H4Civ | 69.4 |
S1—Cs1—S1ii | 86.999 (7) | H4Civ—Cs1—H2Ai | 109.6 |
S1i—Cs1—S1ii | 89.749 (6) | Cs1v—S1—Cs1ii | 107.659 (7) |
S1—Cs1—S2iii | 92.185 (7) | Cs1—S1—Cs1v | 135.252 (9) |
S1ii—Cs1—N1iii | 144.629 (15) | Cs1—S1—Cs1ii | 93.001 (7) |
S1i—Cs1—N1iii | 104.024 (15) | P1—S1—Cs1ii | 117.081 (14) |
S1—Cs1—N1iii | 93.707 (15) | P1—S1—Cs1 | 89.211 (12) |
S1i—Cs1—H2Ai | 52.3 | P1—S1—Cs1v | 113.760 (14) |
S1—Cs1—H2Ai | 147.1 | P2—S2—Cs1iii | 89.743 (12) |
S1ii—Cs1—H2Ai | 68.5 | S1—P1—Cs1 | 60.397 (11) |
S1—Cs1—H4A | 101.4 | N1—P1—Cs1 | 51.35 (3) |
S1i—Cs1—H4A | 55.0 | N1—P1—S1 | 110.64 (4) |
S1—Cs1—H4Biv | 102.3 | N1—P1—C1 | 111.59 (5) |
S1—Cs1—H4B | 102.3 | N1—P1—C2 | 112.81 (5) |
S1i—Cs1—H4Biv | 53.8 | C1—P1—Cs1 | 118.41 (4) |
S1ii—Cs1—H4Civ | 69.8 | C1—P1—S1 | 109.40 (4) |
S1i—Cs1—H4Civ | 74.0 | C1—P1—C2 | 102.71 (6) |
S1—Cs1—H4Civ | 80.0 | C2—P1—Cs1 | 138.82 (4) |
S2iii—Cs1—S1i | 114.494 (7) | C2—P1—S1 | 109.39 (4) |
S2iii—Cs1—S1ii | 93.387 (7) | S2—P2—Cs1iii | 60.375 (11) |
S2iii—Cs1—N1iii | 51.243 (15) | N1—P2—Cs1iii | 66.26 (3) |
S2iii—Cs1—H2Ai | 68.7 | N1—P2—S2 | 117.15 (4) |
S2iii—Cs1—H4A | 153.9 | N1—P2—C3 | 112.20 (5) |
S2iii—Cs1—H4Biv | 148.8 | N1—P2—C4 | 103.48 (5) |
S2iii—Cs1—H4Civ | 161.7 | C3—P2—Cs1iii | 162.13 (4) |
N1—Cs1—S1 | 53.074 (17) | C3—P2—S2 | 108.87 (4) |
N1—Cs1—S1i | 105.154 (17) | C3—P2—C4 | 104.09 (6) |
N1—Cs1—S1ii | 114.158 (17) | C4—P2—Cs1iii | 93.37 (4) |
N1—Cs1—S2iii | 131.503 (18) | C4—P2—S2 | 110.14 (4) |
N1—Cs1—N1iii | 93.76 (2) | Cs1—N1—Cs1iii | 86.24 (2) |
N1iii—Cs1—H2Ai | 94.3 | P1—N1—Cs1iii | 100.76 (4) |
N1—Cs1—H2Ai | 157.3 | P1—N1—Cs1 | 105.60 (4) |
N1—Cs1—H2Ciii | 121.1 | P1—N1—P2 | 132.16 (6) |
N1—Cs1—H4A | 50.2 | P2—N1—Cs1 | 121.68 (4) |
N1—Cs1—H4Biv | 78.0 | P2—N1—Cs1iii | 89.80 (4) |
N1—Cs1—H4B | 50.7 | P1—C1—H1A | 109.5 |
N1iii—Cs1—H4Civ | 145.1 | P1—C1—H1B | 109.5 |
N1—Cs1—H4Civ | 55.1 | P1—C1—H1C | 109.5 |
H2Ciii—Cs1—S1i | 55.1 | H1A—C1—H1B | 109.5 |
H2Ciii—Cs1—S1ii | 119.8 | H1A—C1—H1C | 109.5 |
H2Ciii—Cs1—S1 | 146.0 | H1B—C1—H1C | 109.5 |
H2Ciii—Cs1—S2iii | 67.4 | P1—C2—H2A | 109.5 |
H2Ciii—Cs1—N1iii | 52.3 | P1—C2—H2B | 109.5 |
H2Ciii—Cs1—H2Ai | 51.3 | P1—C2—H2C | 109.5 |
H2Ciii—Cs1—H4A | 89.6 | H2A—C2—H2B | 109.5 |
H2Ciii—Cs1—H4B | 74.0 | H2A—C2—H2C | 109.5 |
H2Ciii—Cs1—H4Biv | 109.0 | H2B—C2—H2C | 109.5 |
H2Ciii—Cs1—H4Civ | 126.8 | P2—C3—H3A | 109.5 |
H4A—Cs1—S1ii | 109.3 | P2—C3—H3B | 109.5 |
H4A—Cs1—N1iii | 105.2 | P2—C3—H3C | 109.5 |
H4A—Cs1—H2Ai | 107.2 | H3A—C3—H3B | 109.5 |
H4A—Cs1—H4Biv | 49.1 | H3A—C3—H3C | 109.5 |
H4A—Cs1—H4Civ | 44.4 | H3B—C3—H3C | 109.5 |
H4B—Cs1—S1ii | 135.7 | Cs1—C4—H4A | 63.3 |
H4B—Cs1—S1i | 62.8 | Cs1—C4—H4B | 59.7 |
H4Biv—Cs1—S1ii | 60.5 | Cs1—C4—H4C | 159.4 |
H4B—Cs1—S2iii | 128.8 | P2—C4—Cs1 | 91.05 (4) |
H4B—Cs1—N1iii | 78.7 | P2—C4—H4A | 109.5 |
H4Biv—Cs1—N1iii | 151.7 | P2—C4—H4B | 109.5 |
H4B—Cs1—H2Ai | 110.6 | P2—C4—H4C | 109.5 |
H4Biv—Cs1—H2Ai | 84.9 | H4A—C4—H4B | 109.5 |
H4B—Cs1—H4A | 26.5 | H4A—C4—H4C | 109.5 |
H4B—Cs1—H4Biv | 75.2 | H4B—C4—H4C | 109.5 |
H4Biv—Cs1—H4Civ | 24.8 |
Symmetry codes: (i) −x+1, y+1/2, −z+1/2; (ii) −x+1, −y+1, −z; (iii) −x+1, −y+1, −z+1; (iv) x, −y+3/2, z−1/2; (v) −x+1, y−1/2, −z+1/2. |
Acknowledgements
We thank Professor A. Schmidpeter for providing a sample of the salt (I).
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