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ISSN: 2056-9890

Secondary bonding in di­methyl­bis­­(morpholine-4-carbodi­thio­ato-κ2S,S′)tin(IV): crystal structure and Hirshfeld surface analysis

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aDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia, bResearch Centre for Crystalline Materials, School of Science and Technology, Sunway University, 47500 Bandar Sunway, Selangor Darul Ehsan, Malaysia, cDepartment of Chemistry, Lancaster University, Lancaster LA1 4YB, United Kingdom, dDepartment of Physics, Bhavan's Sheth R. A. College of Science, Ahmedabad, Gujarat 380 001, India, and eResearch Centre for Chemical Crystallography, School of Science and Technology, Sunway University, 47500 Bandar Sunway, Selangor Darul Ehsan, Malaysia
*Correspondence e-mail: edwardt@sunway.edu.my

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 4 May 2017; accepted 7 May 2017; online 12 May 2017)

The title compound, [Sn(CH3)2(C5H8NOS2)2], has the SnIV atom bound by two methyl groups which lie over the weaker Sn—S bonds formed by two asymmetrically chelating di­thio­carbamate ligands so that the coordination geometry is skew-trapezoidal bipyramidal. The most prominent feature of the mol­ecular packing are secondary Sn⋯S inter­actions [Sn⋯S = 3.5654 (7) Å] that lead to centrosymmetric dimers. These are connected into a three-dimensional architecture via methyl­ene-C—H⋯S and methyl-C—H⋯O(morpholino) inter­actions. The Sn⋯S inter­actions are clearly evident in the Hirshfeld surface analysis of the title compound along with a number of other inter­molecular contacts.

1. Chemical context

Both binary tin and organotin di­thio­carbamates, RnSn(S2CNRR′)m for n + m = 4, are well known to exhibit potential biological properties, e.g. anti-cancer (Ferreira et al., 2014[Ferreira, I. P., de Lima, G. M., Paniago, E. B., Rocha, W. R., Takahashi, J. A., Pinheiro, C. B. & Ardisson, J. D. (2014). Polyhedron, 79, 161-169.]), anti-fungal (Yu et al., 2014[Yu, Y., Yang, H., Wei, Z.-W. & Tang, L.-F. (2014). Heteroat. Chem. 25, 274-281.]) and anti-microbial (Ferreira et al., 2012[Ferreira, I. P., de Lima, G. M., Paniago, E. B., Rocha, W. R., Takahashi, J. A., Pinheiro, C. B. & Ardisson, J. D. (2012). Eur. J. Med. Chem. 58, 493-503.]), as well to serve as useful mol­ecular precursors for the generation of `SnS' nanomaterials (Kevin et al., 2015[Kevin, P., Lewis, D. J., Raftery, J., Malik, M. A. & O'Brien, P. (2015). J. Cryst. Growth, 415, 93-99.]). The structural chemistry of this class of compound has also attracted considerable inter­est over the years owing to the occurrence of significant structural diversity observed in seemingly closely related compounds (Tiekink, 2008[Tiekink, E. R. T. (2008). Appl. Organomet. Chem. 22, 533-550.]). As a case in point and related to the title compound, [Sn(CH3)2(C5H8NOS2)2] (I)[link], reported herein, are the variations in mol­ecular structure observed for the diorganotin bis­(di­thio­carbamate)s as discussed in the recent literature (Muthalib et al., 2014[Muthalib, A. F. A., Baba, I., Khaledi, H., Ali, H. M. & Tiekink, E. R. T. (2014). Z. Kristallogr. 229, 39-46.]; Mohamad et al., 2016[Mohamad, R., Awang, N., Jotani, M. M. & Tiekink, E. R. T. (2016). Acta Cryst. E72, 1130-1137.], 2017[Mohamad, R., Awang, N., Kamaludin, N. F., Jotani, M. M. & Tiekink, E. R. T. (2017). Acta Cryst. E73, 260-265.]). These R2Sn(S2CNRR')2 structures are known to adopt four distinct coordination geometries with the majority being skew-trapezoidal bipyramidal or octa­hedral, each based on C2S4 donor sets. Fewer examples are known for five-coordinate, trigonal–bipyramidal species, e.g. (t-Bu)2Sn(S2CNMe2)2 in which one di­thio­carbamate ligand is monodentate (Kim et al., 1987[Kim, K., Ibers, J. A., Jung, O.-S. & Sohn, Y. S. (1987). Acta Cryst. C43, 2317-2319.]), and seven-coordinate, penta­gonal–bipyramidal, e.g. [MeOC(=O)CH2CH2]2Sn(S2CNMe)2 where the carbonyl-O atom of one Sn-bound organic substituent is also coordinating the tin atom (Ng et al., 1989[Ng, S. W., Wei, C., Kumar Das, V. G., Jameson, G. B. & Butcher, R. J. (1989). J. Organomet. Chem. 365, 75-82.]). This last example is of inter­est as it demonstrates tin may in fact increase its coordination number by additional inter­actions. When additional inter­actions of this type occur inter­molecularly, they are termed secondary bonding or tetrel bonding as a Group IV element, tin, is involved (Alcock, 1972[Alcock, N. W. (1972). Adv. Inorg. Chem. Radiochem. 15, 1-58.]; Marín-Luna et al., 2016[Marín-Luna, M., Alkorta, I. & Elguero, J. (2016). J. Phys. Chem. A, 120, 648-656.]; Tiekink, 2017[Tiekink, E. R. T. (2017). Coord. Chem. Rev. https://dx.doi.org/10.1016/j.ccr.2017.01.009.]). Generally, secondary inter­actions do not occur for R2Sn(S2CNRR')2 structures as the strong chelating ability of the di­thio­carbamate ligand reduces the Lewis acidity of the tin atom. However, in (I)[link] such secondary Sn⋯S inter­actions do in fact occur. In a continuation of work in this area, herein the synthesis and crystal and mol­ecular structures of (I)[link] are described as well as an analysis of the Hirshfeld surface with a particular emphasis on investigating the role of the secondary Sn⋯S inter­action.

[Scheme 1]

2. Structural commentary

The SnIV atom in the title compound (I)[link], Fig. 1[link], adopts one of the common coordination geometries found for R2Sn(S2CNRR')2 mol­ecules, i.e. skew-trapezoidal bipyramidal rather than octa­hedral (Tiekink, 2008[Tiekink, E. R. T. (2008). Appl. Organomet. Chem. 22, 533-550.]). This arises as the chelating di­thio­carbamate ligands have asymmetric Sn—S bond lengths, Table 1[link]. The values of Δ(Sn—S) = [d(Sn—Slong) − d(Sn—Sshort] for the S1- and S3-di­thio­carbamate ligands are approximately the same at 0.35 Å, but the comparable bonds formed by the S3-di­thio­carbamate ligand are systematically longer than those formed by the S1-di­thio­carbamate ligand by approximately 0.02 Å, Table 1[link]. The asymmetry in the Sn—S bond lengths is reflected in the disparity in the associated C—S bond lengths with the sulfur atom forming the longer Sn—S bond being involved in the significantly shorter, by approx­imately 0.05 Å, C—S bond, Table 1[link]. Consistent with the skew-trapezoidal bipyramidal geometry about the SnIV atom, the Sn-bound methyl substituents are directed over the longer Sn—S bonds and define an angle of 148.24 (11)° at the tin atom. The angle subtended at the tin atom by the strongly bound sulfur atoms of 85.878 (19)° is significantly less than that formed by the weakly bound sulfur atoms, i.e. 143.066 (18)°, and is largely responsible for the formation of the skew-trapezoidal plane about the tin atom.

Table 1
Selected geometric parameters (Å, °)

Sn—S1 2.5429 (6) Sn—C12 2.111 (3)
Sn—S2 2.8923 (6) C1—S1 1.747 (3)
Sn—S3 2.5649 (7) C1—S2 1.702 (3)
Sn—S4 2.9137 (6) C6—S3 1.750 (3)
Sn—C11 2.132 (3) C6—S4 1.697 (3)
       
S1—Sn—S2 65.935 (19) S2—Sn—C12 84.93 (8)
S1—Sn—S3 85.878 (19) S3—Sn—S4 65.137 (18)
S1—Sn—S4 150.95 (2) S3—Sn—C12 102.37 (8)
S1—Sn—C11 99.49 (8) S3—Sn—C11 99.28 (8)
S1—Sn—C12 104.96 (8) S4—Sn—C11 84.20 (8)
S2—Sn—S3 151.798 (18) S4—Sn—C12 84.15 (7)
S2—Sn—S4 143.066 (18) C11—Sn—C12 148.24 (11)
S2—Sn—C11 86.87 (8)    
[Figure 1]
Figure 1
The mol­ecular structure of (I)[link], showing the atom-labelling scheme and displacement ellipsoids at the 50% probability level.

3. Supra­molecular features

An inter­esting feature of the mol­ecular packing in (I)[link] is the formation of a supra­molecular dimer sustained by Sn⋯S secondary inter­actions, as shown in Fig. 2[link]a, where two long edges of the translationally displaced trapezoidal planes approach each other to form the inter­actions. Here, Sn⋯S4i is 3.5654 (7) Å, which is approximately 0.4 Å shorter than the sum of the van der Waals radii of Sn and S of 3.97 Å (Bondi, 1964[Bondi, A. (1964). J. Phys. Chem. 68, 441-451.]); symmetry operation (i): 1 − x, 1 − y, 1 − z. Connections between the dimeric aggregates are of the type methyl­ene-C—H⋯S and methyl-C—H⋯O(morpholino), Table 2[link], and these inter­actions combine to generate a three-dimensional architecture, Fig. 2[link]b.

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C10—H10A⋯S1i 0.99 2.86 3.809 (3) 161
C12—H12C⋯O1ii 0.98 2.47 3.399 (4) 158
Symmetry codes: (i) [x-{\script{3\over 2}}, -y-{\script{1\over 2}}, z-{\script{3\over 2}}]; (ii) -x+2, -y+1, -z+1.
[Figure 2]
Figure 2
The mol­ecular packing in (I)[link], showing (a) a supra­molecular dimer sustained by Sn⋯S secondary inter­actions shown as black dashed lines and (b) a view of the unit-cell contents in projection down the a axis. The C—H⋯S and C—H⋯O inter­actions are shown as orange and blue dashed lines, respectively.

4. Hirshfeld surface analysis

The Hirshfeld surfaces calculated on the structure of (I)[link] also provide insight into the supra­molecular association through secondary Sn⋯S, S⋯S and other contacts, and was performed as per recent publications on related organotin di­thio­carbamate structures (Mohamad et al., 2017[Mohamad, R., Awang, N., Kamaludin, N. F., Jotani, M. M. & Tiekink, E. R. T. (2017). Acta Cryst. E73, 260-265.], 2016[Mohamad, R., Awang, N., Jotani, M. M. & Tiekink, E. R. T. (2016). Acta Cryst. E72, 1130-1137.]). The broad, bright-red spots appearing near the Sn and S4 atoms on the Hirshfeld surfaces mapped over dnorm in Fig. 3[link]a indicate the formation of the supra­molecular dimer through secondary Sn⋯S contacts. On the Hirshfeld surface mapped over electrostatic potential in Fig. 4[link], these inter­actions are represented by the blue and red regions around these atoms, respectively. The faint-red spot appearing between the above bright-red spots near the S4 atom indicates the short inter-atomic S⋯S contact, Table 3[link], between S4 atoms lying on diagonally opposite vertices of a parallelogram formed by symmetry-related Sn and S4 atoms, Fig. 5[link]a. The pair of bright-red spots appearing near the methyl-H12C and morpholine-O1 atoms in Fig. 3[link]b represent the respective donor and acceptor atoms of the C12—H⋯O1 inter­action. The comparatively weaker methyl­ene-C10—H⋯S1 inter­action is viewed as a pair of faint-red spots near these atoms in Fig. 3[link]b. It is important to note from the immediate environments about a reference mol­ecule within dnorm-mapped Hirshfeld surfaces highlighting inter­molecular inter­actions in Fig. 5[link] that the secondary Sn⋯S and S⋯S contacts are on one side of the Hirshfeld surface while the atoms participating in C—H⋯O and C—H⋯S inter­actions are on the other side of the surface.

Table 3
Summary of short inter-atomic contacts (Å) in (I)

Contact distance symmetry operation
S4⋯S4 3.5835 (10) 1 − x, 1 − y, −z
S2⋯H12B 2.99 [{3\over 2}] − x, [{1\over 2}] + y, [{1\over 2}] − z
S3⋯H5B 2.94 1 − x, 1 − y, 1 − z
S4⋯H11C 2.94 1 − x, 1 − y, − z
O2⋯H2A 2.63 [{1\over 2}] − x, −[{1\over 2}] + y, [{1\over 2}] − z
O2⋯H5B 2.70 [{1\over 2}] − x, −[{1\over 2}] + y, [{1\over 2}] − z
C1⋯H3A 2.88 2 − x, 1 − y, 1 − z
C3⋯H12C 2.86 2 − x, 1 − y, 1 − z
H2A⋯H11C 2.36 [{1\over 2}] + x, [{3\over 2}] − y, [{1\over 2}] + z
[Figure 3]
Figure 3
Two views of the Hirshfeld surface for (I)[link] plotted over dnorm in the range −0.050 to 1.780 au.
[Figure 4]
Figure 4
A view of Hirshfeld surface for (I)[link] mapped over the calculated electrostatic potential in the range −0.053 to +0.078 au. The red and blue regions represent negative and positive electrostatic potentials, respectively.
[Figure 5]
Figure 5
Views of Hirshfeld surfaces mapped over dnorm about a reference mol­ecule showing (a) secondary Sn⋯S/S⋯Sn and S⋯S contacts by sky-blue and red dashed lines, respectively and (b) C—H⋯O and C—H⋯S inter­actions by black dashed lines

The overall two-dimensional fingerprint plot, Fig. 6[link]a, and those delineated into H⋯H, S⋯H/H⋯S, O⋯H/H⋯O, C⋯H/H⋯C, N⋯H/H⋯N, Sn⋯S/S⋯Sn and S⋯S contacts (McKinnon et al., 2007[McKinnon, J. J., Jayatilaka, D. & Spackman, M. A. (2007). Chem. Commun. pp. 3814-3816.]) are illustrated in Fig. 6[link]bh, respectively; the relative contributions from the various contacts to the Hirshfeld surfaces are summarized in Table 4[link].

Table 4
Percentage contributions of inter-atomic contacts to the Hirshfeld surfaces for (I)

Contact percentage contribution
H⋯H 56.8
S⋯H/H⋯S 27.2
O⋯H/H⋯O 9.9
C⋯/H⋯C 4.0
N⋯H/H⋯N 1.1
Sn⋯S/S⋯Sn 0.5
S⋯S 0.5
[Figure 6]
Figure 6
(a) The full two-dimensional fingerprint plot for (I)[link] and fingerprint plots delineated into (b) H⋯H, (c) S⋯H/H⋯S, (d) O⋯H/H⋯O, (e) C⋯H/H⋯C, (f) N⋯H/H⋯H, (g) Sn⋯S/S⋯Sn and (h) S⋯S contacts.

In the fingerprint plot delineated into H⋯H contacts, Fig. 6[link]b, the points forming the single short peak at de + di < 2.4 Å are indicative of the short inter-atomic H⋯H contact listed in Table 3[link]. The involvement of S1 in the C—H⋯S inter­action and other sulfur atoms in short inter-atomic S⋯H/H⋯S contacts, Table 3[link], results in an overall 27.2% contribution to the Hirshfeld surface. In the fingerprint plot delineated into S⋯H/H⋯S contacts, Fig. 6[link]c, they appear as overlapping donor–acceptor regions showing corners and a pair of greenish regions of greater intensity having short spikes at de + di ∼ 2.9 Å. The C—H⋯O contact is evident from the two-dimensional fingerprint plot delineated into O⋯H/H⋯O contacts, Fig. 6[link]d, as the pair of tips at de + di ∼ 2.5 Å in the forceps-like distribution. The short inter-atomic O⋯H/H⋯O contacts, Table 3[link], in the plot appear as faint-green points in a slightly scattered form emanating from de + di ∼ 2.9 Å. The pair of short spikes at de + di < 2.9 Å overlapping on the well separated donor and acceptor regions in the fingerprint plot delineated into C⋯H/H⋯C contacts, Fig. 6[link]e, indicate the influence of short inter-atomic C⋯H/H⋯C contacts, Table 3[link]. The presence of secondary Sn⋯S and short S⋯S contacts in the structure is also confirmed from the respective plots through the distribution of points as a pair of thin line segments, Fig. 6[link]f, and a triangle, Fig. 6[link]g, respectively, having minimum de + di distances at around 3.5 Å and 3.6 Å, respectively. The 1.1% contribution from N⋯H/H⋯N contacts, Fig. 6[link]h, to the Hirshfeld surface reflects an insignificant influence upon the mol­ecular packing as the inter-atomic separations are greater than the sum of the respective van der Waals radii.

5. Database survey

The Cambridge Crystallographic Database (Groom et al., 2016[Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171-179.]) contains over 110 mol­ecules of the general formula R2Sn(S2CNRR')2. Of these, 12 feature secondary Sn⋯S inter­actions which, with (I)[link], means approximately 10% of all R2Sn(S2CNRR')2 structures have Sn⋯S secondary inter­actions. Selected geometric details for the 13 structures are collated in Table 5[link]. The Sn⋯S inter­actions assemble mol­ecules in their crystals into three distinct structural motifs. The common motif, A, is a dimeric aggregate disposed about a centre of inversion, as is in (I)[link], and is found in the majority of crystals, i.e. nine. This motif is illustrated in Fig. 7[link]a for (PhCH2)2Sn(S2CNEt2)2 (Yin et al., 2003[Yin, H. D., Wang, C.-H., Wang, Y. & Ma, C.-L. (2003). Chin. J. Chem. 21, 356-360.]). A second zero-dimensional motif, B, is also known and is readily related to A. In the structure of Me2Sn(S2CN(Et)CH2C6H4N-4)2 (Barba et al., 2012[Barba, V., Arenaza, B., Guerrero, J. & Reyes, R. (2012). Heteroat. Chem. 23, 422-428.]), two independent mol­ecules comprise the asymmetric unit. One of these self-assembles about a centre of inversion as for motif A. The nitro­gen atom of each pendent 4-pyridyl group of the dimeric aggregate thus assembled inter­acts with the tin atom of the second independent mol­ecule via a Sn⋯N inter­action to form the four-mol­ecule aggregate shown in Fig. 7[link]b. The final three mol­ecules are binuclear owing to the presence of bis­(di­thio­carbamate) ligands and self-assemble into supra­molecular chains. In {Me2SnS2CN(CH2Ph)CH2(1,3-C6H3)CH2(PhCH2)NCS2SnMe2}2 (Santacruz-Juárez et al., 2008[Santacruz-Juárez, E., Cruz-Huerta, J., Hernández-Ahuactzi, I. F., Reyes-Martínez, R., Tlahuext, H., Morales-Rojas, H. & Höpfl, H. (2008). Inorg. Chem. 47, 9804-9812.]), the mol­ecule is situated about a centre of inversion and each tin atom forms an Sn⋯S contact to generate a linear, supra­molecular chain, motif C, Fig. 7[link]c. A variation is seen in the crystal of Me2SnS2CN(CH2CH2-i-Pr)CH2(1,3-C6H3)CH2(PhCH2)NCS2SnMe2}2, where there are two independent, centrosymmetric mol­ecules in the asymmetric unit. Here, the resulting supra­molecular chain is twisted (Santacruz-Juárez et al., 2008[Santacruz-Juárez, E., Cruz-Huerta, J., Hernández-Ahuactzi, I. F., Reyes-Martínez, R., Tlahuext, H., Morales-Rojas, H. & Höpfl, H. (2008). Inorg. Chem. 47, 9804-9812.]) and is assigned as motif C′.

Table 5
Summary of Sn—S, Sn⋯S distances (Å) in R2Sn(S2CNRR′)2 structures featuring secondary Sn⋯S inter­actions

R R, R Sn—Sshort, Sn—Slong Sn⋯S motif Reference
Me Et, Et 2.5174 (18), 2.961 (3); 2.528 (2), 2.9162 (17) 3.853 (2) A Morris & Schlemper (1979[Morris, J. S. & Schlemper, E. O. (1979). J. Cryst. Mol. Struct. 9, 13-31.])
Me (CH2CH2)Me 2.5367 (14), 2.9171 (16); 2.5577 (15), 2.8953 (16) 3.6978 (18) A Zia-ur-Rehman et al. (2007[Zia-ur-Rehman, Shahzadi, S., Ali, S. & Jin, G.-X. (2007). Turk. J. Chem. 31, 435-442.])
Me (CH2CH2)O 2.5429 (6), 2.8923 (6); 2.5649 (7), 2.9137 (6) 3.5654 (7) A this work
C(H)=CH2 Cy 2.514 (5), 2.914 (4); 2.536 (4), 2.914 (4) 3.662 (5) A Hall & Tiekink (1998[Hall, V. J. & Tiekink, E. R. T. (1998). Main Group Met. Chem. 21, 245-254.])
CH2Ph Et, Et 2.5310 (11), 2.8940 (11); 2.5396 (10), 2.9109 (11) 3.8161 (12) A Yin et al. (2003[Yin, H. D., Wang, C.-H., Wang, Y. & Ma, C.-L. (2003). Chin. J. Chem. 21, 356-360.])
CH2PhCl-2 (CH2CH2)NMe 2.5401 (13), 2.8050 (13); 2.5675 (13), 2.8675 (12) 3.9071 (13) A Yin & Xue (2005a[Yin, H. D. & Xue, S. C. (2005a). Appl. Organomet. Chem. 19, 194.])
CH2PhCl-3a (CH2CH2)NEt 2.520 (3), 2.840 (3); 2.556 (2), 2.893 (3) 3.638 (3) A Xue et al. (2005[Xue, S., Yin, H., Wang, Q. & Wang, D. (2005). Heteroat. Chem. 16, 271-277.])
CH2PhCl-4 (CH2CH2)NMe 2.534 (2), 2.968 (3); 2.550 (2), 2.858 (3) 3.765 (3) A Yin & Xue (2005b[Yin, H. D. & Xue, S. C. (2005b). Appl. Organomet. Chem. 19, 187.])
CH2PhCN-4 Et, Et 2.524 (3), 2.885 (3); 2.537 (2), 2.879 (2) 3.821 (3) A Yin & Xue (2006[Yin, H. D. & Xue, S. C. (2006). Appl. Organomet. Chem. 20, 283-289.])
Meb Et; CH2Ph 2.543 (2), 2.943 (2); 2.549 (2), 2.909 (2) 3.724 (3) B Barba et al. (2012[Barba, V., Arenaza, B., Guerrero, J. & Reyes, R. (2012). Heteroat. Chem. 23, 422-428.])
    2.579 (2), 2.842 (2); 2.609 (2), 3.003 (2) 2.978 (5)c    
Med CH2Ph, 0.5(1,3-CH2C6H4CH2) 2.5086 (13), 2.8791 (15); 2.5217 (14), 3.1510 (16) 3.9641 (15) C Santacruz-Juárez et al. (2008[Santacruz-Juárez, E., Cruz-Huerta, J., Hernández-Ahuactzi, I. F., Reyes-Martínez, R., Tlahuext, H., Morales-Rojas, H. & Höpfl, H. (2008). Inorg. Chem. 47, 9804-9812.])
Med,e bi­cyclo­[2.2.1]hept-2yl, 0.5(CH2)4 2.5179 (12), 2.9015 (13); 2.5321 (12), 2.9600 (13) 3.9453 (14) C Rojas-León et al. (2012[Rojas-León, I., Guerrero-Alvarez, J. A., Hernández-Paredes, J. & Höpfl, H. (2012). Chem. Commun. 48, 401-403.])
Mef (CH2)2iPr, 0.5(1,3-CH2C6H4CH2) 2.5319 (18), 2.8855 (18); 2.5356 (17), 2.9663 (19) 4.0480 (19) C Santacruz-Juárez et al. (2008[Santacruz-Juárez, E., Cruz-Huerta, J., Hernández-Ahuactzi, I. F., Reyes-Martínez, R., Tlahuext, H., Morales-Rojas, H. & Höpfl, H. (2008). Inorg. Chem. 47, 9804-9812.])
    2.5306 (17), 2.9492 (19); 2.5402 (19), 2.9633 (19) 3.7050 (17)    
Notes: (a) piperazine mono-solvate; (b) two mol­ecules in the asymmetric unit; (c) Sn⋯N secondary inter­action; (d) the binuclear mol­ecule is located about a centre of inversion; (e) CDCl3 di-solvate per binuclear entity; (f) two mol­ecules in the asymmetric unit with each being located about a centre of inversion.
[Figure 7]
Figure 7
Supra­molecular aggregation sustained by secondary Sn⋯S inter­actions (black dashed lines) leading to (a) dimeric aggregates in (PhCH2)2Sn(S2CNEt2)2, (b) four-mol­ecule aggregates in Me2Sn(S2CN(Et)CH2C6H4N-4)2 and (c) linear supra­molecular chain in {Me2SnS2CN(CH2Ph)CH2(1,3-C6H3)CH2(PhCH2)NCS2SnMe2}2.

The common feature of all motifs listed in Table 5[link] is that it is one of the weakly bound sulfur atoms that forms the secondary Sn⋯S inter­action. Further, the tin-bound groups are relatively sterically unencumbered, allowing for the close approach of sulfur donors to the tin atoms. There are no geometric correlations. However, reflecting the weak nature of these inter­actions, the sulfur atom forming the Sn⋯S contact does not necessarily form the weaker of the Sn—Slong inter­actions in each mol­ecule. The range of Sn⋯S distances spans nearly 0.5 Å but, again, no correlations between these distances and the Slong—Sn—Slong angles is apparent, i.e. it might be expected that the shorter Sn⋯S inter­actions would result in wider Slong—Sn—Slong angles.

6. Synthesis and crystallization

All chemicals and solvents were used as purchased without purification, and all reactions were carried out under ambient conditions. The melting point was determined using an Electrothermal digital melting point apparatus and was uncorrected. The IR spectrum for (I)[link] was obtained on a Perkin Elmer Spectrum 400 FT Mid-IR/Far-IR spectrophotometer in the range 4000 to 400 cm−1. The 1H NMR spectrum was recorded at room temperature in CDCl3 solution on a Jeol ECA 400 MHz FT–NMR spectrometer.

Sodium morpholine­dithio­carbamate (prepared from the reaction between carbon di­sulfide and morpholine (Merck) in the presence of sodium hydroxide; 1.0 mmol, 0.185 g) in methanol (20 ml) was added to di­methyl­tin dichloride (Merck, 1.0 mmol, 0.219 g) in methanol (10 ml). The resulting mixture was stirred and refluxed for 2 h. The filtrate was evaporated until an off-white precipitate was obtained. The precipitate was recrystallized from methanol solution by slow evaporation to yield colourless prisms. Yield: 0.305 g, 64.4%; m.p.: 448 K. IR (cm−1): 1465(s), 1423(s) ν(C—N), 1222(s) ν(C—O), 1110(m), 994(s) ν(C—S), 541(m) ν(Sn—C) cm−1. 1H NMR (CDCl3): 4.18 (s, 8H, CH2O), 3.77 (s, 8H, NCH2), 1.54 (s, 6H, -CH3).

7. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 6[link]. Carbon-bound H atoms were placed in calculated positions (C—H = 0.98–0.99 Å) and were included in the refinement in the riding-model approximation, with Uiso(H) set to 1.2–1.5Ueq(C). Owing to poor agreement, one reflection, i.e. ([\overline{12}] 1 5), was omitted from the final cycles of refinement.

Table 6
Experimental details

Crystal data
Chemical formula [Sn(CH3)2(C5H8NOS2)2]
Mr 473.24
Crystal system, space group Monoclinic, P21/n
Temperature (K) 100
a, b, c (Å) 10.1472 (1), 13.6653 (1), 13.8122 (1)
β (°) 104.959 (1)
V3) 1850.36 (3)
Z 4
Radiation type Cu Kα
μ (mm−1) 15.25
Crystal size (mm) 0.24 × 0.09 × 0.06
 
Data collection
Diffractometer Agilent SuperNova, Dual, Cu at zero, AtlasS2
Absorption correction Gaussian (CrysAlis PRO; Rigaku Oxford Diffraction, 2015[Rigaku Oxford Diffraction (2015). CrysAlis PRO. Agilent Technologies Inc., Santa Clara, CA, USA.])
Tmin, Tmax 0.242, 0.759
No. of measured, independent and observed [I > 2σ(I)] reflections 19588, 3865, 3809
Rint 0.031
(sin θ/λ)max−1) 0.631
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.024, 0.065, 1.07
No. of reflections 3865
No. of parameters 192
H-atom treatment H-atom parameters constrained
Δρmax, Δρmin (e Å−3) 0.45, −0.50
Computer programs: CrysAlis PRO (Rigaku Oxford Diffraction, 2015[Rigaku Oxford Diffraction (2015). CrysAlis PRO. Agilent Technologies Inc., Santa Clara, CA, USA.]), SHELXS (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]), SHELXL2014 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]), ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]), DIAMOND (Brandenburg, 2006[Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.]) and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Computing details top

Data collection: CrysAlis PRO (Rigaku Oxford Diffraction, 2015); cell refinement: CrysAlis PRO (Rigaku Oxford Diffraction, 2015); data reduction: CrysAlis PRO (Rigaku Oxford Diffraction, 2015); program(s) used to solve structure: SHELXS (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Dimethylbis(morpholine-4-carbodithioato-κ2S,S')tin(IV) top
Crystal data top
[Sn(CH3)2(C5H8NOS2)2]F(000) = 952
Mr = 473.24Dx = 1.699 Mg m3
Monoclinic, P21/nCu Kα radiation, λ = 1.54184 Å
a = 10.1472 (1) ÅCell parameters from 14936 reflections
b = 13.6653 (1) Åθ = 3.2–76.6°
c = 13.8122 (1) ŵ = 15.25 mm1
β = 104.959 (1)°T = 100 K
V = 1850.36 (3) Å3Prism, colourless
Z = 40.24 × 0.09 × 0.06 mm
Data collection top
Agilent SuperNova, Dual, Cu at zero, AtlasS2
diffractometer
3865 independent reflections
Radiation source: micro-focus sealed X-ray tube, SuperNova (Cu) X-ray Source3809 reflections with I > 2σ(I)
Mirror monochromatorRint = 0.031
ω scansθmax = 76.8°, θmin = 4.6°
Absorption correction: gaussian
(CrysAlis PRO; Rigaku Oxford Diffraction, 2015)
h = 1212
Tmin = 0.242, Tmax = 0.759k = 1317
19588 measured reflectionsl = 1717
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.024H-atom parameters constrained
wR(F2) = 0.065 w = 1/[σ2(Fo2) + (0.0322P)2 + 2.5554P]
where P = (Fo2 + 2Fc2)/3
S = 1.07(Δ/σ)max = 0.001
3865 reflectionsΔρmax = 0.45 e Å3
192 parametersΔρmin = 0.50 e Å3
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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Sn0.54609 (2)0.47196 (2)0.20083 (2)0.01811 (6)
S10.60114 (7)0.47340 (5)0.39117 (5)0.02266 (14)
S20.76105 (7)0.60660 (4)0.29478 (4)0.02164 (13)
S30.36959 (7)0.34005 (5)0.20926 (4)0.02368 (13)
S40.38512 (7)0.40224 (5)0.00694 (4)0.02491 (14)
O10.9722 (2)0.62761 (17)0.68544 (15)0.0315 (4)
O20.1073 (2)0.28893 (17)0.02186 (16)0.0334 (5)
N10.7980 (2)0.59004 (16)0.49256 (16)0.0216 (4)
N20.1802 (2)0.29886 (17)0.04134 (16)0.0235 (5)
C10.7294 (3)0.56096 (18)0.40120 (18)0.0188 (5)
C20.8983 (3)0.6702 (2)0.5084 (2)0.0245 (5)
H2A0.85430.73210.52050.029*
H2B0.93180.67860.44770.029*
C31.0169 (3)0.6474 (2)0.5975 (2)0.0294 (6)
H3A1.06700.58990.58170.035*
H3B1.08050.70360.61030.035*
C40.8853 (3)0.5444 (2)0.6688 (2)0.0285 (6)
H4A0.85790.52900.73090.034*
H4B0.93550.48740.65220.034*
C50.7594 (3)0.5622 (2)0.58459 (19)0.0253 (5)
H5A0.70310.50210.57220.030*
H5B0.70440.61510.60370.030*
C60.2990 (3)0.34278 (18)0.07953 (18)0.0202 (5)
C70.1020 (3)0.2459 (2)0.1005 (2)0.0267 (6)
H7A0.14940.25020.17260.032*
H7B0.09430.17600.08100.032*
C80.0379 (3)0.2905 (2)0.0819 (2)0.0310 (6)
H8A0.09190.25390.12010.037*
H8B0.02960.35900.10610.037*
C90.0330 (3)0.3430 (2)0.0777 (2)0.0303 (6)
H9A0.02610.41200.05510.036*
H9B0.08290.34180.14950.036*
C100.1087 (3)0.3021 (2)0.06570 (19)0.0249 (5)
H10A0.10280.23540.09450.030*
H10B0.15990.34390.10200.030*
C110.4147 (3)0.5961 (2)0.1692 (2)0.0260 (5)
H11A0.45730.65130.21100.039*
H11B0.32750.58030.18370.039*
H11C0.39870.61370.09830.039*
C120.7041 (3)0.38945 (19)0.1667 (2)0.0242 (5)
H12A0.71540.40950.10120.036*
H12B0.68090.31970.16500.036*
H12C0.78940.40080.21810.036*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Sn0.02190 (10)0.01935 (10)0.01260 (9)0.00090 (6)0.00357 (6)0.00052 (5)
S10.0275 (3)0.0258 (3)0.0140 (3)0.0074 (2)0.0041 (2)0.0009 (2)
S20.0290 (3)0.0213 (3)0.0154 (3)0.0032 (2)0.0069 (2)0.0006 (2)
S30.0290 (3)0.0286 (3)0.0117 (3)0.0060 (2)0.0022 (2)0.0025 (2)
S40.0282 (3)0.0332 (3)0.0131 (3)0.0068 (3)0.0051 (2)0.0014 (2)
O10.0294 (10)0.0400 (11)0.0208 (9)0.0022 (9)0.0013 (8)0.0006 (8)
O20.0246 (10)0.0416 (12)0.0313 (11)0.0046 (9)0.0025 (8)0.0013 (9)
N10.0257 (11)0.0236 (10)0.0149 (10)0.0024 (9)0.0041 (8)0.0016 (8)
N20.0258 (11)0.0271 (11)0.0163 (10)0.0043 (9)0.0033 (9)0.0012 (9)
C10.0234 (12)0.0153 (11)0.0168 (11)0.0006 (9)0.0036 (9)0.0018 (9)
C20.0249 (13)0.0256 (13)0.0201 (12)0.0042 (10)0.0007 (10)0.0027 (10)
C30.0248 (13)0.0337 (15)0.0273 (14)0.0014 (11)0.0023 (11)0.0002 (12)
C40.0323 (15)0.0301 (14)0.0208 (13)0.0020 (12)0.0029 (11)0.0029 (11)
C50.0291 (14)0.0320 (14)0.0140 (11)0.0044 (11)0.0040 (10)0.0019 (10)
C60.0233 (12)0.0204 (11)0.0160 (11)0.0013 (9)0.0037 (9)0.0002 (9)
C70.0293 (14)0.0290 (13)0.0212 (12)0.0091 (11)0.0053 (11)0.0022 (11)
C80.0284 (14)0.0373 (15)0.0278 (14)0.0074 (12)0.0083 (11)0.0038 (12)
C90.0300 (14)0.0314 (15)0.0253 (13)0.0019 (12)0.0002 (11)0.0020 (11)
C100.0265 (13)0.0295 (13)0.0161 (12)0.0074 (11)0.0010 (10)0.0027 (10)
C110.0279 (13)0.0244 (13)0.0260 (13)0.0111 (11)0.0074 (11)0.0042 (10)
C120.0264 (13)0.0222 (12)0.0228 (12)0.0052 (10)0.0043 (10)0.0042 (10)
Geometric parameters (Å, º) top
Sn—S12.5429 (6)C3—H3A0.9900
Sn—S22.8923 (6)C3—H3B0.9900
Sn—S32.5649 (7)C4—C51.509 (4)
Sn—S42.9137 (6)C4—H4A0.9900
Sn—C112.132 (3)C4—H4B0.9900
Sn—C122.111 (3)C5—H5A0.9900
C1—S11.747 (3)C5—H5B0.9900
C1—S21.702 (3)C7—C81.505 (4)
C6—S31.750 (3)C7—H7A0.9900
C6—S41.697 (3)C7—H7B0.9900
O1—C41.421 (4)C8—H8A0.9900
O1—C31.428 (4)C8—H8B0.9900
O2—C91.418 (4)C9—C101.512 (4)
O2—C81.424 (4)C9—H9A0.9900
N1—C11.335 (3)C9—H9B0.9900
N1—C21.472 (3)C10—H10A0.9900
N1—C51.473 (3)C10—H10B0.9900
N2—C61.328 (4)C11—H11A0.9800
N2—C71.468 (3)C11—H11B0.9800
N2—C101.470 (3)C11—H11C0.9800
C2—C31.515 (4)C12—H12A0.9800
C2—H2A0.9900C12—H12B0.9800
C2—H2B0.9900C12—H12C0.9800
S1—Sn—S265.935 (19)H4A—C4—H4B108.0
S1—Sn—S385.878 (19)N1—C5—C4110.3 (2)
S1—Sn—S4150.95 (2)N1—C5—H5A109.6
S1—Sn—C1199.49 (8)C4—C5—H5A109.6
S1—Sn—C12104.96 (8)N1—C5—H5B109.6
S2—Sn—S3151.798 (18)C4—C5—H5B109.6
S2—Sn—S4143.066 (18)H5A—C5—H5B108.1
S2—Sn—C1186.87 (8)N2—C6—S4122.32 (19)
S2—Sn—C1284.93 (8)N2—C6—S3119.1 (2)
S3—Sn—S465.137 (18)S4—C6—S3118.56 (15)
S3—Sn—C12102.37 (8)N2—C7—C8109.1 (2)
S3—Sn—C1199.28 (8)N2—C7—H7A109.9
S4—Sn—C1184.20 (8)C8—C7—H7A109.9
S4—Sn—C1284.15 (7)N2—C7—H7B109.9
C11—Sn—C12148.24 (11)C8—C7—H7B109.9
C1—S1—Sn92.73 (8)H7A—C7—H7B108.3
C1—S2—Sn82.29 (9)O2—C8—C7111.4 (2)
C6—S3—Sn92.55 (9)O2—C8—H8A109.3
C6—S4—Sn82.27 (9)C7—C8—H8A109.3
C4—O1—C3109.5 (2)O2—C8—H8B109.3
C9—O2—C8110.2 (2)C7—C8—H8B109.3
C1—N1—C2122.2 (2)H8A—C8—H8B108.0
C1—N1—C5123.3 (2)O2—C9—C10111.8 (2)
C2—N1—C5113.0 (2)O2—C9—H9A109.2
C6—N2—C7124.6 (2)C10—C9—H9A109.2
C6—N2—C10123.2 (2)O2—C9—H9B109.2
C7—N2—C10112.2 (2)C10—C9—H9B109.2
N1—C1—S2122.6 (2)H9A—C9—H9B107.9
N1—C1—S1118.35 (19)N2—C10—C9109.3 (2)
S2—C1—S1119.04 (14)N2—C10—H10A109.8
N1—C2—C3110.0 (2)C9—C10—H10A109.8
N1—C2—H2A109.7N2—C10—H10B109.8
C3—C2—H2A109.7C9—C10—H10B109.8
N1—C2—H2B109.7H10A—C10—H10B108.3
C3—C2—H2B109.7Sn—C11—H11A109.5
H2A—C2—H2B108.2Sn—C11—H11B109.5
O1—C3—C2111.7 (2)H11A—C11—H11B109.5
O1—C3—H3A109.3Sn—C11—H11C109.5
C2—C3—H3A109.3H11A—C11—H11C109.5
O1—C3—H3B109.3H11B—C11—H11C109.5
C2—C3—H3B109.3Sn—C12—H12A109.5
H3A—C3—H3B107.9Sn—C12—H12B109.5
O1—C4—C5111.3 (2)H12A—C12—H12B109.5
O1—C4—H4A109.4Sn—C12—H12C109.5
C5—C4—H4A109.4H12A—C12—H12C109.5
O1—C4—H4B109.4H12B—C12—H12C109.5
C5—C4—H4B109.4
C2—N1—C1—S25.5 (4)C7—N2—C6—S4179.6 (2)
C5—N1—C1—S2171.0 (2)C10—N2—C6—S43.5 (4)
C2—N1—C1—S1173.9 (2)C7—N2—C6—S30.7 (4)
C5—N1—C1—S18.4 (3)C10—N2—C6—S3176.2 (2)
Sn—S2—C1—N1179.7 (2)Sn—S4—C6—N2168.6 (2)
Sn—S2—C1—S10.98 (13)Sn—S4—C6—S311.13 (13)
Sn—S1—C1—N1179.5 (2)Sn—S3—C6—N2167.2 (2)
Sn—S1—C1—S21.11 (15)Sn—S3—C6—S412.56 (15)
C1—N1—C2—C3143.1 (3)C6—N2—C7—C8122.6 (3)
C5—N1—C2—C350.1 (3)C10—N2—C7—C854.6 (3)
C4—O1—C3—C261.3 (3)C9—O2—C8—C760.3 (3)
N1—C2—C3—O155.1 (3)N2—C7—C8—O257.4 (3)
C3—O1—C4—C561.7 (3)C8—O2—C9—C1059.5 (3)
C1—N1—C5—C4142.5 (3)C6—N2—C10—C9123.5 (3)
C2—N1—C5—C450.8 (3)C7—N2—C10—C953.7 (3)
O1—C4—C5—N156.3 (3)O2—C9—C10—N255.8 (3)
Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the (C8–C13) ring.
D—H···AD—HH···AD···AD—H···A
C10—H10A···S1i0.992.863.809 (3)161
C12—H12C···O1ii0.982.473.399 (4)158
Symmetry codes: (i) x3/2, y1/2, z3/2; (ii) x+2, y+1, z+1.
Summary of short inter-atomic contacts (Å) in (I) top
Contactdistancesymmetry operation
S4···S43.5835 (10)1 - x, 1 - y, -z
S2···H12B2.993/2 - x, 1/2 + y, 1/2 - z
S3···H5B2.941 - x, 1 - y, 1 - z
S4···H11C2.941 - x, 1 - y, - z
O2···H2A2.631/2 - x, -1/2 + y, 1/2 - z
O2···H5B2.701/2 - x, -1/2 + y, 1/2 - z
C1···H3A2.882 - x, 1 - y, 1 - z
C3···H12C2.862 - x, 1 - y, 1- z
H2A···H11C2.361/2 + x, 3/2 - y, 1/2 + z
Percentage contributions of inter-atomic contacts to the Hirshfeld surfaces for (I) top
Contactpercentage contribution
H···H56.8
S···H/H···S27.2
O···H/H···O9.9
C···/H···C4.0
N···H/H···N1.1
Sn···S/S···Sn0.5
S···S0.5
Summary of Sn—S, Sn···S distances (Å) in R2Sn(S2CNRR')2 structures featuring secondary Sn···S interactions top
RR, R'Sn—Sshort, Sn—SlongSn···SmotifRef.
MeEt, Et2.5174 (18), 2.961 (3); 2.528 (2), 2.9162 (17)3.853 (2)AMorris & Schlemper (1979)
Me(CH2CH2)Me2.5367 (14), 2.9171 (16); 2.5577 (15), 2.8953 (16)3.6978 (18)AZia-ur-Rehman et al. (2007)
Me(CH2CH2)O2.5429 (6), 2.8923 (6); 2.5649 (7), 2.9137 (6)3.5654 (7)Athis work
C(H)CH2Cy2.514 (5), 2.914 (4); 2.536 (4), 2.914 (4)3.662 (5)AHall & Tiekink (1998)
CH2PhEt, Et2.5310 (11), 2.8940 (11); 2.5396 (10), 2.9109 (11)3.8161 (12)AYin et al. (2003)
CH2PhCl-2(CH2CH2)NMe2.5401 (13), 2.8050 (13); 2.5675 (13), 2.8675 (12)3.9071 (13)AYin & Xue (2005a)
CH2PhCl-3a(CH2CH2)NEt2.520 (3), 2.840 (3); 2.556 (2), 2.893 (3)3.638 (3)AXue et al. (2005)
CH2PhCl-4(CH2CH2)NMe2.534 (2), 2.968 (3); 2.550 (2), 2.858 (3)3.765 (3)AYin & Xue (2005b)
CH2PhCN-4Et, Et2.524 (3), 2.885 (3); 2.537 (2), 2.879 (2)3.821 (3)AYin & Xue (2006)
MebEt; CH2Ph2.543 (2), 2.943 (2); 2.549 (2), 2.909 (2)3.724 (3)BBarba et al. (2012)
2.579 (2), 2.842 (2); 2.609 (2), 3.003 (2)2.978 (5)c
MedCH2Ph, 0.5(1,3-CH2C6H4CH2)2.5086 (13), 2.8791 (15); 2.5217 (14), 3.1510 (16)3.9641 (15)CSantacruz-Juárez et al. (2008)
Med,ebicyclo[2.2.1]hept-2yl, 0.5(CH2)42.5179 (12), 2.9015 (13); 2.5321 (12), 2.9600 (13)3.9453 (14)CRojas-León et al. (2012)
Mef(CH2)2i-Pr, 0.5(1,3-CH2C6H4CH2)2.5319 (18), 2.8855 (18); 2.5356 (17), 2.9663 (19)4.0480 (19)C'Santacruz-Juárez et al. (2008)
2.5306 (17), 2.9492 (19); 2.5402 (19), 2.9633 (19)3.7050 (17)
Notes: (a) piperazine mono-solvate; (b) two molecules in the asymmetric unit; (c) Sn···N secondary interaction; (d) the binuclear molecule is located about a centre of inversion; (e) CDCl3 di-solvate per binuclear entity; (f) two molecules in the asymmetric unit with each being located about a centre of inversion.
 

Footnotes

Additional correspondence author, e-mail: mmjotani@rediffmail.com.

Acknowledgements

The authors are grateful to Sunway University (INT-RRO-2017-096), the University of Malaya (award Nos. RP017B-14AFR and PG168-2016A) and the Ministry of Higher Education of Malaysia (MOHE) Fundamental Research Grant Scheme (grant No. FP033-2014B) for supporting this research.

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