research communications
N-[(methylsulfanyl)carbonyl]urea
ofaLaboratoire de Chimie Minérale et Analytique, Département de Chimie, Faculté des Sciences et Techniques, Université Cheikh Anta Diop, Dakar, Senegal, and bDepartment of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46557-5670, USA
*Correspondence e-mail: mouhamadoubdiop@gmail.com
The almost planar (r.m.s. deviation = 0.055 Å) title compound, (MeS)C(O)NHC(O)NH2, was formed during an attempted crystallization of dimethyl cyanocarbonimidodithioate with CrO2Cl2; an unexpected redox reaction converted the cyanocarbonimido moiety to a urea group and removed one methylthiol group. In the crystal, hydrogen-bonding interactions from the amide and amido N—H groups to carbonyl O atoms of neighbouring molecules result in [010] ribbon-like chains.
Keywords: crystal structure; hydrogen bonds; one-dimensional structure.
CCDC reference: 1452062
1. Chemical context
We have recently reported that dimethyl cyanocarbonimidodithioate (MeS)2C=N—C≡N is an N-donor ligand, coordinating to metal centres (Diop et al., 2016). In an attempt to broaden data on the coordination ability of this ligand, we have initiated here a study of the interactions between dimethyl cyanocarbonimidodithioate and CrO2Cl2 which yielded the title compound whose X-ray study is reported in this work. Surprisingly, the dimethyl cyanocarbonimidodithioate has undergone redox reactivity at both the cyanide (N1/C1) and the imido (N2/C2) functionalities. The carbon atoms associated with these groups have been oxidized to an amide and both nitrogen atoms now sport hydrogen atoms. One methylthiol group has been removed during this reaction. Presumably adventitious water is the source of the oxygen and hydrogen. This was unexpected reactivity. It is not known if or how the CrO2Cl2 plays a role in this reaction.
2. Structural commentary
The starting dimethyl cyanocarbonimidodithioate (MeS)2C=N—C≡N has undergone oxidation yielding the title compound (MeS)C(O)NHC(O)NH2 (Fig. 1). Bond distances and angles within the molecule are in the expected range (Sow et al., 2014; Jalový et al., 2011). Although the C1—N1 [1.3159 (19) Å] bond appears shorter than the C2—N2 [1.3623 (18) Å] and C1—N2 [1.3977 (18) Å] bonds, all three are within expected ranges for urea N—C bond distances (MOGUL analysis; Bruno et al., 2004) because of the different substituents on the carbon atoms. The C2—S1—C3 bond angle is 99.22 (7)°. The torsion angles are close to zero or 180°, which is consistent with a nearly planar molecule (r.m.s. deviation for the non-hydrogen atoms = 0.055 Å). An intramolecular N1—H1NB⋯O2 hydrogen bond generates an S(6) ring (see Table 1).
3. Supramolecular features
In the crystal, the compound forms a hydrogen-bonded dimer with a molecule related through the inversion center at (½, ½, 0) [N1⋯O1ii; symmetry code: (ii) −x + 1, −y + 1, −z). This `head-to-head' arrangement forces the non-interacting thiomethyl groups to be on the exterior of the chain. These hydrogen-bonded dimers propagate into a one-dimensional chain parallel to the b axis (Fig. 2) through hydrogen bonds from N1⋯O1i and N2⋯O2iii [symmetry codes: (i) x, y − 1, z; (iii) x, y + 1, z]. The ribbons are oriented approximately parallel to the [30] plane. The compactness and the stability of the structure are consolidated through and weak C—H⋯O and C—H⋯S hydrogen bonds(Table 1).
4. Database survey
To the best of our knowledge there are no reported structures that contain the N-[(methylsulfanyl)carbonyl]urea group (CSD Version 5.37 plus one update; Groom &Allen, 2014).
5. Synthesis and crystallization
All chemicals are purchased from Aldrich Company (Germany) and used as received. Dimethyl cyanocarbonimidodithioate was mixed in acetonitrile with CrO2Cl2 in a 1:1 ratio: a green solution was obtained. Two colourless crystals – one of which being this studied compound – suitable for a single-crystal X-ray diffraction study were obtained after a slow solvent evaporation at room temperature (303 K).
6. Refinement
Crystal data, data collection and structure . Urea hydrogen atoms were located from a difference Fourier map and refined freely. Methyl hydrogen atoms were included in geometrically calculated positions and allowed to rotate to minimize their contribution to electron density with C—H = 0.98 Å and Uiso(H) = 1.5Ueq(C3).
details are summarized in Table 2
|
Supporting information
CCDC reference: 1452062
10.1107/S2056989016002322/hb7563sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S2056989016002322/hb7563Isup2.hkl
Supporting information file. DOI: 10.1107/S2056989016002322/hb7563Isup3.cml
We have recently reported that dimethyl cyanocarbonimidodithioate (MeS)2C═ N—C≡N is an N-donor ligand, coordinating to metal centres (Diop et al., 2016). In an attempt to broaden data on this ligand coordination ability, we have initiated here a study of the interactions between dimethyl cyanocarbonimidodithioate and CrO2Cl2 which yielded the title compound whose X-ray study is reported in this work. Surprisingly, the dimethyl cyanocarbonimidodithioate has undergone redox reactivity at both the cyanide (N1/C1) and the imido (N2/C2) functionalities. The carbon atoms associated with these groups have been oxidized to an amide and both nitrogen atoms now sport hydrogen atoms. One methylthiol group has been removed during this reaction. Presumably adventitious water is the source of the oxygen and hydrogen. This was unexpected reactivity. It is not known if or how the CrO2Cl2 plays a role in this reaction.
The starting dimethyl cyanocarbonimidodithioate (MeS)2C═N—C≡N has undergone oxidation yielding the title compound (MeS)C(O)NHC(O)NH2 (Fig. 1). Bond distances and angles within the molecule are in the expected range (Sow et al., 2014; Jalový et al., 2011). Although the C1—N1 [1.3159 (19) Å] bond appears shorter than the C2—N2 [1.3623 (18) Å] and C1—N2 [1.3977 (18) Å] bonds, all three are within expected ranges for urea N—C bond distances (MOGUL analysis; Bruno et al., 2004) because of the different substituents on the carbon atoms. The C2—S1—C3 bond angle is 99.22 (7)°. The torsion angles are close to zero or 180°, which is consistent with a nearly planar molecule (r.m.s. deviation for the non-hydrogen atoms = 0.055 Å). An intramolecular N1—H1NB···O2 hydrogen bond generates an S(6) ring (see Table 1).
In the crystal, the compound forms a hydrogen-bonded dimer with a molecule related through the inversion center at (1/2, 1/2, 0) [N1···O1ii; symmetry code: (ii) -x + 1, -y + 1, -z). This `head-to-head' arrangement forces the non-interacting thiomethyl groups to be on the exterior of the chain. These hydrogen-bonded dimers propagate into a one-dimensional chain parallel to the b axis through hydrogen bonds from N1···O1i and N2···O2iii [symmetry codes: (i) x, y - 1, z ; (iii) x, y + 1, z]. The ribbons are oriented approximately parallel to the [301] plane. The compactness and the stability of the structure are consolidated through and weak C—H···O and C—H···S hydrogen bonds(Table 1).
To the best of our knowledge there are no reported structures that contain the N-(thiomethylmethanoyl) urea group (CSD Version 5.37 + 1 update; Groom &Allen, 2014).
All chemicals are purchased from Aldrich Company (Germany) and used as received. Dimethyl cyanocarbonimidodithioate was mixed in acetonitrile with CrO2Cl2 in a 1:1 ratio: a green solution was obtained. Two colourless crystals – one of which being this studied compound – suitable for a single-crystal X-ray diffraction study were obtained after a slow solvent evaporation at room temperature (303 K).
Crystal data, data collection and structure
details are summarized in Table 2. Urea hydrogen atoms were located from a difference Fourier map and refined freely. Methyl hydrogen atoms were included in geometrically calculated positions and allowed to rotate to minimize their contribution to electron density with C—H = 0.98 Å and Uiso(H) = 1.5Ueq(C3) .We have recently reported that dimethyl cyanocarbonimidodithioate (MeS)2C═ N—C≡N is an N-donor ligand, coordinating to metal centres (Diop et al., 2016). In an attempt to broaden data on this ligand coordination ability, we have initiated here a study of the interactions between dimethyl cyanocarbonimidodithioate and CrO2Cl2 which yielded the title compound whose X-ray study is reported in this work. Surprisingly, the dimethyl cyanocarbonimidodithioate has undergone redox reactivity at both the cyanide (N1/C1) and the imido (N2/C2) functionalities. The carbon atoms associated with these groups have been oxidized to an amide and both nitrogen atoms now sport hydrogen atoms. One methylthiol group has been removed during this reaction. Presumably adventitious water is the source of the oxygen and hydrogen. This was unexpected reactivity. It is not known if or how the CrO2Cl2 plays a role in this reaction.
The starting dimethyl cyanocarbonimidodithioate (MeS)2C═N—C≡N has undergone oxidation yielding the title compound (MeS)C(O)NHC(O)NH2 (Fig. 1). Bond distances and angles within the molecule are in the expected range (Sow et al., 2014; Jalový et al., 2011). Although the C1—N1 [1.3159 (19) Å] bond appears shorter than the C2—N2 [1.3623 (18) Å] and C1—N2 [1.3977 (18) Å] bonds, all three are within expected ranges for urea N—C bond distances (MOGUL analysis; Bruno et al., 2004) because of the different substituents on the carbon atoms. The C2—S1—C3 bond angle is 99.22 (7)°. The torsion angles are close to zero or 180°, which is consistent with a nearly planar molecule (r.m.s. deviation for the non-hydrogen atoms = 0.055 Å). An intramolecular N1—H1NB···O2 hydrogen bond generates an S(6) ring (see Table 1).
In the crystal, the compound forms a hydrogen-bonded dimer with a molecule related through the inversion center at (1/2, 1/2, 0) [N1···O1ii; symmetry code: (ii) -x + 1, -y + 1, -z). This `head-to-head' arrangement forces the non-interacting thiomethyl groups to be on the exterior of the chain. These hydrogen-bonded dimers propagate into a one-dimensional chain parallel to the b axis through hydrogen bonds from N1···O1i and N2···O2iii [symmetry codes: (i) x, y - 1, z ; (iii) x, y + 1, z]. The ribbons are oriented approximately parallel to the [301] plane. The compactness and the stability of the structure are consolidated through and weak C—H···O and C—H···S hydrogen bonds(Table 1).
To the best of our knowledge there are no reported structures that contain the N-(thiomethylmethanoyl) urea group (CSD Version 5.37 + 1 update; Groom &Allen, 2014).
All chemicals are purchased from Aldrich Company (Germany) and used as received. Dimethyl cyanocarbonimidodithioate was mixed in acetonitrile with CrO2Cl2 in a 1:1 ratio: a green solution was obtained. Two colourless crystals – one of which being this studied compound – suitable for a single-crystal X-ray diffraction study were obtained after a slow solvent evaporation at room temperature (303 K).
detailsCrystal data, data collection and structure
details are summarized in Table 2. Urea hydrogen atoms were located from a difference Fourier map and refined freely. Methyl hydrogen atoms were included in geometrically calculated positions and allowed to rotate to minimize their contribution to electron density with C—H = 0.98 Å and Uiso(H) = 1.5Ueq(C3) .Data collection: APEX3 (Bruker, 2015); cell
SAINT (Bruker, 2015); data reduction: SAINT (Bruker, 2015); program(s) used to solve structure: SHELXT2014 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: publCIF (Westrip, 2010).Fig. 1. The molecular structure of the title compound. Displacement ellipsoids are depicted at the 50% probability level and H atoms as spheres of an arbitrary radius. | |
Fig. 2. Packing diagram of the title compound showing one-dimensional hydrogen-bonded chains (dashed lines) viewed along the a axis. |
C3H6N2O2S | F(000) = 280 |
Mr = 134.16 | Dx = 1.651 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
a = 9.9388 (13) Å | Cell parameters from 3996 reflections |
b = 5.0999 (6) Å | θ = 2.7–28.3° |
c = 10.6755 (14) Å | µ = 0.50 mm−1 |
β = 94.136 (4)° | T = 120 K |
V = 539.70 (12) Å3 | Tablet, colorless |
Z = 4 | 0.24 × 0.19 × 0.14 mm |
Bruker Kappa X8-APEXII diffractometer | 1344 independent reflections |
Radiation source: fine-focus sealed tube | 1220 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.024 |
Detector resolution: 8.33 pixels mm-1 | θmax = 28.4°, θmin = 2.7° |
combination of ω and φ–scans | h = −13→13 |
Absorption correction: multi-scan (SADABS; Krause et al., 2015) | k = −6→6 |
Tmin = 0.679, Tmax = 0.734 | l = −8→14 |
8437 measured reflections |
Refinement on F2 | Primary atom site location: real-space vector search |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.031 | Hydrogen site location: mixed |
wR(F2) = 0.084 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.09 | w = 1/[σ2(Fo2) + (0.0502P)2 + 0.2127P] where P = (Fo2 + 2Fc2)/3 |
1344 reflections | (Δ/σ)max = 0.001 |
86 parameters | Δρmax = 0.38 e Å−3 |
0 restraints | Δρmin = −0.23 e Å−3 |
C3H6N2O2S | V = 539.70 (12) Å3 |
Mr = 134.16 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 9.9388 (13) Å | µ = 0.50 mm−1 |
b = 5.0999 (6) Å | T = 120 K |
c = 10.6755 (14) Å | 0.24 × 0.19 × 0.14 mm |
β = 94.136 (4)° |
Bruker Kappa X8-APEXII diffractometer | 1344 independent reflections |
Absorption correction: multi-scan (SADABS; Krause et al., 2015) | 1220 reflections with I > 2σ(I) |
Tmin = 0.679, Tmax = 0.734 | Rint = 0.024 |
8437 measured reflections |
R[F2 > 2σ(F2)] = 0.031 | 0 restraints |
wR(F2) = 0.084 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.09 | Δρmax = 0.38 e Å−3 |
1344 reflections | Δρmin = −0.23 e Å−3 |
86 parameters |
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 | ||
S1 | 0.69406 (4) | 0.42571 (7) | 0.54507 (3) | 0.01914 (14) | |
O1 | 0.54686 (11) | 0.7074 (2) | 0.13127 (9) | 0.0204 (2) | |
O2 | 0.62689 (10) | 0.08127 (18) | 0.36859 (10) | 0.0183 (2) | |
N1 | 0.55218 (13) | 0.2665 (2) | 0.13289 (12) | 0.0186 (3) | |
H1NB | 0.5637 (18) | 0.144 (5) | 0.1744 (19) | 0.025 (5)* | |
H1NA | 0.521 (2) | 0.276 (5) | 0.055 (2) | 0.036 (5)* | |
N2 | 0.61955 (13) | 0.5113 (2) | 0.31095 (12) | 0.0162 (3) | |
H2NA | 0.6285 (16) | 0.660 (4) | 0.3351 (16) | 0.013 (4)* | |
C1 | 0.57029 (14) | 0.4988 (3) | 0.18511 (13) | 0.0157 (3) | |
C2 | 0.64159 (13) | 0.3108 (3) | 0.39424 (12) | 0.0154 (3) | |
C3 | 0.70883 (16) | 0.1190 (3) | 0.62609 (14) | 0.0229 (3) | |
H3A | 0.6205 | 0.0327 | 0.6228 | 0.034* | |
H3B | 0.7408 | 0.1494 | 0.7139 | 0.034* | |
H3C | 0.7732 | 0.0067 | 0.5860 | 0.034* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S1 | 0.0303 (2) | 0.0137 (2) | 0.0128 (2) | −0.00005 (12) | −0.00299 (14) | −0.00060 (12) |
O1 | 0.0322 (6) | 0.0120 (5) | 0.0162 (5) | 0.0004 (4) | −0.0045 (4) | 0.0002 (4) |
O2 | 0.0258 (5) | 0.0117 (5) | 0.0169 (5) | −0.0011 (4) | −0.0023 (4) | −0.0009 (4) |
N1 | 0.0296 (7) | 0.0110 (6) | 0.0143 (6) | 0.0009 (5) | −0.0044 (5) | 0.0012 (5) |
N2 | 0.0234 (6) | 0.0112 (6) | 0.0137 (6) | −0.0014 (4) | −0.0009 (4) | −0.0014 (4) |
C1 | 0.0182 (6) | 0.0146 (6) | 0.0141 (6) | 0.0002 (5) | 0.0003 (5) | 0.0000 (5) |
C2 | 0.0165 (6) | 0.0153 (6) | 0.0143 (6) | −0.0001 (5) | 0.0000 (5) | −0.0006 (5) |
C3 | 0.0336 (8) | 0.0172 (7) | 0.0170 (7) | −0.0016 (6) | −0.0037 (6) | 0.0041 (5) |
S1—C2 | 1.7569 (14) | C2—N2 | 1.3623 (18) |
S1—C3 | 1.7885 (15) | C1—N2 | 1.3977 (18) |
C1—O1 | 1.2239 (18) | N2—H2NA | 0.805 (19) |
C2—O2 | 1.2088 (17) | C3—H3A | 0.9800 |
C1—N1 | 1.3159 (19) | C3—H3B | 0.9800 |
N1—H1NB | 0.77 (2) | C3—H3C | 0.9800 |
N1—H1NA | 0.87 (2) | ||
C2—S1—C3 | 99.22 (7) | O2—C2—N2 | 124.61 (13) |
C1—N1—H1NB | 118.6 (16) | O2—C2—S1 | 123.61 (11) |
C1—N1—H1NA | 112.5 (16) | N2—C2—S1 | 111.78 (10) |
H1NB—N1—H1NA | 129 (2) | S1—C3—H3A | 109.5 |
C2—N2—C1 | 128.44 (12) | S1—C3—H3B | 109.5 |
C2—N2—H2NA | 119.3 (12) | H3A—C3—H3B | 109.5 |
C1—N2—H2NA | 112.0 (12) | S1—C3—H3C | 109.5 |
O1—C1—N1 | 124.62 (13) | H3A—C3—H3C | 109.5 |
O1—C1—N2 | 116.95 (13) | H3B—C3—H3C | 109.5 |
N1—C1—N2 | 118.43 (13) | ||
C2—N2—C1—O1 | 173.40 (14) | C1—N2—C2—S1 | −176.11 (11) |
C2—N2—C1—N1 | −6.5 (2) | C3—S1—C2—O2 | −1.02 (14) |
C1—N2—C2—O2 | 3.7 (2) | C3—S1—C2—N2 | 178.83 (11) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1NB···O1i | 0.77 (2) | 2.27 (2) | 2.8518 (16) | 132.3 (19) |
N1—H1NB···O2 | 0.77 (2) | 2.15 (2) | 2.7397 (17) | 134 (2) |
N1—H1NA···O1ii | 0.87 (2) | 2.05 (2) | 2.9221 (16) | 178 (2) |
N2—H2NA···O2iii | 0.805 (19) | 2.18 (2) | 2.9709 (15) | 168.9 (16) |
C3—H3A···O2iv | 0.98 | 2.54 | 3.494 (2) | 166 |
C3—H3B···S1v | 0.98 | 2.85 | 3.7064 (15) | 147 |
Symmetry codes: (i) x, y−1, z; (ii) −x+1, −y+1, −z; (iii) x, y+1, z; (iv) −x+1, −y, −z+1; (v) −x+3/2, y−1/2, −z+3/2. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1NB···O1i | 0.77 (2) | 2.27 (2) | 2.8518 (16) | 132.3 (19) |
N1—H1NB···O2 | 0.77 (2) | 2.15 (2) | 2.7397 (17) | 134 (2) |
N1—H1NA···O1ii | 0.87 (2) | 2.05 (2) | 2.9221 (16) | 178 (2) |
N2—H2NA···O2iii | 0.805 (19) | 2.18 (2) | 2.9709 (15) | 168.9 (16) |
C3—H3A···O2iv | 0.98 | 2.54 | 3.494 (2) | 166 |
C3—H3B···S1v | 0.98 | 2.85 | 3.7064 (15) | 147 |
Symmetry codes: (i) x, y−1, z; (ii) −x+1, −y+1, −z; (iii) x, y+1, z; (iv) −x+1, −y, −z+1; (v) −x+3/2, y−1/2, −z+3/2. |
Experimental details
Crystal data | |
Chemical formula | C3H6N2O2S |
Mr | 134.16 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 120 |
a, b, c (Å) | 9.9388 (13), 5.0999 (6), 10.6755 (14) |
β (°) | 94.136 (4) |
V (Å3) | 539.70 (12) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.50 |
Crystal size (mm) | 0.24 × 0.19 × 0.14 |
Data collection | |
Diffractometer | Bruker Kappa X8-APEXII |
Absorption correction | Multi-scan (SADABS; Krause et al., 2015) |
Tmin, Tmax | 0.679, 0.734 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 8437, 1344, 1220 |
Rint | 0.024 |
(sin θ/λ)max (Å−1) | 0.669 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.031, 0.084, 1.09 |
No. of reflections | 1344 |
No. of parameters | 86 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.38, −0.23 |
Computer programs: APEX3 (Bruker, 2015), SAINT (Bruker, 2015), SHELXT2014 (Sheldrick, 2015a), SHELXL2014 (Sheldrick, 2015b), XP in SHELXTL (Sheldrick, 2008), publCIF (Westrip, 2010).
Acknowledgements
The authors acknowledge the Cheikh Anta Diop University of Dakar (Sénégal) and the University of Notre Dame (USA) for financial support. The Dakar group thanks Professor Tebello Nyokong, Rhodes University, South Africa, for equipment support.
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