2-Methyl-3-thio­semicarbazide

The title compound, C₂H₇N₃S, exhibits an anti arrangement between the thione S atom and the hydrazine N atom. The thio­semicarbazide mol­ecules are inter­connected into a three-dimensional hydrogen-bonded network.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](N-C) = 0.003 Å
• R factor = 0.037
• wR factor = 0.088
• Data-to-parameter ratio = 13.4

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT420_ALERT_2_C D-H Without Acceptor       N1     -   H1A    ...          ?
PLAT480_ALERT_4_C Long H...A H-Bond Reported H1A    ..  S1      ..       2.90 Ang.

Alert level G
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          6

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

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

As part of a study on the supramolecular structure of thiosemicarbazones and its metal complexes we found necessary for comparisons to know the crystal structure of the 2-methyl-3-thiosemicarbazide, (I).

The molecule (I) presents an anti arrangement between the S atom and the hydrazinic N atom with respect to the N2–C1 bond, as shown in Fig. 1. The molecule is nearly planar with the C2 [0.057 (2) Å] and N3 [0.053 (2) Å] showing the greater deviation from the mean plane of the molecule. The anti conformation is reinforced by an intramolecular N3–H3A ··· N1.

The two H atoms on N3 form N–H···S hydrogen bonds generating tapes (Fig. 2). These tapes are interconected into a 3-dimmensional H-bonded structure through N1–HA···S and N1–HB···S H-bonds (Fig. 3).

Related literature

For general background, see: Allen et al. (1997); Casas et al. (2000).

For related structures, see: Rapheal et al. (2005); West et al., (2001); Castineiras et al. (2000); Lynch & McClenaghan (2000); Valente et al. (1998); Chattopadhyay et al. (1987, 1991); Andreetti et al. (1970).

S2. Experimental

Crystals of I were obtained directly from the botle of the commercial product (Aldrich).

S3. Refinement

C-bound H atoms were placed in geometrically idealized positions and refined using the riding model, with C–H = 0.96 Å. H atoms on N atoms were located in a difference map and their positional parameters were refined. The U_iso(H) values were set at 1.5 E_eq for methyl H atoms and 1.2 U_eq(N) for N–H atoms.

Computing details

Data collection: SMART (Bruker, 1999); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT (Bruker, 1999); program(s) used to solve structure: SHELXTL (Sheldrick, 2000); program(s) used to refine structure: SHELXTL (Sheldrick, 2000); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2007).

Figures

	Fig. 1. Molecular structure of I, showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level and H atoms are shown as small spheres of arbitrary radius.
	Fig. 2. Hydrogen bonded tapes observed in the crystal structure of (I). Hydrogen bonds are shown as dashed lines.
	Fig. 3. The crystal packing of (I). Hydrogen bonds are shown as dashed lines.

2-Methyl-3-thiosemicarbazide

Crystal data

C2H7N3S	F(000) = 224
Mr = 105.17	Dx = 1.404 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 2596 reflections
a = 8.606 (2) Å	θ = 2.9–25.4°
b = 5.940 (1) Å	µ = 0.50 mm^−1
c = 9.843 (2) Å	T = 298 K
β = 98.641 (3)°	Prism, clear colourless
V = 497.46 (17) Å^3	0.45 × 0.33 × 0.19 mm
Z = 4

Data collection

Bruker SMART APEX CCD diffractometer	912 independent reflections
Radiation source: fine-focus sealed tube	805 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.080
Detector resolution: 0.661 pixels mm^-1	θmax = 25.4°, θmin = 2.9°
ω–scans	h = −10→10
Absorption correction: analytical (XPREP in SHELXTL; Sheldrick, 2000)	k = −7→7
Tmin = 0.814, Tmax = 0.915	l = −11→11
3668 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)] = 0.037	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.088	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	w = 1/[σ^2(Fo^2) + (0.0392P)^2 + 0.0728P] where P = (Fo^2 + 2Fc^2)/3
912 reflections	(Δ/σ)max < 0.001
68 parameters	Δρmax = 0.25 e Å^−3
6 restraints	Δρmin = −0.20 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
S1	0.94085 (5)	0.40767 (8)	0.26511 (6)	0.0435 (2)
N1	1.2493 (2)	0.8483 (3)	0.4444 (2)	0.0470 (5)
H1A	1.279 (3)	0.839 (4)	0.5340 (19)	0.070*
H1B	1.335 (3)	0.868 (4)	0.409 (3)	0.070*
N2	1.18369 (17)	0.6403 (2)	0.39541 (17)	0.0360 (4)
N3	0.9600 (2)	0.8401 (3)	0.3293 (2)	0.0454 (5)
H3A	1.014 (3)	0.958 (4)	0.363 (3)	0.068*
H3B	0.863 (2)	0.845 (4)	0.291 (3)	0.068*
C1	1.0337 (2)	0.6427 (3)	0.33555 (19)	0.0332 (4)
C2	1.2784 (2)	0.4402 (3)	0.4250 (2)	0.0452 (5)
H2A	1.2199	0.3108	0.3880	0.068*
H2B	1.3059	0.4235	0.5227	0.068*
H2C	1.3724	0.4533	0.3840	0.068*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.0331 (3)	0.0333 (3)	0.0622 (4)	−0.00350 (19)	0.0011 (2)	−0.0053 (2)
N1	0.0418 (10)	0.0371 (10)	0.0599 (12)	−0.0072 (7)	0.0007 (9)	−0.0092 (8)
N2	0.0307 (8)	0.0276 (8)	0.0486 (10)	−0.0008 (6)	0.0029 (7)	−0.0021 (7)
N3	0.0337 (9)	0.0314 (9)	0.0694 (13)	0.0038 (7)	0.0021 (8)	−0.0028 (8)
C1	0.0306 (10)	0.0299 (10)	0.0405 (10)	0.0002 (7)	0.0102 (8)	0.0023 (7)
C2	0.0354 (10)	0.0385 (12)	0.0596 (14)	0.0067 (8)	−0.0003 (9)	0.0009 (9)

Geometric parameters (Å, º)

S1—C1	1.704 (3)	N3—C1	1.330 (2)
N1—N2	1.413 (2)	N3—H3A	0.87 (2)
N1—H1A	0.88 (2)	N3—H3B	0.86 (2)
N1—H1B	0.87 (2)	C2—H2A	0.9600
N2—C1	1.336 (2)	C2—H2B	0.9600
N2—C2	1.446 (2)	C2—H2C	0.9600
N2—N1—H1A	109 (2)	N3—C1—N2	116.9 (2)
N2—N1—H1B	107 (2)	N3—C1—S1	120.8 (2)
H1A—N1—H1B	106 (3)	N2—C1—S1	122.2 (1)
C1—N2—N1	116.8 (1)	N2—C2—H2A	109.5
C1—N2—C2	125.2 (2)	N2—C2—H2B	109.5
N1—N2—C2	117.8 (2)	H2A—C2—H2B	109.5
C1—N3—H3A	117 (2)	N2—C2—H2C	109.5
C1—N3—H3B	118 (2)	H2A—C2—H2C	109.5
H3A—N3—H3B	124 (2)	H2B—C2—H2C	109.5

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···S1^i	0.88 (2)	2.90 (2)	3.636 (2)	142 (2)
N1—H1B···S1^ii	0.87 (2)	2.78 (2)	3.625 (2)	166 (3)
N3—H3A···N1	0.87 (2)	2.17 (3)	2.576 (3)	108 (2)
N3—H3A···S1^iii	0.87 (2)	2.88 (2)	3.430 (2)	123 (2)
N3—H3B···S1^iv	0.86 (2)	2.62 (2)	3.460 (2)	165 (2)

Symmetry codes: (i) x+1/2, −y+3/2, z+1/2; (ii) −x+5/2, y+1/2, −z+1/2; (iii) x, y+1, z; (iv) −x+3/2, y+1/2, −z+1/2.