(E)-2-[(E)-3-(Hy­droxy­imino)­butan-2-yl­idene]-N-methyl­hydrazinecarbothio­amide

In the title compound, C₆H₁₂N₄OS, an intra­molecular N—H...N hydrogen-bond is present giving rise to an S(5) ring motif. In the crystal, double-stranded chains propagating along [10] are formed via pairs of O—H...S and N—H...S hydrogen bonds. The chains are further stabilized by C—H...S interactions.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.001 Å
• R factor = 0.031
• wR factor = 0.081
• Data-to-parameter ratio = 26.3

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT413_ALERT_2_B Short Inter XH3 .. XHn     H4B    ..  H4B     ..       2.03 Ang.

Alert level C
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....        2.7
PLAT480_ALERT_4_C Long H...A H-Bond Reported H4C    ..  O1      ..       2.71 Ang.
PLAT480_ALERT_4_C Long H...A H-Bond Reported H6A    ..  O1      ..       2.63 Ang.
PLAT912_ALERT_4_C Missing # of FCF Reflections Above STh/L=  0.600         36

Alert level G
PLAT005_ALERT_5_G No _iucr_refine_instructions_details in CIF ....          ?
PLAT154_ALERT_1_G The su's on the Cell Angles are Equal ..........    0.00100 Deg.
PLAT720_ALERT_4_G Number of Unusual/Non-Standard Labels ..........          3

   0 ALERT level A = Most likely a serious problem - resolve or explain
   1 ALERT level B = A potentially serious problem, consider carefully
   4 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   3 ALERT level G = General information/check it is not something unexpected

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

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S1. Comment

Thiosemicarbazones and their metal complexes have attracted significant attention because of their wide-ranging biological and pharmacological activities related to specific structures as well as chemical properties (Cowley et al., 2002; Ming, 2003; Lobana et al., 2007; Lobana et al., 2004). In this paper we report the crystal structure of (E)-2-((E)-3-(hydroxyimino)butan-2-ylidene)-N-methylhydrazinecarbothioamide (Fig. 1).

In the title compound, C₆H₁₂N₄OS, butane is the longest carbon-carbon chain with the oxime group bound to C2 and the 4-methyl-3-thiosemicarbazide moiety bound to C3. The two methyl groups C1 and C4 are trans to each other. The torsion angles of the chains (O1/N1/C2/C3), (C1/C2/C3/C4) and (N2/N3/C5/N4) are 178.35 (8)°, -176.26 (10)° and -5.71 (13)°, respectively, indicating the near-planarity of the molecular backbone. All bond lengths and angles are normal (Allen et al., 1987).

Cyclic intramolecular N4—H1N4···N2, C1—H1B···N2 and C4—H4B···N1 hydrogen-bonding interactions [graph set S(5), (Bernstein et al., 1995)] are present (Table 1) with the latter two being notably weaker than the first. In the crystal molecules are connected through intermolecular O1—H1O1···S1 hydrogen bonds into infinite one-dimensional chains which propagate along [1 0 -1]. In addition, intermolecular N3—H1N3···S1, C4—H4A···S1 and C6—H6A···O1 hydrogen bonds associate these chains into sheets while the sheets are tied together via C4—H4C···O1 interactions (Fig. 2, Table 1). As a consequence of the C4—H4A···S1 and C4—H4C···O1 interactions, a rather short H4B-H4B contact is forced between adjacent molecules in the sheet.

Related literature

For standard bond lengths, see: Allen et al. (1987). For graph-set analysis of hydrogen bonds, see: Bernstein et al. (1995). For related structures, see: Choi et al. (2008). For the biological activity and pharmacological properties of thiosemicarbazones and their metal complexes, see: Cowley et al. (2002); Ming (2003); Lobana, Rekha, Pannu et al. (2007); Lobana, Rekha & Butcher (2004).

S2. Experimental

To a hot stirred solution of 2,3-butanedione monoxime (1.01 g, 10 mmole) in ethanol (20 ml) containing a few drops of glacial acetic acid was added 4-methyl-3-thiosemicarbazide (1.05 g, 10 mmole) dissolved in ethanol (20 ml). The reaction mixture was then heated under reflux for 3 h. The mixture was filtered and left to cool, the resulting white solid was collected by suction filtration and washed with cold EtOH. The white crystals were grown from ethanol soultion by slow evaporation at room temperature, yield, 78.8%, m.p., 487.5–490 K.

S3. Refinement

N and O bound H atoms were located in a difference Fourier map and were refined freely. The remaining H atoms were positioned geometrically and refined using a riding model with C—H = 0.98 and U_iso(H) = 1.5U_eq(C) for methyl groups. The highest residual electron density peak is located 0.63 Å from C2 and the deepest hole is located 0.68 Å from C4.

Computing details

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures

	Fig. 1. The molecular structure of the title compound with 50% probability displacement ellipsoids and the atom-numbering scheme.
	Fig. 2. The crystal packing of the title compound viewed down the a axis. Hydrogen bonds are shown as dashed lines.

(E)-2-[(E)-3-(Hydroxyimino)butan-2-ylidene]-N- methylhydrazinecarbothioamide

Crystal data

C6H12N4OS	Z = 2
Mr = 188.26	F(000) = 200
Triclinic, P1	Dx = 1.403 Mg m^−3
Hall symbol: -P 1	Melting point = 487.5–490 K
a = 5.5205 (1) Å	Mo Kα radiation, λ = 0.71073 Å
b = 8.6077 (2) Å	Cell parameters from 7387 reflections
c = 9.5650 (2) Å	θ = 2.4–32.7°
α = 79.750 (1)°	µ = 0.32 mm^−1
β = 89.509 (1)°	T = 100 K
γ = 85.083 (1)°	Plate, colourless
V = 445.61 (2) Å^3	0.51 × 0.25 × 0.07 mm

Data collection

Bruker APEXII CCD diffractometer	3256 independent reflections
Radiation source: fine-focus sealed tube	2920 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.020
ϕ and ω scans	θmax = 32.7°, θmin = 2.2°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −8→8
Tmin = 0.854, Tmax = 0.978	k = −13→13
12035 measured reflections	l = −14→14

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)] = 0.031	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.081	H atoms treated by a mixture of independent and constrained refinement
S = 1.08	w = 1/[σ^2(Fo^2) + (0.0347P)^2 + 0.1679P] where P = (Fo^2 + 2Fc^2)/3
3256 reflections	(Δ/σ)max = 0.001
124 parameters	Δρmax = 0.40 e Å^−3
0 restraints	Δρmin = −0.39 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	0.94334 (4)	0.16073 (3)	0.30007 (2)	0.01590 (7)
O1	−0.03857 (14)	0.29827 (9)	0.95645 (8)	0.02032 (15)
N1	0.16712 (15)	0.21630 (10)	0.90822 (9)	0.01569 (15)
N2	0.44402 (14)	0.22893 (9)	0.57941 (8)	0.01351 (14)
N3	0.64505 (15)	0.16555 (10)	0.51705 (8)	0.01452 (15)
N4	0.51169 (15)	0.32555 (10)	0.31045 (8)	0.01554 (15)
C1	0.02246 (18)	0.37515 (12)	0.67902 (10)	0.01835 (18)
H1A	−0.1458	0.3575	0.7064	0.028*
H1B	0.0464	0.3628	0.5798	0.028*
H1C	0.0556	0.4825	0.6895	0.028*
C2	0.19230 (17)	0.25693 (11)	0.77265 (10)	0.01371 (16)
C3	0.40835 (17)	0.17983 (11)	0.71298 (10)	0.01444 (16)
C4	0.5672 (2)	0.05499 (14)	0.80647 (11)	0.0258 (2)
H4A	0.6119	−0.0328	0.7560	0.039*
H4B	0.4791	0.0158	0.8932	0.039*
H4C	0.7146	0.1001	0.8314	0.039*
C5	0.68449 (17)	0.22272 (10)	0.37711 (9)	0.01296 (15)
C6	0.51377 (18)	0.39340 (12)	0.15976 (10)	0.01718 (18)
H6A	0.3703	0.4686	0.1362	0.026*
H6B	0.5111	0.3086	0.1038	0.026*
H6C	0.6612	0.4486	0.1379	0.026*
H1N3	0.754 (3)	0.0948 (18)	0.5626 (16)	0.025 (4)*
H1N4	0.387 (3)	0.3399 (18)	0.3605 (17)	0.026 (4)*
H1O1	−0.040 (3)	0.263 (2)	1.046 (2)	0.039 (4)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.01340 (11)	0.02020 (11)	0.01157 (10)	0.00444 (8)	0.00346 (7)	0.00102 (7)
O1	0.0191 (3)	0.0277 (4)	0.0116 (3)	0.0092 (3)	0.0044 (3)	−0.0022 (3)
N1	0.0146 (4)	0.0190 (3)	0.0124 (3)	0.0039 (3)	0.0031 (3)	−0.0025 (3)
N2	0.0128 (3)	0.0160 (3)	0.0112 (3)	0.0009 (3)	0.0029 (3)	−0.0020 (3)
N3	0.0135 (3)	0.0179 (3)	0.0102 (3)	0.0041 (3)	0.0024 (3)	0.0002 (3)
N4	0.0135 (4)	0.0203 (4)	0.0103 (3)	0.0044 (3)	0.0026 (3)	0.0012 (3)
C1	0.0175 (4)	0.0223 (4)	0.0126 (4)	0.0057 (3)	0.0007 (3)	0.0005 (3)
C2	0.0134 (4)	0.0154 (4)	0.0113 (4)	0.0017 (3)	0.0009 (3)	−0.0013 (3)
C3	0.0151 (4)	0.0161 (4)	0.0107 (4)	0.0028 (3)	0.0019 (3)	−0.0006 (3)
C4	0.0265 (5)	0.0314 (5)	0.0129 (4)	0.0159 (4)	0.0054 (4)	0.0048 (4)
C5	0.0129 (4)	0.0145 (4)	0.0108 (4)	0.0004 (3)	0.0014 (3)	−0.0014 (3)
C6	0.0180 (4)	0.0202 (4)	0.0106 (4)	0.0046 (3)	0.0013 (3)	0.0017 (3)

Geometric parameters (Å, º)

S1—C5	1.6914 (9)	C1—H1A	0.9800
O1—N1	1.4034 (10)	C1—H1B	0.9800
O1—H1O1	0.858 (19)	C1—H1C	0.9800
N1—C2	1.2911 (12)	C2—C3	1.4752 (13)
N2—C3	1.2912 (12)	C3—C4	1.4944 (13)
N2—N3	1.3733 (11)	C4—H4A	0.9800
N3—C5	1.3639 (12)	C4—H4B	0.9800
N3—H1N3	0.876 (15)	C4—H4C	0.9800
N4—C5	1.3285 (12)	C6—H6A	0.9800
N4—C6	1.4560 (12)	C6—H6B	0.9800
N4—H1N4	0.847 (16)	C6—H6C	0.9800
C1—C2	1.4977 (13)
N1—O1—H1O1	104.1 (12)	N2—C3—C2	115.15 (8)
C2—N1—O1	111.22 (8)	N2—C3—C4	125.00 (9)
C3—N2—N3	118.54 (8)	C2—C3—C4	119.84 (8)
C5—N3—N2	117.75 (8)	C3—C4—H4A	109.5
C5—N3—H1N3	118.0 (10)	C3—C4—H4B	109.5
N2—N3—H1N3	124.1 (10)	H4A—C4—H4B	109.5
C5—N4—C6	124.53 (8)	C3—C4—H4C	109.5
C5—N4—H1N4	114.1 (11)	H4A—C4—H4C	109.5
C6—N4—H1N4	120.9 (11)	H4B—C4—H4C	109.5
C2—C1—H1A	109.5	N4—C5—N3	116.23 (8)
C2—C1—H1B	109.5	N4—C5—S1	124.44 (7)
H1A—C1—H1B	109.5	N3—C5—S1	119.33 (7)
C2—C1—H1C	109.5	N4—C6—H6A	109.5
H1A—C1—H1C	109.5	N4—C6—H6B	109.5
H1B—C1—H1C	109.5	H6A—C6—H6B	109.5
N1—C2—C3	115.02 (8)	N4—C6—H6C	109.5
N1—C2—C1	124.30 (8)	H6A—C6—H6C	109.5
C3—C2—C1	120.68 (8)	H6B—C6—H6C	109.5
C3—N2—N3—C5	−177.76 (8)	N1—C2—C3—C4	4.82 (14)
O1—N1—C2—C3	178.35 (8)	C1—C2—C3—C4	−176.26 (10)
O1—N1—C2—C1	−0.52 (13)	C6—N4—C5—N3	−176.61 (9)
N3—N2—C3—C2	178.38 (8)	C6—N4—C5—S1	3.43 (14)
N3—N2—C3—C4	−1.47 (15)	N2—N3—C5—N4	−5.71 (13)
N1—C2—C3—N2	−175.03 (9)	N2—N3—C5—S1	174.25 (6)
C1—C2—C3—N2	3.88 (13)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N3—H1N3···S1^i	0.877 (16)	2.781 (16)	3.6519 (9)	172.0 (14)
N4—H1N4···N2	0.848 (16)	2.155 (16)	2.5932 (11)	111.9 (13)
O1—H1O1···S1^ii	0.857 (19)	2.437 (19)	3.2930 (8)	178.3 (17)
C1—H1B···N2	0.98	2.39	2.7919 (13)	104
C4—H4A···S1^i	0.98	2.69	3.3991 (12)	129
C4—H4B···N1	0.98	2.35	2.7698 (14)	105
C4—H4C···O1^iii	0.98	2.71	3.6173 (16)	154
C6—H6A···O1^iv	0.98	2.63	3.6011 (12)	170

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