2-(Nitro­methyl­ene)-1,3-dithietane

In the crystal structure of the title compound, C₃H₃NO₂S₂, the four-membered C₂S₂ ring is planar, as is the whole mol­ecule. The short intramolecular S...O distance of 2.687 (2) Å shows the five-atom system to be conjugated. The mol­ecules pack as a two-dimensional network in the (010) plane through short intermolecular S...O [2.900 (2) and 3.077 (2) Å] interactions.

Computing details

Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 1997); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL, PARST (Nardelli, 1995) and PLATON (Spek, 1990).

2-(Nitromethylene)-1,3-dithietane

Crystal data

C3H3NO2S2	F(000) = 304
Mr = 149.18	Dx = 1.786 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
a = 3.9198 (1) Å	Cell parameters from 2751 reflections
b = 18.3222 (5) Å	θ = 2.2–28.3°
c = 7.9352 (2) Å	µ = 0.85 mm^−1
β = 103.221 (2)°	T = 293 K
V = 554.80 (3) Å^3	Slab, light green
Z = 4	0.32 × 0.20 × 0.12 mm

Data collection

Siemens SMART CCD area-detector diffractometer	1359 independent reflections
Radiation source: fine-focus sealed tube	1108 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.048
Detector resolution: 8.33 pixels mm^-1	θmax = 28.3°, θmin = 2.2°
ω scans	h = −5→3
Absorption correction: empirical (using intensity measurements) (SADABS; Sheldrick, 1996)	k = −23→24
Tmin = 0.772, Tmax = 0.904	l = −10→10
3834 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)] = 0.038	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.099	H-atom parameters constrained
S = 0.99	w = 1/[σ^2(Fo^2) + (0.0538P)^2] where P = (Fo^2 + 2Fc^2)/3
1359 reflections	(Δ/σ)max < 0.001
73 parameters	Δρmax = 0.37 e Å^−3
0 restraints	Δρmin = −0.55 e Å^−3

Special details

Experimental. The data collection covered over a hemisphere of reciprocal space by a combination of three sets of exposures; each set had a different φ angle (0, 88 and 180°) for the crystal and each exposure of 10 s covered 0.3° in ω. The crystal-to-detector distance was 4 cm and the detector swing angle was -35°. Coverage of the unique set is over 99% complete. Crystal decay was monitored by repeating fifty initial frames at the end of data collection and analysing the duplicate reflections, and was found to be negligible.

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	0.20001 (15)	0.08072 (3)	0.44923 (6)	0.03222 (18)
S2	−0.03068 (15)	0.19503 (3)	0.59751 (7)	0.03488 (19)
O1	0.0405 (5)	0.17114 (10)	0.9379 (2)	0.0523 (5)
O2	0.2745 (7)	0.07835 (11)	1.0940 (2)	0.0703 (7)
N1	0.1821 (5)	0.11000 (12)	0.9522 (2)	0.0406 (5)
C1	0.0150 (7)	0.16982 (12)	0.3818 (3)	0.0368 (5)
H1A	−0.2078	0.1670	0.2982	0.044*
H1B	0.1756	0.2013	0.3391	0.044*
C2	0.1546 (5)	0.11014 (11)	0.6508 (2)	0.0272 (4)
C3	0.2415 (6)	0.07519 (12)	0.8036 (3)	0.0350 (5)
H3A	0.3394	0.0287	0.8108	0.042*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.0452 (4)	0.0289 (3)	0.0240 (3)	0.0027 (2)	0.0109 (2)	−0.00018 (19)
S2	0.0434 (3)	0.0240 (3)	0.0371 (3)	0.0027 (2)	0.0089 (2)	−0.0015 (2)
O1	0.0739 (13)	0.0422 (10)	0.0409 (9)	0.0132 (9)	0.0131 (9)	−0.0118 (8)
O2	0.1147 (18)	0.0728 (14)	0.0242 (8)	0.0303 (13)	0.0172 (10)	0.0074 (8)
N1	0.0536 (12)	0.0423 (11)	0.0253 (9)	0.0038 (9)	0.0077 (8)	−0.0044 (8)
C1	0.0453 (13)	0.0320 (11)	0.0330 (11)	0.0006 (9)	0.0087 (10)	0.0071 (9)
C2	0.0317 (11)	0.0229 (9)	0.0270 (9)	−0.0031 (8)	0.0066 (8)	−0.0041 (7)
C3	0.0504 (13)	0.0307 (11)	0.0243 (9)	0.0044 (9)	0.0095 (9)	−0.0041 (8)

Geometric parameters (Å, º)

S1—C2	1.735 (2)	N1—C3	1.406 (3)
S1—C1	1.817 (2)	C1—H1A	0.9700
S2—C2	1.728 (2)	C1—H1B	0.9700
S2—C1	1.821 (2)	C2—C3	1.344 (3)
O1—N1	1.244 (3)	C3—H3A	0.9300
O2—N1	1.244 (2)
C2—S1—C1	82.8 (1)	S2—C1—H1B	112.9
C2—S2—C1	82.9 (1)	H1A—C1—H1B	110.3
O2—N1—O1	122.3 (2)	C3—C2—S2	131.0 (2)
O2—N1—C3	118.5 (2)	C3—C2—S1	128.7 (2)
O1—N1—C3	119.2 (2)	S2—C2—S1	100.4 (1)
S1—C1—S2	94.00 (1)	C2—C3—N1	118.9 (2)
S1—C1—H1A	112.9	C2—C3—H3A	120.5
S2—C1—H1A	112.9	N1—C3—H3A	120.5
S1—C1—H1B	112.9
C2—S1—C1—S2	−1.10 (10)	C1—S1—C2—S2	1.17 (10)
C2—S2—C1—S1	1.10 (10)	S2—C2—C3—N1	−0.4 (4)
C1—S2—C2—C3	178.9 (2)	S1—C2—C3—N1	179.70 (17)
C1—S2—C2—S1	−1.17 (10)	O2—N1—C3—C2	−177.5 (2)
C1—S1—C2—C3	−178.9 (2)	O1—N1—C3—C2	2.3 (4)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C3—H3A···O2^i	0.93	2.49	3.387 (3)	163

Symmetry code: (i) −x+1, −y, −z+2.