A solid-state oxidation of 1,1,3,3-tetra­methyl­guanidinium 4-methyl­benzene­sulfinate to 1,1,3,3-tetra­methyl­guanidinium 4-methyl­benzenesulfonate

The organic acid–base complex 1,1,3,3-tetra­methyl­guanidinium 4-methyl­benzene­sulfonate, C₅H₁₄N₃⁺·C₇H₇O₃S⁻, was obtained from the corresponding 1,1,3,3-tetra­methyl­guani­din­ium 4-methyl­benzene­sulfinate complex, C₅H₁₄N₃⁺·C₇H₇O₂S⁻, by solid-state oxidation in air. Comparison of the two crystal structures reveals similar packing arrangements in the monoclinic space group P2₁/c, with centrosymmetric 2:2 tetra­mers being connected by four strong N—H...O=S hydrogen bonds between the imine N atoms of two 1,1,3,3-tetra­methyl­guanidinium bases and the O atoms of two acid mol­ecules.

S1. Comment

The complex formed between 1,1,3,3-tetramethylguanidinium and 4-methylbenzenesulfinate, (I), was investigated in order to provide information relevant to the mechanistic proposal for the reaction of ditosylhydrazine with an α-bromoacetamide, in the presence of a base, which produces an α-diazoacetamide. In the original publication (Toma et al. 2007) concerning the preparation of α-diazoesters, the authors proposed that two molecules of p-toluenesulfinate are produced as the diazo group is installed on the α C atom. The obtained crystal structure (Fig. 1a) thus supports this element in their mechanistic proposal.

The structure of the corresponding sulfonate, (II), shown in Fig. 1(b), was determined to support the identification of the second counterion observed in mass spectrometry (ESI/TOF-) and ¹H NMR of (I), after being exposed to air, as p-toluenesulfonate. For an additional report mentioning the facile oxidation of p-toluenesulfinates, see Whitmore & Hamilton (1922).

The structures of (I) and (II) are very similar with respect to both molecular geometry and crystal packing (Fig. 2). Both form characteristic 2:2 tetramers, giving rise to second-level R₄⁴(12) ring motifs [for graph-set notation, see Etter et al. (1990) and Bernstein et al. (1995)]. The tables of crystallographic data reveal increases in the lengths of the b and c axes significant enough to result in a decrease in density upon oxidation from 1.277 Mg m^-3 for (I) to 1.270 Mg m^-3 for (II) [data for (II) were collected at room temperature due to a temporary malfunction of the low-temperature device, a factor also contributing to a lower density than for (I)]. On a detailed level, there are also small voids in the structure of (II) that are not indicated in the structure of (I) (Fig. 2). Accordingly, the manner in which oxygen can penetrate the crystal structure of (I) to yield (II) in a solid-state oxidation is unclear.

In the Cambridge Structural Database (CSD, Version 5.34 of November 2012; Allen 2002) there are 18 structures containing the 1,1,3,3-tetramethylguanidinium cation, of which seven form 2:2 cyclic adducts as shown in Fig. 3. In the structures of (I) and (II), each acceptor atom is involved in only a single strong hydrogen bond, but there are also cases of twofold acceptors, as seen for the dihydrogenphosphate salt in Fig. 3(a) (Criado et al., 2000), where the graph set is R₄⁴(8) rather than R₄⁴(12). The ring system may, as for (I) and (II), have a central centre of symmetry, giving essentially coplanar guanidinium cations, or they may be folded, as seen in Fig. 3(b) for the complex with propanoic acid (King et al., 2011).

The 4-methylbenzenesulfinate (I), or p-toluenesulfinate, occurs in only two previous entries in the CSD (Thirupathi et al., 2003; Betz & Gerber, 2011). Two further structures have 4-nitro in place of 4-methyl substituents (Nakazawa et al., 2011; Brito et al., 2006), while the parent benzenesulfinate accounts for a single entry (McDonald et al., 2010). One of the nitro-substituted structures (Brito et al., 2006) forms a hydrogen-bonded ring system related to (I) (Fig. 3c). In contrast with the sulfinate, the 4-methylbenzenesulfonate is quite a common anion in the CSD, with close to 600 structures reported to date, of which 310 are classified as `organic' (i.e. not `metallo-organic'). In the latter group, 55 structures contain R₄⁴(12) ring motifs with N donors. Most of them have charged amino groups as donors; Fig. 3(d) shows one of the few occurrences of an Nsp² atom as donor (Blaton et al., 1995).

Related literature

For related literature, see: Allen (2002); American (2008); Bernstein et al. (1995); Betz & Gerber (2011); Blaton et al. (1995); Brito et al. (2006); Criado et al. (2000); Etter et al. (1990); Kaupang (2010); King et al. (2011); McDonald et al. (2010); Nakazawa et al. (2011); Thirupathi et al. (2003); Toma et al. (2007); Vilas & Tojo (2010); Whitmore & Hamilton (1922).

S2. Experimental

Acid–base complex (I) precipitated from the reaction mixture (in tetrahydrofuran, THF) during the transformation of an α-bromoacetamide into an α-diazoacetamide, using the reagent ditosylhydrazine and the base 1,1,3,3-tetramethylguanidine, a reaction that generates 2 molar equivalents of p-toluenesulfinate (Kaupang, 2010; Toma et al., 2007). The complex is soluble in dichloromethane, acetonitrile, methanol and water, poorly soluble in THF, and nearly insoluble in diethyl ether. No previous reports of this complex were found in the Chemical Abstracts Service (CAS; American Chemical Society, 2008).

Complex (II) was obtained by oxidation of (I) in air over a period of approximately 72 h, after which time the resulting powder was submitted to crystallization. For a previously reported synthesis of (II), see Vilas & Tojo (2010). A saturated solution of freshly precipitated (I) in acetonitrile was placed in a beaker, which was covered with Parafilm and stored in the dark at 277 K (refrigerator) for a period of approximately 12 h, during which time multiple clusters of thick colourless needles appeared. A sample of complex (I), as it precipitated from the above-mentioned reaction (colourless powder), was exposed to air for a period of approximately 72 h. A solution of the resulting powder (4.8 mg) in anhydrous dichloromethane (500 µl) was placed in a 2.5 ml vial, which was then capped and a pinhole (0.3 mm) made in the cap to allow for vapour diffusion. This vial was placed inside a 25 ml vial containing diethyl ether (5 ml), which was subsequently capped and stored in the dark at ambient temperature for approximately 48 h, affording thin colourless needles of (II).

S3. Refinement

During refinement of (II), it became clear that atom O1 had an occupancy less than unity. This meant that (II) is actually a solid-state mixture between the oxidized sulfonate [occupancy 0.816 (12)] and the original reduced sulfinate form [occupancy 0.184 (12)]. No special measures were needed to account for this fact during normal anisotropic refinement. Positional parameters were refined for H atoms of the tetramethylguanidinium NH₂ group. Other H atoms were introduced at theoretical positions, with C—H = 0.95/0.93 (aromatic) or 0.98/0.96 (methyl) Å for (I)/(II) and with free refinement of methyl-group rotation. U_iso(H) = 1.2U_eq of the carrier atom or 1.5U_eq for methyl groups.

Computing details

For both compounds, data collection: APEX2 (Bruker, 2007); cell refinement: SAINT-Plus (Bruker, 2007); data reduction: SAINT-Plus (Bruker, 2007); 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).

Figures

	Fig. 1. The asymmetric units of (a) (I) and (b) (II), showing the atom-numbering schemes. Displacement ellipsoids, drawn at the 50% probability level, reflect the data-collection temperatures of 105 and 293 K, respectively. Dashed lines indicate hydrogen bonds [Added text OK?]. Only the major component (the sulfonate) is shown for (II).
	Fig. 2. Crystal packing arrangements for (a) (I) and (b) (II). H atoms not involved in hydrogen bonds (indicated as dashed lines) have been omitted for clarity. The large shape in (b) represents a small void, calculated by Mercury (Macrae et al., 2008) using a 0.9 Å probe radius and 0.5 Å grid spacing. In (I), there are three π–π interactions with (C–)H···C distances in the range 2.80–2.86 Å. The corresponding distances in (II) are slightly longer and cover the range 2.86–3.06 Å. Only the major component (the sulfonate) is shown for (II).
	Fig. 3. Second-level R2^2(12) or R2^2(12) hydrogen-bond motifs in (a) 1,1,3,3-tetramethylguanidinium dihydrogenorthophosphate (Criado et al., 2000), (b) 1,1,3,3-tetramethylguanidinium propionate (King et al., 2011), (c) dicyclohexylammonium 4-nitrophenylsulfinate (Brito et al., 2006) and (d) N-[2-(3-methoxyphenoxy)propyl]-m-tolylacetamidinium p-toluenesulfonate monohydrate (Blaton et al., 1995). In (d) the water molcule has been omitted, while substituted phenyl rings are shown as small spheres for clarity. The small circles in (a), (c) and (d) indicate crystallographic inversion centres.

(I) 1,1,3,3-Tetramethylguanidinium 4-methylbenzenesulfinate

Crystal data

C5H14N3^+·C7H7O2S^−	F(000) = 584
Mr = 271.38	Dx = 1.277 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 7132 reflections
a = 11.0959 (8) Å	θ = 2.2–28.2°
b = 7.4038 (5) Å	µ = 0.23 mm^−1
c = 17.1944 (13) Å	T = 105 K
β = 92.115 (1)°	Needle, colourless
V = 1411.59 (18) Å^3	0.6 × 0.4 × 0.3 mm
Z = 4

Data collection

Bruker APEXII CCD area-detector diffractometer	3375 independent reflections
Radiation source: fine-focus sealed tube	3026 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.017
Detector resolution: 8.3 pixels mm^-1	θmax = 28.3°, θmin = 1.8°
Sets of exposures each taken over 0.5° ω rotation scans	h = −14→14
Absorption correction: multi-scan (SADABS; Bruker, 2007)	k = −9→9
Tmin = 0.857, Tmax = 0.934	l = −20→22
11987 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)] = 0.030	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.085	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	w = 1/[σ^2(Fo^2) + (0.044P)^2 + 0.5937P] where P = (Fo^2 + 2Fc^2)/3
3375 reflections	(Δ/σ)max < 0.001
174 parameters	Δρmax = 0.45 e Å^−3
0 restraints	Δρmin = −0.25 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 > 2σ(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	0.30075 (2)	0.51868 (4)	0.394666 (15)	0.01692 (9)
O1	0.37108 (8)	0.68587 (13)	0.37629 (6)	0.0304 (2)
O2	0.28844 (7)	0.49282 (11)	0.48104 (5)	0.02002 (18)
N1	0.40988 (9)	0.19986 (14)	0.55558 (6)	0.0195 (2)
H11	0.4796 (14)	0.227 (2)	0.5750 (9)	0.023*
H12	0.3712 (14)	0.282 (2)	0.5295 (9)	0.023*
N2	0.39917 (8)	−0.06040 (13)	0.63074 (6)	0.0177 (2)
N3	0.25970 (9)	−0.01043 (13)	0.52913 (6)	0.0196 (2)
C1	0.35733 (10)	0.04483 (15)	0.57169 (6)	0.0166 (2)
C2	0.47598 (10)	0.01253 (16)	0.69412 (7)	0.0194 (2)
H21	0.5608	−0.0074	0.6827	0.027 (4)*
H22	0.4576	−0.0485	0.7429	0.025 (4)*
H23	0.4610	0.1423	0.6993	0.024 (4)*
C3	0.39775 (11)	−0.25785 (16)	0.62565 (7)	0.0223 (2)
H31	0.3636	−0.2946	0.5747	0.033*
H32	0.3484	−0.3071	0.6667	0.033*
H33	0.4803	−0.3040	0.6321	0.033*
C4	0.16244 (11)	−0.11332 (18)	0.56260 (8)	0.0258 (3)
H41	0.1567	−0.2321	0.5376	0.039*
H42	0.0861	−0.0483	0.5542	0.039*
H43	0.1791	−0.1288	0.6186	0.039*
C5	0.23347 (12)	0.05848 (17)	0.45081 (7)	0.0254 (3)
H51	0.2005	−0.0390	0.4179	0.038*
H52	0.3079	0.1041	0.4289	0.038*
H53	0.1745	0.1567	0.4531	0.038*
C6	0.14936 (9)	0.58534 (15)	0.36374 (6)	0.0153 (2)
C7	0.13042 (10)	0.68386 (16)	0.29538 (7)	0.0195 (2)
H71	0.1973	0.7237	0.2670	0.023*
C8	0.05119 (10)	0.53005 (15)	0.40548 (6)	0.0162 (2)
H81	0.0637	0.4624	0.4520	0.019*
C9	0.01368 (10)	0.72398 (16)	0.26864 (7)	0.0210 (2)
H91	0.0014	0.7899	0.2216	0.025*
C10	−0.06587 (10)	0.57360 (15)	0.37931 (6)	0.0171 (2)
H101	−0.1325	0.5382	0.4090	0.021*
C11	−0.08581 (10)	0.66839 (15)	0.31013 (7)	0.0175 (2)
C12	−0.21214 (10)	0.70739 (19)	0.27933 (7)	0.0256 (3)
H121	−0.2703	0.6611	0.3159	0.038*
H122	−0.2254	0.6483	0.2287	0.038*
H123	−0.2228	0.8381	0.2733	0.038*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.01412 (14)	0.01972 (15)	0.01683 (15)	−0.00025 (9)	−0.00092 (10)	0.00090 (10)
O1	0.0198 (4)	0.0338 (5)	0.0372 (5)	−0.0098 (4)	−0.0060 (4)	0.0139 (4)
O2	0.0216 (4)	0.0222 (4)	0.0159 (4)	0.0018 (3)	−0.0034 (3)	0.0012 (3)
N1	0.0182 (4)	0.0194 (5)	0.0206 (5)	−0.0018 (4)	−0.0041 (4)	0.0035 (4)
N2	0.0201 (4)	0.0153 (4)	0.0175 (5)	0.0000 (3)	−0.0030 (4)	0.0006 (4)
N3	0.0213 (5)	0.0190 (5)	0.0182 (5)	−0.0032 (4)	−0.0044 (4)	0.0015 (4)
C1	0.0167 (5)	0.0175 (5)	0.0156 (5)	0.0015 (4)	0.0005 (4)	−0.0015 (4)
C2	0.0194 (5)	0.0220 (6)	0.0167 (5)	−0.0003 (4)	−0.0037 (4)	0.0012 (4)
C3	0.0280 (6)	0.0159 (5)	0.0227 (6)	0.0023 (4)	−0.0011 (5)	0.0007 (4)
C4	0.0224 (6)	0.0252 (6)	0.0295 (6)	−0.0069 (5)	−0.0041 (5)	0.0030 (5)
C5	0.0344 (6)	0.0212 (6)	0.0198 (6)	−0.0033 (5)	−0.0104 (5)	0.0014 (5)
C6	0.0150 (5)	0.0153 (5)	0.0153 (5)	−0.0006 (4)	−0.0017 (4)	−0.0015 (4)
C7	0.0185 (5)	0.0218 (5)	0.0184 (5)	−0.0026 (4)	0.0021 (4)	0.0039 (4)
C8	0.0188 (5)	0.0175 (5)	0.0124 (5)	−0.0002 (4)	−0.0001 (4)	0.0009 (4)
C9	0.0229 (5)	0.0226 (6)	0.0175 (5)	0.0007 (4)	−0.0011 (4)	0.0065 (4)
C10	0.0163 (5)	0.0190 (5)	0.0161 (5)	−0.0005 (4)	0.0018 (4)	−0.0006 (4)
C11	0.0175 (5)	0.0173 (5)	0.0176 (5)	0.0016 (4)	−0.0010 (4)	−0.0002 (4)
C12	0.0184 (5)	0.0334 (7)	0.0248 (6)	0.0041 (5)	−0.0023 (4)	0.0053 (5)

Geometric parameters (Å, º)

S1—O1	1.5031 (9)	C4—H42	0.9800
S1—O2	1.5085 (9)	C4—H43	0.9800
S1—C6	1.8116 (11)	C5—H51	0.9800
N1—C1	1.3215 (15)	C5—H52	0.9800
N1—H11	0.856 (16)	C5—H53	0.9800
N1—H12	0.862 (16)	C6—C8	1.3882 (15)
N2—C1	1.3486 (14)	C6—C7	1.3926 (15)
N2—C3	1.4645 (15)	C7—C9	1.3906 (16)
N2—C2	1.4618 (14)	C7—H71	0.9500
N3—C1	1.3483 (14)	C8—C10	1.3966 (15)
N3—C4	1.4567 (15)	C8—H81	0.9500
N3—C5	1.4594 (15)	C9—C11	1.3983 (16)
C2—H21	0.9800	C9—H91	0.9500
C2—H22	0.9800	C10—C11	1.3916 (16)
C2—H23	0.9800	C10—H101	0.9500
C3—H31	0.9800	C11—C12	1.5080 (15)
C3—H32	0.9800	C12—H121	0.9800
C3—H33	0.9800	C12—H122	0.9800
C4—H41	0.9800	C12—H123	0.9800
O1—S1—O2	112.21 (5)	H42—C4—H43	109.5
O1—S1—C6	101.36 (5)	N3—C5—H51	109.5
O2—S1—C6	101.94 (5)	N3—C5—H52	109.5
C1—N1—H11	121.6 (10)	H51—C5—H52	109.5
C1—N1—H12	120.6 (10)	N3—C5—H53	109.5
H11—N1—H12	117.4 (14)	H51—C5—H53	109.5
C1—N2—C3	121.93 (10)	H52—C5—H53	109.5
C1—N2—C2	121.53 (10)	C8—C6—C7	119.60 (10)
C3—N2—C2	114.71 (9)	C8—C6—S1	120.31 (8)
C1—N3—C4	122.43 (10)	C7—C6—S1	119.99 (8)
C1—N3—C5	121.58 (10)	C6—C7—C9	120.04 (10)
C4—N3—C5	114.96 (10)	C6—C7—H71	120.0
N1—C1—N2	121.16 (10)	C9—C7—H71	120.0
N1—C1—N3	120.11 (10)	C6—C8—C10	120.23 (10)
N2—C1—N3	118.74 (10)	C6—C8—H81	119.9
N2—C2—H21	109.5	C10—C8—H81	119.9
N2—C2—H22	109.5	C11—C9—C7	120.78 (10)
H21—C2—H22	109.5	C11—C9—H91	119.6
N2—C2—H23	109.5	C7—C9—H91	119.6
H21—C2—H23	109.5	C11—C10—C8	120.56 (10)
H22—C2—H23	109.5	C11—C10—H101	119.7
N2—C3—H31	109.5	C8—C10—H101	119.7
N2—C3—H32	109.5	C10—C11—C9	118.75 (10)
H31—C3—H32	109.5	C10—C11—C12	120.87 (10)
N2—C3—H33	109.5	C9—C11—C12	120.37 (10)
H31—C3—H33	109.5	C11—C12—H121	109.5
H32—C3—H33	109.5	C11—C12—H122	109.5
N3—C4—H41	109.5	H121—C12—H122	109.5
N3—C4—H42	109.5	C11—C12—H123	109.5
H41—C4—H42	109.5	H121—C12—H123	109.5
N3—C4—H43	109.5	H122—C12—H123	109.5
H41—C4—H43	109.5
C3—N2—C1—N1	−143.62 (11)	O2—S1—C6—C7	156.58 (9)
C2—N2—C1—N1	20.17 (17)	C8—C6—C7—C9	−0.98 (17)
C3—N2—C1—N3	36.74 (16)	S1—C6—C7—C9	175.39 (9)
C2—N2—C1—N3	−159.47 (10)	C7—C6—C8—C10	−0.28 (17)
C4—N3—C1—N1	−146.26 (11)	S1—C6—C8—C10	−176.65 (8)
C5—N3—C1—N1	21.57 (17)	C6—C7—C9—C11	0.78 (18)
C4—N3—C1—N2	33.39 (16)	C6—C8—C10—C11	1.78 (17)
C5—N3—C1—N2	−158.79 (11)	C8—C10—C11—C9	−1.96 (17)
O1—S1—C6—C8	−142.95 (9)	C8—C10—C11—C12	176.76 (11)
O2—S1—C6—C8	−27.07 (10)	C7—C9—C11—C10	0.69 (18)
O1—S1—C6—C7	40.70 (10)	C7—C9—C11—C12	−178.04 (11)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H11···O1^i	0.856 (16)	1.938 (16)	2.7902 (13)	173.4 (15)
N1—H12···O2	0.862 (16)	1.977 (16)	2.8347 (13)	172.5 (14)

Symmetry code: (i) −x+1, −y+1, −z+1.

(II) 1,1,3,3-Tetramethylguanidinium 4-methylbenzenesulfonate

Crystal data

C5H14N3^+·C7H7O2.82S^−	F(000) = 610.1
Mr = 284.44	Dx = 1.270 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2504 reflections
a = 11.185 (3) Å	θ = 2.3–24.7°
b = 7.648 (2) Å	µ = 0.23 mm^−1
c = 17.415 (5) Å	T = 296 K
β = 93.169 (4)°	Needle, colourless
V = 1487.5 (8) Å^3	0.8 × 0.3 × 0.2 mm
Z = 4

Data collection

Bruker APEXII CCD area-detector diffractometer	2615 independent reflections
Radiation source: fine-focus sealed tube	1587 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.045
Detector resolution: 8.3 pixels mm^-1	θmax = 25.0°, θmin = 1.8°
Sets of exposures each taken over 0.5° ω rotation scans	h = −13→13
Absorption correction: multi-scan (SADABS; Bruker, 2007)	k = −9→9
Tmin = 0.710, Tmax = 0.956	l = −20→20
10043 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)] = 0.063	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.155	H atoms treated by a mixture of independent and constrained refinement
S = 1.08	w = 1/[σ^2(Fo^2) + (0.0241P)^2 + 2.8813P] where P = (Fo^2 + 2Fc^2)/3
2615 reflections	(Δ/σ)max < 0.001
187 parameters	Δρmax = 0.33 e Å^−3
0 restraints	Δρmin = −0.38 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 > 2σ(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	Occ. (<1)
S1	0.29495 (10)	0.56175 (19)	0.40703 (8)	0.0653 (4)
O1	0.3460 (4)	0.4551 (9)	0.3592 (3)	0.142 (3)	0.816 (12)
O2	0.3510 (3)	0.7310 (5)	0.4107 (3)	0.1321 (19)
O3	0.2812 (3)	0.4933 (4)	0.48344 (18)	0.0768 (10)
N1	0.4054 (3)	0.1976 (6)	0.5527 (2)	0.0648 (11)
H11	0.370 (4)	0.274 (6)	0.531 (3)	0.078*
H12	0.483 (4)	0.215 (6)	0.571 (2)	0.078*
N2	0.3989 (3)	−0.0456 (5)	0.62949 (19)	0.0543 (9)
N3	0.2466 (3)	0.0096 (5)	0.5376 (2)	0.0606 (10)
C9	−0.0649 (4)	0.5739 (6)	0.3758 (2)	0.0580 (12)
H91	−0.1295	0.5335	0.4022	0.070*
C11	0.0499 (3)	0.5440 (6)	0.4053 (2)	0.0536 (11)
H111	0.0618	0.4820	0.4511	0.064*
C1	0.3513 (3)	0.0534 (6)	0.5729 (2)	0.0500 (10)
C12	0.1465 (3)	0.6038 (5)	0.3686 (2)	0.0464 (10)
C7	−0.0852 (4)	0.6621 (6)	0.3081 (2)	0.0546 (11)
C10	0.1274 (4)	0.6953 (6)	0.3016 (3)	0.0661 (13)
H101	0.1920	0.7386	0.2762	0.079*
C5	0.4852 (4)	0.0232 (8)	0.6870 (3)	0.0744 (15)
H51	0.4738	−0.0319	0.7356	0.11 (2)*
H52	0.4742	0.1471	0.6918	0.091 (18)*
H53	0.5648	−0.0001	0.6718	0.12 (2)*
C3	0.2110 (5)	0.0756 (7)	0.4608 (3)	0.0843 (17)
H31	0.1704	−0.0151	0.4315	0.126*
H32	0.2808	0.1113	0.4353	0.126*
H33	0.1583	0.1737	0.4652	0.126*
C6	−0.2104 (4)	0.6907 (8)	0.2732 (3)	0.0868 (17)
H61	−0.2260	0.8139	0.2691	0.130*
H62	−0.2673	0.6377	0.3054	0.130*
H63	−0.2174	0.6387	0.2230	0.130*
C2	0.1546 (4)	−0.0843 (7)	0.5762 (3)	0.0931 (18)
H21	0.1468	−0.2001	0.5553	0.140*
H22	0.0797	−0.0237	0.5685	0.140*
H23	0.1762	−0.0911	0.6302	0.140*
C8	0.0122 (4)	0.7232 (7)	0.2719 (3)	0.0698 (14)
H81	0.0003	0.7851	0.2261	0.084*
C4	0.3906 (4)	−0.2361 (6)	0.6268 (3)	0.0763 (15)
H41	0.3509	−0.2713	0.5790	0.114*
H42	0.3458	−0.2767	0.6687	0.114*
H43	0.4696	−0.2854	0.6309	0.114*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.0446 (6)	0.0761 (9)	0.0743 (9)	−0.0034 (7)	−0.0040 (5)	0.0091 (7)
O1	0.080 (4)	0.209 (7)	0.135 (5)	0.063 (4)	−0.022 (3)	−0.074 (5)
O2	0.063 (2)	0.098 (3)	0.229 (5)	−0.038 (2)	−0.049 (3)	0.067 (3)
O3	0.068 (2)	0.085 (2)	0.075 (2)	−0.0006 (18)	−0.0194 (17)	0.0229 (19)
N1	0.048 (2)	0.064 (3)	0.081 (3)	−0.009 (2)	−0.011 (2)	0.021 (2)
N2	0.051 (2)	0.055 (2)	0.056 (2)	0.0026 (18)	−0.0045 (16)	0.0063 (19)
N3	0.056 (2)	0.058 (2)	0.066 (2)	−0.0085 (18)	−0.0147 (18)	0.0075 (19)
C9	0.046 (2)	0.068 (3)	0.061 (3)	0.000 (2)	0.007 (2)	0.007 (2)
C11	0.052 (2)	0.067 (3)	0.042 (2)	−0.001 (2)	0.0024 (19)	0.014 (2)
C1	0.041 (2)	0.050 (3)	0.058 (3)	0.003 (2)	−0.0030 (19)	−0.002 (2)
C12	0.043 (2)	0.046 (2)	0.050 (2)	−0.0041 (19)	0.0008 (18)	−0.002 (2)
C7	0.056 (3)	0.051 (3)	0.056 (3)	0.006 (2)	−0.004 (2)	−0.003 (2)
C10	0.058 (3)	0.080 (3)	0.060 (3)	−0.006 (3)	0.006 (2)	0.023 (3)
C5	0.063 (3)	0.089 (5)	0.069 (3)	0.001 (3)	−0.018 (3)	0.009 (3)
C3	0.096 (4)	0.064 (3)	0.087 (4)	−0.012 (3)	−0.046 (3)	0.013 (3)
C6	0.064 (3)	0.099 (4)	0.094 (4)	0.017 (3)	−0.022 (3)	0.004 (3)
C2	0.059 (3)	0.090 (4)	0.129 (5)	−0.022 (3)	−0.005 (3)	0.018 (4)
C8	0.071 (3)	0.077 (4)	0.061 (3)	0.002 (3)	−0.005 (3)	0.025 (3)
C4	0.090 (4)	0.059 (3)	0.080 (4)	0.012 (3)	0.000 (3)	0.011 (3)

Geometric parameters (Å, º)

S1—O1	1.318 (5)	C7—C8	1.372 (6)
S1—O2	1.438 (4)	C7—C6	1.511 (6)
S1—O3	1.446 (3)	C10—C8	1.378 (6)
S1—O3	1.446 (3)	C10—H101	0.9300
S1—C12	1.785 (4)	C5—H51	0.9600
N1—C1	1.315 (5)	C5—H52	0.9600
N1—H11	0.79 (5)	C5—H53	0.9600
N1—H12	0.92 (5)	C3—H31	0.9600
N2—C1	1.330 (5)	C3—H32	0.9600
N2—C5	1.452 (5)	C3—H33	0.9600
N2—C4	1.460 (6)	C6—H61	0.9600
N3—C1	1.335 (5)	C6—H62	0.9600
N3—C2	1.450 (6)	C6—H63	0.9600
N3—C3	1.464 (5)	C2—H21	0.9600
C9—C7	1.365 (6)	C2—H22	0.9600
C9—C11	1.376 (5)	C2—H23	0.9600
C9—H91	0.9300	C8—H81	0.9300
C11—C12	1.365 (5)	C4—H41	0.9600
C11—H111	0.9300	C4—H42	0.9600
C12—C10	1.367 (5)	C4—H43	0.9600
O1—S1—O2	112.5 (4)	N2—C5—H51	109.5
O1—S1—O3	115.4 (3)	N2—C5—H52	109.5
O2—S1—O3	110.7 (3)	H51—C5—H52	109.5
O1—S1—C12	107.5 (3)	N2—C5—H53	109.5
O2—S1—C12	104.4 (2)	H51—C5—H53	109.5
O3—S1—C12	105.42 (19)	H52—C5—H53	109.5
O3—S1—C12	105.42 (19)	N3—C3—H31	109.5
C1—N1—H11	122 (4)	N3—C3—H32	109.5
C1—N1—H12	118 (3)	H31—C3—H32	109.5
H11—N1—H12	120 (5)	N3—C3—H33	109.5
C1—N2—C5	121.9 (4)	H31—C3—H33	109.5
C1—N2—C4	121.5 (4)	H32—C3—H33	109.5
C5—N2—C4	115.0 (4)	C7—C6—H61	109.5
C1—N3—C2	122.6 (4)	C7—C6—H62	109.5
C1—N3—C3	121.4 (4)	H61—C6—H62	109.5
C2—N3—C3	115.4 (4)	C7—C6—H63	109.5
C7—C9—C11	120.8 (4)	H61—C6—H63	109.5
C7—C9—H91	119.6	H62—C6—H63	109.5
C11—C9—H91	119.6	N3—C2—H21	109.5
C12—C11—C9	121.0 (4)	N3—C2—H22	109.5
C12—C11—H111	119.5	H21—C2—H22	109.5
C9—C11—H111	119.5	N3—C2—H23	109.5
N1—C1—N2	120.3 (4)	H21—C2—H23	109.5
N1—C1—N3	119.5 (4)	H22—C2—H23	109.5
N2—C1—N3	120.2 (4)	C7—C8—C10	121.6 (4)
C11—C12—C10	118.8 (4)	C7—C8—H81	119.2
C11—C12—S1	120.5 (3)	C10—C8—H81	119.2
C10—C12—S1	120.7 (3)	N2—C4—H41	109.5
C9—C7—C8	117.8 (4)	N2—C4—H42	109.5
C9—C7—C6	121.7 (4)	H41—C4—H42	109.5
C8—C7—C6	120.5 (4)	N2—C4—H43	109.5
C12—C10—C8	120.0 (4)	H41—C4—H43	109.5
C12—C10—H101	120.0	H42—C4—H43	109.5
C8—C10—H101	120.0
C7—C9—C11—C12	1.0 (7)	O3—S1—C12—C11	−10.9 (4)
C5—N2—C1—N1	20.9 (6)	O3—S1—C12—C11	−10.9 (4)
C4—N2—C1—N1	−143.7 (5)	O1—S1—C12—C10	−66.7 (5)
C5—N2—C1—N3	−157.2 (4)	O2—S1—C12—C10	52.9 (4)
C4—N2—C1—N3	38.1 (6)	O3—S1—C12—C10	169.6 (4)
C2—N3—C1—N1	−148.1 (5)	O3—S1—C12—C10	169.6 (4)
C3—N3—C1—N1	22.9 (7)	C11—C9—C7—C8	−1.6 (7)
C2—N3—C1—N2	30.0 (6)	C11—C9—C7—C6	177.8 (4)
C3—N3—C1—N2	−158.9 (4)	C11—C12—C10—C8	−0.9 (7)
C9—C11—C12—C10	0.2 (7)	S1—C12—C10—C8	178.5 (4)
C9—C11—C12—S1	−179.2 (3)	C9—C7—C8—C10	0.9 (7)
O1—S1—C12—C11	112.7 (5)	C6—C7—C8—C10	−178.5 (5)
O2—S1—C12—C11	−127.6 (4)	C12—C10—C8—C7	0.4 (8)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H12···O2^i	0.92 (5)	1.91 (5)	2.817 (5)	169 (4)
N1—H11···O3	0.79 (5)	2.10 (5)	2.884 (5)	174 (5)

Symmetry code: (i) −x+1, −y+1, −z+1.