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Acta Cryst. (2009). E65, o16    [ doi:10.1107/S1600536808038828 ]

N,N'-(2,2'-Dithiodi-o-phenylene)bis(furan-2-carboxamide)

J. Raftery, H. Lallbeeharry, M. G. Bhowon, S. J. Laulloo and J. A. Joule

Abstract top

The reaction of 2,2'-dithiobis(benzenamine) with furan-2-carbonyl chloride produced the bis-amide title compound, C22H16N2O4S2, which, in the crystal, formed a helix; the structure consists of two planar furanoylbenzenamines related by an improper rotation of 96.3° about the S-S bond. The N-furanoylbenzenamine units are planar (maximum deviations = 0.316 and 0.132 Å). Each electron-deficient acylfuran stacks (centroid-centroid separations of the two pairs of [pi]-[pi] stacked aromatic rings are 3.918 and 3.953 Å) with the electron-rich benzenamine of the other N-furanoylbenzenamine unit, leading to a spiral structure. The conformation is stabilized by two bifurcated intramolecular N-H...(O,S) interactions.

Comment top

We have been interested in the synthesis and properties of potential ligands which can be prepared from 2,2'-dithiobis(benzenamine). From this starting material, one can envisage the preparation of multidentate chelating agents having nitrogen, oxygen and sulfur donor atoms of relevance for the study of various mode of coordination (Okachi et al., 1985; Bhowon et al., 2001; Jhaumeer Laulloo & Bhowon, 2003; Bhowon et al., 2007; Nag et al., 2001; Uma & Palanaindavar, 1993; Bhowon et al., 2005). In the present work 2,2'-dithiobis(benzenamine) N,N'-bis(furan-2-carboxamide) was synthesized (Scheme 1) with a view to examining the stereochemistry of the compound.

The structure (Figure 1) proved to be of considerable interest in adopting a helical structure, the formation of which is driven, we suggest, by the interaction of the furan and benzene units, through space. A furan ring system is normally considered electron-rich, but in this case, carrying a 2-carboxamide unit, it is electron-deficient. The benzene rings, on the other hand, each with a sulfur and a nitrogen substituent, are electron-rich, compared with an unsubstituted benzene. We suggest that interaction of these electronically opposed π-systems, through space, orients the molecule in a helix such that one acyl-furan stacks above the electron-rich benzene located at the other end of the molecule, and the other acyl-furan stacks below the other benzene ring. The second diagram, Figure 2, is a view along the S—S bond. It clearly shows the helical nature of the molecule: the molecule shown has an anticlockwise sense of twist.

The furan ring (C19—C22 and O4), the amide unit (C18, O3, N2), the benzene ring (C12—C17), and S2 are oriented in one plane, which we use as a reference plane (plane 1) (see below). The other benzene ring (C1—C6) (plane 2), the other furan ring (C8—C11 and O2) (plane 3), and the other amide unit (C7, O1, N1) (plane 4), comprise three planes at small dihedral angles one with the other: 2 versus 3 = 18.51°; 3 versus 4 = 13.75°; 2 versus 4 = 11.77°.

The extent to which the reference plane 1 and the three planes of the other 'half' of the molecule are not parallel is small. Quantitatively, this can be measured by the dihedral angles between plane 1 and other three planes: 1 versus 2 = 23.05°; 1 versus 3 = 8.78°; 1 versus 4 = 6.45°. Thus, to a close approximation, the molecule consists of two units (one planar and one close to planar) which are nearly parallel, the largest deviation from which being 23.05° (between the two benzene rings: the extent to which the planes of these can be parallel is constrained by their attachment to the disulfide unit). At the closest points, the distances between the two pairs of stacked furan and benzene aromatic rings are 2.35Å and 3.56Å.

Related literature top

For the preparation of multidentate chelating agents using 2,2'-dithiobis(benzenamine) as starting

material, see: Bhowon et al. (2001, 2005, 2007); Nag et al. (2001); Okachi et al. (1985); Uma & Palanaindavar (1993); Jhaumeer & Bhowon (2003).

Experimental top

A solution of 2-furoyl chloride (0.52 g, 4 mmol) in dioxane (25 ml) was stirred with triethylamine (0.25 ml) for 30 min. To the reaction mixture a solution of bis(2-aminophenyl disulfide) (0.50 g, 2 mmol) in dioxane (15 ml) was added dropwise and the mixture was stirred at room temperature for 3 h. The solution was filtered and on keeping the filtrate for 48 h a solid formed, which was filtered off, the solid washed with water and dried and gave the bis-amide (0.75 g, 84%) as yellow crystals, mp 434 K; δH (250 MHz, DMSO-d6) 6.52-6.54 (2H, m), 6.90-6.97 (2H, t, J 7,1 Hz), 7.17-7.18 (2H, d, J 7 Hz), 7.24-7.30 (2H, dt, J 7,1 Hz), 7.40-7.50 (4H, m), 8.45 (2H, d, J 8 Hz), 9.30 (2H, s); δC (250 MHz, DMSO-d6) 113.4, 115.5, 120.2, 122.8, 124.1, 132.2, 136.7, 139.6, 145.0, 147.6, 155.7; m/z (FAB) 459 (M+Na), 437 (M+H).

Refinement top

The structure was solved by direct methods. The non-hydrogen atoms were refined anisotropically. H atoms were included in calculated positions with C—H lengths of 0.95(CH), 0.99(CH2) & 0.98(CH3)Å; Uiso(H) values were fixed at 1.2Ueq(C) except for CH3 where it was 1.5Ueq(C).

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SMART (Bruker, 2001); data reduction: SAINT (Bruker, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. View of (I) (50% probability displacement ellipsoids).
[Figure 2] Fig. 2. View of (I) along the S—S bond showing the sense of twist (50% probability displacement ellipsoids).
[Figure 3] Fig. 3. The formation of the title compound.
N,N'-(2,2'-Dithiodi-o-phenylene)bis(furan-2-carboxamide) top
Crystal data top
C22H16N2O4S2Z = 2
Mr = 436.49F(000) = 452
Triclinic, P1Dx = 1.489 Mg m−3
Hall symbol: -P 1Melting point: 434 K
a = 9.6173 (11) ÅMo Kα radiation, λ = 0.71073 Å
b = 9.9210 (11) ÅCell parameters from 1625 reflections
c = 11.9906 (14) Åθ = 2.3–27.2°
α = 109.770 (2)°µ = 0.31 mm−1
β = 103.748 (2)°T = 100 K
γ = 104.643 (2)°Plate, yellow
V = 973.84 (19) Å30.45 × 0.30 × 0.20 mm
Data collection top
Bruker SMART APEX
diffractometer		2911 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.029
graphiteθmax = 28.3°, θmin = 1.9°
φ and ω scansh = −11→12
6177 measured reflectionsk = −12→12
4327 independent reflectionsl = −12→15
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.040Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.076H-atom parameters constrained
S = 0.83 w = 1/[σ2(Fo2) + (0.0233P)2]
where P = (Fo2 + 2Fc2)/3
4327 reflections(Δ/σ)max < 0.001
271 parametersΔρmax = 0.37 e Å−3
0 restraintsΔρmin = −0.30 e Å−3
Crystal data top
C22H16N2O4S2γ = 104.643 (2)°
Mr = 436.49V = 973.84 (19) Å3
Triclinic, P1Z = 2
a = 9.6173 (11) ÅMo Kα radiation
b = 9.9210 (11) ŵ = 0.31 mm−1
c = 11.9906 (14) ÅT = 100 K
α = 109.770 (2)°0.45 × 0.30 × 0.20 mm
β = 103.748 (2)°
Data collection top
Bruker SMART APEX
diffractometer		2911 reflections with I > 2σ(I)
6177 measured reflectionsRint = 0.029
4327 independent reflectionsθmax = 28.3°
Refinement top
R[F2 > 2σ(F2)] = 0.040H-atom parameters constrained
wR(F2) = 0.076Δρmax = 0.37 e Å−3
S = 0.83Δρmin = −0.30 e Å−3
4327 reflectionsAbsolute structure: ?
271 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

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 (Å2) top
xyzUiso*/Ueq
C10.0310 (2)0.5459 (2)0.2881 (2)0.0182 (5)
C2−0.0923 (2)0.4603 (2)0.3075 (2)0.0222 (5)
H2−0.11470.50390.38160.027*
C3−0.1820 (2)0.3115 (3)0.2187 (2)0.0260 (5)
H3−0.26840.25390.23010.031*
C4−0.1452 (2)0.2476 (3)0.1137 (2)0.0254 (5)
H4−0.20470.14400.05470.031*
C5−0.0240 (2)0.3304 (2)0.0922 (2)0.0210 (5)
H5−0.00060.28420.01910.025*
C60.0639 (2)0.4823 (2)0.1783 (2)0.0175 (5)
C70.2528 (2)0.5374 (2)0.0722 (2)0.0191 (5)
C80.3733 (2)0.6694 (2)0.08069 (19)0.0177 (5)
C90.4744 (2)0.6804 (2)0.0208 (2)0.0208 (5)
H90.48660.5977−0.04000.025*
C100.5592 (2)0.8391 (2)0.0659 (2)0.0269 (5)
H100.63940.88360.04120.032*
C110.5045 (2)0.9148 (2)0.1501 (2)0.0276 (5)
H110.54041.02350.19460.033*
C120.4601 (2)0.7032 (2)0.45289 (19)0.0175 (5)
C130.4594 (2)0.5616 (2)0.37237 (19)0.0175 (5)
C140.5733 (2)0.5626 (2)0.3192 (2)0.0205 (5)
H140.57550.46830.26520.025*
C150.6830 (2)0.7001 (2)0.3446 (2)0.0247 (5)
H150.75810.69930.30550.030*
C160.6855 (2)0.8386 (2)0.4259 (2)0.0249 (5)
H160.76290.93230.44410.030*
C170.5740 (2)0.8393 (2)0.4805 (2)0.0221 (5)
H170.57580.93410.53740.027*
C180.3246 (2)0.2766 (2)0.27812 (19)0.0193 (5)
C190.1878 (2)0.1613 (2)0.2705 (2)0.0193 (5)
C200.1276 (2)0.0073 (2)0.2061 (2)0.0259 (5)
H200.1682−0.05480.15370.031*
C21−0.0076 (2)−0.0446 (2)0.2314 (2)0.0267 (5)
H21−0.0758−0.14800.19910.032*
C22−0.0201 (2)0.0812 (2)0.3100 (2)0.0270 (5)
H22−0.10070.08050.34290.032*
N10.18360 (17)0.57613 (18)0.15935 (16)0.0187 (4)
H10.21940.67440.21120.022*
N20.34384 (17)0.42539 (18)0.34788 (15)0.0180 (4)
H2A0.27400.43740.38230.022*
O10.21966 (16)0.40672 (16)−0.00702 (15)0.0279 (4)
O20.39021 (15)0.81377 (15)0.16313 (14)0.0227 (3)
O30.41169 (15)0.23672 (16)0.22600 (14)0.0271 (4)
O40.09859 (15)0.21068 (15)0.33633 (14)0.0229 (4)
S10.14557 (6)0.73663 (6)0.40340 (5)0.02100 (14)
S20.31812 (6)0.70909 (6)0.52536 (5)0.02075 (14)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0161 (11)0.0201 (11)0.0206 (12)0.0088 (9)0.0042 (9)0.0111 (10)
C20.0192 (11)0.0301 (13)0.0244 (13)0.0125 (10)0.0089 (10)0.0160 (11)
C30.0201 (12)0.0325 (14)0.0292 (14)0.0062 (11)0.0092 (11)0.0195 (11)
C40.0221 (12)0.0248 (13)0.0222 (13)0.0013 (10)0.0014 (10)0.0113 (11)
C50.0206 (12)0.0230 (12)0.0165 (12)0.0062 (10)0.0039 (10)0.0081 (10)
C60.0164 (11)0.0209 (12)0.0188 (12)0.0084 (9)0.0049 (9)0.0124 (10)
C70.0189 (11)0.0231 (12)0.0197 (12)0.0112 (10)0.0064 (10)0.0118 (10)
C80.0187 (11)0.0166 (11)0.0154 (11)0.0071 (9)0.0037 (9)0.0051 (9)
C90.0224 (12)0.0223 (12)0.0209 (12)0.0108 (10)0.0101 (10)0.0094 (10)
C100.0249 (13)0.0296 (13)0.0303 (14)0.0088 (11)0.0133 (11)0.0157 (11)
C110.0293 (13)0.0172 (12)0.0301 (14)−0.0004 (10)0.0119 (11)0.0084 (11)
C120.0188 (11)0.0220 (12)0.0135 (11)0.0092 (9)0.0049 (9)0.0087 (9)
C130.0189 (11)0.0192 (11)0.0135 (11)0.0076 (9)0.0025 (9)0.0078 (9)
C140.0213 (12)0.0230 (12)0.0188 (12)0.0106 (10)0.0072 (10)0.0089 (10)
C150.0213 (12)0.0297 (13)0.0280 (14)0.0111 (10)0.0108 (11)0.0150 (11)
C160.0218 (12)0.0206 (12)0.0317 (14)0.0051 (10)0.0068 (11)0.0140 (11)
C170.0242 (12)0.0183 (12)0.0226 (13)0.0100 (10)0.0047 (10)0.0080 (10)
C180.0217 (11)0.0205 (12)0.0132 (11)0.0091 (10)0.0025 (10)0.0058 (9)
C190.0199 (11)0.0214 (12)0.0168 (12)0.0104 (10)0.0070 (10)0.0059 (10)
C200.0274 (13)0.0214 (12)0.0229 (13)0.0079 (10)0.0087 (11)0.0033 (10)
C210.0269 (13)0.0189 (12)0.0267 (14)0.0034 (10)0.0066 (11)0.0065 (11)
C220.0232 (12)0.0266 (13)0.0326 (14)0.0061 (10)0.0116 (11)0.0149 (11)
N10.0201 (9)0.0137 (9)0.0188 (10)0.0031 (8)0.0067 (8)0.0052 (8)
N20.0183 (9)0.0185 (10)0.0170 (10)0.0077 (8)0.0077 (8)0.0057 (8)
O10.0297 (9)0.0186 (8)0.0307 (10)0.0066 (7)0.0153 (8)0.0035 (7)
O20.0251 (8)0.0186 (8)0.0218 (9)0.0048 (7)0.0122 (7)0.0051 (7)
O30.0283 (9)0.0227 (8)0.0306 (10)0.0107 (7)0.0162 (8)0.0068 (7)
O40.0237 (8)0.0202 (8)0.0244 (9)0.0080 (7)0.0113 (7)0.0073 (7)
S10.0238 (3)0.0201 (3)0.0221 (3)0.0114 (2)0.0109 (3)0.0080 (2)
S20.0248 (3)0.0218 (3)0.0155 (3)0.0092 (2)0.0085 (2)0.0063 (2)
Geometric parameters (Å, °) top
C1—C21.392 (3)C12—S21.7871 (19)
C1—C61.403 (3)C13—C141.392 (3)
C1—S11.777 (2)C13—N21.402 (2)
C2—C31.383 (3)C14—C151.380 (3)
C2—H20.9500C14—H140.9500
C3—C41.378 (3)C15—C161.380 (3)
C3—H30.9500C15—H150.9500
C4—C51.380 (3)C16—C171.382 (3)
C4—H40.9500C16—H160.9500
C5—C61.393 (3)C17—H170.9500
C5—H50.9500C18—O31.224 (2)
C6—N11.403 (2)C18—N21.366 (2)
C7—O11.224 (2)C18—C191.469 (3)
C7—N11.368 (2)C19—C201.344 (3)
C7—C81.468 (3)C19—O41.369 (2)
C8—C91.343 (3)C20—C211.415 (3)
C8—O21.380 (2)C20—H200.9500
C9—C101.415 (3)C21—C221.340 (3)
C9—H90.9500C21—H210.9500
C10—C111.341 (3)C22—O41.366 (2)
C10—H100.9500C22—H220.9500
C11—O21.367 (2)N1—H10.8800
C11—H110.9500N2—H2A0.8800
C12—C171.382 (3)S1—S22.0768 (8)
C12—C131.407 (3)
C2—C1—C6120.24 (19)N2—C13—C12119.02 (17)
C2—C1—S1119.34 (17)C15—C14—C13120.27 (19)
C6—C1—S1120.42 (15)C15—C14—H14119.9
C3—C2—C1119.9 (2)C13—C14—H14119.9
C3—C2—H2120.0C14—C15—C16121.12 (19)
C1—C2—H2120.0C14—C15—H15119.4
C4—C3—C2119.50 (19)C16—C15—H15119.4
C4—C3—H3120.2C15—C16—C17119.2 (2)
C2—C3—H3120.2C15—C16—H16120.4
C3—C4—C5121.6 (2)C17—C16—H16120.4
C3—C4—H4119.2C12—C17—C16120.5 (2)
C5—C4—H4119.2C12—C17—H17119.7
C4—C5—C6119.6 (2)C16—C17—H17119.7
C4—C5—H5120.2O3—C18—N2125.09 (19)
C6—C5—H5120.2O3—C18—C19120.47 (18)
C5—C6—N1122.76 (19)N2—C18—C19114.43 (18)
C5—C6—C1119.09 (18)C20—C19—O4110.13 (18)
N1—C6—C1118.14 (18)C20—C19—C18131.36 (19)
O1—C7—N1124.76 (19)O4—C19—C18118.50 (17)
O1—C7—C8121.70 (19)C19—C20—C21106.93 (19)
N1—C7—C8113.54 (18)C19—C20—H20126.5
C9—C8—O2110.26 (18)C21—C20—H20126.5
C9—C8—C7132.45 (19)C22—C21—C20106.23 (19)
O2—C8—C7117.28 (17)C22—C21—H21126.9
C8—C9—C10106.59 (18)C20—C21—H21126.9
C8—C9—H9126.7C21—C22—O4110.92 (18)
C10—C9—H9126.7C21—C22—H22124.5
C11—C10—C9106.89 (18)O4—C22—H22124.5
C11—C10—H10126.6C7—N1—C6129.57 (17)
C9—C10—H10126.6C7—N1—H1115.2
C10—C11—O2110.59 (18)C6—N1—H1115.2
C10—C11—H11124.7C18—N2—C13129.03 (17)
O2—C11—H11124.7C18—N2—H2A115.5
C17—C12—C13120.33 (18)C13—N2—H2A115.5
C17—C12—S2119.14 (15)C11—O2—C8105.66 (16)
C13—C12—S2120.49 (15)C22—O4—C19105.80 (15)
C14—C13—N2122.53 (18)C1—S1—S2103.80 (7)
C14—C13—C12118.45 (19)C12—S2—S1104.78 (7)
C6—C1—C2—C30.5 (3)C15—C16—C17—C12−0.8 (3)
S1—C1—C2—C3−179.76 (15)O3—C18—C19—C20−5.0 (4)
C1—C2—C3—C42.2 (3)N2—C18—C19—C20175.9 (2)
C2—C3—C4—C5−2.5 (3)O3—C18—C19—O4176.19 (18)
C3—C4—C5—C60.1 (3)N2—C18—C19—O4−2.9 (3)
C4—C5—C6—N1−176.52 (18)O4—C19—C20—C210.4 (3)
C4—C5—C6—C12.6 (3)C18—C19—C20—C21−178.5 (2)
C2—C1—C6—C5−2.9 (3)C19—C20—C21—C22−0.4 (3)
S1—C1—C6—C5177.37 (15)C20—C21—C22—O40.2 (3)
C2—C1—C6—N1176.30 (17)O1—C7—N1—C6−0.5 (3)
S1—C1—C6—N1−3.5 (2)C8—C7—N1—C6179.00 (18)
O1—C7—C8—C9−6.0 (4)C5—C6—N1—C7−11.6 (3)
N1—C7—C8—C9174.5 (2)C1—C6—N1—C7169.31 (19)
O1—C7—C8—O2172.76 (18)O3—C18—N2—C132.0 (3)
N1—C7—C8—O2−6.8 (3)C19—C18—N2—C13−178.95 (18)
O2—C8—C9—C10−0.6 (2)C14—C13—N2—C183.7 (3)
C7—C8—C9—C10178.2 (2)C12—C13—N2—C18−176.88 (19)
C8—C9—C10—C110.0 (2)C10—C11—O2—C8−1.0 (2)
C9—C10—C11—O20.6 (3)C9—C8—O2—C111.0 (2)
C17—C12—C13—C14−1.6 (3)C7—C8—O2—C11−178.06 (18)
S2—C12—C13—C14−179.28 (15)C21—C22—O4—C190.0 (2)
C17—C12—C13—N2178.93 (18)C20—C19—O4—C22−0.3 (2)
S2—C12—C13—N21.2 (3)C18—C19—O4—C22178.75 (18)
N2—C13—C14—C15178.88 (19)C2—C1—S1—S290.48 (16)
C12—C13—C14—C15−0.6 (3)C6—C1—S1—S2−89.74 (16)
C13—C14—C15—C162.1 (3)C17—C12—S2—S188.52 (16)
C14—C15—C16—C17−1.4 (3)C13—C12—S2—S1−93.76 (16)
C13—C12—C17—C162.3 (3)C1—S1—S2—C1284.72 (10)
S2—C12—C17—C16−179.97 (16)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N2—H2A···S20.882.523.0104 (16)116
N2—H2A···O40.882.242.688 (2)111
N1—H1···S10.882.502.9805 (18)115
N1—H1···O20.882.192.651 (2)112
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N2—H2A···S20.882.523.0104 (16)116
N2—H2A···O40.882.242.688 (2)111
N1—H1···S10.882.502.9805 (18)115
N1—H1···O20.882.192.651 (2)112
references
References top

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