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Acta Cryst. (2011). E67, o1202-o1203    [ doi:10.1107/S1600536811014577 ]

2-[2-(Benzylsulfanyl)phenyl]-1,1,3,3-tetramethylguanidine

A. Neuba, U. Flörke and G. Henkel

Abstract top

The molecular structure of the title compound, C18H23N3S, shows it to be a derivative of an aminothiophenol possessing a tetramethylguanidine group with a localized C=N double bond of 1.304 (2) Å and a protected thiol functional group as an S-benzyl thioether. The two aromatic ring planes make a dihedral angle of 67.69 (6)°.

Comment top

The synthesis and characterization of novel molecules containing nitrogen and sulfur as donor functions and their application in synthesis of sulfur copper complexes is important for biomimetic copper–sulfur chemistry. In search of multifunctional ligands we have extended our studies to guanidyl-type systems with N-donor functions. The first derivative, the ligand bis(tetramethyl-guanidino)propylene as well as amine guanidine hybrids and their complexes with Cu, Fe, Ni, Ag, Mn, Co and Zn have recently been investigated (Harmjanz, 1997; Waden, 1999; Pohl et al., 2000; Schneider, 2000; Wittmann, 1999; Wittmann et al., 2001; Herres-Pawlis et al., 2005, 2009; Herres et al., 2005; Neuba et al., 2008a,b; 2010; Börner et al. 2007, 2009). We have now developed several sulfur guanidine hybrids based on aminothiophenol and cysteamine (Neuba et al., 2007a,b,c; Neuba, 2009). The synthesized sulfur guanidine compounds possess aliphatic and aromatic thioethers or disulfide groups and were used in the synthesis of copper thiolate complexes to mimic active centres like the CuA in cytochrome-c oxidase and N2O-reductase (Neuba et al., 2011). The two aromatic ring planes make a dihedral angle of 67.69 (6)° and the N1—C6—C11—S1—C12—C13 moiety is mostly planar with largest deviation of 0.084 (1) Å for S1 from the best plane. The guanidine plane C1N3 makes an angle of 59.80 (5)° with the attached aromatic ring. The N1═C1 guanidine double bond measures 1.304 (2) Å and is clearly localized. Similar double-bond localization is observed in other guanidine compounds (e.g. Herres et al., 2004; Neuba et al., 2007a,b; Raab et al., 2002, 2003; Peters et al., 2008).

Related literature top

For synthesis, see: Neuba (2009); ; Lindoy & Livingstone (1968); Herres-Pawlis et al. (2005). For related structures, see: Neuba et al. (2007a,b,c); Herres et al. (2004); Raab et al. (2003); Peters et al. (2008); Raab et al. (2002). For complexes of metal centres with bis(tetramethyl-guanidino)propylene and amine guanidine hybrids, see: Harmjanz (1997); Waden (1999); Pohl et al. (2000); Schneider (2000); Wittmann (1999); Wittmann et al. (2001); Herres et al. (2005); Herres-Pawlis et al. (2009); Börner et al. (2007, 2009). For sulfur guanidine hybrids based on aminothiophenol and cysteamine, see: Neuba (2009); Neuba et al. (2007a,b,c, 2008a,b, 2010, 2011).

Experimental top

The title compound was prepared as follows: a solution of tetramethylchloroformamidinium chlorid (Herres-Pawlis et al., 2005) (5.13 g, 30 mmol) in dry MeCN was added dropwise to an ice-cooled solution of 2-(benzylthio)aniline (Lindoy & Livingstone, 1968) (6.45 g, 30 mmol) and triethylamine (4.18 ml, 3.03 g, 30 mmol) in dry MeCN. After 3 h under reflux, a solution of NaOH (1.2 g, 30 mmol) in water was added. The solvents and NEt3 were then evaporated under vacuum. In order to deprotonate the mono-hydrochloride, 50 wt% KOH (aqueous, 15 ml) was added and the free base was extracted into the MeCN phase (3 × 80 ml). The organic phase was dried with Na2SO4. After filtration, the solvent was evaporated under reduced pressure. The title compound was obtained as white powder (yield 69%, 6.4 g). Colourless crystals suitable for X-ray diffraction were obtained by slow cooling of a hot saturated MeCN solution.

Spectroscopic analysis: 1H NMR (500 MHz, CDCl3, 25°C, δ, p.p.m.): 2.68 (s, 12H, CH3), 4.10 (s, 2H, CH2), 6.59 (d, 1H, CH), 6.80 (t, 1H, CH), 7.03 (t, 1H, CH), 7.15 (d, 1H, CH), 7.21 (t, 1H, CH), 7.28 (t, 2H, CH), 7.36 (d, 2H, CH); 13C NMR (125 MHz, CDCl3, 25°C, δ, p.p.m.): 37.3 (CH2), 39.5 (CH3), 120.5 (CH), 121.7 (CH), 126.1 (CH), 126.9 (CH), 127.2 (CH), 127.6 (CH), 128.4 (CH), 128.7 (Cquat), 129.1 (CH), 136.6 (Cquat), 137.8 (Cquat), 160.0 (Cgua); IR (KBr, ν, cm-1): 3053 (w), 3030 (w), 3003 (w), 2918 (m), 2848 (m), 2790 (w), 1589 (vs (C═N)), 1558 (s (C═N)), 1500 (m (C═N)), 1460 (m), 1425 (m), 1377 (s), 1279 (w), 1232 (w), 1207 (w), 1144 (m), 1066 (m), 1038 (m), 1020 (s), 914 (w), 850 (w), 806 (vw), 777 (m), 715 (s), 696 (m), 682 (w), 621 (w), 571 (w), 545 (w), 498 (vw), 484 (w), 461 (w), 445 (w). EI–MS (m/z (%)): 313.0 (100) [M+], 280.0 (31), 269.1 (8) [M+ - N(CH3)2], 242.0 (5), 237.0 (10) [M+ - Ph], 222.0 (14) [M+ - CH2Ph], 215.0 (20), 190.0 (12) [M+ - SCH2Ph], 179.0 (76), 148.9 (28), 135.9 (20), 124.0 (9) [SCH2Ph+], 91.0 (76), 72.0 (20).

Refinement top

H atoms were clearly identified in difference syntheses, idealized and refined riding on the C atoms with C—H = 0.95 (aromatic) or 0.98–0.99 Å, and with isotropic displacement parameters Uiso(H) = 1.2Ueq(C) or 1.5Ueq(–CH3 H atoms). All CH3 H atoms were allowed to rotate but not to tip.

Computing details top

Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT (Bruker, 2002); 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 local programs.

Figures top
[Figure 1] Fig. 1. Molecular structure with displacement ellipsoids drawn at the 50% probability level.
2-[2-(Benzylsulfanyl)phenyl]-1,1,3,3-tetramethylguanidine top
Crystal data top
C18H23N3SF(000) = 672
Mr = 313.45Dx = 1.239 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 842 reflections
a = 7.869 (2) Åθ = 2.7–27.7°
b = 26.850 (7) ŵ = 0.19 mm−1
c = 8.314 (2) ÅT = 120 K
β = 106.959 (5)°Block, colourless
V = 1680.2 (8) Å30.42 × 0.33 × 0.29 mm
Z = 4
Data collection top
Bruker SMART APEX
diffractometer		3988 independent reflections
Radiation source: sealed tube2816 reflections with I > 2σ(I)
graphiteRint = 0.066
φ and ω scansθmax = 27.9°, θmin = 1.5°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2004)		h = −10→9
Tmin = 0.923, Tmax = 0.946k = −35→35
14278 measured reflectionsl = −10→10
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)] = 0.041Hydrogen site location: difference Fourier map
wR(F2) = 0.091H-atom parameters constrained
S = 0.92 w = 1/[σ2(Fo2) + (0.0443P)2]
where P = (Fo2 + 2Fc2)/3
3988 reflections(Δ/σ)max = 0.001
203 parametersΔρmax = 0.24 e Å−3
0 restraintsΔρmin = −0.34 e Å−3
Crystal data top
C18H23N3SV = 1680.2 (8) Å3
Mr = 313.45Z = 4
Monoclinic, P21/cMo Kα radiation
a = 7.869 (2) ŵ = 0.19 mm−1
b = 26.850 (7) ÅT = 120 K
c = 8.314 (2) Å0.42 × 0.33 × 0.29 mm
β = 106.959 (5)°
Data collection top
Bruker SMART APEX
diffractometer		3988 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2004)		2816 reflections with I > 2σ(I)
Tmin = 0.923, Tmax = 0.946Rint = 0.066
14278 measured reflectionsθmax = 27.9°
Refinement top
R[F2 > 2σ(F2)] = 0.041H-atom parameters constrained
wR(F2) = 0.091Δρmax = 0.24 e Å−3
S = 0.92Δρmin = −0.34 e Å−3
3988 reflectionsAbsolute structure: ?
203 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
S10.48274 (6)0.392868 (13)0.76377 (5)0.02350 (11)
N10.64141 (18)0.33140 (4)0.56770 (16)0.0214 (3)
N20.93294 (17)0.29594 (4)0.63993 (16)0.0232 (3)
N30.68294 (18)0.24922 (4)0.50838 (17)0.0239 (3)
C10.7516 (2)0.29479 (5)0.57258 (18)0.0203 (3)
C21.0512 (2)0.27118 (7)0.5595 (2)0.0362 (4)
H2A0.98060.25240.46150.054*
H2B1.12940.24830.63950.054*
H2C1.12310.29610.52320.054*
C31.0191 (2)0.33296 (6)0.7646 (2)0.0291 (4)
H3A1.05870.36090.70890.044*
H3B1.12200.31790.84660.044*
H3C0.93490.34500.82250.044*
C40.4983 (2)0.24676 (6)0.4081 (2)0.0311 (4)
H4A0.42230.24450.48250.047*
H4B0.48000.21730.33540.047*
H4C0.46780.27680.33850.047*
C50.7491 (2)0.20329 (5)0.5999 (2)0.0309 (4)
H5A0.87320.20790.66660.046*
H5B0.74140.17600.51960.046*
H5C0.67720.19520.67460.046*
C60.6947 (2)0.38116 (5)0.56372 (19)0.0192 (3)
C70.7988 (2)0.39792 (5)0.4653 (2)0.0233 (3)
H7A0.84700.37440.40520.028*
C80.8338 (2)0.44823 (6)0.4527 (2)0.0252 (4)
H8A0.90420.45890.38380.030*
C90.7656 (2)0.48271 (5)0.5412 (2)0.0236 (3)
H9A0.79050.51710.53430.028*
C100.6610 (2)0.46705 (5)0.63978 (19)0.0220 (3)
H10A0.61530.49080.70090.026*
C110.6223 (2)0.41684 (5)0.65010 (18)0.0192 (3)
C120.4411 (2)0.44748 (5)0.8758 (2)0.0243 (4)
H12A0.55490.46150.94630.029*
H12B0.37970.47330.79470.029*
C130.3272 (2)0.43232 (5)0.98479 (19)0.0210 (3)
C140.4001 (2)0.40508 (6)1.1318 (2)0.0274 (4)
H14A0.52260.39661.16350.033*
C150.2967 (3)0.39029 (6)1.2317 (2)0.0317 (4)
H15A0.34800.37191.33160.038*
C160.1184 (3)0.40237 (6)1.1860 (2)0.0332 (4)
H16A0.04670.39191.25390.040*
C170.0442 (2)0.42969 (6)1.0417 (2)0.0329 (4)
H17A−0.07810.43841.01130.039*
C180.1484 (2)0.44444 (6)0.9414 (2)0.0266 (4)
H18A0.09670.46300.84200.032*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0297 (2)0.01664 (17)0.0296 (2)−0.00079 (16)0.01715 (18)−0.00202 (15)
N10.0224 (7)0.0167 (6)0.0277 (7)−0.0022 (5)0.0116 (6)−0.0044 (5)
N20.0206 (7)0.0215 (6)0.0263 (7)−0.0002 (5)0.0047 (6)−0.0055 (5)
N30.0234 (7)0.0164 (6)0.0296 (7)−0.0001 (5)0.0043 (6)−0.0045 (5)
C10.0237 (9)0.0187 (7)0.0199 (8)−0.0011 (6)0.0089 (7)−0.0020 (6)
C20.0267 (10)0.0419 (10)0.0414 (11)0.0044 (8)0.0121 (9)−0.0069 (8)
C30.0288 (10)0.0255 (8)0.0281 (9)−0.0054 (7)0.0008 (8)−0.0025 (7)
C40.0253 (10)0.0251 (8)0.0400 (10)−0.0031 (7)0.0049 (8)−0.0076 (7)
C50.0350 (10)0.0193 (7)0.0367 (10)0.0001 (7)0.0076 (9)−0.0016 (7)
C60.0175 (8)0.0181 (7)0.0219 (8)−0.0009 (6)0.0058 (7)−0.0018 (6)
C70.0221 (9)0.0230 (8)0.0277 (8)0.0002 (6)0.0119 (7)−0.0037 (6)
C80.0228 (9)0.0273 (8)0.0279 (9)−0.0026 (7)0.0111 (7)0.0035 (7)
C90.0242 (9)0.0168 (7)0.0289 (9)−0.0020 (6)0.0061 (7)0.0020 (6)
C100.0228 (9)0.0173 (7)0.0252 (8)0.0013 (6)0.0059 (7)−0.0012 (6)
C110.0182 (8)0.0195 (7)0.0209 (8)−0.0004 (6)0.0071 (7)−0.0002 (6)
C120.0305 (10)0.0174 (7)0.0280 (9)0.0022 (6)0.0131 (8)−0.0036 (6)
C130.0258 (9)0.0169 (7)0.0218 (8)0.0007 (6)0.0092 (7)−0.0061 (6)
C140.0259 (9)0.0296 (8)0.0267 (9)0.0056 (7)0.0076 (8)−0.0013 (7)
C150.0425 (11)0.0296 (8)0.0243 (9)0.0015 (8)0.0117 (8)0.0015 (7)
C160.0423 (12)0.0292 (9)0.0372 (10)−0.0078 (8)0.0260 (9)−0.0093 (7)
C170.0224 (10)0.0332 (9)0.0451 (11)0.0010 (7)0.0129 (9)−0.0113 (8)
C180.0282 (10)0.0235 (8)0.0281 (9)0.0028 (7)0.0082 (8)−0.0025 (6)
Geometric parameters (Å, °) top
S1—C111.7661 (15)C6—C111.413 (2)
S1—C121.8175 (15)C7—C81.389 (2)
N1—C11.3035 (19)C7—H7A0.9500
N1—C61.4033 (18)C8—C91.384 (2)
N2—C11.373 (2)C8—H8A0.9500
N2—C31.4536 (19)C9—C101.386 (2)
N2—C21.455 (2)C9—H9A0.9500
N3—C11.3804 (18)C10—C111.390 (2)
N3—C41.451 (2)C10—H10A0.9500
N3—C51.4628 (19)C12—C131.505 (2)
C2—H2A0.9800C12—H12A0.9900
C2—H2B0.9800C12—H12B0.9900
C2—H2C0.9800C13—C181.385 (2)
C3—H3A0.9800C13—C141.396 (2)
C3—H3B0.9800C14—C151.380 (2)
C3—H3C0.9800C14—H14A0.9500
C4—H4A0.9800C15—C161.381 (3)
C4—H4B0.9800C15—H15A0.9500
C4—H4C0.9800C16—C171.382 (2)
C5—H5A0.9800C16—H16A0.9500
C5—H5B0.9800C17—C181.387 (2)
C5—H5C0.9800C17—H17A0.9500
C6—C71.391 (2)C18—H18A0.9500
C11—S1—C12102.33 (7)C8—C7—H7A119.2
C1—N1—C6121.20 (13)C6—C7—H7A119.2
C1—N2—C3121.30 (13)C9—C8—C7119.62 (14)
C1—N2—C2122.01 (13)C9—C8—H8A120.2
C3—N2—C2114.35 (14)C7—C8—H8A120.2
C1—N3—C4118.43 (13)C8—C9—C10120.05 (14)
C1—N3—C5120.43 (14)C8—C9—H9A120.0
C4—N3—C5113.92 (13)C10—C9—H9A120.0
N1—C1—N2126.77 (14)C9—C10—C11120.61 (14)
N1—C1—N3118.33 (15)C9—C10—H10A119.7
N2—C1—N3114.87 (13)C11—C10—H10A119.7
N2—C2—H2A109.5C10—C11—C6119.88 (14)
N2—C2—H2B109.5C10—C11—S1124.60 (12)
H2A—C2—H2B109.5C6—C11—S1115.51 (11)
N2—C2—H2C109.5C13—C12—S1108.58 (10)
H2A—C2—H2C109.5C13—C12—H12A110.0
H2B—C2—H2C109.5S1—C12—H12A110.0
N2—C3—H3A109.5C13—C12—H12B110.0
N2—C3—H3B109.5S1—C12—H12B110.0
H3A—C3—H3B109.5H12A—C12—H12B108.4
N2—C3—H3C109.5C18—C13—C14118.55 (15)
H3A—C3—H3C109.5C18—C13—C12121.19 (14)
H3B—C3—H3C109.5C14—C13—C12120.25 (15)
N3—C4—H4A109.5C15—C14—C13120.91 (16)
N3—C4—H4B109.5C15—C14—H14A119.5
H4A—C4—H4B109.5C13—C14—H14A119.5
N3—C4—H4C109.5C14—C15—C16119.81 (16)
H4A—C4—H4C109.5C14—C15—H15A120.1
H4B—C4—H4C109.5C16—C15—H15A120.1
N3—C5—H5A109.5C15—C16—C17120.10 (16)
N3—C5—H5B109.5C15—C16—H16A120.0
H5A—C5—H5B109.5C17—C16—H16A120.0
N3—C5—H5C109.5C16—C17—C18119.97 (17)
H5A—C5—H5C109.5C16—C17—H17A120.0
H5B—C5—H5C109.5C18—C17—H17A120.0
C7—C6—N1123.59 (13)C13—C18—C17120.66 (16)
C7—C6—C11118.26 (13)C13—C18—H18A119.7
N1—C6—C11117.77 (13)C17—C18—H18A119.7
C8—C7—C6121.54 (14)
C6—N1—C1—N228.2 (2)C9—C10—C11—S1−177.01 (12)
C6—N1—C1—N3−153.64 (14)C7—C6—C11—C10−2.2 (2)
C3—N2—C1—N121.5 (2)N1—C6—C11—C10−175.37 (14)
C2—N2—C1—N1−140.14 (17)C7—C6—C11—S1176.95 (12)
C3—N2—C1—N3−156.70 (13)N1—C6—C11—S13.76 (18)
C2—N2—C1—N341.6 (2)C12—S1—C11—C10−7.87 (16)
C4—N3—C1—N112.7 (2)C12—S1—C11—C6173.05 (12)
C5—N3—C1—N1−135.83 (16)C11—S1—C12—C13−178.03 (11)
C4—N3—C1—N2−168.95 (14)S1—C12—C13—C18−105.18 (15)
C5—N3—C1—N242.6 (2)S1—C12—C13—C1474.12 (16)
C1—N1—C6—C742.6 (2)C18—C13—C14—C150.3 (2)
C1—N1—C6—C11−144.63 (15)C12—C13—C14—C15−179.05 (14)
N1—C6—C7—C8173.60 (15)C13—C14—C15—C160.2 (2)
C11—C6—C7—C80.8 (2)C14—C15—C16—C17−0.8 (2)
C6—C7—C8—C90.7 (2)C15—C16—C17—C180.9 (2)
C7—C8—C9—C10−0.9 (2)C14—C13—C18—C17−0.2 (2)
C8—C9—C10—C11−0.5 (2)C12—C13—C18—C17179.14 (14)
C9—C10—C11—C62.0 (2)C16—C17—C18—C13−0.4 (2)
Acknowledgements top

The authors thank the German Research Council (DFG) and the Federal Ministry of Education and Research (BMBF) for continuous support of their work. AN thanks the university of Paderborn for granting a doctorate scholarship.

references
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