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Acta Crystallogr Sect E Struct Rep Online. 2010 December 1; 66(Pt 12): o3343.
Published online 2010 November 27. doi:  10.1107/S1600536810049159
PMCID: PMC3011471

N-[(1S,2S)-2-Amino-1,2-diphenyl­eth­yl]-4-methyl­benzene­sulfonamide [(S,S)-TsDPEN]

Abstract

The crystal structure of the title compound, C21H22N2O2S, shows a network of N—H(...)N and N—H(...)O hydrogen bonds. The tolyl and 1-phenyl rings are almost mutually coplanar [7.89 (9)°], while the 2-phenyl ring makes a dihedral angle of 50.8 (1) ° with the 1-phenyl ring. An intra­molecular N—H(...)N hydrogen bond stabilizes the mol­ecular conformation.

Related literature

For the synthesis of the title compound, see: Vanino (1923 [triangle]); Mistryukov (2002 [triangle]). The title compound was synthesized as a ligand for Ru-catalyzed asymmetric transfer hydrogenations. Similar to BINAP introduced by the same author, the synthesized diamine permits highly enanti­oselective asymmetric hydrogenation reactions, see: Noyori (1996 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-o3343-scheme1.jpg

Experimental

Crystal data

  • C21H22N2O2S
  • M r = 366.47
  • Orthorhombic, An external file that holds a picture, illustration, etc.
Object name is e-66-o3343-efi1.jpg
  • a = 6.3892 (6) Å
  • b = 12.2290 (11) Å
  • c = 24.281 (2) Å
  • V = 1897.2 (3) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.19 mm−1
  • T = 173 K
  • 0.50 × 0.05 × 0.05 mm

Data collection

  • Bruker APEXII CCD diffractometer
  • 37668 measured reflections
  • 4511 independent reflections
  • 3865 reflections with I > 2σ(I)
  • R int = 0.062

Refinement

  • R[F 2 > 2σ(F 2)] = 0.036
  • wR(F 2) = 0.086
  • S = 1.02
  • 4511 reflections
  • 236 parameters
  • H-atom parameters constrained
  • Δρmax = 0.30 e Å−3
  • Δρmin = −0.30 e Å−3
  • Absolute structure: Flack (1983 [triangle]), 1905 Friedel pairs
  • Flack parameter: 0.01 (7)

Data collection: APEX2 (Bruker, 2006 [triangle]); cell refinement: SAINT (Bruker, 2006 [triangle]); data reduction: SAINT; program(s) used to solve structure: SIR97 (Altomare et al., 1999 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: PLATON (Spek, 2009 [triangle]); software used to prepare material for publication: PLATON.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810049159/bt5420sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810049159/bt5420Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

supplementary crystallographic information

Comment

The title compound is formed from hydrobenzamide in a base catalyzed one-pot reaction involving deprotonation to a diazapentadienide anion, cyclization to amarine, and isomerization at elevated temperature under formation of isoamarine. Subsequent reduction with Al/Hg then furnishes racemic stilbenediamine. To obtain optically pure (S,S)—N-p-toluenesulfonyl-1,2-diphenylethylenediamine, the racemate is converted to the diastereomeric L-tartrate salts which are separated by crystallization. After conversion to the free base, the (S,S)-1,2-diphenylethylenediamine is reacted with p-toluenesulfonyl chloride to give the desired product as colorless crystals. The crystal structure is characterized by a network consisting of the three following hydrogen bonds: N11—H11···N20 (2.09 Å), N20—H20B···O10 (2.17 Å) and N20—H20A···N11 (2.31 Å). The first two bonds build the network to a second molecule while the last one stabilizes the molecular conformation. Furthermore, the aromatic rings C1—C6 and C13—C18 are almost coplanar while the ring C21–26 exhibits a dihedral angle of 50.8 (1) ° to the ring C13—C18. The carbon atoms C12 and C19 are (S)-configurated.

Experimental

The title compound was prepared from hydrobenzamide (Vanino, 1923) as follows: To a suspension of hydrobenzamide (66 g, 0.22 mol) in dry DMSO (100 ml) was added solid NaOH (1.2 g, 0.03 mol) under argon atmosphere and vigorous stirring. After 5 min, the mixture was heated to 323 K and held at this temperature for 1 h. Then, the reaction mixture was heated to 403 K and stirred at that temperature for another 3 h. The mixture was cooled down to 353 K and diluted with ethanol and ammonia (28% in water). For completion of the crystallization, the mixture was allowed to stand at room temperature for 20 h. The crystalline isoamarine was filtered off and washed with 2-propanol (Mistryukov, 2002). Yield: 57.2 g (87%, Lit.:90%), m.p.: 474 K (Lit.: 471–473 K). In an argon atmosphere a mixture of isoamarine (50 g, 0.17 mol), pieces of aluminium foil (13.5 g, 0.5 mol), and HgCl2 (3 g, 0.011 mol) were suspended in dry THF (300 ml). The suspension was stirred for 15 min. Then, water (9 ml) in THF (25 ml) was added during 1.5 h. After 2 h, another portion of water (25 ml) was added and the mixture was allowed to stand for 20 h. A concentrated solution of aqueous ammonia (50 ml) was added and the mixture was set aside for another 24 h before it was filtered. The filtrate was concentrated and the distillate was used to wash the residue on the filter. The obtained filtrate was also concentrated and combined with the remainder obtained in the first evaporation. The resulting oil was dissolved in a mixture of methanol (150 ml), concentrated HCl (75 ml) and water (50 ml). The crystaline dihydrochloride was filtered off, washed with dioxane and dried. To obtain the free base, the salt was dissolved in water (100 ml), NaOH was added and the solution was extracted four times with CHCl3. The combined organic layers were concentrated to dryness (see Mistryukov (2002)). Yield: 19.0 g (53%, Lit.: 78%), m.p.: 354 K (Lit.: 355 K). The obtained diamine (14.5 g, 0.068 mol) was dissolved in ethanol (77 ml) and warmed to 343 K. To this solution, L-(+)-tartaric acid (10.2 g, 0.068 mol) dissolved in hot (343 K) ethanol (77 ml) was added. The mixture was allowed to cool to ambient temperature before filtration. The crystals were washed with ethanol and dried in vacuo. The salt was then dissolved in boiling water (77 ml), ethanol (77 ml) was added and the mixture was allowed to cool slowly to room temperature. This procedure was repeated twice to give the desired (S,S)-diamine-(R,R)-tartrate salt. Yield: 6.0 g (48%, Lit.: 63–69%), m.p.: 465 K, [α]D23: -10.4° (H2O, c=1.0), Lit.: -10.8° (H2O, c=1.3). The salt was suspended in water (80 ml), cooled to 273 K and 8 ml of 50% aqueous solution of NaOH were added dropwise. The solution was extracted with CH2Cl2, the combined organic layers were washed with brine and dried over anhydrous Na2SO4. The solvent was evaporated in vacuo. From the combined filtrates and mother liquors, the (R,R)-diamine can be obtained in a similar fashion by crystallization with D-(–)-tartaric acid. Yield: 3.2 g (44%, Lit.: 57–66%), m.p.: 356 K, Lit.: 356 K, [α]D23: -101.9° (MeOH, c=1.0), Lit.: -106.0° (MeOH, c=1.1). For the tosylation, (S,S)-1,2-diphenylethylenediamine (0.3 g, 1.41 mmol) was dissolved in dry CH2Cl2 (3 ml) and Et3N (320 µL) was added. Then, p-toluenesulfonyl chloride (0.256 g, 1.41 mmol) dissolved in dry CH2Cl2 (9 mL) was added dropwise. After 30 min of stirring, the solution was diluted with CH2Cl2 to twice its volume and washed with saturated NaHCO3, brine and dried over anhydrous Na2SO4. After evaporation of the solvent, the product was purified by flash chromatography on silica (petroleum ether/ethyl acetate, 2:3) and subsequently recrystallized from benzene. Yield: 0.33 g (62%, Lit.: 49%), m.p.: 403 K, [α]D23: -90° (MeOH, c=1.0), Lit.: -89° (MeOH, c=1.0).

Refinement

Hydrogen atoms attached to carbons were placed at calculated positions with C—H = 0.95 Å (aromatic) or 0.98–0.99 Å (sp3 C-atom). Hydrogen atoms attached to nitrogen were located in difference Fourier maps. All H atoms were refined in the riding-model approximation with isotropic displacement parameters (set at 1.2–1.5 times of the Ueq of the parent atom).

Figures

Fig. 1.
View of compound I. Displacement ellipsoids are drawn at the 50% probability level.
Fig. 2.
Part of the packing of I showing the hydrogen bond network. View along b axis.

Crystal data

C21H22N2O2SDx = 1.283 Mg m3
Mr = 366.47Melting point: 403 K
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 6316 reflections
a = 6.3892 (6) Åθ = 2.3–26.7°
b = 12.2290 (11) ŵ = 0.19 mm1
c = 24.281 (2) ÅT = 173 K
V = 1897.2 (3) Å3Needle, colourless
Z = 40.50 × 0.05 × 0.05 mm
F(000) = 776

Data collection

Bruker APEXII CCD diffractometer3865 reflections with I > 2σ(I)
Radiation source: sealed TubeRint = 0.062
graphiteθmax = 27.9°, θmin = 1.9°
CCD scanh = −8→8
37668 measured reflectionsk = −16→16
4511 independent reflectionsl = −31→31

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.036H-atom parameters constrained
wR(F2) = 0.086w = 1/[σ2(Fo2) + (0.0404P)2 + 0.3917P] where P = (Fo2 + 2Fc2)/3
S = 1.02(Δ/σ)max < 0.001
4511 reflectionsΔρmax = 0.30 e Å3
236 parametersΔρmin = −0.30 e Å3
0 restraintsAbsolute structure: Flack (1983), 1905 Friedel pairs
Primary atom site location: structure-invariant direct methodsFlack parameter: 0.01 (7)

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 (Å2)

xyzUiso*/Ueq
C10.5561 (3)0.73082 (14)0.30984 (7)0.0254 (4)
C20.4667 (3)0.64651 (15)0.27929 (7)0.0279 (4)
H20.32710.62370.28630.033*
C30.5848 (3)0.59602 (15)0.23830 (7)0.0306 (4)
H30.52340.53990.21660.037*
C40.7904 (3)0.62644 (18)0.22876 (7)0.0329 (5)
C50.8743 (3)0.71278 (18)0.25899 (7)0.0335 (4)
H51.01340.73610.25160.040*
C60.7597 (3)0.76556 (16)0.29955 (7)0.0296 (4)
H60.81890.82420.31990.036*
C70.9227 (4)0.5637 (2)0.18787 (9)0.0502 (6)
H7A0.95530.49130.20290.075*
H7B1.05300.60370.18100.075*
H7C0.84540.55550.15330.075*
S80.42061 (7)0.78898 (4)0.366248 (17)0.02678 (11)
O90.4722 (2)0.90309 (10)0.36804 (5)0.0385 (4)
O100.2061 (2)0.75474 (12)0.36209 (5)0.0361 (3)
N110.5121 (2)0.73717 (11)0.42319 (6)0.0236 (3)
H110.64530.76830.43440.028*
C120.4568 (3)0.62583 (14)0.44193 (7)0.0223 (4)
H120.30070.62140.44340.027*
C130.5326 (3)0.53456 (15)0.40392 (7)0.0247 (4)
C140.3947 (4)0.45222 (16)0.38829 (8)0.0366 (5)
H140.25640.45180.40260.044*
C150.4569 (4)0.37034 (18)0.35183 (9)0.0466 (6)
H150.36140.31440.34150.056*
C160.6570 (4)0.37089 (19)0.33092 (9)0.0466 (6)
H160.69930.31590.30560.056*
C170.7967 (4)0.45140 (18)0.34668 (8)0.0393 (5)
H170.93510.45120.33240.047*
C180.7356 (3)0.53278 (15)0.38341 (7)0.0291 (4)
H180.83300.58720.39450.035*
C190.5390 (3)0.61293 (14)0.50177 (7)0.0226 (4)
H190.69440.62240.50150.027*
N200.4464 (2)0.70033 (12)0.53631 (6)0.0268 (3)
H20A0.50380.76580.51740.032*
H20B0.51000.70340.56790.032*
C210.4890 (3)0.50046 (15)0.52464 (7)0.0257 (4)
C220.2902 (3)0.47483 (17)0.54406 (8)0.0328 (4)
H220.18330.52880.54400.039*
C230.2476 (4)0.36990 (19)0.56357 (9)0.0434 (5)
H230.11180.35280.57700.052*
C240.4014 (4)0.29086 (18)0.56347 (9)0.0469 (6)
H240.37060.21930.57630.056*
C250.5992 (4)0.31529 (17)0.54489 (9)0.0456 (6)
H250.70540.26090.54510.055*
C260.6430 (3)0.41983 (16)0.52574 (8)0.0343 (5)
H260.78010.43660.51320.041*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C10.0288 (10)0.0289 (9)0.0185 (7)0.0034 (8)−0.0029 (7)0.0021 (7)
C20.0279 (10)0.0324 (10)0.0232 (8)−0.0010 (8)−0.0036 (7)0.0037 (7)
C30.0362 (11)0.0336 (10)0.0219 (8)0.0003 (10)−0.0040 (8)−0.0023 (7)
C40.0356 (12)0.0424 (12)0.0208 (9)0.0060 (10)0.0021 (8)0.0058 (8)
C50.0282 (11)0.0455 (11)0.0268 (9)−0.0045 (10)0.0025 (7)0.0062 (9)
C60.0316 (10)0.0318 (11)0.0253 (9)−0.0034 (8)−0.0040 (8)0.0013 (7)
C70.0485 (14)0.0662 (16)0.0360 (11)0.0062 (13)0.0115 (11)−0.0073 (11)
S80.0311 (2)0.0291 (2)0.02014 (19)0.0075 (2)−0.00348 (19)0.00053 (18)
O90.0594 (10)0.0284 (7)0.0276 (6)0.0100 (6)−0.0056 (7)0.0018 (6)
O100.0263 (7)0.0561 (9)0.0258 (6)0.0114 (6)−0.0016 (6)−0.0028 (6)
N110.0281 (8)0.0228 (7)0.0197 (7)0.0006 (6)−0.0035 (6)0.0000 (6)
C120.0243 (9)0.0228 (8)0.0199 (7)0.0010 (7)−0.0007 (7)−0.0009 (6)
C130.0314 (11)0.0234 (9)0.0193 (8)0.0027 (8)−0.0039 (7)0.0007 (7)
C140.0457 (13)0.0328 (10)0.0314 (10)−0.0052 (10)−0.0062 (9)−0.0017 (8)
C150.0673 (17)0.0312 (11)0.0413 (12)−0.0040 (11)−0.0149 (11)−0.0086 (9)
C160.0717 (18)0.0353 (12)0.0328 (11)0.0188 (12)−0.0079 (11)−0.0115 (9)
C170.0473 (14)0.0425 (13)0.0281 (9)0.0182 (10)−0.0010 (10)0.0016 (9)
C180.0349 (11)0.0278 (10)0.0245 (8)0.0061 (9)−0.0038 (8)0.0017 (8)
C190.0212 (9)0.0245 (8)0.0220 (8)−0.0002 (7)−0.0007 (7)0.0004 (7)
N200.0325 (9)0.0267 (7)0.0213 (6)−0.0012 (7)−0.0019 (6)−0.0015 (6)
C210.0321 (10)0.0267 (9)0.0184 (8)−0.0019 (8)−0.0022 (7)−0.0002 (7)
C220.0351 (12)0.0326 (11)0.0306 (10)−0.0030 (9)−0.0016 (9)0.0002 (8)
C230.0522 (14)0.0400 (13)0.0379 (11)−0.0142 (12)0.0048 (10)0.0047 (10)
C240.0753 (17)0.0275 (10)0.0380 (11)−0.0099 (13)0.0001 (11)0.0067 (9)
C250.0679 (17)0.0308 (11)0.0380 (11)0.0121 (11)0.0027 (11)0.0069 (9)
C260.0389 (12)0.0322 (10)0.0318 (10)0.0053 (9)0.0032 (8)0.0039 (9)

Geometric parameters (Å, °)

C1—C61.391 (3)C14—C151.394 (3)
C1—C21.393 (2)C14—H140.9500
C1—S81.7694 (18)C15—C161.376 (4)
C2—C31.393 (3)C15—H150.9500
C2—H20.9500C16—C171.383 (3)
C3—C41.385 (3)C16—H160.9500
C3—H30.9500C17—C181.392 (3)
C4—C51.393 (3)C17—H170.9500
C4—C71.512 (3)C18—H180.9500
C5—C61.387 (3)C19—N201.482 (2)
C5—H50.9500C19—C211.517 (2)
C6—H60.9500C19—H191.0000
C7—H7A0.9800N20—H20A0.9933
C7—H7B0.9800N20—H20B0.8686
C7—H7C0.9800C21—C221.391 (3)
S8—O91.4345 (14)C21—C261.393 (3)
S8—O101.4367 (14)C22—C231.395 (3)
S8—N111.6294 (14)C22—H220.9500
N11—C121.478 (2)C23—C241.378 (3)
N11—H110.9714C23—H230.9500
C12—C131.527 (2)C24—C251.375 (4)
C12—C191.553 (2)C24—H240.9500
C12—H121.0000C25—C261.389 (3)
C13—C181.390 (3)C25—H250.9500
C13—C141.391 (3)C26—H260.9500
C6—C1—C2120.92 (17)C13—C14—C15120.9 (2)
C6—C1—S8118.28 (14)C13—C14—H14119.6
C2—C1—S8120.62 (15)C15—C14—H14119.6
C1—C2—C3119.12 (18)C16—C15—C14119.7 (2)
C1—C2—H2120.4C16—C15—H15120.2
C3—C2—H2120.4C14—C15—H15120.2
C4—C3—C2120.95 (19)C15—C16—C17120.1 (2)
C4—C3—H3119.5C15—C16—H16120.0
C2—C3—H3119.5C17—C16—H16120.0
C3—C4—C5118.72 (18)C16—C17—C18120.3 (2)
C3—C4—C7120.2 (2)C16—C17—H17119.8
C5—C4—C7121.0 (2)C18—C17—H17119.8
C6—C5—C4121.56 (18)C13—C18—C17120.2 (2)
C6—C5—H5119.2C13—C18—H18119.9
C4—C5—H5119.2C17—C18—H18119.9
C5—C6—C1118.66 (18)N20—C19—C21111.26 (14)
C5—C6—H6120.7N20—C19—C12108.75 (13)
C1—C6—H6120.7C21—C19—C12111.30 (14)
C4—C7—H7A109.5N20—C19—H19108.5
C4—C7—H7B109.5C21—C19—H19108.5
H7A—C7—H7B109.5C12—C19—H19108.5
C4—C7—H7C109.5C19—N20—H20A99.9
H7A—C7—H7C109.5C19—N20—H20B110.1
H7B—C7—H7C109.5H20A—N20—H20B101.6
O9—S8—O10120.33 (9)C22—C21—C26118.62 (18)
O9—S8—N11105.67 (8)C22—C21—C19121.39 (17)
O10—S8—N11106.77 (8)C26—C21—C19119.99 (17)
O9—S8—C1107.58 (9)C21—C22—C23120.1 (2)
O10—S8—C1107.16 (8)C21—C22—H22120.0
N11—S8—C1108.97 (8)C23—C22—H22120.0
C12—N11—S8122.26 (12)C24—C23—C22120.4 (2)
C12—N11—H11119.0C24—C23—H23119.8
S8—N11—H11113.5C22—C23—H23119.8
N11—C12—C13114.30 (14)C25—C24—C23120.2 (2)
N11—C12—C19107.51 (13)C25—C24—H24119.9
C13—C12—C19112.59 (14)C23—C24—H24119.9
N11—C12—H12107.4C24—C25—C26119.7 (2)
C13—C12—H12107.4C24—C25—H25120.2
C19—C12—H12107.4C26—C25—H25120.2
C18—C13—C14118.82 (18)C25—C26—C21121.0 (2)
C18—C13—C12121.59 (17)C25—C26—H26119.5
C14—C13—C12119.57 (18)C21—C26—H26119.5
C6—C1—C2—C30.7 (3)C18—C13—C14—C15−1.3 (3)
S8—C1—C2—C3−174.34 (14)C12—C13—C14—C15177.33 (18)
C1—C2—C3—C41.8 (3)C13—C14—C15—C16−0.1 (3)
C2—C3—C4—C5−3.4 (3)C14—C15—C16—C171.0 (3)
C2—C3—C4—C7174.21 (19)C15—C16—C17—C18−0.5 (3)
C3—C4—C5—C62.5 (3)C14—C13—C18—C171.8 (3)
C7—C4—C5—C6−175.05 (19)C12—C13—C18—C17−176.82 (16)
C4—C5—C6—C1−0.1 (3)C16—C17—C18—C13−0.9 (3)
C2—C1—C6—C5−1.5 (3)N11—C12—C19—N2057.03 (17)
S8—C1—C6—C5173.62 (14)C13—C12—C19—N20−176.20 (15)
C6—C1—S8—O939.30 (17)N11—C12—C19—C21179.94 (14)
C2—C1—S8—O9−145.58 (14)C13—C12—C19—C21−53.3 (2)
C6—C1—S8—O10170.01 (14)N20—C19—C21—C2242.9 (2)
C2—C1—S8—O10−14.86 (17)C12—C19—C21—C22−78.6 (2)
C6—C1—S8—N11−74.81 (16)N20—C19—C21—C26−138.06 (17)
C2—C1—S8—N11100.31 (15)C12—C19—C21—C26100.49 (19)
O9—S8—N11—C12168.30 (14)C26—C21—C22—C23−0.7 (3)
O10—S8—N11—C1239.08 (15)C19—C21—C22—C23178.40 (18)
C1—S8—N11—C12−76.35 (15)C21—C22—C23—C24−0.3 (3)
S8—N11—C12—C1364.27 (19)C22—C23—C24—C251.0 (3)
S8—N11—C12—C19−169.97 (12)C23—C24—C25—C26−0.5 (3)
N11—C12—C13—C1846.5 (2)C24—C25—C26—C21−0.5 (3)
C19—C12—C13—C18−76.5 (2)C22—C21—C26—C251.1 (3)
N11—C12—C13—C14−132.06 (17)C19—C21—C26—C25−177.99 (18)
C19—C12—C13—C14104.89 (19)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N11—H11···N20i0.972.093.041 (2)167
N20—H20A···N110.992.312.8149 (19)110
N20—H20B···O10i0.872.173.0236 (19)166

Symmetry codes: (i) x+1/2, −y+3/2, −z+1.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BT5420).

References

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