organic compounds
meso-4,5-Diphenylimidazolidin-2-one
aDepartment of Chemistry and Biology, Ryerson University, Toronto, Ontario, Canada M5B 2K3, and bDepartment of Chemistry, University of Toronto, 80 St George St, Toronto, Ontario, Canada M5B 2K3
*Correspondence e-mail: alough@chem.utoronto.ca
The 15H14N2O, confirms the cis relationship between the phenyl groups at the 4- and 5-positions on the imidazolidine ring. The dihedral angle between the two phenyl rings is 48.14 (6)°. In the intermolecular N—H⋯O hydrogen bonds link molecules into centrosymmetric dimers. These dimers are, in turn, linked into a two-dimensional network via weak N—H⋯π(arene) interactions and π–π stacking interactions with centroid–centroid distances of 3.6937 (11) Å.
determination of the title compound, CRelated literature
For the first synthesis of this compound, see: Biniecki & Moll (1974). For the synthesis of the trans-isomers, see: Sankhavasi et al. (1991). For the of the (R,R)-isomer, see: Siegler & Long (2006). For the synthesis of the precursor, see: Proskurnina et al. (2002). For applications of related enantiopure compounds, see: Sankhavasi et al. (1991); Isobe et al. (1998); Lou et al. (2004). For potential applications of the title compound, see: Porosa & Viirre (2009).
Experimental
Crystal data
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Refinement
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Data collection: COLLECT (Nonius, 2002); cell DENZO-SMN (Otwinowski & Minor, 1997); data reduction: DENZO-SMN; program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXTL.
Supporting information
10.1107/S1600536809046133/sj2668sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809046133/sj2668Isup2.hkl
A suspension of 1,2-diamino-N-benzoyl-N'-benzylidene-1,2-diphenylethane (23.0 g, 57 mmol) in a mixture of glacial acetic acid (115 ml) and 48% aqueous HBr (230 ml) was heated to reflux for four days. The mixture was then cooled in an ice bath and diethyl ether (200 ml) was added and vigourous stirring was continued for 30 minutes before being filtered and washed with diethyl ether. The solid filtrate was added to 100 ml of ice-cold 40% aqueous NaOH, which was then extracted three times with CH2Cl2 (150 ml). The organic extracts were evaporated to dryness and recrystallized from water to obtain meso-1,2-diamino-1,2-diphenylethane (7.8 g, 65% yield). 1H NMR [400 MHz, CDCl3] δH 7.41–7.26 (m, 10H), 4.02 (s, 2H), 1.33 (s, 4H). 13C NMR [100 MHz, CDCl3] δC 142.8, 128.3, 127.5, 127.4, 62.7. A portion of this diamine (5.095 g, 24 mmol) was dissolved in CH2Cl2 (50 ml) and cooled in an ice bath, while a solution of 1,1'-carbonyldiimidazole (8.108 g, 50 mmol) in CH2Cl2 (250 ml) was added dropwise. The mixture was stirred for two hours, and the solvent was evaporated under reduced pressure. The solid was taken up in MeOH (200 ml), cooled in an ice bath, 20 ml of 40% aqueous NaOH was added, and the mixture was stirred for 30 minutes. Methanol was evaporated under reduced pressure, and the remaining aqueous solution was cooled in an ice bath and acidified to pH = 1 with 0.5 M HCl, upon which the title compound crystallized. The crystals were filtered to obtain meso-4,5-diphenylimidazolin-2-one (5.560 g, 97% yield). 1H NMR [400 MHz, CDCl3] δH 7.10–7.05 (m, 6H), 6.97–6.93 (m, 4H), 5.17 (s, 2H), 5.01 (broad s, 2H). 13C NMR [100 MHz, CDCl3] δC 163.5, 137.0, 128.0, 127.8, 127.0, 61.8.
H atoms bound to C were placed in calculated positions with C—H distances in the range 0.95–1.00Å and included in the
in a riding-model approximation with Uiso(H) = 1.2Ueq(C). The H atoms bonded to N atoms were refined independently with isotropic displacement parameters.Data collection: COLLECT (Nonius, 2002); cell
DENZO-SMN (Otwinowski & Minor, 1997); data reduction: DENZO-SMN (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).C15H14N2O | Z = 2 |
Mr = 238.28 | F(000) = 252 |
Triclinic, P1 | Dx = 1.327 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 6.3539 (4) Å | Cell parameters from 6535 reflections |
b = 8.6159 (4) Å | θ = 3.0–27.5° |
c = 11.3211 (7) Å | µ = 0.09 mm−1 |
α = 86.147 (3)° | T = 150 K |
β = 76.094 (3)° | Plate, colourless |
γ = 82.718 (3)° | 0.20 × 0.20 × 0.08 mm |
V = 596.32 (6) Å3 |
Nonius KappaCCD diffractometer | 2685 independent reflections |
Radiation source: fine-focus sealed tube | 1771 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.047 |
Detector resolution: 9 pixels mm-1 | θmax = 27.5°, θmin = 3.0° |
ω scans | h = −8→8 |
Absorption correction: multi-scan (SORTAV; Blessing, 1995) | k = −11→11 |
Tmin = 0.873, Tmax = 0.995 | l = −12→14 |
6535 measured reflections |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.054 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.156 | w = 1/[σ2(Fo2) + (0.0787P)2 + 0.1078P] where P = (Fo2 + 2Fc2)/3 |
S = 1.03 | (Δ/σ)max < 0.001 |
2685 reflections | Δρmax = 0.25 e Å−3 |
172 parameters | Δρmin = −0.25 e Å−3 |
0 restraints | Extinction correction: SHELXTL (Version 6.1; Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.043 (9) |
C15H14N2O | γ = 82.718 (3)° |
Mr = 238.28 | V = 596.32 (6) Å3 |
Triclinic, P1 | Z = 2 |
a = 6.3539 (4) Å | Mo Kα radiation |
b = 8.6159 (4) Å | µ = 0.09 mm−1 |
c = 11.3211 (7) Å | T = 150 K |
α = 86.147 (3)° | 0.20 × 0.20 × 0.08 mm |
β = 76.094 (3)° |
Nonius KappaCCD diffractometer | 2685 independent reflections |
Absorption correction: multi-scan (SORTAV; Blessing, 1995) | 1771 reflections with I > 2σ(I) |
Tmin = 0.873, Tmax = 0.995 | Rint = 0.047 |
6535 measured reflections |
R[F2 > 2σ(F2)] = 0.054 | 0 restraints |
wR(F2) = 0.156 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | Δρmax = 0.25 e Å−3 |
2685 reflections | Δρmin = −0.25 e Å−3 |
172 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.5277 (2) | 0.41749 (16) | 0.65182 (13) | 0.0402 (4) | |
N1 | 0.2254 (3) | 0.55213 (18) | 0.59441 (15) | 0.0298 (4) | |
N2 | 0.2105 (3) | 0.50802 (19) | 0.79050 (15) | 0.0310 (4) | |
C1 | 0.0274 (3) | 0.6470 (2) | 0.65473 (17) | 0.0264 (4) | |
H1A | −0.0938 | 0.6328 | 0.6156 | 0.032* | |
C2 | 0.3394 (3) | 0.4852 (2) | 0.67556 (18) | 0.0308 (5) | |
C3 | −0.0134 (3) | 0.5630 (2) | 0.78442 (17) | 0.0283 (5) | |
H3A | −0.0926 | 0.4701 | 0.7831 | 0.034* | |
C4 | 0.0525 (3) | 0.8203 (2) | 0.65330 (16) | 0.0243 (4) | |
C5 | 0.2551 (3) | 0.8742 (2) | 0.63592 (17) | 0.0288 (5) | |
H5A | 0.3829 | 0.8014 | 0.6267 | 0.035* | |
C6 | 0.2724 (3) | 1.0331 (2) | 0.63194 (18) | 0.0315 (5) | |
H6A | 0.4118 | 1.0687 | 0.6195 | 0.038* | |
C7 | 0.0879 (3) | 1.1399 (2) | 0.64589 (18) | 0.0318 (5) | |
H7A | 0.1004 | 1.2489 | 0.6430 | 0.038* | |
C8 | −0.1151 (3) | 1.0882 (2) | 0.66414 (17) | 0.0317 (5) | |
H8A | −0.2426 | 1.1614 | 0.6741 | 0.038* | |
C9 | −0.1316 (3) | 0.9287 (2) | 0.66781 (17) | 0.0278 (5) | |
H9A | −0.2713 | 0.8934 | 0.6805 | 0.033* | |
C10 | −0.1371 (3) | 0.6618 (2) | 0.88918 (16) | 0.0259 (4) | |
C11 | −0.0311 (3) | 0.7520 (2) | 0.94856 (17) | 0.0297 (5) | |
H11A | 0.1228 | 0.7514 | 0.9233 | 0.036* | |
C12 | −0.1480 (3) | 0.8430 (2) | 1.04446 (18) | 0.0338 (5) | |
H12A | −0.0735 | 0.9030 | 1.0852 | 0.041* | |
C13 | −0.3712 (3) | 0.8468 (2) | 1.08089 (18) | 0.0339 (5) | |
H13A | −0.4510 | 0.9103 | 1.1459 | 0.041* | |
C14 | −0.4787 (3) | 0.7580 (2) | 1.02265 (19) | 0.0364 (5) | |
H14A | −0.6328 | 0.7603 | 1.0479 | 0.044* | |
C15 | −0.3626 (3) | 0.6652 (2) | 0.92714 (17) | 0.0307 (5) | |
H15A | −0.4376 | 0.6039 | 0.8878 | 0.037* | |
H2N | 0.248 (3) | 0.441 (3) | 0.846 (2) | 0.035 (6)* | |
H1N | 0.297 (3) | 0.569 (2) | 0.514 (2) | 0.040 (6)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0377 (9) | 0.0356 (8) | 0.0365 (9) | 0.0126 (7) | 0.0019 (7) | 0.0053 (6) |
N1 | 0.0339 (10) | 0.0250 (8) | 0.0261 (9) | 0.0018 (7) | −0.0011 (7) | −0.0002 (7) |
N2 | 0.0309 (10) | 0.0292 (9) | 0.0270 (9) | 0.0048 (7) | −0.0014 (7) | 0.0069 (7) |
C1 | 0.0257 (10) | 0.0249 (9) | 0.0265 (10) | −0.0011 (8) | −0.0025 (8) | −0.0022 (8) |
C2 | 0.0338 (12) | 0.0231 (10) | 0.0314 (11) | 0.0017 (8) | −0.0030 (9) | 0.0025 (8) |
C3 | 0.0265 (10) | 0.0236 (9) | 0.0324 (10) | −0.0035 (8) | −0.0019 (8) | 0.0000 (8) |
C4 | 0.0262 (10) | 0.0269 (10) | 0.0189 (9) | −0.0010 (8) | −0.0048 (7) | 0.0006 (7) |
C5 | 0.0279 (11) | 0.0279 (10) | 0.0299 (10) | −0.0008 (8) | −0.0070 (8) | 0.0013 (8) |
C6 | 0.0328 (11) | 0.0335 (11) | 0.0296 (11) | −0.0088 (9) | −0.0077 (9) | 0.0003 (8) |
C7 | 0.0420 (12) | 0.0253 (10) | 0.0270 (10) | −0.0048 (9) | −0.0056 (9) | −0.0015 (8) |
C8 | 0.0334 (12) | 0.0284 (10) | 0.0292 (11) | 0.0047 (9) | −0.0041 (9) | 0.0001 (8) |
C9 | 0.0245 (10) | 0.0302 (10) | 0.0275 (10) | −0.0021 (8) | −0.0047 (8) | 0.0006 (8) |
C10 | 0.0262 (10) | 0.0227 (9) | 0.0259 (10) | −0.0024 (8) | −0.0026 (8) | 0.0057 (7) |
C11 | 0.0269 (10) | 0.0310 (10) | 0.0296 (10) | −0.0081 (8) | −0.0017 (8) | 0.0013 (8) |
C12 | 0.0444 (13) | 0.0292 (10) | 0.0277 (11) | −0.0119 (9) | −0.0045 (9) | 0.0012 (8) |
C13 | 0.0402 (13) | 0.0303 (11) | 0.0258 (10) | 0.0024 (9) | −0.0009 (9) | 0.0001 (8) |
C14 | 0.0262 (11) | 0.0460 (13) | 0.0326 (11) | 0.0013 (9) | −0.0024 (9) | 0.0032 (10) |
C15 | 0.0288 (11) | 0.0336 (11) | 0.0288 (10) | −0.0052 (8) | −0.0047 (8) | −0.0001 (8) |
O1—C2 | 1.238 (2) | C6—H6A | 0.9500 |
N1—C2 | 1.358 (3) | C7—C8 | 1.382 (3) |
N1—C1 | 1.456 (2) | C7—H7A | 0.9500 |
N1—H1N | 0.93 (2) | C8—C9 | 1.389 (3) |
N2—C2 | 1.373 (3) | C8—H8A | 0.9500 |
N2—C3 | 1.458 (3) | C9—H9A | 0.9500 |
N2—H2N | 0.87 (2) | C10—C11 | 1.389 (3) |
C1—C4 | 1.520 (2) | C10—C15 | 1.391 (3) |
C1—C3 | 1.571 (3) | C11—C12 | 1.387 (3) |
C1—H1A | 1.0000 | C11—H11A | 0.9500 |
C3—C10 | 1.506 (3) | C12—C13 | 1.375 (3) |
C3—H3A | 1.0000 | C12—H12A | 0.9500 |
C4—C9 | 1.386 (3) | C13—C14 | 1.380 (3) |
C4—C5 | 1.389 (3) | C13—H13A | 0.9500 |
C5—C6 | 1.384 (3) | C14—C15 | 1.392 (3) |
C5—H5A | 0.9500 | C14—H14A | 0.9500 |
C6—C7 | 1.379 (3) | C15—H15A | 0.9500 |
C2—N1—C1 | 111.46 (16) | C5—C6—H6A | 119.9 |
C2—N1—H1N | 119.9 (13) | C6—C7—C8 | 119.96 (17) |
C1—N1—H1N | 123.4 (13) | C6—C7—H7A | 120.0 |
C2—N2—C3 | 110.27 (16) | C8—C7—H7A | 120.0 |
C2—N2—H2N | 113.6 (14) | C7—C8—C9 | 119.57 (18) |
C3—N2—H2N | 124.9 (14) | C7—C8—H8A | 120.2 |
N1—C1—C4 | 113.60 (15) | C9—C8—H8A | 120.2 |
N1—C1—C3 | 99.73 (14) | C4—C9—C8 | 121.04 (17) |
C4—C1—C3 | 114.88 (14) | C4—C9—H9A | 119.5 |
N1—C1—H1A | 109.4 | C8—C9—H9A | 119.5 |
C4—C1—H1A | 109.4 | C11—C10—C15 | 118.79 (18) |
C3—C1—H1A | 109.4 | C11—C10—C3 | 121.43 (17) |
O1—C2—N1 | 126.79 (18) | C15—C10—C3 | 119.77 (17) |
O1—C2—N2 | 125.27 (18) | C12—C11—C10 | 120.59 (18) |
N1—C2—N2 | 107.93 (17) | C12—C11—H11A | 119.7 |
N2—C3—C10 | 113.62 (16) | C10—C11—H11A | 119.7 |
N2—C3—C1 | 100.24 (14) | C13—C12—C11 | 120.32 (19) |
C10—C3—C1 | 116.28 (14) | C13—C12—H12A | 119.8 |
N2—C3—H3A | 108.8 | C11—C12—H12A | 119.8 |
C10—C3—H3A | 108.8 | C12—C13—C14 | 119.72 (19) |
C1—C3—H3A | 108.8 | C12—C13—H13A | 120.1 |
C9—C4—C5 | 118.61 (16) | C14—C13—H13A | 120.1 |
C9—C4—C1 | 119.26 (16) | C13—C14—C15 | 120.36 (19) |
C5—C4—C1 | 122.12 (16) | C13—C14—H14A | 119.8 |
C6—C5—C4 | 120.56 (18) | C15—C14—H14A | 119.8 |
C6—C5—H5A | 119.7 | C10—C15—C14 | 120.20 (18) |
C4—C5—H5A | 119.7 | C10—C15—H15A | 119.9 |
C7—C6—C5 | 120.26 (18) | C14—C15—H15A | 119.9 |
C7—C6—H6A | 119.9 |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1N···O1i | 0.93 (2) | 1.94 (2) | 2.864 (2) | 173 (2) |
N2—H2N···Cg1ii | 0.87 (2) | 2.46 (2) | 3.322 (2) | 165 (2) |
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) −x, −y+1, −z+2. |
Experimental details
Crystal data | |
Chemical formula | C15H14N2O |
Mr | 238.28 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 150 |
a, b, c (Å) | 6.3539 (4), 8.6159 (4), 11.3211 (7) |
α, β, γ (°) | 86.147 (3), 76.094 (3), 82.718 (3) |
V (Å3) | 596.32 (6) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.20 × 0.20 × 0.08 |
Data collection | |
Diffractometer | Nonius KappaCCD diffractometer |
Absorption correction | Multi-scan (SORTAV; Blessing, 1995) |
Tmin, Tmax | 0.873, 0.995 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 6535, 2685, 1771 |
Rint | 0.047 |
(sin θ/λ)max (Å−1) | 0.649 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.054, 0.156, 1.03 |
No. of reflections | 2685 |
No. of parameters | 172 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.25, −0.25 |
Computer programs: COLLECT (Nonius, 2002), DENZO-SMN (Otwinowski & Minor, 1997), SIR92 (Altomare et al., 1994), SHELXTL (Sheldrick, 2008), PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1N···O1i | 0.93 (2) | 1.94 (2) | 2.864 (2) | 173 (2) |
N2—H2N···Cg1ii | 0.87 (2) | 2.46 (2) | 3.322 (2) | 165 (2) |
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) −x, −y+1, −z+2. |
Acknowledgements
The authors are grateful for financial support from the American Chemical Society Petroleum Research Fund, the Dean's Seed Fund Initiative (Ryerson University), NSERC Canada and the University of Toronto.
References
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This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
The title compound is a meso-compound, and is therefore achiral. The trans-isomer is chiral, and both antipodal isomers have been synthesized (Sankhavasi et al., 1991). The crystal structure of the (4R,5R)-isomer has already been determined (Siegler & Long, 2006). Enantiopure samples of the trans-isomers have found use as precursors for chiral auxiliaries (Sankhavasi et al., 1991), chiral catalysts (Isobe et al., 1998), and chiral ligands (Lou et al., 2004). The title compound might also be of similar use if desymmetrization can be accomplished by selective reaction of one of the two enantiotopic nitrogen atoms, for instance using an enantioselective Buchwald-Hartwig reaction (Porosa & Viirre (2009).
The title compound was prepared according to the reaction scheme shown in Fig. 3. The imine-amide precursor is readily prepared by heating benzaldehyde with NH4OAc according to a literature procedure (Proskurnina et al., 2002). This compound was subjected to exhaustive hydrolysis, by heating in a mixture of HBr and acetic acid for four days, and the resultant meso-diamine was then treated with carbonyl diimidazole, resulting in the title compound.
The molecular structure is shown in Fig. 1 and confirms the cis-relationship between the phenyl groups at the 4 and 5 positions (atoms C1 and C3 by the crystallographic labelling scheme). This relative stereochemistry is initially set in the formation of the imine-amide species, which involves an electrocyclization governed by orbital symmetry considerations. Epimerization did not occur, even upon prolonged exposure to strong acid and heat in the hydrolysis of the imine and amide groups.
The dihedral angle between the two phenyl rings (C4—C9 and C10—C15) is 48.14 (6)°. In the crystal structure, intermolecular N—H···O hydrogen bonds link molecules into centrostmmetric dimers (Fig. 2). These dimers, are in turn, linked into a two-dimensional network via weak N—H···π(arene) interactions and π–π stacking interactions with Cg1···Cg1(-x, 2 - y, 1 - z) = 3.6937 (11) Å, where Cg1 is the centroid defined by ring atoms C4—C9.