meso-4,5-Diphenyl­imidazolidin-2-one

Galas, H.; Viirre, R.D.; Lough, A.J.

doi:10.1107/S1600536809046133

organic compounds

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ISSN: 2056-9890

Volume 65| Part 12| December 2009| Page o3087

doi:10.1107/S1600536809046133

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meso-4,5-Diphenylimidazolidin-2-one

Henry Galas,^a Russell D. Viirre ^a and Alan J. Lough ^b ^*

^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

(Received 29 October 2009; accepted 2 November 2009; online 14 November 2009)

The crystal structure determination of the title compound, C₁₅H₁₄N₂O, 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 crystal structure, 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.

Related 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 crystal structure 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

C₁₅H₁₄N₂O
M_r = 238.28
Triclinic, $[P \overline 1]$
a = 6.3539 (4) Å
b = 8.6159 (4) Å
c = 11.3211 (7) Å
α = 86.147 (3)°
β = 76.094 (3)°
γ = 82.718 (3)°
V = 596.32 (6) Å³
Z = 2
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 150 K
0.20 × 0.20 × 0.08 mm

Data collection

Nonius KappaCCD diffractometer
Absorption correction: multi-scan (SORTAV; Blessing, 1995 ) T_min = 0.873, T_max = 0.995
6535 measured reflections
2685 independent reflections
1771 reflections with I > 2σ(I)
R_int = 0.047

Refinement

R[F² > 2σ(F²)] = 0.054
wR(F²) = 0.156
S = 1.03
2685 reflections
172 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.25 e Å⁻³
Δρ_min = −0.25 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

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. Cg1 is the centroid of the C4–C9 ring.

Data collection: COLLECT (Nonius, 2002 ); cell refinement: 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

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809046133/sj2668sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809046133/sj2668Isup2.hkl

checkCIF report

Comment top

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.

Related literature top

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 crystal structure 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). Cg1 is the centroid of the C4–C9 ring.

Experimental top

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.

Computing details top

Data collection: COLLECT (Nonius, 2002); cell refinement: 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).

Figures top

	Fig. 1. The molecular structure showing 30% probability displacement ellipsoids (arbitrary spheres for H atoms).
	Fig. 2. Part of the crystal structure showing hydrogen bonds as dashed lines.
	Fig. 3. The reaction scheme.

meso-4,5-Diphenylimidazolidin-2-one top

Crystal data top

C₁₅H₁₄N₂O	Z = 2
M_r = 238.28	F(000) = 252
Triclinic, P1	D_x = 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

Data collection top

Nonius KappaCCD diffractometer	2685 independent reflections
Radiation source: fine-focus sealed tube	1771 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.047
Detector resolution: 9 pixels mm^-1	θ_max = 27.5°, θ_min = 3.0°
ω scans	h = −8→8
Absorption correction: multi-scan (SORTAV; Blessing, 1995)	k = −11→11
T_min = 0.873, T_max = 0.995	l = −12→14
6535 measured reflections

Refinement top

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(F_o²) + (0.0787P)² + 0.1078P] where P = (F_o² + 2F_c²)/3
S = 1.03	(Δ/σ)_max < 0.001
2685 reflections	Δρ_max = 0.25 e Å⁻³
172 parameters	Δρ_min = −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)

Crystal data top

C₁₅H₁₄N₂O	γ = 82.718 (3)°
M_r = 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)°

Data collection top

Nonius KappaCCD diffractometer	2685 independent reflections
Absorption correction: multi-scan (SORTAV; Blessing, 1995)	1771 reflections with I > 2σ(I)
T_min = 0.873, T_max = 0.995	R_int = 0.047
6535 measured reflections

Refinement top

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	Δρ_max = 0.25 e Å⁻³
2685 reflections	Δρ_min = −0.25 e Å⁻³
172 parameters

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

	x	y	z	U_iso*/U_eq
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)*

Atomic displacement parameters (Å²) top

	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)

Geometric parameters (Å, º) top

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

Hydrogen-bond geometry (Å, º) top

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
M_r	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)
T_min, T_max	0.873, 0.995
No. of measured, independent and observed [I > 2σ(I)] reflections	6535, 2685, 1771
R_int	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
Δρ_max, Δρ_min (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).

Hydrogen-bond geometry (Å, º) top

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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