(4RS)-Methyl 4-cyano-4-cyclo­hexyl-4-phenyl­butano­ate

Sun, G.-S.; Hu, Y.-L.; Huang, D.-F.; Xu, C.-M.

doi:10.1107/S1600536812021320

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 68| Part 6| June 2012| Page o1894

doi:10.1107/S1600536812021320

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(4RS)-Methyl 4-cyano-4-cyclohexyl-4-phenylbutanoate

Gui-Sheng Sun,^a Yu-Lai Hu,^a ^* Dan-Feng Huang ^a and Chang-Ming Xu ^a

^aCollege of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu Province 730070, People's Republic of China
^*Correspondence e-mail: huylai@163.com

(Received 19 April 2012; accepted 10 May 2012; online 26 May 2012)

In the crystal structure of the title compound, C₁₈H₂₃NO₂, there are only van der Waals interactions present. The cyclohexyl ring has a chair conformation. The longer axes of the displacement parameters of the non-H atoms forming the ethylmethylcarboxylate skeleton are perpendicular to the plane through the non-H atoms of this skeleton.

Related literature

For general background to pharmaceutical applications of methyl 4-cyano-4-cyclohexyl-4-phenylbutanoates, see: Hartmann & Batzl (1986 ), Hartmann et al. (1992 ); Fadel & Garcia-Argote (1996 ).

Experimental

Crystal data

C₁₈H₂₃NO₂
M_r = 285.37
Monoclinic, P 2₁ /c
a = 8.877 (6) Å
b = 9.120 (6) Å
c = 20.690 (14) Å
β = 95.769 (6)°
V = 1666.5 (19) Å³
Z = 4
Mo Kα radiation
μ = 0.07 mm⁻¹
T = 296 K
0.23 × 0.21 × 0.19 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2008a ) T_min = 0.983, T_max = 0.986
13440 measured reflections
3816 independent reflections
2026 reflections with I > 2σ(I)
R_int = 0.041

Refinement

R[F² > 2σ(F²)] = 0.052
wR(F²) = 0.153
S = 1.06
3816 reflections
192 parameters
H-atom parameters constrained
Δρ_max = 0.24 e Å⁻³
Δρ_min = −0.20 e Å⁻³

Data collection: APEX2 (Bruker, 2008 ); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008b ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008b); molecular graphics: SHELXTL (Sheldrick, 2008b); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812021320/fb2251sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812021320/fb2251Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812021320/fb2251Isup3.cml

checkCIF report

Comment top

Methyl 4-cyano-4-cyclohexyl-4-phenylbutanoates have attracted widespread attention as a pharmaceutical material to synthesis of 3-(4-aminophenyl)-3-cyclohexylpiperidine-2,6-dione (Fadel & Garcia-Argote, 1996). A variety of 3-(4-aminophenyl)-3-cyclohexylpiperidine-2,6-dione derivatives have been screened as inhibitors of human placental aromatase and treatment of estrogen-dependent diseases (Hartmann & Batzl, 1986, and Hartmann et al., 1992).

The title molecule is shown in Fig. 1. The cyclohexane ring adopts a chair conformation. There are no weak hydrogen bonds and no significant intermolecular π–π electron interactions in the structure. The longer axes of the displacement parameters of the non-hydrogen atoms forming the ethylmethylcarboxylate skeleton are perpendicular to the plane through the non-hydrogen atoms through this skeleton. The displacement parameters of these atoms are rather elongated, possibly due to weak intermolecular interactions between the molecules which may enable more intense thermal agitation of the molecules in the structure.

Fig. 2 shows the packing of the molecules in the title structure.

Related literature top

For general background to pharmaceutical applications of methyl 4-cyano-4-cyclohexyl-4-phenylbutanoates, see: Hartmann & Batzl (1986), Hartmann et al. (1992); Fadel & Garcia-Argote (1996).

Experimental top

Powdered potassium carbonate (6.9 g, 0.05 mol) and tetrabutylammonium bromide (0.8 g, 0.0025 mol) were added to a solution of 2-cyclohexyl-2-phenylacetonitrile (9.95 g, 0.05 mol) in toluene (35 ml). Methyl acrylate (5.16 g, 0.06 mol) was slowly added in the mixture at 110 °C. After refluxing for 7h, the mixture was cooled and water was added, extracted with ethyl acetate (3 × 50 ml), combined organic solutions, washed with water (3 × 50 ml), and dried over MgSO₄. The volatiles were removed in vacuo and the crude product was purified by column chromatography over silica gel with ethyl acetate/petroleum ether (1:20 v/v). The title compound was isolated in 96% yield as a white solid. Colourless transparent block-like crystals with approx. dimensions 0.2 × 0.4 × 0.5 mm were obtained by slow evaporation of ethyl acetate/petroleum ether (1:20 v/v).

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008b); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008b); molecular graphics: SHELXTL (Sheldrick, 2008b); software used to prepare material for publication: SHELXTL (Sheldrick, 2008b).

Figures top

	Fig. 1. The title molecule with the atom labels and the displacement ellipsoids shown at the 30% probability level.
	Fig. 2. A packing diagram, viewed approximately along the b axis. Applied colourse for the atomic species: C - grey, H - green, N - blue; O - red.

(4RS)-Methyl 4-cyano-4-cyclohexyl-4-phenylbutanoate top

Crystal data top

C₁₈H₂₃NO₂	F(000) = 616
M_r = 285.37	D_x = 1.137 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2935 reflections
a = 8.877 (6) Å	θ = 2.4–24.9°
b = 9.120 (6) Å	µ = 0.07 mm⁻¹
c = 20.690 (14) Å	T = 296 K
β = 95.769 (6)°	Block, colourless
V = 1666.5 (19) Å³	0.23 × 0.21 × 0.19 mm
Z = 4

Data collection top

Bruker APEXII CCD diffractometer	3816 independent reflections
Radiation source: fine-focus sealed tube	2026 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.041
ϕ and ω scans	θ_max = 27.5°, θ_min = 2.4°
Absorption correction: multi-scan (SADABS; Sheldrick, 2008a)	h = −11→11
T_min = 0.983, T_max = 0.986	k = −10→11
13440 measured reflections	l = −26→26

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F² > 2σ(F²)] = 0.052	H-atom parameters constrained
wR(F²) = 0.153	w = 1/[σ²(F_o²) + (0.0382P)² + 0.7938P] where P = (F_o² + 2F_c²)/3
S = 1.06	(Δ/σ)_max < 0.001
3816 reflections	Δρ_max = 0.24 e Å⁻³
192 parameters	Δρ_min = −0.20 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008b), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
91 constraints	Extinction coefficient: 0.0181 (18)
Primary atom site location: structure-invariant direct methods

Crystal data top

C₁₈H₂₃NO₂	V = 1666.5 (19) Å³
M_r = 285.37	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 8.877 (6) Å	µ = 0.07 mm⁻¹
b = 9.120 (6) Å	T = 296 K
c = 20.690 (14) Å	0.23 × 0.21 × 0.19 mm
β = 95.769 (6)°

Data collection top

Bruker APEXII CCD diffractometer	3816 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2008a)	2026 reflections with I > 2σ(I)
T_min = 0.983, T_max = 0.986	R_int = 0.041
13440 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.052	0 restraints
wR(F²) = 0.153	H-atom parameters constrained
S = 1.06	Δρ_max = 0.24 e Å⁻³
3816 reflections	Δρ_min = −0.20 e Å⁻³
192 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
C1	0.2736 (3)	0.2805 (2)	0.70020 (10)	0.0531 (6)
H1	0.3761	0.2581	0.7018	0.064*
C2	0.1862 (3)	0.2158 (3)	0.74406 (11)	0.0652 (7)
H2	0.2305	0.1505	0.7748	0.078*
C3	0.0358 (3)	0.2470 (3)	0.74258 (12)	0.0666 (7)
H3	−0.0221	0.2035	0.7723	0.080*
C4	−0.0298 (3)	0.3430 (3)	0.69695 (12)	0.0613 (6)
H4	−0.1326	0.3639	0.6956	0.074*
C5	0.0566 (2)	0.4086 (3)	0.65311 (11)	0.0537 (6)
H5	0.0116	0.4740	0.6225	0.064*
C6	0.2101 (2)	0.3778 (2)	0.65421 (9)	0.0431 (5)
C7	0.3020 (2)	0.4512 (2)	0.60391 (9)	0.0438 (5)
C8	0.3038 (2)	0.6215 (2)	0.61212 (10)	0.0478 (5)
H8	0.1991	0.6555	0.6031	0.057*
C9	0.3583 (3)	0.6683 (2)	0.68142 (10)	0.0539 (6)
H9A	0.2947	0.6233	0.7113	0.065*
H9B	0.4611	0.6339	0.6924	0.065*
C10	0.3539 (3)	0.8345 (3)	0.68922 (12)	0.0664 (7)
H10A	0.2500	0.8681	0.6819	0.080*
H10B	0.3924	0.8605	0.7333	0.080*
C11	0.4475 (3)	0.9097 (3)	0.64200 (15)	0.0814 (8)
H11A	0.4389	1.0152	0.6465	0.098*
H11B	0.5532	0.8832	0.6517	0.098*
C12	0.3937 (4)	0.8653 (3)	0.57336 (14)	0.0828 (9)
H12A	0.4576	0.9109	0.5437	0.099*
H12B	0.2911	0.9004	0.5625	0.099*
C13	0.3972 (3)	0.6996 (3)	0.56456 (12)	0.0712 (8)
H13A	0.5011	0.6656	0.5712	0.085*
H13B	0.3576	0.6751	0.5205	0.085*
C14	0.4603 (3)	0.3992 (3)	0.61248 (10)	0.0525 (6)
C15	0.2354 (3)	0.4061 (2)	0.53446 (10)	0.0519 (6)
H15A	0.1331	0.4440	0.5265	0.062*
H15B	0.2954	0.4507	0.5031	0.062*
C16	0.2321 (3)	0.2420 (3)	0.52422 (11)	0.0638 (7)
H16A	0.3351	0.2051	0.5299	0.077*
H16B	0.1773	0.1972	0.5574	0.077*
C17	0.1604 (3)	0.1957 (3)	0.45895 (11)	0.0600 (6)
C18	0.1176 (4)	−0.0077 (4)	0.38785 (14)	0.1048 (11)
H18A	0.1542	0.0453	0.3525	0.157*
H18B	0.0091	−0.0021	0.3846	0.157*
H18C	0.1481	−0.1085	0.3860	0.157*
N1	0.5830 (3)	0.3602 (3)	0.61735 (10)	0.0782 (7)
O1	0.0970 (3)	0.2726 (2)	0.41959 (11)	0.1196 (9)
O2	0.1799 (3)	0.0558 (2)	0.44876 (9)	0.0983 (7)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0528 (13)	0.0558 (14)	0.0509 (12)	0.0029 (11)	0.0056 (10)	0.0068 (11)
C2	0.0753 (18)	0.0634 (17)	0.0575 (14)	−0.0026 (14)	0.0097 (12)	0.0161 (12)
C3	0.0739 (18)	0.0654 (17)	0.0638 (15)	−0.0129 (14)	0.0233 (13)	0.0035 (13)
C4	0.0519 (14)	0.0630 (16)	0.0714 (16)	−0.0043 (12)	0.0185 (12)	−0.0075 (13)
C5	0.0542 (14)	0.0514 (14)	0.0556 (13)	0.0078 (11)	0.0065 (10)	0.0024 (11)
C6	0.0487 (12)	0.0408 (12)	0.0401 (10)	0.0021 (9)	0.0063 (9)	−0.0015 (9)
C7	0.0475 (12)	0.0452 (13)	0.0393 (10)	0.0096 (10)	0.0066 (9)	0.0034 (9)
C8	0.0526 (13)	0.0461 (13)	0.0456 (11)	0.0047 (10)	0.0086 (9)	0.0050 (10)
C9	0.0567 (14)	0.0526 (14)	0.0534 (13)	−0.0002 (11)	0.0096 (10)	0.0007 (11)
C10	0.0753 (17)	0.0576 (16)	0.0672 (16)	0.0004 (13)	0.0113 (13)	−0.0077 (13)
C11	0.095 (2)	0.0509 (16)	0.101 (2)	−0.0073 (15)	0.0258 (17)	−0.0033 (15)
C12	0.115 (2)	0.0532 (17)	0.085 (2)	−0.0024 (16)	0.0358 (17)	0.0148 (15)
C13	0.101 (2)	0.0556 (16)	0.0617 (15)	−0.0003 (14)	0.0320 (14)	0.0084 (12)
C14	0.0559 (14)	0.0576 (15)	0.0452 (12)	0.0075 (12)	0.0116 (10)	0.0051 (10)
C15	0.0653 (14)	0.0503 (14)	0.0398 (11)	0.0109 (11)	0.0045 (10)	0.0034 (10)
C16	0.0911 (19)	0.0530 (15)	0.0457 (12)	0.0089 (13)	−0.0007 (12)	0.0013 (11)
C17	0.0696 (16)	0.0571 (16)	0.0514 (13)	0.0059 (13)	−0.0031 (11)	0.0007 (12)
C18	0.143 (3)	0.085 (2)	0.081 (2)	−0.026 (2)	−0.0188 (19)	−0.0271 (18)
N1	0.0605 (14)	0.0992 (19)	0.0761 (15)	0.0187 (13)	0.0131 (11)	0.0069 (13)
O1	0.175 (2)	0.0836 (16)	0.0866 (15)	0.0319 (15)	−0.0539 (15)	−0.0107 (12)
O2	0.158 (2)	0.0592 (13)	0.0704 (12)	0.0056 (12)	−0.0256 (12)	−0.0117 (10)

Geometric parameters (Å, º) top

C1—C6	1.379 (3)	C10—H10B	0.9700
C1—C2	1.384 (3)	C11—C12	1.508 (4)
C1—H1	0.9300	C11—H11A	0.9700
C2—C3	1.362 (3)	C11—H11B	0.9700
C2—H2	0.9300	C12—C13	1.523 (4)
C3—C4	1.374 (4)	C12—H12A	0.9700
C3—H3	0.9300	C12—H12B	0.9700
C4—C5	1.382 (3)	C13—H13A	0.9700
C4—H4	0.9300	C13—H13B	0.9700
C5—C6	1.389 (3)	C14—N1	1.140 (3)
C5—H5	0.9300	C15—C16	1.512 (3)
C6—C7	1.538 (3)	C15—H15A	0.9700
C7—C14	1.477 (3)	C15—H15B	0.9700
C7—C15	1.553 (3)	C16—C17	1.495 (3)
C7—C8	1.562 (3)	C16—H16A	0.9700
C8—C13	1.525 (3)	C16—H16B	0.9700
C8—C9	1.528 (3)	C17—O1	1.174 (3)
C8—H8	0.9800	C17—O2	1.308 (3)
C9—C10	1.525 (3)	C18—O2	1.445 (3)
C9—H9A	0.9700	C18—H18A	0.9600
C9—H9B	0.9700	C18—H18B	0.9600
C10—C11	1.510 (4)	C18—H18C	0.9600
C10—H10A	0.9700

C6—C1—C2	120.6 (2)	C12—C11—C10	110.1 (2)
C6—C1—H1	119.7	C12—C11—H11A	109.6
C2—C1—H1	119.7	C10—C11—H11A	109.6
C3—C2—C1	120.6 (2)	C12—C11—H11B	109.6
C3—C2—H2	119.7	C10—C11—H11B	109.6
C1—C2—H2	119.7	H11A—C11—H11B	108.1
C2—C3—C4	119.7 (2)	C11—C12—C13	111.8 (2)
C2—C3—H3	120.1	C11—C12—H12A	109.3
C4—C3—H3	120.1	C13—C12—H12A	109.3
C3—C4—C5	120.1 (2)	C11—C12—H12B	109.3
C3—C4—H4	119.9	C13—C12—H12B	109.3
C5—C4—H4	119.9	H12A—C12—H12B	107.9
C4—C5—C6	120.7 (2)	C12—C13—C8	111.6 (2)
C4—C5—H5	119.7	C12—C13—H13A	109.3
C6—C5—H5	119.7	C8—C13—H13A	109.3
C1—C6—C5	118.2 (2)	C12—C13—H13B	109.3
C1—C6—C7	122.61 (19)	C8—C13—H13B	109.3
C5—C6—C7	119.14 (18)	H13A—C13—H13B	108.0
C14—C7—C6	110.00 (17)	N1—C14—C7	178.1 (2)
C14—C7—C15	107.19 (17)	C16—C15—C7	113.07 (17)
C6—C7—C15	109.40 (18)	C16—C15—H15A	109.0
C14—C7—C8	107.87 (18)	C7—C15—H15A	109.0
C6—C7—C8	111.05 (16)	C16—C15—H15B	109.0
C15—C7—C8	111.26 (16)	C7—C15—H15B	109.0
C13—C8—C9	109.49 (19)	H15A—C15—H15B	107.8
C13—C8—C7	113.23 (18)	C17—C16—C15	113.97 (19)
C9—C8—C7	112.28 (17)	C17—C16—H16A	108.8
C13—C8—H8	107.2	C15—C16—H16A	108.8
C9—C8—H8	107.2	C17—C16—H16B	108.8
C7—C8—H8	107.2	C15—C16—H16B	108.8
C10—C9—C8	111.61 (19)	H16A—C16—H16B	107.7
C10—C9—H9A	109.3	O1—C17—O2	122.2 (2)
C8—C9—H9A	109.3	O1—C17—C16	126.1 (2)
C10—C9—H9B	109.3	O2—C17—C16	111.7 (2)
C8—C9—H9B	109.3	O2—C18—H18A	109.5
H9A—C9—H9B	108.0	O2—C18—H18B	109.5
C11—C10—C9	111.2 (2)	H18A—C18—H18B	109.5
C11—C10—H10A	109.4	O2—C18—H18C	109.5
C9—C10—H10A	109.4	H18A—C18—H18C	109.5
C11—C10—H10B	109.4	H18B—C18—H18C	109.5
C9—C10—H10B	109.4	C17—O2—C18	119.1 (2)
H10A—C10—H10B	108.0

C6—C1—C2—C3	0.0 (4)	C6—C7—C8—C9	53.8 (2)
C1—C2—C3—C4	0.3 (4)	C15—C7—C8—C9	175.90 (17)
C2—C3—C4—C5	−0.5 (4)	C13—C8—C9—C10	55.4 (3)
C3—C4—C5—C6	0.4 (4)	C7—C8—C9—C10	−177.91 (19)
C2—C1—C6—C5	−0.1 (3)	C8—C9—C10—C11	−57.1 (3)
C2—C1—C6—C7	−179.3 (2)	C9—C10—C11—C12	56.5 (3)
C4—C5—C6—C1	−0.1 (3)	C10—C11—C12—C13	−56.4 (3)
C4—C5—C6—C7	179.1 (2)	C11—C12—C13—C8	56.4 (3)
C1—C6—C7—C14	1.1 (3)	C9—C8—C13—C12	−54.9 (3)
C5—C6—C7—C14	−178.02 (19)	C7—C8—C13—C12	179.0 (2)
C1—C6—C7—C15	118.6 (2)	C14—C7—C15—C16	62.0 (2)
C5—C6—C7—C15	−60.5 (2)	C6—C7—C15—C16	−57.2 (2)
C1—C6—C7—C8	−118.2 (2)	C8—C7—C15—C16	179.7 (2)
C5—C6—C7—C8	62.6 (2)	C7—C15—C16—C17	176.7 (2)
C14—C7—C8—C13	57.8 (2)	C15—C16—C17—O1	−7.4 (4)
C6—C7—C8—C13	178.43 (18)	C15—C16—C17—O2	170.7 (2)
C15—C7—C8—C13	−59.5 (3)	O1—C17—O2—C18	−1.8 (5)
C14—C7—C8—C9	−66.8 (2)	C16—C17—O2—C18	180.0 (2)

Experimental details

Crystal data
Chemical formula	C₁₈H₂₃NO₂
M_r	285.37
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	296
a, b, c (Å)	8.877 (6), 9.120 (6), 20.690 (14)
β (°)	95.769 (6)
V (Å³)	1666.5 (19)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.07
Crystal size (mm)	0.23 × 0.21 × 0.19

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2008a)
T_min, T_max	0.983, 0.986
No. of measured, independent and observed [I > 2σ(I)] reflections	13440, 3816, 2026
R_int	0.041
(sin θ/λ)_max (Å⁻¹)	0.650

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.052, 0.153, 1.06
No. of reflections	3816
No. of parameters	192
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.24, −0.20

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008b), SHELXL97 (Sheldrick, 2008b), SHELXTL (Sheldrick, 2008b).

Acknowledgements

This work was supported by the Key Laboratory of Polymer Materials of Gansu Province (Northwest Normal University).

References

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