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Acta Cryst. (2009). E65, o11    [ doi:10.1107/S1600536808040063 ]

1-Dichloroacetyl-r-2,c-6-bis(4-methoxyphenyl)-c-3,t-3-dimethylpiperidin-4-one

M. Thenmozhi, S. Ponnuswamy, V. Mohanraj, R. Vijayalakshmi and M. N. Ponnuswamy

Abstract top

In the title compound, C23H25Cl2NO4, the piperidine ring adopts a distorted boat conformation. Inversion-related molecules are linked into centrosymmetric R22(16) dimers by paired C-H...O hydrogen bonds, and the dimers are connected via C-H...O hydrogen bonds into a chain running along [101].

Comment top

The piperidine compounds are used in chemical industry for the synthesis of pharmacological drugs, either as reactants, solvents or being units of molecular chemical structure of the final compounds. These compounds have significant biological importance with more environmental impact (Ribeiro da Silva et al., 2007). A significant industrial application of piperidine is for the production of dipiperidinyl dithiuram tetrasulfide, which is used as a rubber vulcanization accelerator (Eller et al., 2002).

The piperidine ring adopts a distorted boat conformation, with puckering parameters (Cremer & Pople, 1975) q2 = 0.606 (2) Å, q3 = 0.127 (2) Å, and φ = 77.5 (2)°, and asymmetry parameter Δs(C2) = 18.26 (17)° (Nardelli, 1983). The torsion angles C13—C12—O2—C15 [2.6 (3)°] and C20—C21—O4—C24 [-11.7 (3)°] indicate that the methoxy groups are almost coplanar with the attached rings (Fig.1). The sum of the bond angles around atom N1 (359.4°) of the piperidine ring is in accordance with sp2 hybridization (Beddoes et al., 1986). The best plane through the piperidine ring (N1/C3/C4/C6) and methoxyphenyl ring (C9—C14) are orthogonal to one another, with a dihedral angle of 87.18 (7)°, whereas, the other methoxyphenyl ring (C18—C23) is oriented at an angle of 54.47 (7)°.

The molecules at positions (x, y, z) and (1 - x, 1 - y, 1 - z) are linked through a pair of C13—H13···O3 hydrogen bonds forming a cyclic centrosymmetric R22(16) dimer (Bernstein et al., 1995). The dimers are linked by intermolecular C6—H6···O1 hydrogen bonds (Table 1) into a chain running along the [101] (Fig.2).

Related literature top

For general background, see: Eller et al.(2002); Ribeiro da Silva et al. (2007). For hybridization, see: Beddoes et al. (1986) For hydrogen-bond motifs, see: Bernstein et al. (1995). For ring conformational analysis, see: Cremer & Pople (1975); Nardelli (1983).

Experimental top

To the solution of r-2,c-6-bis(4-methoxyphenyl)-c-3,t-3-dimethylpiperidin-4-one (2 g) in benzene (25 ml), triethylamine (2.0 ml) and dichloroacetyl chloride (1.40 ml) were added and allowed to reflux on a water bath for 5 h. The course of the reaction was monitored by TLC. The solution was concentrated and the resulting mass was crystallized from ethanol.

Refinement top

H atoms were positioned geometrically (C—H = 0.93–0.98 Å) and allowed to ride on their parent atoms, with Uiso(H) = 1.2–1.5(methyl) Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXS97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2003).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing 50% probability displacement ellipsoids.
[Figure 2] Fig. 2. The crystal packing of the molecules viewed down b axis. Hydrogen bonds are shown as dashed lines.
1-Dichloroacetyl-r-2,c-6-bis(4-methoxyphenyl)-c-3,t-3-dimethylpiperidin-4-one top
Crystal data top
C23H25Cl2NO4F(000) = 1888
Mr = 450.34Dx = 1.327 Mg m−3
Monoclinic, C2/cMelting point = 377–379 K
Hall symbol: -C 2ycMo Kα radiation, λ = 0.71073 Å
a = 23.6295 (9) ÅCell parameters from 6905 reflections
b = 10.3999 (4) Åθ = 2.2–30.6°
c = 19.2617 (9) ŵ = 0.32 mm−1
β = 107.734 (1)°T = 293 K
V = 4508.5 (3) Å3Block, colourless
Z = 80.30 × 0.25 × 0.20 mm
Data collection top
Bruker Kappa APEXII area-detector
diffractometer		6905 independent reflections
Radiation source: fine-focus sealed tube4138 reflections with I > 2σ(I)
graphiteRint = 0.031
ω and φ scansθmax = 30.6°, θmin = 2.2°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2001)		h = −32→33
Tmin = 0.911, Tmax = 0.939k = −14→14
29354 measured reflectionsl = −27→27
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)] = 0.056Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.184H-atom parameters constrained
S = 1.00 w = 1/[σ2(Fo2) + (0.0869P)2 + 2.9239P]
where P = (Fo2 + 2Fc2)/3
6905 reflections(Δ/σ)max = 0.001
275 parametersΔρmax = 0.60 e Å−3
0 restraintsΔρmin = −0.63 e Å−3
Crystal data top
C23H25Cl2NO4V = 4508.5 (3) Å3
Mr = 450.34Z = 8
Monoclinic, C2/cMo Kα radiation
a = 23.6295 (9) ŵ = 0.32 mm−1
b = 10.3999 (4) ÅT = 293 K
c = 19.2617 (9) Å0.30 × 0.25 × 0.20 mm
β = 107.734 (1)°
Data collection top
Bruker Kappa APEXII area-detector
diffractometer		6905 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2001)		4138 reflections with I > 2σ(I)
Tmin = 0.911, Tmax = 0.939Rint = 0.031
29354 measured reflectionsθmax = 30.6°
Refinement top
R[F2 > 2σ(F2)] = 0.056H-atom parameters constrained
wR(F2) = 0.184Δρmax = 0.60 e Å−3
S = 1.00Δρmin = −0.63 e Å−3
6905 reflectionsAbsolute structure: ?
275 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
Cl10.18029 (3)0.52254 (7)0.14172 (4)0.0790 (2)
Cl20.26274 (4)0.62339 (11)0.07261 (4)0.1127 (4)
O10.26407 (7)0.74756 (16)0.21261 (9)0.0635 (4)
O20.56012 (6)0.89254 (16)0.36906 (9)0.0604 (4)
O30.37036 (9)0.4204 (2)0.48165 (10)0.0798 (6)
O40.48349 (7)0.30777 (15)0.10880 (9)0.0592 (4)
N10.31916 (6)0.58476 (15)0.27717 (8)0.0402 (3)
C20.33601 (8)0.66580 (19)0.34377 (10)0.0407 (4)
H20.30920.74000.33250.049*
C30.32172 (8)0.5947 (2)0.40675 (11)0.0481 (5)
C40.35641 (9)0.4707 (2)0.42265 (12)0.0530 (5)
C50.37393 (9)0.4121 (2)0.36076 (12)0.0521 (5)
H5A0.37210.31940.36510.063*
H5B0.41510.43430.36760.063*
C60.33818 (8)0.44832 (19)0.28249 (11)0.0435 (4)
H60.30230.39500.26850.052*
C70.28061 (8)0.6362 (2)0.21725 (11)0.0460 (4)
C80.25568 (9)0.5486 (2)0.15090 (12)0.0550 (5)
H80.27710.46650.15870.066*
C90.39837 (8)0.72041 (18)0.35651 (10)0.0402 (4)
C100.40476 (8)0.81147 (19)0.30699 (10)0.0431 (4)
H100.37160.83570.26890.052*
C110.45865 (9)0.8669 (2)0.31249 (11)0.0476 (5)
H110.46160.92820.27860.057*
C120.50864 (8)0.83169 (19)0.36834 (11)0.0453 (4)
C130.50374 (8)0.7419 (2)0.41826 (11)0.0475 (5)
H130.53710.71760.45600.057*
C140.44863 (8)0.6872 (2)0.41224 (11)0.0474 (5)
H140.44560.62680.44660.057*
C150.61272 (11)0.8573 (4)0.4232 (2)0.1002 (11)
H15A0.60960.87930.47030.150*
H15B0.64570.90220.41540.150*
H15C0.61880.76630.42100.150*
C160.25568 (9)0.5548 (3)0.38209 (14)0.0630 (6)
H16A0.24870.49410.34280.095*
H16B0.23130.62930.36590.095*
H16C0.24590.51600.42220.095*
C170.33296 (11)0.6809 (3)0.47360 (12)0.0646 (6)
H17A0.32580.63320.51280.097*
H17B0.30670.75360.46210.097*
H17C0.37340.71010.48810.097*
C180.37492 (8)0.41315 (18)0.23272 (11)0.0416 (4)
C190.37935 (9)0.2855 (2)0.21607 (12)0.0498 (5)
H190.35760.22470.23260.060*
C200.41538 (9)0.2454 (2)0.17531 (12)0.0507 (5)
H200.41800.15870.16500.061*
C210.44721 (8)0.3353 (2)0.15026 (11)0.0458 (4)
C220.44278 (9)0.4630 (2)0.16603 (13)0.0533 (5)
H220.46400.52400.14880.064*
C230.40738 (9)0.5018 (2)0.20705 (13)0.0508 (5)
H230.40520.58850.21770.061*
C240.49748 (14)0.1779 (2)0.10196 (17)0.0750 (7)
H24A0.51280.14020.14950.113*
H24B0.52690.17210.07700.113*
H24C0.46230.13260.07470.113*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0512 (3)0.0880 (5)0.0926 (5)−0.0197 (3)0.0140 (3)0.0036 (4)
Cl20.1188 (7)0.1699 (10)0.0577 (4)−0.0632 (6)0.0394 (4)−0.0210 (5)
O10.0641 (9)0.0589 (10)0.0558 (9)0.0225 (8)0.0008 (7)0.0010 (7)
O20.0427 (7)0.0669 (10)0.0689 (10)−0.0084 (7)0.0130 (7)0.0073 (8)
O30.0847 (13)0.0963 (14)0.0611 (11)0.0211 (11)0.0265 (9)0.0364 (10)
O40.0632 (9)0.0547 (9)0.0686 (10)0.0045 (7)0.0332 (8)−0.0007 (8)
N10.0348 (7)0.0415 (8)0.0421 (8)0.0034 (6)0.0087 (6)0.0038 (7)
C20.0355 (8)0.0449 (10)0.0413 (9)0.0042 (7)0.0110 (7)0.0027 (8)
C30.0389 (9)0.0617 (13)0.0448 (10)0.0023 (8)0.0146 (8)0.0073 (9)
C40.0407 (9)0.0641 (14)0.0543 (12)0.0010 (9)0.0148 (9)0.0185 (10)
C50.0486 (10)0.0480 (12)0.0609 (13)0.0096 (9)0.0183 (9)0.0164 (10)
C60.0369 (8)0.0398 (10)0.0541 (11)−0.0008 (7)0.0143 (8)0.0053 (8)
C70.0381 (9)0.0522 (12)0.0449 (10)0.0084 (8)0.0084 (8)0.0022 (9)
C80.0396 (9)0.0657 (14)0.0514 (12)0.0050 (9)0.0015 (8)−0.0046 (10)
C90.0384 (8)0.0412 (10)0.0408 (9)0.0021 (7)0.0117 (7)0.0000 (8)
C100.0394 (9)0.0470 (11)0.0412 (9)0.0023 (8)0.0097 (7)0.0009 (8)
C110.0477 (10)0.0495 (11)0.0462 (11)−0.0009 (8)0.0151 (8)0.0052 (9)
C120.0398 (9)0.0460 (11)0.0505 (11)−0.0016 (8)0.0145 (8)−0.0059 (9)
C130.0386 (9)0.0509 (12)0.0479 (11)0.0033 (8)0.0057 (8)0.0023 (9)
C140.0426 (9)0.0511 (12)0.0457 (10)0.0006 (8)0.0093 (8)0.0080 (9)
C150.0412 (12)0.117 (3)0.126 (3)−0.0143 (14)0.0005 (14)0.044 (2)
C160.0400 (10)0.0862 (18)0.0664 (14)−0.0007 (10)0.0214 (10)0.0106 (13)
C170.0607 (13)0.0883 (18)0.0478 (12)0.0039 (12)0.0212 (10)0.0006 (12)
C180.0352 (8)0.0387 (10)0.0502 (10)0.0000 (7)0.0119 (7)0.0025 (8)
C190.0501 (10)0.0419 (11)0.0592 (12)−0.0088 (8)0.0193 (9)0.0019 (9)
C200.0554 (11)0.0383 (11)0.0584 (12)−0.0018 (9)0.0172 (10)−0.0034 (9)
C210.0419 (9)0.0483 (11)0.0463 (10)0.0025 (8)0.0122 (8)0.0024 (9)
C220.0521 (11)0.0441 (11)0.0693 (14)−0.0048 (9)0.0268 (10)0.0041 (10)
C230.0504 (11)0.0363 (10)0.0708 (14)−0.0005 (8)0.0258 (10)0.0009 (9)
C240.0880 (18)0.0611 (16)0.0897 (19)0.0135 (13)0.0475 (16)−0.0023 (14)
Geometric parameters (Å, °) top
Cl1—C81.757 (2)C11—C121.383 (3)
Cl2—C81.749 (2)C11—H110.93
O1—C71.217 (2)C12—C131.370 (3)
O2—C121.368 (2)C13—C141.393 (3)
O2—C151.406 (3)C13—H130.93
O3—C41.202 (3)C14—H140.93
O4—C211.368 (2)C15—H15A0.96
O4—C241.406 (3)C15—H15B0.96
N1—C71.344 (2)C15—H15C0.96
N1—C61.483 (2)C16—H16A0.96
N1—C21.484 (2)C16—H16B0.96
C2—C91.528 (2)C16—H16C0.96
C2—C31.544 (3)C17—H17A0.96
C2—H20.98C17—H17B0.96
C3—C41.508 (3)C17—H17C0.96
C3—C171.524 (3)C18—C191.377 (3)
C3—C161.543 (3)C18—C231.383 (3)
C4—C51.505 (3)C19—C201.387 (3)
C5—C61.534 (3)C19—H190.93
C5—H5A0.97C20—C211.376 (3)
C5—H5B0.97C20—H200.93
C6—C181.521 (3)C21—C221.373 (3)
C6—H60.98C22—C231.374 (3)
C7—C81.533 (3)C22—H220.93
C8—H80.98C23—H230.93
C9—C141.380 (3)C24—H24A0.96
C9—C101.385 (3)C24—H24B0.96
C10—C111.372 (3)C24—H24C0.96
C10—H100.93
C12—O2—C15117.99 (19)O2—C12—C11115.57 (18)
C21—O4—C24117.58 (18)C13—C12—C11119.45 (18)
C7—N1—C6123.51 (16)C12—C13—C14119.78 (18)
C7—N1—C2116.70 (15)C12—C13—H13120.1
C6—N1—C2119.19 (15)C14—C13—H13120.1
N1—C2—C9109.97 (14)C9—C14—C13121.55 (19)
N1—C2—C3109.99 (16)C9—C14—H14119.2
C9—C2—C3118.89 (16)C13—C14—H14119.2
N1—C2—H2105.7O2—C15—H15A109.5
C9—C2—H2105.7O2—C15—H15B109.5
C3—C2—H2105.7H15A—C15—H15B109.5
C4—C3—C17112.76 (18)O2—C15—H15C109.5
C4—C3—C16105.59 (19)H15A—C15—H15C109.5
C17—C3—C16108.54 (17)H15B—C15—H15C109.5
C4—C3—C2109.49 (15)C3—C16—H16A109.5
C17—C3—C2111.01 (18)C3—C16—H16B109.5
C16—C3—C2109.25 (17)H16A—C16—H16B109.5
O3—C4—C5120.7 (2)C3—C16—H16C109.5
O3—C4—C3122.7 (2)H16A—C16—H16C109.5
C5—C4—C3116.68 (17)H16B—C16—H16C109.5
C4—C5—C6118.50 (17)C3—C17—H17A109.5
C4—C5—H5A107.7C3—C17—H17B109.5
C6—C5—H5A107.7H17A—C17—H17B109.5
C4—C5—H5B107.7C3—C17—H17C109.5
C6—C5—H5B107.7H17A—C17—H17C109.5
H5A—C5—H5B107.1H17B—C17—H17C109.5
N1—C6—C18113.94 (15)C19—C18—C23117.99 (18)
N1—C6—C5111.57 (16)C19—C18—C6118.50 (17)
C18—C6—C5108.14 (15)C23—C18—C6123.37 (18)
N1—C6—H6107.6C18—C19—C20121.69 (18)
C18—C6—H6107.6C18—C19—H19119.2
C5—C6—H6107.6C20—C19—H19119.2
O1—C7—N1124.06 (19)C21—C20—C19119.30 (19)
O1—C7—C8118.08 (18)C21—C20—H20120.3
N1—C7—C8117.85 (18)C19—C20—H20120.3
C7—C8—Cl2109.96 (16)O4—C21—C22115.80 (18)
C7—C8—Cl1107.21 (15)O4—C21—C20124.66 (19)
Cl2—C8—Cl1110.00 (12)C22—C21—C20119.54 (18)
C7—C8—H8109.9C21—C22—C23120.75 (19)
Cl2—C8—H8109.9C21—C22—H22119.6
Cl1—C8—H8109.9C23—C22—H22119.6
C14—C9—C10117.29 (17)C22—C23—C18120.72 (19)
C14—C9—C2126.23 (17)C22—C23—H23119.6
C10—C9—C2116.48 (16)C18—C23—H23119.6
C11—C10—C9121.84 (18)O4—C24—H24A109.5
C11—C10—H10119.1O4—C24—H24B109.5
C9—C10—H10119.1H24A—C24—H24B109.5
C10—C11—C12120.10 (19)O4—C24—H24C109.5
C10—C11—H11120.0H24A—C24—H24C109.5
C12—C11—H11120.0H24B—C24—H24C109.5
O2—C12—C13124.98 (18)
C7—N1—C2—C9−104.12 (18)N1—C2—C9—C14−110.8 (2)
C6—N1—C2—C984.47 (19)C3—C2—C9—C1417.3 (3)
C7—N1—C2—C3123.10 (17)N1—C2—C9—C1068.9 (2)
C6—N1—C2—C3−48.31 (19)C3—C2—C9—C10−163.05 (18)
N1—C2—C3—C460.4 (2)C14—C9—C10—C110.1 (3)
C9—C2—C3—C4−67.6 (2)C2—C9—C10—C11−179.62 (18)
N1—C2—C3—C17−174.47 (15)C9—C10—C11—C120.4 (3)
C9—C2—C3—C1757.5 (2)C15—O2—C12—C132.6 (3)
N1—C2—C3—C16−54.8 (2)C15—O2—C12—C11−177.9 (3)
C9—C2—C3—C16177.18 (18)C10—C11—C12—O2−179.95 (18)
C17—C3—C4—O329.1 (3)C10—C11—C12—C13−0.5 (3)
C16—C3—C4—O3−89.2 (3)O2—C12—C13—C14179.43 (19)
C2—C3—C4—O3153.3 (2)C11—C12—C13—C140.0 (3)
C17—C3—C4—C5−150.11 (19)C10—C9—C14—C13−0.6 (3)
C16—C3—C4—C591.5 (2)C2—C9—C14—C13179.11 (18)
C2—C3—C4—C5−26.0 (2)C12—C13—C14—C90.5 (3)
O3—C4—C5—C6158.4 (2)N1—C6—C18—C19−160.22 (17)
C3—C4—C5—C6−22.3 (3)C5—C6—C18—C1975.1 (2)
C7—N1—C6—C1866.7 (2)N1—C6—C18—C2324.2 (3)
C2—N1—C6—C18−122.54 (17)C5—C6—C18—C23−100.5 (2)
C7—N1—C6—C5−170.53 (17)C23—C18—C19—C200.4 (3)
C2—N1—C6—C50.3 (2)C6—C18—C19—C20−175.39 (19)
C4—C5—C6—N136.3 (2)C18—C19—C20—C21−0.5 (3)
C4—C5—C6—C18162.32 (18)C24—O4—C21—C22169.2 (2)
C6—N1—C7—O1178.95 (18)C24—O4—C21—C20−11.7 (3)
C2—N1—C7—O17.9 (3)C19—C20—C21—O4−179.0 (2)
C6—N1—C7—C8−0.6 (3)C19—C20—C21—C220.0 (3)
C2—N1—C7—C8−171.63 (16)O4—C21—C22—C23179.7 (2)
O1—C7—C8—Cl249.9 (2)C20—C21—C22—C230.6 (3)
N1—C7—C8—Cl2−130.51 (17)C21—C22—C23—C18−0.7 (4)
O1—C7—C8—Cl1−69.7 (2)C19—C18—C23—C220.2 (3)
N1—C7—C8—Cl1109.92 (18)C6—C18—C23—C22175.8 (2)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C6—H6···O1i0.982.303.216 (2)155
C13—H13···O3ii0.932.583.453 (3)155
Symmetry codes: (i) −x+1/2, y−1/2, −z+1/2; (ii) −x+1, −y+1, −z+1.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C6—H6···O1i0.982.303.216 (2)155
C13—H13···O3ii0.932.583.453 (3)155
Symmetry codes: (i) −x+1/2, y−1/2, −z+1/2; (ii) −x+1, −y+1, −z+1.
Acknowledgements top

SP thanks UGC, India, for providing financial support.

references
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