Crystal structure of 2,2-di­chloro-1-(piperidin-1-yl)ethanone

Abstract

In the title compound, C₇H₁₁Cl₂NO, the piperidine ring shows a chair conformation and the bond-angle sum at the N atom is 359.9°. The H atom of the di­chloro­methyl group is in an eclipsed conformation with respect to the carbonyl group (H—C—C=O = −5°). In the crystal, inversion dimers are linked by pairs of C—H⋯O hydrogen bonds between the di­chloro­methyl group and the carbonyl O atom, which generate R ₂ ²(8) loops. The dimers are linked into a ladder-like structure propagating in the [100] direction by short O⋯Cl [3.1084 (9) Å] contacts.

Related literature  

For the synthetic procedure, see: Schank (1967 ▸). For a survey concerning weak hydrogen bonds, see: Desiraju & Steiner (1999 ▸). For a description of the nature of inter­molecular inter­actions between chlorine and oxygen, see: Lommerse et al. (1996 ▸). For the crystal structure of the starting compound, see: Schwierz et al. (2015 ▸).

Experimental  

Crystal data  

• C₇H₁₁Cl₂NO

• M _r = 196.07

• Monoclinic,

• a = 6.2972 (1) Å

• b = 15.4896 (2) Å

• c = 9.3709 (2) Å

• β = 108.920 (1)°

• V = 864.66 (3) ų

• Z = 4

• Mo Kα radiation

• μ = 0.69 mm⁻¹

• T = 133 K

• 0.08 × 0.07 × 0.06 mm

Data collection  

• Nonius KappaCCD diffractometer

• Absorption correction: multi-scan (SADABS; Bruker, 2002 ▸) T _min = 0.712, T _max = 0.746

• 5528 measured reflections

• 1982 independent reflections

• 1909 reflections with I > 2σ(I)

• R _int = 0.014

Refinement  

• R[F ² > 2σ(F ²)] = 0.020

• wR(F ²) = 0.051

• S = 1.07

• 1982 reflections

• 144 parameters

• All H-atom parameters refined

• Δρ_max = 0.36 e Å⁻³

• Δρ_min = −0.18 e Å⁻³

Data collection: COLLECT (Nonius, 1998 ▸); cell refinement: DENZO (Otwinowski & Minor, 1997 ▸); data reduction: DENZO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▸); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▸); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012 ▸) and Mercury (Macrae et al., 2008 ▸); software used to prepare material for publication: SHELXL97.

Supplementary Material

CCDC reference: 1038542

Additional supporting information: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (, ).

DHA	DH	HA	D A	DHA
C7H7O1i	0.927(13)	2.286(12)	3.1931(13)	166(1)

Symmetry code: (i) .

supplementary crystallographic information

S1. Comment

The title compound is an intermediate in the synthesis of 2,2-dimethoxy-1-(pyridin-2-yl)ethanone and has been synthesized from 2,2-dichloro-1-(piperidin-1-yl)butane-1,3-dione (Schwierz et al., 2015) following a modified procedure (Schank, 1967). As it is expected the piperidine ring shows a chair conformation and the amide substructure is planar. The hydrogen atom of the dichloromethyl group is in an eclipsed conformation with respect to the carbonyl group. In the crystal structure, dimeric aggregates are formed by hydrogen bonds of the C–H···O type between the dichloromethyl group and the carbonyl oxygen atom. In addition, these dimers are linked into a ladder-like structure parallel to the ac plane by oxygen chlorine contacts.

S2. Experimental

22 ml methanol was cooled down to -6°C and then 1.93 g (84 mmol) sodium was slowly added in a way that the temperature is maintained. Afterwards 20.0 g (84 mmol) 2,2-dichloro-1-(piperidin-1-yl)butane-1,3-dione in 10 ml methanol was dropwise added to the solution of NaOMe. The resulting solution was stirred for 30 minutes and then neutralized with aqueous HCl at -10°C. After evaporating the mixture to dryness the amorphous material was collected on filter paper in a Büchner funnel and washed with water (yield: 13.6 g, 83%). The product has to be destilled in vacuo (0.2 mbar) and condensed into a Schlenk tube cooled by liquid nitrogen to obtain colourless prisms for X-ray diffraction.

S3. Refinement

The positions of all hydrogen atoms have been determined from a Fourier map and all hydrogen atoms were refined without any constraints.

Figures

Fig. 1.

: Molecular structure of the title compound with displacement ellipsoids drawn at the 50% probability level.

Fig. 2.

: Crystal structure of the title compound showing ladder-like arrangement parallel to the ac plane.

Crystal data

C7H11Cl2NO	Z = 4
Mr = 196.07	F(000) = 408
Monoclinic, P21/n	Dx = 1.506 Mg m−3
Hall symbol: -P 2yn	Mo Kα radiation, λ = 0.71073 Å
a = 6.2972 (1) Å	µ = 0.69 mm−1
b = 15.4896 (2) Å	T = 133 K
c = 9.3709 (2) Å	Prism, colourless
β = 108.920 (1)°	0.08 × 0.07 × 0.06 mm
V = 864.66 (3) Å3

Data collection

Nonius KappaCCD diffractometer	1982 independent reflections
Radiation source: fine-focus sealed tube	1909 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.014
phi– + ω–scan	θmax = 27.5°, θmin = 2.6°
Absorption correction: multi-scan (SADABS; Bruker, 2002)	h = −8→8
Tmin = 0.712, Tmax = 0.746	k = −17→20
5528 measured reflections	l = −12→8

Refinement

Refinement on F2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.020	Hydrogen site location: difference Fourier map
wR(F2) = 0.051	All H-atom parameters refined
S = 1.07	w = 1/[σ2(Fo2) + (0.0187P)2 + 0.3796P] where P = (Fo2 + 2Fc2)/3
1982 reflections	(Δ/σ)max = 0.001
144 parameters	Δρmax = 0.36 e Å−3
0 restraints	Δρmin = −0.18 e Å−3

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 (Ų)

	x	y	z	Uiso*/Ueq
Cl1	0.58896 (4)	0.397515 (17)	0.60904 (3)	0.01933 (8)
Cl2	1.00866 (4)	0.453542 (17)	0.83711 (3)	0.01976 (8)
O1	1.06874 (14)	0.38479 (5)	0.48067 (9)	0.02086 (18)
N1	1.05601 (15)	0.28336 (6)	0.65192 (10)	0.01611 (18)
C1	1.20371 (19)	0.22440 (7)	0.60412 (13)	0.0191 (2)
H1B	1.333 (2)	0.2132 (9)	0.6929 (16)	0.023 (3)*
H1A	1.254 (2)	0.2541 (9)	0.5296 (16)	0.021 (3)*
C2	1.0825 (2)	0.14060 (7)	0.54290 (13)	0.0187 (2)
H2B	0.959 (2)	0.1519 (9)	0.4527 (17)	0.023 (3)*
H2A	1.189 (2)	0.1027 (9)	0.5171 (17)	0.026 (4)*
C3	0.99241 (19)	0.09891 (7)	0.65911 (13)	0.0185 (2)
H3B	0.910 (2)	0.0471 (9)	0.6184 (15)	0.019 (3)*
H3A	1.119 (2)	0.0834 (9)	0.7476 (16)	0.022 (3)*
C4	0.84334 (18)	0.16225 (7)	0.70759 (12)	0.0170 (2)
H4B	0.713 (2)	0.1755 (9)	0.6231 (15)	0.019 (3)*
H4A	0.792 (2)	0.1379 (9)	0.7849 (16)	0.022 (3)*
C5	0.96872 (19)	0.24606 (7)	0.76638 (12)	0.0167 (2)
H5B	1.098 (2)	0.2349 (9)	0.8562 (15)	0.018 (3)*
H5A	0.875 (2)	0.2867 (9)	0.7911 (15)	0.018 (3)*
C6	1.00703 (17)	0.36088 (7)	0.58641 (11)	0.0140 (2)
C7	0.87376 (17)	0.42766 (7)	0.64343 (11)	0.0141 (2)
H7	0.874 (2)	0.4785 (8)	0.5911 (14)	0.013 (3)*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Cl1	0.01372 (13)	0.02241 (14)	0.02175 (14)	−0.00113 (10)	0.00559 (10)	−0.00364 (10)
Cl2	0.02030 (14)	0.01973 (14)	0.01757 (13)	−0.00162 (10)	0.00382 (10)	−0.00656 (9)
O1	0.0272 (4)	0.0187 (4)	0.0225 (4)	0.0016 (3)	0.0162 (3)	0.0043 (3)
N1	0.0203 (4)	0.0119 (4)	0.0204 (4)	0.0008 (3)	0.0126 (4)	0.0009 (3)
C1	0.0189 (5)	0.0149 (5)	0.0278 (6)	0.0014 (4)	0.0136 (5)	0.0003 (4)
C2	0.0213 (5)	0.0154 (5)	0.0218 (5)	0.0021 (4)	0.0103 (4)	−0.0008 (4)
C3	0.0214 (5)	0.0125 (5)	0.0214 (5)	−0.0016 (4)	0.0065 (4)	0.0003 (4)
C4	0.0181 (5)	0.0167 (5)	0.0173 (5)	−0.0017 (4)	0.0071 (4)	0.0027 (4)
C5	0.0226 (5)	0.0142 (5)	0.0160 (5)	0.0003 (4)	0.0101 (4)	0.0020 (4)
C6	0.0137 (5)	0.0138 (5)	0.0152 (5)	−0.0025 (4)	0.0054 (4)	−0.0012 (4)
C7	0.0150 (5)	0.0136 (5)	0.0146 (5)	−0.0014 (4)	0.0057 (4)	−0.0004 (4)

Geometric parameters (Å, º)

Cl1—C7	1.7786 (10)	C2—H2A	0.977 (15)
Cl2—C7	1.7823 (10)	C3—C4	1.5254 (15)
O1—C6	1.2328 (13)	C3—H3B	0.966 (14)
N1—C6	1.3383 (14)	C3—H3A	0.974 (15)
N1—C5	1.4726 (13)	C4—C5	1.5264 (15)
N1—C1	1.4731 (13)	C4—H4B	0.961 (14)
C1—C2	1.5208 (15)	C4—H4A	0.961 (14)
C1—H1B	0.973 (15)	C5—H5B	0.980 (14)
C1—H1A	0.971 (14)	C5—H5A	0.942 (14)
C2—C3	1.5249 (15)	C6—C7	1.5332 (14)
C2—H2B	0.960 (15)	C7—H7	0.927 (13)
C6—N1—C5	126.95 (9)	C3—C4—C5	110.99 (9)
C6—N1—C1	119.41 (9)	C3—C4—H4B	109.7 (8)
C5—N1—C1	113.57 (8)	C5—C4—H4B	108.7 (8)
N1—C1—C2	110.77 (9)	C3—C4—H4A	111.2 (8)
N1—C1—H1B	106.7 (8)	C5—C4—H4A	108.9 (8)
C2—C1—H1B	110.4 (8)	H4B—C4—H4A	107.2 (11)
N1—C1—H1A	108.1 (8)	N1—C5—C4	110.02 (9)
C2—C1—H1A	112.0 (8)	N1—C5—H5B	106.9 (8)
H1B—C1—H1A	108.8 (12)	C4—C5—H5B	110.5 (8)
C1—C2—C3	110.46 (9)	N1—C5—H5A	109.2 (8)
C1—C2—H2B	109.9 (9)	C4—C5—H5A	111.4 (8)
C3—C2—H2B	109.0 (8)	H5B—C5—H5A	108.8 (11)
C1—C2—H2A	107.8 (8)	O1—C6—N1	123.54 (10)
C3—C2—H2A	111.4 (8)	O1—C6—C7	115.35 (9)
H2B—C2—H2A	108.3 (12)	N1—C6—C7	121.09 (9)
C2—C3—C4	110.35 (9)	C6—C7—Cl1	113.17 (7)
C2—C3—H3B	110.4 (8)	C6—C7—Cl2	111.88 (7)
C4—C3—H3B	110.3 (8)	Cl1—C7—Cl2	111.30 (5)
C2—C3—H3A	108.8 (8)	C6—C7—H7	107.1 (8)
C4—C3—H3A	108.4 (8)	Cl1—C7—H7	107.6 (8)
H3B—C3—H3A	108.6 (11)	Cl2—C7—H7	105.4 (8)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C7—H7···O1i	0.927 (13)	2.286 (12)	3.1931 (13)	166 (1)

Symmetry code: (i) −x+2, −y+1, −z+1.