Ethyl 4-[(E)-(2-hy­droxy­benzyl­idene)amino]­piperidine-1-carboxyl­ate

Fang, R.-Q.; Shan, Z.-L.; Guo, X.

doi:10.1107/S1600536811049750

organic compounds

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ISSN: 2056-9890

Volume 67| Part 12| December 2011| Page o3448

https://doi.org/10.1107/S1600536811049750

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Ethyl 4-[(E)-(2-hydroxybenzylidene)amino]piperidine-1-carboxylate

Rui-Qin Fang,^a,^b ^* Zhi-Li Shan ^a and Xing Guo ^a

^aSchool of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 610054, People's Republic of China, and ^bState Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing, 210093, People's Republic of China
^*Correspondence e-mail: fangrq@uestc.edu.cn

(Received 17 November 2011; accepted 21 November 2011; online 25 November 2011)

In the title compound, C₁₅H₂₀N₂O₃, the piperidine ring adopts a chair conformation, although the amide N atom is almost planar (bond angle sum = 359.7°). The molecule adopts an E conformation about the C=N bond, which allows for the formation of an intramolecular O—H⋯N hydrogen bond. In the crystal, molecules are linked by C—H⋯O interations, resulting in C(6) chains propagating in [010].

Related literature

For a related structure, see: Tas et al. (2007 ). For standard bond lengths, see: Allen et al. 1987).

Experimental

Crystal data

C₁₅H₂₀N₂O₃
M_r = 276.33
Monoclinic, P 2₁ /c
a = 15.732 (3) Å
b = 9.1890 (18) Å
c = 10.414 (2) Å
β = 97.24 (3)°
V = 1493.5 (5) Å³
Z = 4
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 293 K
0.28 × 0.23 × 0.22 mm

Data collection

Enraf–Nonius CAD-4 diffractometer
Absorption correction: ψ scan (North et al., 1968) T_min = 0.976, T_max = 0.981
3098 measured reflections
2922 independent reflections
1750 reflections with I > 2σ(I)
R_int = 0.032
3 standard reflections every 200 reflections intensity decay: 1%

Refinement

R[F² > 2σ(F²)] = 0.065
wR(F²) = 0.174
S = 1.09
2922 reflections
183 parameters
H-atom parameters constrained
Δρ_max = 0.21 e Å⁻³
Δρ_min = −0.16 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯N1	0.82	1.87	2.592 (3)	146
C15—H15B⋯O2ⁱ	0.96	2.56	3.475 (5)	160
Symmetry code: (i) $[-x+1, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ .

Data collection: CAD-4 Software (Enraf–Nonius, 1989 ); cell refinement: CAD-4 Software; data reduction: XCAD4 (Harms & Wocadlo, 1995 ); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536811049750/hb6521sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536811049750/hb6521Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S1600536811049750/hb6521Isup3.cdx

Supporting information file. DOI: https://doi.org/10.1107/S1600536811049750/hb6521Isup4.cml

checkCIF report

Comment top

The cystal structure of the Schiff base N-(1-ethoxycarbonyl)piperidine-4-yl)-3,5-di-t-butylsalicylaldimine, derived from ethyl 4-aminopiperidine-1-carboxylate and 3,5-di-tert-butylsalicylaldehyde, has been reported before (Tas et al., 2007). There are two tert butyl subsitituents on the 3- and 5- positons, as compared with the title compound. The molecular structure of title compound (I), Fig. 1, possesses an E configuration about C7=N1 double bond, and the bond length 1.268 (3) Å is in the normal range. (Allen et al. 1987). The C13=O2 double bond 1.208 (4) Å. The C2—O1, N2—C13 and C13—O3 single bond lengths are 1.352 (3), 1.343 (4) and 1.347 (4) Å, respectively. All these bond lengths is comparable to that observed in the reference compound. (Tas et al., 2007) The torsion angle of C9—C8—N1—C7 and C12—C8—N1—C7 is -108.8 (3) ° and 131.3 (3) °. The Rms deviation of phenyl ring is 0.0072 Å, and the Rms of six-member piperidine ring of chair conformation is 0.2282 Å. The The dihedral angle between phenyl plane and piperidine ring in title compound is 77.58 (10) °. There is an intramolecular hydrogen bond, O1—H1···N1, together with one kind of intermolecular hydrogen bond C15—H15B···O2 in the crystal structure of title compound. All these hydrogen bonds the molecule to form an extended network along b axis, Fig. 2.

Related literature top

For a related structure, see: Tas et al. (2007). For standard bond lengths, see: Allen et al. 1987).

Experimental top

The title compound was prepared by stirring a mixture of salicylaldehyde (122 mg, 1 mmol) and ethyl 4-aminopiperidine-1-carboxylate (172 mg, 1 mmol) in methanol (15 ml) for 3 h at room temperature. After keeping the solution in air for 4 d, yellow block-shaped crystals of (I) were formed. The crystals were isolated, washed three times with methanol and dried in a vacuum desiccator containing anhydrous CaCl₂.

Structure description top

For a related structure, see: Tas et al. (2007). For standard bond lengths, see: Allen et al. 1987).

Computing details top

Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: CAD-4 Software (Enraf–Nonius, 1989); data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. The structure of the title compound (I) showing 35% probability displacement ellipsoids.
	Fig. 2. The crystal packing of (I), viewed along the b axis. Hydrogen bonds are shown as dashed lines.

Ethyl 4-[(E)-(2-hydroxybenzylidene)amino]piperidine-1-carboxylate top

Crystal data top

C₁₅H₂₀N₂O₃	F(000) = 592
M_r = 276.33	D_x = 1.229 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 1428 reflections
a = 15.732 (3) Å	θ = 2.5–24.2°
b = 9.1890 (18) Å	µ = 0.09 mm⁻¹
c = 10.414 (2) Å	T = 293 K
β = 97.24 (3)°	Block, yellow
V = 1493.5 (5) Å³	0.28 × 0.23 × 0.22 mm
Z = 4

Data collection top

Enraf–Nonius CAD-4 diffractometer	1750 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.032
Graphite monochromator	θ_max = 26.0°, θ_min = 1.3°
ω/2θ scan	h = −19→19
Absorption correction: ψ scan (North et al., 1968)	k = −11→0
T_min = 0.976, T_max = 0.981	l = 0→12
3098 measured reflections	3 standard reflections every 200 reflections
2922 independent reflections	intensity decay: 1%

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)] = 0.065	H-atom parameters constrained
wR(F²) = 0.174	w = 1/[σ²(F_o²) + (0.0611P)² + 0.6373P] where P = (F_o² + 2F_c²)/3
S = 1.09	(Δ/σ)_max < 0.001
2922 reflections	Δρ_max = 0.21 e Å⁻³
183 parameters	Δρ_min = −0.16 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.022 (3)

Crystal data top

C₁₅H₂₀N₂O₃	V = 1493.5 (5) Å³
M_r = 276.33	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 15.732 (3) Å	µ = 0.09 mm⁻¹
b = 9.1890 (18) Å	T = 293 K
c = 10.414 (2) Å	0.28 × 0.23 × 0.22 mm
β = 97.24 (3)°

Data collection top

Enraf–Nonius CAD-4 diffractometer	1750 reflections with I > 2σ(I)
Absorption correction: ψ scan (North et al., 1968)	R_int = 0.032
T_min = 0.976, T_max = 0.981	3 standard reflections every 200 reflections
3098 measured reflections	intensity decay: 1%
2922 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.065	0 restraints
wR(F²) = 0.174	H-atom parameters constrained
S = 1.09	Δρ_max = 0.21 e Å⁻³
2922 reflections	Δρ_min = −0.16 e Å⁻³
183 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	−0.07284 (18)	0.1352 (3)	0.1715 (3)	0.0491 (7)
C2	−0.11096 (19)	0.0759 (3)	0.2735 (3)	0.0503 (7)
C3	−0.19939 (19)	0.0618 (3)	0.2628 (3)	0.0619 (8)
H3	−0.2248	0.0232	0.3312	0.074*
C4	−0.2494 (2)	0.1047 (4)	0.1517 (3)	0.0632 (9)
H4	−0.3087	0.0962	0.1460	0.076*
C5	−0.2130 (2)	0.1602 (4)	0.0488 (3)	0.0661 (9)
H5	−0.2471	0.1874	−0.0268	0.079*
C6	−0.1251 (2)	0.1749 (4)	0.0594 (3)	0.0624 (8)
H6	−0.1003	0.2124	−0.0100	0.075*
C7	0.01943 (18)	0.1592 (3)	0.1838 (3)	0.0515 (7)
H7	0.0431	0.2014	0.1153	0.062*
C8	0.16035 (17)	0.1521 (3)	0.2946 (3)	0.0526 (7)
H8	0.1725	0.2147	0.2228	0.063*
C9	0.2061 (2)	0.0066 (4)	0.2873 (3)	0.0645 (9)
H9A	0.1913	−0.0348	0.2017	0.077*
H9B	0.1865	−0.0601	0.3496	0.077*
C10	0.3033 (2)	0.0227 (4)	0.3151 (3)	0.0677 (9)
H10A	0.3300	−0.0725	0.3170	0.081*
H10B	0.3242	0.0792	0.2469	0.081*
C11	0.2866 (2)	0.2392 (4)	0.4458 (3)	0.0680 (9)
H11A	0.3062	0.3029	0.3813	0.082*
H11B	0.3038	0.2814	0.5305	0.082*
C12	0.18953 (18)	0.2265 (3)	0.4225 (3)	0.0557 (8)
H12A	0.1697	0.1713	0.4923	0.067*
H12B	0.1644	0.3229	0.4224	0.067*
C13	0.37125 (18)	0.0361 (4)	0.5437 (3)	0.0584 (8)
C14	0.4508 (2)	−0.1707 (5)	0.6252 (4)	0.0828 (11)
H14A	0.4184	−0.1817	0.6980	0.099*
H14B	0.5018	−0.1140	0.6531	0.099*
C15	0.4747 (3)	−0.3153 (5)	0.5780 (5)	0.1084 (15)
H15A	0.4240	−0.3724	0.5553	0.163*
H15B	0.5117	−0.3639	0.6449	0.163*
H15C	0.5040	−0.3031	0.5032	0.163*
N1	0.06833 (14)	0.1243 (3)	0.2853 (2)	0.0528 (6)
N2	0.32588 (16)	0.0948 (3)	0.4385 (2)	0.0626 (7)
O1	−0.06447 (13)	0.0300 (2)	0.38413 (19)	0.0671 (6)
H1	−0.0133	0.0389	0.3780	0.101*
O2	0.38554 (15)	0.0953 (3)	0.6478 (2)	0.0837 (8)
O3	0.39911 (13)	−0.0984 (3)	0.5189 (2)	0.0702 (7)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0515 (17)	0.0451 (16)	0.0500 (17)	0.0037 (13)	0.0037 (13)	0.0011 (13)
C2	0.0551 (18)	0.0422 (16)	0.0534 (17)	0.0012 (13)	0.0065 (14)	−0.0017 (14)
C3	0.0563 (19)	0.061 (2)	0.070 (2)	−0.0036 (15)	0.0119 (16)	−0.0025 (17)
C4	0.0478 (17)	0.064 (2)	0.078 (2)	0.0019 (15)	0.0065 (17)	−0.0118 (18)
C5	0.059 (2)	0.069 (2)	0.066 (2)	0.0056 (17)	−0.0080 (17)	−0.0065 (17)
C6	0.063 (2)	0.070 (2)	0.0534 (18)	0.0038 (16)	0.0041 (15)	0.0062 (16)
C7	0.0537 (17)	0.0496 (17)	0.0518 (17)	−0.0005 (14)	0.0089 (14)	0.0064 (14)
C8	0.0487 (16)	0.0589 (18)	0.0506 (17)	0.0013 (14)	0.0076 (13)	0.0110 (14)
C9	0.063 (2)	0.071 (2)	0.0567 (18)	0.0102 (16)	−0.0036 (15)	−0.0106 (16)
C10	0.065 (2)	0.079 (2)	0.0577 (19)	0.0233 (18)	0.0004 (16)	0.0001 (17)
C11	0.059 (2)	0.062 (2)	0.080 (2)	−0.0032 (16)	−0.0050 (17)	−0.0067 (18)
C12	0.0566 (18)	0.0505 (17)	0.0603 (18)	0.0047 (14)	0.0087 (14)	0.0013 (15)
C13	0.0370 (15)	0.077 (2)	0.060 (2)	−0.0037 (15)	0.0008 (14)	0.0034 (18)
C14	0.060 (2)	0.105 (3)	0.079 (2)	0.005 (2)	−0.0110 (18)	0.025 (2)
C15	0.080 (3)	0.099 (3)	0.135 (4)	0.015 (2)	−0.029 (3)	0.034 (3)
N1	0.0464 (14)	0.0562 (15)	0.0551 (15)	0.0019 (11)	0.0036 (11)	0.0084 (12)
N2	0.0598 (16)	0.0654 (17)	0.0588 (16)	0.0088 (13)	−0.0075 (12)	−0.0021 (14)
O1	0.0574 (13)	0.0852 (16)	0.0590 (13)	−0.0027 (11)	0.0085 (10)	0.0187 (12)
O2	0.0713 (16)	0.113 (2)	0.0625 (15)	−0.0005 (14)	−0.0089 (12)	−0.0106 (15)
O3	0.0568 (13)	0.0798 (16)	0.0697 (14)	0.0101 (12)	−0.0085 (11)	0.0118 (12)

Geometric parameters (Å, º) top

C1—C6	1.389 (4)	C10—N2	1.450 (4)
C1—C2	1.394 (4)	C10—H10A	0.9700
C1—C7	1.458 (4)	C10—H10B	0.9700
C2—O1	1.352 (3)	C11—N2	1.470 (4)
C2—C3	1.388 (4)	C11—C12	1.520 (4)
C3—C4	1.373 (4)	C11—H11A	0.9700
C3—H3	0.9300	C11—H11B	0.9700
C4—C5	1.375 (4)	C12—H12A	0.9700
C4—H4	0.9300	C12—H12B	0.9700
C5—C6	1.380 (4)	C13—O2	1.208 (4)
C5—H5	0.9300	C13—N2	1.343 (4)
C6—H6	0.9300	C13—O3	1.347 (4)
C7—N1	1.268 (3)	C14—O3	1.449 (4)
C7—H7	0.9300	C14—C15	1.482 (6)
C8—N1	1.461 (3)	C14—H14A	0.9700
C8—C12	1.516 (4)	C14—H14B	0.9700
C8—C9	1.525 (4)	C15—H15A	0.9600
C8—H8	0.9800	C15—H15B	0.9600
C9—C10	1.527 (4)	C15—H15C	0.9600
C9—H9A	0.9700	O1—H1	0.8200
C9—H9B	0.9700

C6—C1—C2	118.5 (3)	N2—C10—H10B	109.7
C6—C1—C7	120.7 (3)	C9—C10—H10B	109.7
C2—C1—C7	120.8 (3)	H10A—C10—H10B	108.2
O1—C2—C3	117.9 (3)	N2—C11—C12	110.1 (3)
O1—C2—C1	122.2 (3)	N2—C11—H11A	109.6
C3—C2—C1	119.9 (3)	C12—C11—H11A	109.6
C4—C3—C2	120.2 (3)	N2—C11—H11B	109.6
C4—C3—H3	119.9	C12—C11—H11B	109.6
C2—C3—H3	119.9	H11A—C11—H11B	108.2
C3—C4—C5	120.8 (3)	C8—C12—C11	111.2 (2)
C3—C4—H4	119.6	C8—C12—H12A	109.4
C5—C4—H4	119.6	C11—C12—H12A	109.4
C4—C5—C6	119.1 (3)	C8—C12—H12B	109.4
C4—C5—H5	120.5	C11—C12—H12B	109.4
C6—C5—H5	120.5	H12A—C12—H12B	108.0
C5—C6—C1	121.5 (3)	O2—C13—N2	124.8 (3)
C5—C6—H6	119.3	O2—C13—O3	123.8 (3)
C1—C6—H6	119.3	N2—C13—O3	111.3 (3)
N1—C7—C1	121.8 (3)	O3—C14—C15	107.4 (3)
N1—C7—H7	119.1	O3—C14—H14A	110.2
C1—C7—H7	119.1	C15—C14—H14A	110.2
N1—C8—C12	108.9 (2)	O3—C14—H14B	110.2
N1—C8—C9	108.2 (2)	C15—C14—H14B	110.2
C12—C8—C9	110.3 (2)	H14A—C14—H14B	108.5
N1—C8—H8	109.8	C14—C15—H15A	109.5
C12—C8—H8	109.8	C14—C15—H15B	109.5
C9—C8—H8	109.8	H15A—C15—H15B	109.5
C8—C9—C10	111.9 (3)	C14—C15—H15C	109.5
C8—C9—H9A	109.2	H15A—C15—H15C	109.5
C10—C9—H9A	109.2	H15B—C15—H15C	109.5
C8—C9—H9B	109.2	C7—N1—C8	120.2 (2)
C10—C9—H9B	109.2	C13—N2—C10	125.9 (3)
H9A—C9—H9B	107.9	C13—N2—C11	120.3 (3)
N2—C10—C9	109.9 (3)	C10—N2—C11	113.6 (2)
N2—C10—H10A	109.7	C2—O1—H1	109.5
C9—C10—H10A	109.7	C13—O3—C14	116.0 (3)

C6—C1—C2—O1	177.8 (3)	C9—C8—C12—C11	53.5 (3)
C7—C1—C2—O1	−4.2 (4)	N2—C11—C12—C8	−55.7 (4)
C6—C1—C2—C3	−1.9 (4)	C1—C7—N1—C8	−179.1 (3)
C7—C1—C2—C3	176.2 (3)	C12—C8—N1—C7	131.3 (3)
O1—C2—C3—C4	−179.0 (3)	C9—C8—N1—C7	−108.8 (3)
C1—C2—C3—C4	0.6 (4)	O2—C13—N2—C10	−175.8 (3)
C2—C3—C4—C5	0.9 (5)	O3—C13—N2—C10	4.1 (4)
C3—C4—C5—C6	−1.2 (5)	O2—C13—N2—C11	−2.3 (5)
C4—C5—C6—C1	0.0 (5)	O3—C13—N2—C11	177.6 (3)
C2—C1—C6—C5	1.6 (5)	C9—C10—N2—C13	115.9 (3)
C7—C1—C6—C5	−176.5 (3)	C9—C10—N2—C11	−58.0 (4)
C6—C1—C7—N1	179.7 (3)	C12—C11—N2—C13	−115.3 (3)
C2—C1—C7—N1	1.8 (4)	C12—C11—N2—C10	59.0 (4)
N1—C8—C9—C10	−172.0 (2)	O2—C13—O3—C14	−1.6 (4)
C12—C8—C9—C10	−53.0 (3)	N2—C13—O3—C14	178.5 (3)
C8—C9—C10—N2	54.5 (4)	C15—C14—O3—C13	−179.8 (3)
N1—C8—C12—C11	172.1 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1	0.82	1.87	2.592 (3)	146
C15—H15B···O2ⁱ	0.96	2.56	3.475 (5)	160

Symmetry code: (i) −x+1, y−1/2, −z+3/2.

Experimental details

Crystal data
Chemical formula	C₁₅H₂₀N₂O₃
M_r	276.33
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	15.732 (3), 9.1890 (18), 10.414 (2)
β (°)	97.24 (3)
V (Å³)	1493.5 (5)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.28 × 0.23 × 0.22

Data collection
Diffractometer	Enraf–Nonius CAD-4
Absorption correction	ψ scan (North et al., 1968)
T_min, T_max	0.976, 0.981
No. of measured, independent and observed [I > 2σ(I)] reflections	3098, 2922, 1750
R_int	0.032
(sin θ/λ)_max (Å⁻¹)	0.616

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.065, 0.174, 1.09
No. of reflections	2922
No. of parameters	183
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.21, −0.16

Computer programs: CAD-4 Software (Enraf–Nonius, 1989), XCAD4 (Harms & Wocadlo, 1995), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1	0.82	1.87	2.592 (3)	146
C15—H15B···O2ⁱ	0.96	2.56	3.475 (5)	160

Symmetry code: (i) −x+1, y−1/2, −z+3/2.

Acknowledgements

We are grateful to the Fundamental Research Funds for the Central Universities (ZYGX2009J085) and the China Postdoctoral Science Foundation (20110491380) for support.

References

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