1-Methyl-5-(4-methyl­phen­yl)-3-oxo­cyclo­hexane-1-carbonitrile

Mohan, R.T.S.; Kamatchi, S.; Subramanyam, M.; Thiruvalluvar, A.; Linden, A.

doi:10.1107/S1600536808009070

organic compounds

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ISSN: 2056-9890

Volume 64| Part 5| May 2008| Page o818

doi:10.1107/S1600536808009070

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1-Methyl-5-(4-methylphenyl)-3-oxocyclohexane-1-carbonitrile

R. T. Sabapathy Mohan,^a S. Kamatchi,^a M. Subramanyam,^b A. Thiruvalluvar ^b ^* and A. Linden ^c

^aDepartment of Chemistry, Annamalai University, Annamalai Nagar 608 002, Tamil Nadu, India, ^bPG Research Department of Physics, Rajah Serfoji Government College (Autonomous), Thanjavur 613 005, Tamil Nadu, India, and ^cInstitute of Organic Chemistry, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
^*Correspondence e-mail: athiru@vsnl.net

(Received 1 April 2008; accepted 3 April 2008; online 10 April 2008)

In the title molecule, C₁₅H₁₇NO, the cyclohexane ring adopts a chair conformation. The cyano and methyl groups at position 1 have axial and equatorial orientations, respectively. The benzene ring has an equatorial orientation. A C—H⋯π interaction involving the benzene ring is found in the crystal structure.

Related literature

Subramanyam et al. (2007 ) have reported the crystal structure of 3-cyano-3-methyl-5-phenylcyclohexane, in which the cyclohexane ring adopts a chair conformation.

Experimental

Crystal data

C₁₅H₁₇NO
M_r = 227.30
Monoclinic, C 2/c
a = 23.4475 (5) Å
b = 6.0370 (1) Å
c = 21.0740 (5) Å
β = 123.267 (1)°
V = 2494.22 (9) Å³
Z = 8
Mo Kα radiation
μ = 0.07 mm⁻¹
T = 160 (1) K
0.25 × 0.20 × 0.10 mm

Data collection

Nonius KappaCCD area-detector diffractometer
Absorption correction: none
37687 measured reflections
3640 independent reflections
2682 reflections with I > 2σ(I)
R_int = 0.054

Refinement

R[F² > 2σ(F²)] = 0.052
wR(F²) = 0.170
S = 1.08
3640 reflections
154 parameters
H-atom parameters constrained
Δρ_max = 0.42 e Å⁻³
Δρ_min = −0.27 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C4—H4A⋯Cgⁱ	0.99	2.61	3.5425 (15)	157
Symmetry code: (i) $[-x, y, -z+{\script{1\over 2}}]$ . Cg is the centroid of the benzene ring.

Data collection: COLLECT (Nonius, 2000 ); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997 ); data reduction: DENZO-SMN and SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997 ); software used to prepare material for publication: PLATON (Spek, 2003 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808009070/wn2249sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808009070/wn2249Isup2.hkl

checkCIF report

Comment top

The title compound has been analysed as part of our crystallographic studies on substituted cyclohexanes (Subramanyam et al., 2007). Its molecular structure, with atomic numbering scheme, is shown in Fig. 1. The cyclohexane ring adopts a chair conformation. The cyano group and the methyl group at position 1 have axial and equatorial orientations respectively. The benzene ring at position 5 has an equatorial orientation. A C4—H4A···π(-x, y, 1/2 - z) interaction involving the benzene ring is found in the structure. No classical hydrogen bonds are found in the crystal structure.

Related literature top

Subramanyam et al. (2007) have reported the crystal structure of 3-cyano-3-methyl-5-phenylcyclohexane, in which the cyclohexane ring adopts a chair conformation.

Experimental top

A mixture of 5-4'-methylphenyl-3-methylcyclohex-2-enone (4.00 g, 0.02 mol), potassium cyanide (2.60 g, 0.04 mol), ammonium chloride (1.59 g, 0.03 mol), dimethylformamide (50 ml) and water (2 ml) was heated with stirring for 16-18 h at 353 K. The reaction mixture was cooled to room temperature and poured into water. The product was extracted with CH₂Cl₂ (3x10 ml) and the organic layer was dried, evaporated and purified by column chromatography (hexane-EtOAc, 4.5:1 v/v). The yield of the isolated product was 3.40 g (75%).

Computing details top

Data collection: COLLECT (Nonius, 2000); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997); data reduction: DENZO-SMN and SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: PLATON (Spek, 2003).

Figures top

Fig. 1. The molecular structure of the title compound, showing the atom-numbering scheme and displacement ellipsoids drawn at the 50% probability level. Hydrogen atoms are represented by spheres of arbitrary radius.

1-Methyl-5-(4-methylphenyl)-3-oxocyclohexane-1-carbonitrile top

Crystal data top

C₁₅H₁₇NO	F(000) = 976
M_r = 227.30	D_x = 1.211 Mg m⁻³
Monoclinic, C2/c	Melting point: 376 K
Hall symbol: -C 2yc	Mo Kα radiation, λ = 0.71073 Å
a = 23.4475 (5) Å	Cell parameters from 3933 reflections
b = 6.0370 (1) Å	θ = 2.0–30.0°
c = 21.0740 (5) Å	µ = 0.08 mm⁻¹
β = 123.267 (1)°	T = 160 K
V = 2494.22 (9) Å³	Tablet, colourless
Z = 8	0.25 × 0.20 × 0.10 mm

Data collection top

Nonius KappaCCD area-detector diffractometer	2682 reflections with I > 2σ(I)
Radiation source: Nonius FR590 sealed tube generator	R_int = 0.054
Horizontally mounted graphite crystal monochromator	θ_max = 30.1°, θ_min = 2.1°
Detector resolution: 9 pixels mm^-1	h = 0→32
ϕ and ω scans with κ offsets	k = 0→8
37687 measured reflections	l = −29→24
3640 independent reflections

Refinement top

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)] = 0.052	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.170	H-atom parameters constrained
S = 1.08	w = 1/[σ²(F_o²) + (0.0889P)² + 1.0674P] where P = (F_o² + 2F_c²)/3
3640 reflections	(Δ/σ)_max < 0.001
154 parameters	Δρ_max = 0.42 e Å⁻³
0 restraints	Δρ_min = −0.27 e Å⁻³

Crystal data top

C₁₅H₁₇NO	V = 2494.22 (9) Å³
M_r = 227.30	Z = 8
Monoclinic, C2/c	Mo Kα radiation
a = 23.4475 (5) Å	µ = 0.08 mm⁻¹
b = 6.0370 (1) Å	T = 160 K
c = 21.0740 (5) Å	0.25 × 0.20 × 0.10 mm
β = 123.267 (1)°

Data collection top

Nonius KappaCCD area-detector diffractometer	2682 reflections with I > 2σ(I)
37687 measured reflections	R_int = 0.054
3640 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.052	0 restraints
wR(F²) = 0.170	H-atom parameters constrained
S = 1.08	Δρ_max = 0.42 e Å⁻³
3640 reflections	Δρ_min = −0.27 e Å⁻³
154 parameters

Special details top

Experimental. Solvent used: ? Cooling Device: Oxford Cryosystems Cryostream 700 Crystal mount: glued on a glass fibre Mosaicity (°.): 0.608 (1) Frames collected: 469 Seconds exposure per frame: 68 Degrees rotation per frame: 1.7 Crystal-Detector distance (mm): 30.0

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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
O3	−0.15528 (6)	0.46344 (19)	0.25177 (7)	0.0415 (4)
N12	−0.08326 (7)	0.6151 (2)	0.47679 (8)	0.0396 (4)
C1	−0.11894 (7)	0.9214 (2)	0.37288 (8)	0.0257 (4)
C2	−0.16638 (7)	0.8175 (3)	0.29352 (8)	0.0301 (4)
C3	−0.13059 (7)	0.6453 (2)	0.27576 (7)	0.0284 (4)
C4	−0.06263 (7)	0.7130 (2)	0.28980 (8)	0.0285 (4)
C5	−0.01555 (6)	0.8211 (2)	0.36851 (7)	0.0235 (3)
C6	−0.05364 (7)	1.0065 (2)	0.37989 (8)	0.0257 (4)
C11	−0.15578 (8)	1.1085 (3)	0.38596 (10)	0.0358 (5)
C12	−0.09953 (7)	0.7479 (2)	0.43103 (8)	0.0283 (4)
C15	0.24199 (7)	1.0891 (3)	0.40745 (9)	0.0366 (5)
C51	0.05077 (6)	0.8959 (2)	0.37806 (7)	0.0234 (3)
C52	0.10525 (7)	0.7488 (2)	0.40770 (7)	0.0268 (4)
C53	0.16606 (7)	0.8088 (2)	0.41545 (8)	0.0288 (4)
C54	0.17508 (7)	1.0191 (3)	0.39554 (8)	0.0283 (4)
C55	0.12020 (7)	1.1653 (2)	0.36508 (9)	0.0321 (4)
C56	0.05907 (7)	1.1049 (2)	0.35635 (9)	0.0308 (4)
H2A	−0.20592	0.74844	0.29089	0.0361*
H2B	−0.18388	0.93583	0.25469	0.0361*
H4A	−0.07029	0.81889	0.24998	0.0341*
H4B	−0.03970	0.58069	0.28600	0.0341*
H5	−0.00387	0.70502	0.40771	0.0282*
H6A	−0.06599	1.12360	0.34155	0.0308*
H6B	−0.02313	1.07305	0.43072	0.0308*
H11A	−0.16873	1.22489	0.34797	0.0537*
H11B	−0.12531	1.17052	0.43686	0.0537*
H11C	−0.19680	1.04942	0.38141	0.0537*
H15A	0.27435	0.96550	0.42915	0.0549*
H15B	0.26039	1.21551	0.44228	0.0549*
H15C	0.23475	1.13160	0.35866	0.0549*
H52	0.10086	0.60508	0.42290	0.0321*
H53	0.20209	0.70396	0.43470	0.0345*
H55	0.12464	1.30917	0.34997	0.0384*
H56	0.02242	1.20775	0.33526	0.0370*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O3	0.0412 (6)	0.0397 (6)	0.0472 (7)	−0.0142 (5)	0.0266 (5)	−0.0148 (5)
N12	0.0409 (7)	0.0425 (8)	0.0396 (7)	−0.0060 (6)	0.0248 (6)	0.0051 (6)
C1	0.0254 (6)	0.0250 (6)	0.0306 (7)	−0.0027 (5)	0.0178 (6)	−0.0022 (5)
C2	0.0233 (6)	0.0366 (8)	0.0285 (7)	−0.0015 (6)	0.0130 (5)	−0.0014 (6)
C3	0.0273 (7)	0.0332 (8)	0.0231 (7)	−0.0052 (5)	0.0129 (5)	−0.0028 (5)
C4	0.0283 (7)	0.0303 (7)	0.0304 (7)	−0.0032 (5)	0.0184 (6)	−0.0045 (5)
C5	0.0224 (6)	0.0230 (6)	0.0265 (6)	−0.0008 (5)	0.0144 (5)	0.0021 (5)
C6	0.0258 (6)	0.0246 (7)	0.0301 (7)	−0.0042 (5)	0.0176 (6)	−0.0030 (5)
C11	0.0364 (8)	0.0305 (8)	0.0515 (9)	−0.0015 (6)	0.0311 (7)	−0.0045 (7)
C12	0.0258 (6)	0.0329 (7)	0.0303 (7)	−0.0071 (5)	0.0181 (6)	−0.0048 (6)
C15	0.0275 (7)	0.0443 (9)	0.0427 (9)	−0.0070 (6)	0.0222 (7)	−0.0033 (7)
C51	0.0229 (6)	0.0248 (6)	0.0241 (6)	−0.0018 (5)	0.0140 (5)	0.0003 (5)
C52	0.0258 (6)	0.0264 (7)	0.0272 (7)	−0.0003 (5)	0.0140 (5)	0.0040 (5)
C53	0.0232 (6)	0.0332 (7)	0.0281 (7)	0.0030 (5)	0.0128 (5)	0.0034 (6)
C54	0.0249 (6)	0.0340 (7)	0.0289 (7)	−0.0052 (5)	0.0167 (6)	−0.0035 (5)
C55	0.0346 (7)	0.0252 (7)	0.0450 (9)	−0.0036 (6)	0.0273 (7)	0.0009 (6)
C56	0.0296 (7)	0.0258 (7)	0.0428 (8)	0.0033 (5)	0.0235 (7)	0.0056 (6)

Geometric parameters (Å, º) top

O3—C3	1.2145 (17)	C2—H2A	0.9900
N12—C12	1.1466 (19)	C2—H2B	0.9900
C1—C2	1.545 (2)	C4—H4A	0.9900
C1—C6	1.543 (3)	C4—H4B	0.9900
C1—C11	1.536 (3)	C5—H5	1.0000
C1—C12	1.4812 (19)	C6—H6A	0.9900
C2—C3	1.507 (2)	C6—H6B	0.9900
C3—C4	1.509 (3)	C11—H11A	0.9800
C4—C5	1.5450 (19)	C11—H11B	0.9800
C5—C6	1.531 (2)	C11—H11C	0.9800
C5—C51	1.523 (2)	C15—H15A	0.9800
C15—C54	1.507 (3)	C15—H15B	0.9800
C51—C52	1.391 (2)	C15—H15C	0.9800
C51—C56	1.3917 (18)	C52—H52	0.9500
C52—C53	1.391 (3)	C53—H53	0.9500
C53—C54	1.389 (2)	C55—H55	0.9500
C54—C55	1.393 (2)	C56—H56	0.9500
C55—C56	1.390 (3)

O3···H6Aⁱ	2.8000	H4A···C55^vii	2.9200
O3···H11Aⁱ	2.6400	H4A···C56^vii	2.9500
O3···H15Cⁱⁱ	2.8500	H4B···C52	3.1000
O3···H55ⁱⁱ	2.7700	H4B···H56ⁱ	2.5700
N12···H11Bⁱ	2.8200	H5···C12	2.5600
N12···H5ⁱⁱⁱ	2.8900	H5···H52	2.3700
N12···H6B^iv	2.8700	H5···N12ⁱⁱⁱ	2.8900
N12···H52ⁱⁱⁱ	2.7100	H6A···O3^ix	2.8000
C4···C12	3.532 (2)	H6A···C56	2.7800
C12···C4	3.532 (2)	H6A···H2B	2.5900
C12···C15^v	3.598 (3)	H6A···H11A	2.5600
C15···C12^vi	3.598 (3)	H6A···H56	2.2100
C6···H56	2.7200	H6B···C56	3.0900
C12···H5	2.5600	H6B···H11B	2.5400
C12···H6B^iv	2.9600	H6B···N12^iv	2.8700
C15···H2B^vii	3.0500	H6B···C12^iv	2.9600
C51···H4A^vii	3.0100	H11A···O3^ix	2.6400
C52···H4B	3.1000	H11A···H2B	2.5000
C52···H55ⁱ	3.0600	H11A···H6A	2.5600
C52···H4A^vii	2.9800	H11B···N12^ix	2.8200
C52···H11B^iv	3.0800	H11B···H6B	2.5400
C53···H4A^vii	2.9300	H11B···C52^iv	3.0800
C53···H53^viii	2.9700	H11C···H2A	2.5600
C54···H4A^vii	2.9400	H15A···H53	2.3700
C55···H52^ix	3.0600	H15C···O3^x	2.8500
C55···H4A^vii	2.9200	H15C···H2B^vii	2.3200
C56···H6A	2.7800	H15C···H2A^vi	2.5800
C56···H6B	3.0900	H52···C55ⁱ	3.0600
C56···H4A^vii	2.9500	H52···H5	2.3700
H2A···H11C	2.5600	H52···N12ⁱⁱⁱ	2.7100
H2A···H15C^v	2.5800	H53···H15A	2.3700
H2B···H6A	2.5900	H53···C53^viii	2.9700
H2B···H11A	2.5000	H53···H53^viii	2.4800
H2B···C15^vii	3.0500	H55···C52^ix	3.0600
H2B···H15C^vii	2.3200	H55···O3^x	2.7700
H4A···C51^vii	3.0100	H56···C6	2.7200
H4A···C52^vii	2.9800	H56···H4B^ix	2.5700
H4A···C53^vii	2.9300	H56···H6A	2.2100
H4A···C54^vii	2.9400

C2—C1—C6	109.04 (13)	C3—C4—H4B	109.00
C2—C1—C11	110.55 (14)	C5—C4—H4A	109.00
C2—C1—C12	108.69 (11)	C5—C4—H4B	109.00
C6—C1—C11	111.35 (12)	H4A—C4—H4B	108.00
C6—C1—C12	108.53 (13)	C4—C5—H5	108.00
C11—C1—C12	108.62 (14)	C6—C5—H5	108.00
C1—C2—C3	112.38 (13)	C51—C5—H5	108.00
O3—C3—C2	121.60 (17)	C1—C6—H6A	109.00
O3—C3—C4	122.51 (15)	C1—C6—H6B	109.00
C2—C3—C4	115.89 (12)	C5—C6—H6A	109.00
C3—C4—C5	112.38 (13)	C5—C6—H6B	109.00
C4—C5—C6	110.02 (12)	H6A—C6—H6B	108.00
C4—C5—C51	110.09 (12)	C1—C11—H11A	109.00
C6—C5—C51	113.81 (11)	C1—C11—H11B	109.00
C1—C6—C5	112.03 (11)	C1—C11—H11C	109.00
N12—C12—C1	178.70 (18)	H11A—C11—H11B	109.00
C5—C51—C52	119.32 (12)	H11A—C11—H11C	109.00
C5—C51—C56	122.83 (13)	H11B—C11—H11C	109.00
C52—C51—C56	117.83 (15)	C54—C15—H15A	109.00
C51—C52—C53	121.07 (12)	C54—C15—H15B	109.00
C52—C53—C54	121.23 (14)	C54—C15—H15C	109.00
C15—C54—C53	121.54 (16)	H15A—C15—H15B	109.00
C15—C54—C55	120.88 (16)	H15A—C15—H15C	109.00
C53—C54—C55	117.58 (17)	H15B—C15—H15C	109.00
C54—C55—C56	121.31 (13)	C51—C52—H52	119.00
C51—C56—C55	120.95 (14)	C53—C52—H52	119.00
C1—C2—H2A	109.00	C52—C53—H53	119.00
C1—C2—H2B	109.00	C54—C53—H53	119.00
C3—C2—H2A	109.00	C54—C55—H55	119.00
C3—C2—H2B	109.00	C56—C55—H55	119.00
H2A—C2—H2B	108.00	C51—C56—H56	120.00
C3—C4—H4A	109.00	C55—C56—H56	120.00

C6—C1—C2—C3	52.74 (16)	C4—C5—C51—C52	−88.85 (14)
C11—C1—C2—C3	175.47 (14)	C4—C5—C51—C56	89.28 (15)
C12—C1—C2—C3	−65.40 (19)	C6—C5—C51—C52	147.10 (12)
C2—C1—C6—C5	−58.85 (15)	C6—C5—C51—C56	−34.77 (17)
C11—C1—C6—C5	178.91 (12)	C5—C51—C52—C53	178.29 (12)
C12—C1—C6—C5	59.39 (14)	C56—C51—C52—C53	0.1 (2)
C1—C2—C3—O3	130.73 (15)	C5—C51—C56—C55	−179.06 (13)
C1—C2—C3—C4	−49.13 (17)	C52—C51—C56—C55	−0.9 (2)
O3—C3—C4—C5	−131.91 (13)	C51—C52—C53—C54	1.5 (2)
C2—C3—C4—C5	47.96 (15)	C52—C53—C54—C15	176.87 (13)
C3—C4—C5—C6	−51.08 (14)	C52—C53—C54—C55	−2.2 (2)
C3—C4—C5—C51	−177.30 (10)	C15—C54—C55—C56	−177.71 (14)
C4—C5—C6—C1	58.21 (15)	C53—C54—C55—C56	1.3 (2)
C51—C5—C6—C1	−177.70 (11)	C54—C55—C56—C51	0.2 (2)

Symmetry codes: (i) x, y−1, z; (ii) −x, y−1, −z+1/2; (iii) −x, −y+1, −z+1; (iv) −x, −y+2, −z+1; (v) x−1/2, y−1/2, z; (vi) x+1/2, y+1/2, z; (vii) −x, y, −z+1/2; (viii) −x+1/2, −y+3/2, −z+1; (ix) x, y+1, z; (x) −x, y+1, −z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C4—H4A···Cg^vii	0.99	2.61	3.5425 (15)	157

Symmetry code: (vii) −x, y, −z+1/2.

Experimental details

Crystal data
Chemical formula	C₁₅H₁₇NO
M_r	227.30
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	160
a, b, c (Å)	23.4475 (5), 6.0370 (1), 21.0740 (5)
β (°)	123.267 (1)
V (Å³)	2494.22 (9)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.25 × 0.20 × 0.10

Data collection
Diffractometer	Nonius KappaCCD area-detector diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	37687, 3640, 2682
R_int	0.054
(sin θ/λ)_max (Å⁻¹)	0.705

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.052, 0.170, 1.08
No. of reflections	3640
No. of parameters	154
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.42, −0.27

Computer programs: COLLECT (Nonius, 2000), DENZO-SMN (Otwinowski & Minor, 1997), DENZO-SMN and SCALEPACK (Otwinowski & Minor, 1997), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), PLATON (Spek, 2003).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C4—H4A···Cgⁱ	0.99	2.61	3.5425 (15)	157

Symmetry code: (i) −x, y, −z+1/2.

Acknowledgements

AT thanks the UGC, India, for the award of a Minor Research Project [File No. MRP-2355/06(UGC-SERO), Link No. 2355, 10/01/2007].

References

Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565. CrossRef IUCr Journals Google Scholar
Nonius (2000). COLLECT. Nonius BV, Delft, The Netherlands. Google Scholar
Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter & R. M. Sweet, pp. 307–326. London: Academic Press. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Spek, A. L. (2003). J. Appl. Cryst. 36, 7–13. Web of Science CrossRef CAS IUCr Journals Google Scholar
Subramanyam, M., Thiruvalluvar, A., Sabapathy Mohan, R. T. & Kamatchi, S. (2007). Acta Cryst. E63, o2715–o2716. Web of Science CSD CrossRef IUCr Journals Google Scholar