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ISSN: 2056-9890

r-2,c-6-Bis(4-fluoro­phen­yl)-t-3,t-5-di­methyl­piperidin-4-one

aCentre of Advanced Study in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai 600 025, India, bDepartment of Chemistry, Annamalai University, Annamalai Nagar 608 002, India, and cLaboratory of X-ray Crystallography, Indian Institute of Chemical Technology, Hyderabad 500 007, India
*Correspondence e-mail: d_velu@yahoo.com

(Received 11 December 2007; accepted 29 December 2007; online 11 January 2008)

In the title compound, C19H19F2NO, the piperidinone ring adopts a chair conformation. The crystal packing is stabilized by C—H⋯O and C—H⋯F inter­molecular inter­actions, generating centrosymmetric dimers of R22(14) and R22(24) rings.

Related literature

For related literature, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]); Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]); Ganellin & Spickett (1965[Ganellin, C. R. & Spickett, R. G. W. (1965). J. Med. Chem. 8, 619-625.]); Nardelli (1983[Nardelli, M. (1983). Acta Cryst. C39, 1141-1142.]); Noller & Baliah (1948[Noller, C. R. & Baliah, V. (1948). J. Am. Chem. Soc. 70, 3853-3855.]).

[Scheme 1]

Experimental

Crystal data
  • C19H19F2NO

  • Mr = 315.35

  • Monoclinic, P 21 /n

  • a = 7.3830 (6) Å

  • b = 24.0102 (19) Å

  • c = 9.4278 (7) Å

  • β = 101.727 (1)°

  • V = 1636.4 (2) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 293 (2) K

  • 0.27 × 0.24 × 0.22 mm

Data collection
  • Bruker SMART APEX CCD area-detector diffractometer

  • Absorption correction: none

  • 18490 measured reflections

  • 3851 independent reflections

  • 2773 reflections with I > 2σ(I)

  • Rint = 0.020

Refinement
  • R[F2 > 2σ(F2)] = 0.061

  • wR(F2) = 0.212

  • S = 1.04

  • 3851 reflections

  • 210 parameters

  • H-atom parameters constrained

  • Δρmax = 0.52 e Å−3

  • Δρmin = −0.43 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C11—H11⋯O1i 0.93 2.49 3.400 (3) 165
C18—H18⋯F1ii 0.93 2.54 3.197 (3) 128
Symmetry codes: (i) -x+1, -y, -z+2; (ii) -x+2, -y, -z+1.

Data collection: SMART (Bruker, 2001[Bruker (2001). SMART (Version. 5.625/NT/2000) and SAINT (Version 6.28a). Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2001[Bruker (2001). SMART (Version. 5.625/NT/2000) and SAINT (Version 6.28a). Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]); software used to prepare material for publication: SHELXL97 and PARST (Nardelli, 1995[Nardelli, M. (1995). J. Appl. Cryst. 28, 659.]).

Supporting information


Comment top

Substituted piperidin-4-ones are important synthetic intermediates for the preparation of various alkaloids and pharmaceuticals (Ganellin and Spickett, 1965). Several substituted piperidin-4-ones and their derivatives are easily synthesized by Noller and Baliah (1948). Piperidine and their derivatives have different conformation depending on the level of substitution of heterocyclic ring. The present investigation was undertaken to establish the structure, conformation and the possible biological functions. As the substituted piperidin-4-one compounds are of great pharmaceutical importance, we have undertaken the three dimensional crystal structure determination of the title compound, by X-ray diffraction (Fig.1).

The bond lengths and bond angles are comparable with the literature values (Allen et al., 1987). The flourine atoms F1 and F2 lie 0.019 (2)Å and -0.003 (2) Å, respectively, from the plane of the phenyl rings to which they are attached. The dihedral angle between the two phenyl rings is 50.4 (1)°.

The piperidinone ring adopts chair conformation with the puckering parameters (Cremer & Pople, 1975) and the smallest displacement asymmetry parameters (Nardelli, 1983) being q2 = 0.089 (2) Å, q3 = -0.573 (2) Å; QT = 0.580 (2)Å and θ = 171.2 (2)°.

The crystal packing is stabilized by C—H···O and C—H···F intermolecular interactions generating centrosymmetric dimers of R22(14) and R22(24) rings, respectively.

Related literature top

For related literature, see: Allen et al. (1987); Cremer & Pople (1975); Ganellin & Spickett (1965); Nardelli (1983); Noller & Baliah (1948).

Experimental top

The title compound was prepared by the condensation of pentane-3-one, 4-flurobenzaldehyde and ammonium acetate in 1: 2: 1 molar ratio in ethanol as reported by Noller and Baliah (1948) Diffraction quality crystal was obtained by recrystalization of the crude sample from ethanol. 1H NMR (CDCl3, p.p.m): δ 0.82 (d, 6H, J=6.54 Hz), 2.73 (m, 2H), 3.59 (t, 2H, J=10.27 Hz), 2.02 (s, 1H), 7.37 and 7.03 (d, 8H).

Refinement top

All H-atoms were refined using a riding model with d(C—H) = 0.93 Å, Uiso=1.2Ueq (C) for aromatic, 0.98 Å, Uiso = 1.2Ueq (C) for CH, 0.96 Å, Uiso = 1.5U eq (C) for CH3 atoms, and with d(N—H) = 0.86 Å, Uiso = 1.2Ueq (N) for the NH group.

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PARST (Nardelli, 1995).

Figures top
[Figure 1] Fig. 1. The molecular structure of title compound, showing 30% probability displacement ellipsoids.
[Figure 2] Fig. 2. The molecular packing of (I), viewed down the a axis. For clarity, hydrogen atoms which are not involved in hydrogen bonding were omitted.
r-2,c-6-Bis(4-fluorophenyl)-t-3,t-5-dimethylpiperidin-4-one top
Crystal data top
C19H19F2NOF(000) = 664
Mr = 315.35Dx = 1.280 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 2923 reflections
a = 7.3830 (6) Åθ = 2.4–28.1°
b = 24.0102 (19) ŵ = 0.09 mm1
c = 9.4278 (7) ÅT = 293 K
β = 101.727 (1)°Block, colourless
V = 1636.4 (2) Å30.27 × 0.24 × 0.22 mm
Z = 4
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer
2773 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.020
Graphite monochromatorθmax = 28.1°, θmin = 2.4°
ω scansh = 99
18490 measured reflectionsk = 3131
3851 independent reflectionsl = 1212
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)] = 0.061Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.212H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.1249P)2 + 0.205P]
where P = (Fo2 + 2Fc2)/3
3851 reflections(Δ/σ)max < 0.001
210 parametersΔρmax = 0.52 e Å3
0 restraintsΔρmin = 0.43 e Å3
Crystal data top
C19H19F2NOV = 1636.4 (2) Å3
Mr = 315.35Z = 4
Monoclinic, P21/nMo Kα radiation
a = 7.3830 (6) ŵ = 0.09 mm1
b = 24.0102 (19) ÅT = 293 K
c = 9.4278 (7) Å0.27 × 0.24 × 0.22 mm
β = 101.727 (1)°
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer
2773 reflections with I > 2σ(I)
18490 measured reflectionsRint = 0.020
3851 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0610 restraints
wR(F2) = 0.212H-atom parameters constrained
S = 1.04Δρmax = 0.52 e Å3
3851 reflectionsΔρmin = 0.43 e Å3
210 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
xyzUiso*/Ueq
C10.6972 (2)0.02549 (6)0.79954 (16)0.0546 (4)
H10.70190.02850.90390.066*
C20.4928 (2)0.01783 (7)0.72123 (19)0.0624 (4)
H20.49180.01470.61740.075*
C30.3828 (2)0.06935 (7)0.74162 (19)0.0637 (4)
C40.4655 (2)0.12406 (7)0.7076 (2)0.0637 (4)
H40.46540.12440.60360.076*
C50.6706 (2)0.12620 (6)0.78990 (18)0.0585 (4)
H50.67360.12470.89420.070*
C60.8102 (2)0.02404 (6)0.77288 (17)0.0558 (4)
C70.8517 (2)0.03400 (7)0.63869 (18)0.0617 (4)
H70.82030.00750.56580.074*
C80.9388 (3)0.08247 (8)0.6106 (2)0.0734 (5)
H80.96530.08910.51970.088*
C90.9851 (3)0.12059 (8)0.7203 (3)0.0784 (6)
C100.9494 (3)0.11202 (8)0.8545 (3)0.0834 (6)
H100.98290.13850.92700.100*
C110.8626 (3)0.06341 (8)0.8813 (2)0.0701 (5)
H110.83890.05690.97310.084*
C120.4069 (3)0.03515 (10)0.7657 (3)0.0970 (7)
H12A0.42170.03610.86920.145*
H12B0.46710.06690.73390.145*
H12C0.27760.03600.72200.145*
C130.3516 (3)0.17334 (10)0.7391 (3)0.1006 (8)
H13A0.22740.16980.68430.151*
H13B0.40540.20720.71240.151*
H13C0.34980.17420.84060.151*
C140.7637 (2)0.17899 (7)0.75681 (19)0.0638 (4)
C150.8070 (3)0.22048 (8)0.8600 (3)0.0826 (6)
H150.78170.21560.95190.099*
C160.8895 (4)0.27015 (9)0.8253 (4)0.1013 (8)
H160.91910.29840.89360.122*
C170.9248 (3)0.27607 (8)0.6917 (4)0.0966 (8)
C180.8849 (3)0.23645 (8)0.5878 (3)0.0898 (6)
H180.91130.24190.49650.108*
C190.8036 (3)0.18753 (7)0.6218 (2)0.0720 (5)
H190.77520.15980.55190.086*
N10.76605 (17)0.07730 (5)0.74933 (14)0.0547 (3)
H1A0.85320.07890.70120.066*
O10.23876 (19)0.06688 (7)0.78279 (19)0.0912 (5)
F11.0695 (2)0.16840 (5)0.6943 (2)0.1173 (5)
F21.0055 (3)0.32416 (6)0.6583 (3)0.1454 (7)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0543 (8)0.0562 (8)0.0523 (8)0.0027 (6)0.0080 (6)0.0002 (6)
C20.0525 (8)0.0638 (10)0.0695 (10)0.0072 (7)0.0093 (7)0.0038 (7)
C30.0502 (8)0.0763 (11)0.0633 (9)0.0018 (7)0.0084 (7)0.0059 (7)
C40.0509 (8)0.0639 (10)0.0743 (10)0.0065 (7)0.0079 (7)0.0064 (7)
C50.0544 (8)0.0582 (9)0.0605 (9)0.0025 (6)0.0060 (7)0.0076 (6)
C60.0510 (8)0.0525 (8)0.0605 (8)0.0040 (6)0.0032 (6)0.0024 (6)
C70.0579 (9)0.0612 (9)0.0634 (9)0.0009 (7)0.0062 (7)0.0013 (7)
C80.0653 (10)0.0724 (11)0.0813 (12)0.0021 (8)0.0118 (9)0.0131 (9)
C90.0643 (11)0.0548 (10)0.1119 (16)0.0029 (7)0.0080 (10)0.0088 (9)
C100.0781 (12)0.0635 (10)0.1024 (15)0.0059 (9)0.0038 (11)0.0227 (10)
C110.0735 (11)0.0676 (10)0.0659 (10)0.0017 (8)0.0068 (8)0.0106 (8)
C120.0677 (12)0.0771 (13)0.146 (2)0.0166 (10)0.0219 (13)0.0080 (13)
C130.0664 (12)0.0806 (14)0.152 (2)0.0176 (10)0.0151 (12)0.0246 (14)
C140.0507 (8)0.0528 (9)0.0826 (11)0.0072 (6)0.0011 (7)0.0059 (7)
C150.0809 (13)0.0637 (11)0.0947 (13)0.0047 (9)0.0027 (10)0.0171 (9)
C160.0944 (16)0.0576 (11)0.137 (2)0.0005 (10)0.0127 (15)0.0248 (13)
C170.0759 (13)0.0525 (11)0.155 (2)0.0002 (9)0.0075 (14)0.0060 (12)
C180.0858 (14)0.0607 (11)0.1247 (18)0.0027 (9)0.0259 (13)0.0133 (11)
C190.0701 (10)0.0563 (9)0.0901 (13)0.0003 (8)0.0172 (9)0.0003 (8)
N10.0475 (6)0.0518 (7)0.0642 (8)0.0015 (5)0.0101 (5)0.0008 (5)
O10.0608 (8)0.1076 (11)0.1127 (12)0.0004 (7)0.0352 (8)0.0006 (8)
F10.1099 (11)0.0692 (8)0.1703 (15)0.0267 (7)0.0223 (10)0.0127 (8)
F20.1327 (14)0.0643 (8)0.236 (2)0.0278 (8)0.0287 (13)0.0108 (10)
Geometric parameters (Å, º) top
C1—N11.4588 (19)C9—C101.359 (3)
C1—C61.503 (2)C10—C111.379 (3)
C1—C21.550 (2)C10—H100.9300
C1—H10.9800C11—H110.9300
C2—C31.513 (2)C12—H12A0.9600
C2—C121.518 (3)C12—H12B0.9600
C2—H20.9800C12—H12C0.9600
C3—O11.206 (2)C13—H13A0.9600
C3—C41.510 (2)C13—H13B0.9600
C4—C131.516 (2)C13—H13C0.9600
C4—C51.556 (2)C14—C191.379 (3)
C4—H40.9800C14—C151.384 (3)
C5—N11.4595 (19)C15—C161.408 (3)
C5—C141.504 (2)C15—H150.9300
C5—H50.9800C16—C171.345 (4)
C6—C71.382 (2)C16—H160.9300
C6—C111.388 (2)C17—C181.354 (4)
C7—C81.381 (2)C17—F21.365 (3)
C7—H70.9300C18—C191.386 (3)
C8—C91.371 (3)C18—H180.9300
C8—H80.9300C19—H190.9300
C9—F11.352 (2)N1—H1A0.8600
N1—C1—C6112.25 (12)C9—C10—C11118.93 (18)
N1—C1—C2108.44 (12)C9—C10—H10120.5
C6—C1—C2110.25 (12)C11—C10—H10120.5
N1—C1—H1108.6C10—C11—C6120.77 (18)
C6—C1—H1108.6C10—C11—H11119.6
C2—C1—H1108.6C6—C11—H11119.6
C3—C2—C12112.65 (15)C2—C12—H12A109.5
C3—C2—C1109.75 (13)C2—C12—H12B109.5
C12—C2—C1112.88 (15)H12A—C12—H12B109.5
C3—C2—H2107.1C2—C12—H12C109.5
C12—C2—H2107.1H12A—C12—H12C109.5
C1—C2—H2107.1H12B—C12—H12C109.5
O1—C3—C4122.16 (16)C4—C13—H13A109.5
O1—C3—C2122.14 (16)C4—C13—H13B109.5
C4—C3—C2115.70 (13)H13A—C13—H13B109.5
C3—C4—C13111.89 (16)C4—C13—H13C109.5
C3—C4—C5108.50 (13)H13A—C13—H13C109.5
C13—C4—C5113.54 (15)H13B—C13—H13C109.5
C3—C4—H4107.6C19—C14—C15118.66 (18)
C13—C4—H4107.6C19—C14—C5120.60 (15)
C5—C4—H4107.6C15—C14—C5120.73 (18)
N1—C5—C14111.00 (13)C14—C15—C16119.7 (2)
N1—C5—C4108.39 (12)C14—C15—H15120.1
C14—C5—C4111.32 (13)C16—C15—H15120.1
N1—C5—H5108.7C17—C16—C15118.8 (2)
C14—C5—H5108.7C17—C16—H16120.6
C4—C5—H5108.7C15—C16—H16120.6
C7—C6—C11118.41 (16)C16—C17—C18123.2 (2)
C7—C6—C1121.60 (14)C16—C17—F2118.8 (2)
C11—C6—C1119.79 (15)C18—C17—F2118.0 (3)
C8—C7—C6121.34 (16)C17—C18—C19118.0 (2)
C8—C7—H7119.3C17—C18—H18121.0
C6—C7—H7119.3C19—C18—H18121.0
C9—C8—C7118.15 (19)C14—C19—C18121.55 (19)
C9—C8—H8120.9C14—C19—H19119.2
C7—C8—H8120.9C18—C19—H19119.2
F1—C9—C10118.7 (2)C5—N1—C1112.48 (13)
F1—C9—C8118.9 (2)C5—N1—H1A123.8
C10—C9—C8122.38 (18)C1—N1—H1A123.8
N1—C1—C2—C353.46 (17)C7—C8—C9—C100.5 (3)
C6—C1—C2—C3176.73 (13)F1—C9—C10—C11179.75 (17)
N1—C1—C2—C12179.98 (15)C8—C9—C10—C110.4 (3)
C6—C1—C2—C1256.71 (19)C9—C10—C11—C60.8 (3)
C12—C2—C3—O13.1 (3)C7—C6—C11—C101.8 (3)
C1—C2—C3—O1129.78 (18)C1—C6—C11—C10173.17 (16)
C12—C2—C3—C4176.70 (16)N1—C5—C14—C1950.64 (19)
C1—C2—C3—C450.01 (19)C4—C5—C14—C1970.19 (19)
O1—C3—C4—C133.0 (3)N1—C5—C14—C15130.90 (16)
C2—C3—C4—C13176.83 (16)C4—C5—C14—C15108.27 (18)
O1—C3—C4—C5129.00 (18)C19—C14—C15—C160.2 (3)
C2—C3—C4—C550.79 (19)C5—C14—C15—C16178.30 (17)
C3—C4—C5—N155.74 (18)C14—C15—C16—C170.1 (3)
C13—C4—C5—N1179.19 (16)C15—C16—C17—C180.0 (4)
C3—C4—C5—C14178.09 (13)C15—C16—C17—F2179.76 (19)
C13—C4—C5—C1456.8 (2)C16—C17—C18—C190.0 (4)
N1—C1—C6—C750.19 (19)F2—C17—C18—C19179.78 (18)
C2—C1—C6—C770.83 (18)C15—C14—C19—C180.2 (3)
N1—C1—C6—C11135.01 (16)C5—C14—C19—C18178.32 (16)
C2—C1—C6—C11103.97 (17)C17—C18—C19—C140.1 (3)
C11—C6—C7—C81.7 (2)C14—C5—N1—C1171.33 (12)
C1—C6—C7—C8173.18 (15)C4—C5—N1—C166.12 (17)
C6—C7—C8—C90.6 (3)C6—C1—N1—C5173.32 (12)
C7—C8—C9—F1179.65 (16)C2—C1—N1—C564.62 (16)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C11—H11···O1i0.932.493.400 (3)165
C18—H18···F1ii0.932.543.197 (3)128
Symmetry codes: (i) x+1, y, z+2; (ii) x+2, y, z+1.

Experimental details

Crystal data
Chemical formulaC19H19F2NO
Mr315.35
Crystal system, space groupMonoclinic, P21/n
Temperature (K)293
a, b, c (Å)7.3830 (6), 24.0102 (19), 9.4278 (7)
β (°) 101.727 (1)
V3)1636.4 (2)
Z4
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.27 × 0.24 × 0.22
Data collection
DiffractometerBruker SMART APEX CCD area-detector
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
18490, 3851, 2773
Rint0.020
(sin θ/λ)max1)0.662
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.061, 0.212, 1.04
No. of reflections3851
No. of parameters210
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.52, 0.43

Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SHELXS97 (Sheldrick, 2008), PLATON (Spek, 2003), SHELXL97 (Sheldrick, 2008) and PARST (Nardelli, 1995).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C11—H11···O1i0.932.493.400 (3)164.6
C18—H18···F1ii0.932.543.197 (3)127.54
Symmetry codes: (i) x+1, y, z+2; (ii) x+2, y, z+1.
 

Acknowledgements

DG thanks the CSIR, India, for the award of a Senior Research Fellowship. DV thanks the DST, India, for a major research project. The Department of Science and Technology (DST–FIST) and the University Grants Commission (UGC), Government of India, are acknowledged by DV for providing facilities to the department.

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