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ISSN: 2056-9890

9-(2-Chloro­benzyl­­idene)anthracen-10(9H)-one

aDepartment of Chemistry, College of Sciences, King Saud University, PO Box 2455, Riyadh 11451, Saudi Arabia, and bDepartment of Physics, The Madura College, Madurai 625 011, India
*Correspondence e-mail: ambujasureshj@yahoo.com

(Received 30 December 2012; accepted 24 March 2013; online 5 April 2013)

In the title compound, C21H13ClO, the central anthracene system is distorted towards a boat conformation and the outer rings are not coplanar with the central ring [dihedral angles = 7.79 (1) and 11.90 (1)°]. The crystal structure features inversion dimers with graph-set motif R22(18) formed by C—H⋯O inter­actions.

Related literature

For ring conformations, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]). For anthracene derivatives see: Alston et al. (1979[Alston, P. V., Ottenbrite, R. M. & Newby, J. (1979). J. Org. Chem. 44, 4939-4943.]); Kaplan & Conroy (1963[Kaplan, F. & Conroy, H. (1963). J. Org. Chem. 28, 1593-1596.]); Meek et al. (1960[Meek, J. S., Wilgus, D. R. & Dann, J. R. (1960). J. Am. Chem. Soc. 82, 2566-2569.]); Singh & Ningombom (2010[Singh, M. D. & Ningombom, A. (2010). Indian J. Chem. Sect. B, 49, 789-794.]); Verma & Singh (1977[Verma, S. M. & Singh, M. D. (1977). J. Org. Chem. 42, 3736-3740.]). For hydrogen bonding, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data
  • C21H13ClO

  • Mr = 316.76

  • Triclinic, [P \overline 1]

  • a = 7.9106 (10) Å

  • b = 8.3598 (10) Å

  • c = 12.6906 (15) Å

  • α = 82.813 (7)°

  • β = 83.979 (7)°

  • γ = 67.741 (6)°

  • V = 769.09 (16) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.25 mm−1

  • T = 293 K

  • 0.21 × 0.19 × 0.17 mm

Data collection
  • Bruker Kappa APEXII diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS, University of Göttingen, Germany.]) Tmin = 0.967, Tmax = 0.974

  • 11698 measured reflections

  • 3182 independent reflections

  • 2715 reflections with I > 2σ(I)

  • Rint = 0.034

Refinement
  • R[F2 > 2σ(F2)] = 0.045

  • wR(F2) = 0.130

  • S = 1.06

  • 3182 reflections

  • 208 parameters

  • H-atom parameters constrained

  • Δρmax = 0.34 e Å−3

  • Δρmin = −0.50 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C17—H17⋯O1i 0.93 2.60 3.482 (2) 159
Symmetry code: (i) -x+1, -y, -z+1.

Data collection: APEX2 (Bruker, 2004[Bruker (2004). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2004[Bruker (2004). APEX2 and SAINT. 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, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

The compound anthracene has been known for a long time and its properties have been extensively studied. The regio and sterio-selectivity of substituted anthracenes in Diels-Alder reactions have been investigated and reported (Alston et al., (1979); Meek et al., (1960); Kaplan & Conroy, 1963; Verma & Singh, 1977; Singh & Ningombom, 2010). In view of this we have synthesized the title compound to study its crystal structure.

In the title compound (Fig 1),C21H13ClO, the benzene rings A and C in the anthracene moiety are almost individually planar with r.m.s deviation of 0.0071, and 0.0107 Å, respectively.The central anthracene ring B is distorted towards a boat conformation as evidenced by the puckering parameters q2 = 0.2074 (17) Å, θ = 76.8 (5)°, ϕ =5.9 (5)°(Cremer & Pople, 1975). The aromatic ring B is not coplanar with the aromatic rings A and C, as evidenced by the dihedral angles of 7.79 (1)° (A/B) and 11.90 (1)° (C/B) between them. The dihedral angle between the chlorophenyl ring and anthracene group is 55.69 (1)°. The carbonyl bond length C4=O1 [1.224 (2) Å] is somewhat longer than normal values due to involvement in a C—H···O contact. The twist of the chlorobenzene ring is indicated by the torsion angle C1—C15—C16—C17 is 60.72 (1)°. The range of C—C distances [1.365 (14)–1.484 (13) Å] and internal angles [117.00 (8)–121.55 (9)°] in the anthracene fragment are as expected for this type of molecule. In the crystal structure the C17—H17···O1 hydrogen bond connects two centrosymmetrically related molecules into dimers (Fig. 2) and generates a graph set motif of R22(18) (Bernstein et al., 1995). These centrosymmetric dimers are packed by weak Van der Waals interactions.

Related literature top

For ring conformations, see: Cremer & Pople (1975). For anthracene derivatives see: Alston et al. (1979); Kaplan & Conroy (1963); Meek et al. (1960); Singh & Ningombom (2010); Verma & Singh (1977). For hydrogen bonding, see: Bernstein et al. (1995).

Experimental top

A mixture of anthrone (500 mg, 2.57) and 2-chlorobenzaldehyde (362 mg, 2.57 mmol) were dissolved in ethanol (10 ml) at room temperature. Then, the reaction mixture was saturated with gaseous hydrogen chloride for 1 h. The reaction mixture became dark and was thereafter heated to reflux for 1 h. After completion of the reaction as evidenced by TLC, the reaction mixture was cooled to room temperature. The solid product was filtered and dried at room temperature and recrystallized through ethyl acetate by slow evaporation technique. Melting point: 125°C,Yield: 85%

Refinement top

H atoms were placed at calculated positions and allowed to ride on their carrier atoms with C—H = 0.93 Å. Uiso = 1.2Ueq(C) for CH2 and CH groups and Uiso = 1.5Ueq(C) for CH3 group.

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: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing 40% probability displacement ellipsoids and the atom-numbering scheme.
[Figure 2] Fig. 2. The partial packing diagram showing C—H···.O hydrogen bonding generating graph set motif R22(18).
9-(2-Chlorobenzylidene)anthracen-10(9H)-one top
Crystal data top
C21H13ClOZ = 2
Mr = 316.76F(000) = 328
Triclinic, P1Dx = 1.368 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.9106 (10) ÅCell parameters from 2000 reflections
b = 8.3598 (10) Åθ = 1.6–26.5°
c = 12.6906 (15) ŵ = 0.25 mm1
α = 82.813 (7)°T = 293 K
β = 83.979 (7)°Block, colourless
γ = 67.741 (6)°0.21 × 0.19 × 0.17 mm
V = 769.09 (16) Å3
Data collection top
Bruker Kappa APEXII
diffractometer
3182 independent reflections
Radiation source: fine-focus sealed tube2715 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.034
Detector resolution: 0 pixels mm-1θmax = 26.5°, θmin = 1.6°
ω and ϕ scansh = 99
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
k = 1010
Tmin = 0.967, Tmax = 0.974l = 1515
11698 measured reflections
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)] = 0.045Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.130H-atom parameters constrained
S = 1.06 w = 1/[σ2(Fo2) + (0.0637P)2 + 0.2067P]
where P = (Fo2 + 2Fc2)/3
3182 reflections(Δ/σ)max < 0.001
208 parametersΔρmax = 0.34 e Å3
0 restraintsΔρmin = 0.50 e Å3
Crystal data top
C21H13ClOγ = 67.741 (6)°
Mr = 316.76V = 769.09 (16) Å3
Triclinic, P1Z = 2
a = 7.9106 (10) ÅMo Kα radiation
b = 8.3598 (10) ŵ = 0.25 mm1
c = 12.6906 (15) ÅT = 293 K
α = 82.813 (7)°0.21 × 0.19 × 0.17 mm
β = 83.979 (7)°
Data collection top
Bruker Kappa APEXII
diffractometer
3182 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
2715 reflections with I > 2σ(I)
Tmin = 0.967, Tmax = 0.974Rint = 0.034
11698 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0450 restraints
wR(F2) = 0.130H-atom parameters constrained
S = 1.06Δρmax = 0.34 e Å3
3182 reflectionsΔρmin = 0.50 e Å3
208 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
C10.3985 (2)0.33688 (19)0.34305 (11)0.0387 (3)
C20.3506 (2)0.3882 (2)0.45334 (11)0.0399 (3)
C30.4487 (2)0.2788 (2)0.53727 (12)0.0442 (4)
C40.6127 (2)0.1233 (2)0.51677 (13)0.0477 (4)
C50.6848 (2)0.1024 (2)0.40495 (13)0.0442 (4)
C60.5841 (2)0.20832 (19)0.32087 (11)0.0400 (3)
C70.6699 (2)0.1932 (2)0.21833 (13)0.0489 (4)
H70.60750.26390.16120.059*
C80.8450 (3)0.0755 (3)0.20049 (16)0.0617 (5)
H80.89910.06760.13170.074*
C90.9414 (3)0.0313 (3)0.28405 (18)0.0678 (5)
H91.05910.11160.27150.081*
C100.8613 (3)0.0173 (2)0.38533 (16)0.0591 (5)
H100.92560.08850.44170.071*
C110.2045 (2)0.5395 (2)0.47810 (13)0.0486 (4)
H110.14060.61590.42330.058*
C120.1527 (3)0.5783 (3)0.58185 (14)0.0563 (4)
H120.05480.67970.59650.068*
C130.2466 (3)0.4659 (3)0.66409 (14)0.0624 (5)
H130.21000.49030.73430.075*
C140.3930 (3)0.3193 (3)0.64233 (13)0.0578 (5)
H140.45670.24520.69800.069*
C150.2700 (2)0.4023 (2)0.27142 (12)0.0440 (3)
H150.16560.49450.29170.053*
C160.2721 (2)0.3476 (2)0.16491 (11)0.0431 (3)
C170.2847 (3)0.1809 (2)0.15224 (15)0.0578 (4)
H170.29860.10020.21140.069*
C180.2771 (3)0.1331 (3)0.05306 (17)0.0674 (5)
H180.28670.02060.04590.081*
C190.2553 (3)0.2514 (3)0.03530 (15)0.0715 (6)
H190.24960.21900.10190.086*
C200.2419 (3)0.4165 (3)0.02466 (14)0.0701 (6)
H200.22750.49670.08410.084*
C210.2498 (2)0.4635 (2)0.07414 (13)0.0515 (4)
O10.6920 (2)0.02023 (19)0.58940 (10)0.0694 (4)
Cl10.23753 (11)0.67325 (7)0.08509 (4)0.0865 (2)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0462 (8)0.0407 (7)0.0310 (7)0.0192 (6)0.0033 (5)0.0010 (5)
C20.0480 (8)0.0445 (8)0.0323 (7)0.0236 (6)0.0025 (6)0.0012 (6)
C30.0555 (9)0.0536 (9)0.0324 (7)0.0306 (7)0.0065 (6)0.0004 (6)
C40.0573 (9)0.0510 (9)0.0410 (8)0.0276 (7)0.0145 (7)0.0071 (7)
C50.0498 (8)0.0412 (8)0.0442 (8)0.0190 (7)0.0101 (6)0.0006 (6)
C60.0455 (8)0.0407 (7)0.0373 (7)0.0194 (6)0.0062 (6)0.0023 (6)
C70.0496 (9)0.0557 (9)0.0398 (8)0.0176 (7)0.0030 (7)0.0050 (7)
C80.0530 (10)0.0730 (12)0.0532 (10)0.0154 (9)0.0034 (8)0.0159 (9)
C90.0526 (10)0.0647 (12)0.0711 (13)0.0014 (9)0.0041 (9)0.0170 (10)
C100.0585 (10)0.0490 (9)0.0618 (11)0.0077 (8)0.0181 (8)0.0030 (8)
C110.0580 (9)0.0502 (9)0.0390 (8)0.0215 (7)0.0008 (7)0.0058 (7)
C120.0675 (11)0.0596 (10)0.0480 (9)0.0302 (9)0.0096 (8)0.0173 (8)
C130.0845 (13)0.0812 (13)0.0338 (8)0.0438 (11)0.0054 (8)0.0156 (8)
C140.0752 (12)0.0744 (12)0.0324 (8)0.0379 (10)0.0078 (7)0.0007 (8)
C150.0452 (8)0.0489 (8)0.0331 (7)0.0127 (7)0.0021 (6)0.0018 (6)
C160.0406 (7)0.0534 (9)0.0336 (7)0.0155 (7)0.0049 (6)0.0015 (6)
C170.0709 (11)0.0588 (10)0.0472 (9)0.0288 (9)0.0075 (8)0.0008 (8)
C180.0833 (13)0.0667 (12)0.0627 (12)0.0366 (11)0.0037 (10)0.0165 (10)
C190.0924 (15)0.0898 (15)0.0429 (10)0.0415 (12)0.0053 (9)0.0186 (10)
C200.1010 (16)0.0799 (14)0.0327 (8)0.0377 (12)0.0100 (9)0.0008 (8)
C210.0621 (10)0.0547 (9)0.0353 (8)0.0193 (8)0.0060 (7)0.0008 (7)
O10.0783 (9)0.0725 (9)0.0492 (7)0.0220 (7)0.0208 (6)0.0190 (6)
Cl10.1501 (6)0.0594 (3)0.0527 (3)0.0429 (3)0.0109 (3)0.0024 (2)
Geometric parameters (Å, º) top
C1—C151.344 (2)C11—H110.9300
C1—C61.477 (2)C12—C131.383 (3)
C1—C21.484 (2)C12—H120.9300
C2—C111.396 (2)C13—C141.365 (3)
C2—C31.402 (2)C13—H130.9300
C3—C141.401 (2)C14—H140.9300
C3—C41.475 (2)C15—C161.477 (2)
C4—O11.2243 (19)C15—H150.9300
C4—C51.479 (2)C16—C171.387 (2)
C5—C101.394 (2)C16—C211.390 (2)
C5—C61.402 (2)C17—C181.381 (3)
C6—C71.400 (2)C17—H170.9300
C7—C81.377 (2)C18—C191.378 (3)
C7—H70.9300C18—H180.9300
C8—C91.386 (3)C19—C201.366 (3)
C8—H80.9300C19—H190.9300
C9—C101.370 (3)C20—C211.374 (2)
C9—H90.9300C20—H200.9300
C10—H100.9300C21—Cl11.7412 (19)
C11—C121.378 (2)
C15—C1—C6124.09 (13)C2—C11—H11119.2
C15—C1—C2118.82 (14)C11—C12—C13119.81 (17)
C6—C1—C2117.00 (12)C11—C12—H12120.1
C11—C2—C3117.96 (14)C13—C12—H12120.1
C11—C2—C1122.31 (13)C14—C13—C12120.02 (16)
C3—C2—C1119.67 (14)C14—C13—H13120.0
C14—C3—C2119.68 (16)C12—C13—H13120.0
C14—C3—C4119.23 (15)C13—C14—C3120.89 (16)
C2—C3—C4121.07 (14)C13—C14—H14119.6
O1—C4—C3121.67 (16)C3—C14—H14119.6
O1—C4—C5121.00 (16)C1—C15—C16128.78 (14)
C3—C4—C5117.22 (13)C1—C15—H15115.6
C10—C5—C6120.50 (16)C16—C15—H15115.6
C10—C5—C4118.28 (14)C17—C16—C21117.18 (15)
C6—C5—C4121.07 (14)C17—C16—C15121.17 (14)
C7—C6—C5117.52 (14)C21—C16—C15121.52 (15)
C7—C6—C1122.48 (13)C18—C17—C16120.94 (17)
C5—C6—C1119.91 (13)C18—C17—H17119.5
C8—C7—C6121.19 (16)C16—C17—H17119.5
C8—C7—H7119.4C19—C18—C17120.31 (19)
C6—C7—H7119.4C19—C18—H18119.8
C7—C8—C9120.66 (17)C17—C18—H18119.8
C7—C8—H8119.7C20—C19—C18119.76 (17)
C9—C8—H8119.7C20—C19—H19120.1
C10—C9—C8119.24 (17)C18—C19—H19120.1
C10—C9—H9120.4C19—C20—C21119.77 (18)
C8—C9—H9120.4C19—C20—H20120.1
C9—C10—C5120.85 (17)C21—C20—H20120.1
C9—C10—H10119.6C20—C21—C16122.03 (17)
C5—C10—H10119.6C20—C21—Cl1118.85 (14)
C12—C11—C2121.55 (16)C16—C21—Cl1119.10 (13)
C12—C11—H11119.2
C15—C1—C2—C1121.6 (2)C7—C8—C9—C100.8 (3)
C6—C1—C2—C11161.60 (14)C8—C9—C10—C50.1 (3)
C15—C1—C2—C3155.48 (15)C6—C5—C10—C91.4 (3)
C6—C1—C2—C321.3 (2)C4—C5—C10—C9174.18 (17)
C11—C2—C3—C143.0 (2)C3—C2—C11—C122.4 (2)
C1—C2—C3—C14174.19 (14)C1—C2—C11—C12174.72 (15)
C11—C2—C3—C4175.59 (14)C2—C11—C12—C130.1 (3)
C1—C2—C3—C47.2 (2)C11—C12—C13—C141.6 (3)
C14—C3—C4—O16.6 (2)C12—C13—C14—C31.0 (3)
C2—C3—C4—O1174.78 (15)C2—C3—C14—C131.4 (3)
C14—C3—C4—C5169.63 (14)C4—C3—C14—C13177.23 (16)
C2—C3—C4—C59.0 (2)C6—C1—C15—C169.2 (3)
O1—C4—C5—C1011.7 (2)C2—C1—C15—C16167.39 (15)
C3—C4—C5—C10164.58 (15)C1—C15—C16—C1760.7 (2)
O1—C4—C5—C6172.76 (15)C1—C15—C16—C21123.51 (19)
C3—C4—C5—C611.0 (2)C21—C16—C17—C180.6 (3)
C10—C5—C6—C72.2 (2)C15—C16—C17—C18176.60 (17)
C4—C5—C6—C7173.23 (14)C16—C17—C18—C190.5 (3)
C10—C5—C6—C1178.83 (15)C17—C18—C19—C200.3 (3)
C4—C5—C6—C13.4 (2)C18—C19—C20—C210.2 (3)
C15—C1—C6—C726.3 (2)C19—C20—C21—C160.3 (3)
C2—C1—C6—C7157.05 (14)C19—C20—C21—Cl1178.61 (17)
C15—C1—C6—C5157.24 (15)C17—C16—C21—C200.5 (3)
C2—C1—C6—C519.4 (2)C15—C16—C21—C20176.50 (17)
C5—C6—C7—C81.6 (2)C17—C16—C21—Cl1178.81 (13)
C1—C6—C7—C8178.12 (16)C15—C16—C21—Cl15.2 (2)
C6—C7—C8—C90.1 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C17—H17···O1i0.932.603.482 (2)159
Symmetry code: (i) x+1, y, z+1.

Experimental details

Crystal data
Chemical formulaC21H13ClO
Mr316.76
Crystal system, space groupTriclinic, P1
Temperature (K)293
a, b, c (Å)7.9106 (10), 8.3598 (10), 12.6906 (15)
α, β, γ (°)82.813 (7), 83.979 (7), 67.741 (6)
V3)769.09 (16)
Z2
Radiation typeMo Kα
µ (mm1)0.25
Crystal size (mm)0.21 × 0.19 × 0.17
Data collection
DiffractometerBruker Kappa APEXII
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.967, 0.974
No. of measured, independent and
observed [I > 2σ(I)] reflections
11698, 3182, 2715
Rint0.034
(sin θ/λ)max1)0.628
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.045, 0.130, 1.06
No. of reflections3182
No. of parameters208
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.34, 0.50

Computer programs: APEX2 (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C17—H17···O1i0.932.603.482 (2)159
Symmetry code: (i) x+1, y, z+1.
 

Acknowledgements

This project was supported by Research Center, Deanship of Scientific Research, College of Science, King Saud University.

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