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ISSN: 2056-9890

6-Methyl-2,4-di­phenyl­quinoline

aDepartment of Chemistry, State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, People's Republic of China
*Correspondence e-mail: huox03@lzu.cn

(Received 9 April 2008; accepted 24 May 2008; online 7 June 2008)

The mol­ecules of the title compound, C22H17N, are linked by weak inter­actions, among which the most prominent are C—H⋯π inter­actions. The dihedral angles between the phenyl rings and the quinoline ring system are 43.3 (3) and 21.4 (3)°. The title product resulted from a three-component reaction of benzaldehyde, 1-ethynylbenzene and p-toluidine via C—H activation of 1-ethynylbenzene catalyzed by CuI in the ionic liquid 1-butyl-3-methyl­imidazolium hexa­fluoro­phosphate.

Related literature

For related literature, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]); Park & Alper (2005[Park, S. B. & Alper, H. (2005). Chem. Commun. pp. 1315-1317.]); Shi et al. (2004[Shi, L., Tu, Y.-Q., Wang, M., Zhang, F.-M. & Fan, C.-A. (2004). Org. Lett. 6, 1001-1003.]); Skraup (1880[Skraup, H. (1880). Chem. Ber. 13, 2086-2087.]).

[Scheme 1]

Experimental

Crystal data
  • C22H17N

  • Mr = 295.37

  • Orthorhombic, P 21 21 21

  • a = 7.766 (1) Å

  • b = 9.851 (1) Å

  • c = 20.756 (2) Å

  • V = 1588.0 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.07 mm−1

  • T = 294 (2) K

  • 0.41 × 0.35 × 0.30 mm

Data collection
  • Bruker SMART CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.971, Tmax = 0.979

  • 8562 measured reflections

  • 1720 independent reflections

  • 1302 reflections with I > 2σ(I)

  • Rint = 0.051

Refinement
  • R[F2 > 2σ(F2)] = 0.043

  • wR(F2) = 0.120

  • S = 1.04

  • 1720 reflections

  • 210 parameters

  • H-atom parameters constrained

  • Δρmax = 0.17 e Å−3

  • Δρmin = −0.14 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg2 and Cg3 are the centroids of the C1–C6 and C14–C19 rings, respectively .

D—H⋯A D—H H⋯A DA D—H⋯A
C6—H6⋯Cg3i 0.93 2.75 3.551 (3) 145
C11—H11⋯Cg2i 0.93 2.92 3.726 (3) 146
Symmetry code: (i) [x+{\script{3\over 2}}, -y+{\script{1\over 2}}, -z].

Data collection: SMART (Bruker, 1998[Bruker (1998). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SMART; data reduction: SAINT (Bruker, 1998[Bruker (1998). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Quinolines and their derivatives are very important in medical chemistry because of their extensive occurrence in natural products. Also, quinolines possess a wide spectrum of biological activities. The classic method of quinoline synthesis is Skraup's procedure (Skraup, 1880). The synthesis of the title compound follows a study of transition-metal catalyzed multi-component reactions which is a powerful synthetic tool to access complex structures from simple precursors by a one-pot procedure (Shi et al., 2004; Park & Alper, 2005).

In the title compound, all the bond lengths are normal (Allen et al., 1987). The angle between both phenyl rings in the structure is 34.6 (3) °. The dihedral angle between the phenyl ring C1—C6 and the ring C14—C21/N1 is 43.3 (3) °. The dihedral angle between the C7—C12 phenyl ring and the C14—C21/N1 ring is 21.4 (3) °.

Related literature top

For related literature, see: Allen et al. (1987); Park & Alper (2005); Shi et al. (2004); Skraup (1880). Definition of the centroids: Cg3: C14–C19 Cg2: C1–C6.

Experimental top

The p-toluidine (1.5 mmol) and benzaldehyde(1.5 mmol) were taken along with a catalytic quantity of CuI (0.45 mmol) in ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate (5 ml) (Scheme 2). The resulting mixture was stirred at 298 K for 15 minutes. At this stage 1-ethynylbenzene (1 mmol) was quickly poured into the reaction mixture and the temperature was raised to 404 K, kept at this temperature for 6 hours, then cooled to room temperature. The product was extracted from the reaction mixture by addition of diethyl ether. (It was possible to recover ionic liquid layer and to use it again without any pretreatment.) The combined organic layer was concentrated and the desired product was isolated by silica gel column chromatography(petrol/EtOAc, 20:1). Colourless sheet crystals were recrystallized from the deuterated chloroform CDCl3 by evaporation in the course of several days. Their average size was 2.5-3 mm.

Refinement top

Though all the H atoms could be located in the difference electron-density maps, they were placed into the idealized positions and constrained to ride on their parent atoms. The constrained distances: C—H = 0.93 or 0.96 Å for the aryl or the methyl hydrogens, respectively. The hydrogens' isotropic displacement parameters : Uiso(H) = 1.2Ueq(C) or 1.5Ueq(C) for aryl or methyl hydrogens, respectively. In the absence of significant anomalous scattering effects 1413 Friedel pairs have been merged.

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SMART (Bruker, 1998); data reduction: SAINT (Bruker, 1998); 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: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure with the atom-numbering scheme. The displacement ellipsoids are drawn at the 30% probability level.
[Figure 2] Fig. 2. The formation of the title compound.
6-Methyl-2,4-diphenylquinoline top
Crystal data top
C22H17NF(000) = 624
Mr = 295.37Dx = 1.235 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P2ac2abCell parameters from 803 reflections
a = 7.766 (1) Åθ = 2.3–24.5°
b = 9.851 (1) ŵ = 0.07 mm1
c = 20.756 (2) ÅT = 294 K
V = 1588.0 (3) Å3Block, colourless
Z = 40.41 × 0.35 × 0.30 mm
Data collection top
Bruker SMART CCD area-detector
diffractometer
1720 independent reflections
Radiation source: fine-focus sealed tube1302 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.052
ω scansθmax = 25.5°, θmin = 2.0°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 89
Tmin = 0.971, Tmax = 0.979k = 1111
8562 measured reflectionsl = 2522
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.043H-atom parameters constrained
wR(F2) = 0.120 w = 1/[σ2(Fo2) + (0.0684P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.04(Δ/σ)max < 0.001
1720 reflectionsΔρmax = 0.17 e Å3
210 parametersΔρmin = 0.14 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008)
67 constraintsExtinction coefficient: 0.009 (2)
Primary atom site location: structure-invariant direct methods
Crystal data top
C22H17NV = 1588.0 (3) Å3
Mr = 295.37Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 7.766 (1) ŵ = 0.07 mm1
b = 9.851 (1) ÅT = 294 K
c = 20.756 (2) Å0.41 × 0.35 × 0.30 mm
Data collection top
Bruker SMART CCD area-detector
diffractometer
1720 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
1302 reflections with I > 2σ(I)
Tmin = 0.971, Tmax = 0.979Rint = 0.052
8562 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0430 restraints
wR(F2) = 0.120H-atom parameters constrained
S = 1.04Δρmax = 0.17 e Å3
1720 reflectionsΔρmin = 0.14 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
N10.8369 (3)0.4866 (3)0.14992 (11)0.0493 (6)
C10.6966 (4)0.5970 (3)0.34443 (12)0.0453 (7)
C20.7800 (4)0.5422 (3)0.39763 (13)0.0538 (8)
H20.86050.47330.39200.065*
C30.7440 (5)0.5893 (4)0.45891 (14)0.0640 (9)
H30.79970.55130.49420.077*
C40.6258 (5)0.6926 (4)0.46804 (14)0.0678 (10)
H40.60160.72380.50930.081*
C50.5439 (5)0.7489 (3)0.41549 (13)0.0621 (9)
H50.46490.81880.42140.074*
C60.5788 (4)0.7021 (3)0.35440 (13)0.0493 (7)
H60.52320.74090.31930.059*
C70.8147 (4)0.7190 (3)0.11564 (12)0.0448 (7)
C80.9118 (4)0.6959 (3)0.06060 (13)0.0562 (8)
H80.97180.61470.05620.067*
C90.9206 (5)0.7918 (3)0.01228 (14)0.0647 (9)
H90.98700.77500.02420.078*
C100.8318 (5)0.9124 (3)0.01757 (15)0.0638 (9)
H100.83750.97670.01520.077*
C110.7347 (4)0.9371 (3)0.07175 (14)0.0592 (9)
H110.67451.01820.07580.071*
C120.7268 (4)0.8410 (3)0.12009 (13)0.0524 (8)
H120.66080.85860.15650.063*
C130.7370 (3)0.5530 (3)0.27752 (13)0.0434 (7)
C140.7596 (3)0.4139 (3)0.25973 (13)0.0448 (7)
C150.7277 (4)0.3018 (3)0.30025 (13)0.0492 (7)
H150.68550.31750.34150.059*
C160.7564 (4)0.1704 (3)0.28110 (15)0.0522 (8)
C170.8282 (4)0.1481 (3)0.22001 (14)0.0559 (8)
H170.85700.06020.20770.067*
C180.8566 (4)0.2523 (3)0.17834 (14)0.0545 (8)
H180.90140.23420.13770.065*
C190.8189 (4)0.3880 (3)0.19587 (13)0.0454 (7)
C200.8015 (4)0.6132 (3)0.16636 (13)0.0447 (7)
C210.7571 (4)0.6497 (3)0.23033 (12)0.0472 (7)
H210.74130.74070.24060.057*
C220.7120 (5)0.0522 (3)0.32401 (16)0.0677 (10)
H22A0.66440.08530.36370.102*
H22B0.81410.00070.33290.102*
H22C0.62910.00460.30280.102*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0537 (14)0.0477 (15)0.0465 (14)0.0033 (13)0.0026 (11)0.0044 (11)
C10.0542 (16)0.0405 (15)0.0412 (15)0.0047 (14)0.0011 (13)0.0024 (13)
C20.0665 (19)0.0507 (18)0.0444 (16)0.0062 (16)0.0071 (14)0.0017 (13)
C30.086 (2)0.062 (2)0.0436 (16)0.012 (2)0.0136 (16)0.0016 (16)
C40.094 (3)0.068 (2)0.0423 (17)0.014 (2)0.0028 (17)0.0100 (16)
C50.076 (2)0.0515 (19)0.0586 (18)0.0029 (18)0.0090 (17)0.0136 (17)
C60.0576 (17)0.0474 (17)0.0429 (15)0.0015 (16)0.0037 (13)0.0029 (14)
C70.0497 (16)0.0444 (17)0.0404 (14)0.0003 (14)0.0010 (13)0.0034 (13)
C80.0662 (19)0.0513 (19)0.0512 (17)0.0081 (17)0.0083 (15)0.0005 (15)
C90.084 (2)0.064 (2)0.0465 (17)0.002 (2)0.0151 (16)0.0002 (17)
C100.092 (2)0.052 (2)0.0480 (18)0.004 (2)0.0054 (18)0.0059 (16)
C110.075 (2)0.0471 (18)0.0557 (18)0.0086 (18)0.0039 (16)0.0001 (15)
C120.0601 (17)0.0519 (18)0.0451 (15)0.0038 (16)0.0013 (14)0.0036 (15)
C130.0448 (16)0.0426 (16)0.0428 (14)0.0009 (14)0.0007 (13)0.0007 (13)
C140.0447 (16)0.0441 (16)0.0455 (15)0.0025 (14)0.0010 (12)0.0017 (13)
C150.0521 (17)0.0498 (18)0.0458 (15)0.0017 (15)0.0033 (13)0.0019 (13)
C160.0533 (18)0.0454 (18)0.0579 (17)0.0014 (15)0.0086 (15)0.0009 (15)
C170.0617 (18)0.0445 (18)0.0616 (19)0.0077 (16)0.0076 (16)0.0066 (16)
C180.0588 (18)0.0524 (19)0.0522 (18)0.0091 (17)0.0026 (14)0.0061 (17)
C190.0471 (15)0.0438 (17)0.0453 (15)0.0023 (14)0.0005 (13)0.0021 (13)
C200.0452 (15)0.0453 (17)0.0437 (15)0.0013 (14)0.0009 (12)0.0006 (13)
C210.0549 (17)0.0417 (16)0.0451 (15)0.0032 (14)0.0004 (14)0.0040 (14)
C220.079 (2)0.0488 (19)0.076 (2)0.0005 (18)0.0066 (19)0.0077 (18)
Geometric parameters (Å, º) top
N1—C201.322 (4)C10—H100.9300
N1—C191.369 (3)C11—C121.381 (4)
C1—C21.390 (4)C11—H110.9300
C1—C61.396 (4)C12—H120.9300
C1—C131.489 (4)C13—C211.375 (4)
C2—C31.383 (4)C13—C141.430 (4)
C2—H20.9300C14—C151.410 (4)
C3—C41.384 (5)C14—C191.426 (3)
C3—H30.9300C15—C161.373 (4)
C4—C51.379 (4)C15—H150.9300
C4—H40.9300C16—C171.403 (4)
C5—C61.376 (3)C16—C221.506 (4)
C5—H50.9300C17—C181.361 (4)
C6—H60.9300C17—H170.9300
C7—C121.385 (4)C18—C191.416 (4)
C7—C81.388 (4)C18—H180.9300
C7—C201.485 (4)C20—C211.418 (4)
C8—C91.380 (4)C21—H210.9300
C8—H80.9300C22—H22A0.9600
C9—C101.378 (5)C22—H22B0.9600
C9—H90.9300C22—H22C0.9600
C10—C111.376 (4)
C20—N1—C19118.0 (2)C11—C12—H12119.2
C2—C1—C6118.4 (3)C7—C12—H12119.2
C2—C1—C13122.0 (3)C21—C13—C14117.8 (2)
C6—C1—C13119.5 (2)C21—C13—C1119.1 (3)
C3—C2—C1120.4 (3)C14—C13—C1123.1 (2)
C3—C2—H2119.8C15—C14—C19118.1 (3)
C1—C2—H2119.8C15—C14—C13125.1 (2)
C2—C3—C4120.5 (3)C19—C14—C13116.8 (3)
C2—C3—H3119.8C16—C15—C14122.5 (3)
C4—C3—H3119.8C16—C15—H15118.8
C5—C4—C3119.6 (3)C14—C15—H15118.8
C5—C4—H4120.2C15—C16—C17118.3 (3)
C3—C4—H4120.2C15—C16—C22121.4 (3)
C6—C5—C4120.2 (3)C17—C16—C22120.3 (3)
C6—C5—H5119.9C18—C17—C16121.4 (3)
C4—C5—H5119.9C18—C17—H17119.3
C5—C6—C1120.9 (3)C16—C17—H17119.3
C5—C6—H6119.5C17—C18—C19121.0 (3)
C1—C6—H6119.5C17—C18—H18119.5
C12—C7—C8117.7 (3)C19—C18—H18119.5
C12—C7—C20121.8 (2)N1—C19—C18118.0 (2)
C8—C7—C20120.4 (3)N1—C19—C14123.6 (3)
C9—C8—C7120.9 (3)C18—C19—C14118.3 (3)
C9—C8—H8119.6N1—C20—C21122.1 (3)
C7—C8—H8119.6N1—C20—C7117.7 (2)
C10—C9—C8120.5 (3)C21—C20—C7120.2 (3)
C10—C9—H9119.7C13—C21—C20121.3 (3)
C8—C9—H9119.7C13—C21—H21119.4
C11—C10—C9119.4 (3)C20—C21—H21119.4
C11—C10—H10120.3C16—C22—H22A109.5
C9—C10—H10120.3C16—C22—H22B109.5
C10—C11—C12119.8 (3)H22A—C22—H22B109.5
C10—C11—H11120.1C16—C22—H22C109.5
C12—C11—H11120.1H22A—C22—H22C109.5
C11—C12—C7121.6 (3)H22B—C22—H22C109.5
C6—C1—C2—C31.2 (4)C13—C14—C15—C16178.1 (3)
C13—C1—C2—C3177.5 (3)C14—C15—C16—C173.2 (4)
C1—C2—C3—C40.6 (5)C14—C15—C16—C22176.6 (3)
C2—C3—C4—C50.2 (5)C15—C16—C17—C185.1 (5)
C3—C4—C5—C60.4 (5)C22—C16—C17—C18174.6 (3)
C4—C5—C6—C10.2 (5)C16—C17—C18—C191.8 (5)
C2—C1—C6—C51.0 (4)C20—N1—C19—C18179.9 (3)
C13—C1—C6—C5177.3 (3)C20—N1—C19—C141.8 (4)
C12—C7—C8—C90.3 (4)C17—C18—C19—N1174.7 (3)
C20—C7—C8—C9178.0 (3)C17—C18—C19—C143.5 (5)
C7—C8—C9—C100.5 (5)C15—C14—C19—N1172.8 (3)
C8—C9—C10—C110.4 (5)C13—C14—C19—N17.1 (4)
C9—C10—C11—C120.1 (5)C15—C14—C19—C185.3 (4)
C10—C11—C12—C70.0 (5)C13—C14—C19—C18174.8 (3)
C8—C7—C12—C110.1 (4)C19—N1—C20—C214.1 (4)
C20—C7—C12—C11177.7 (3)C19—N1—C20—C7177.7 (2)
C2—C1—C13—C21135.1 (3)C12—C7—C20—N1157.1 (3)
C6—C1—C13—C2141.1 (4)C8—C7—C20—N120.5 (4)
C2—C1—C13—C1443.6 (4)C12—C7—C20—C2124.7 (4)
C6—C1—C13—C14140.2 (3)C8—C7—C20—C21157.8 (3)
C21—C13—C14—C15173.5 (3)C14—C13—C21—C201.0 (4)
C1—C13—C14—C157.8 (4)C1—C13—C21—C20177.8 (2)
C21—C13—C14—C196.3 (4)N1—C20—C21—C134.6 (4)
C1—C13—C14—C19172.4 (3)C7—C20—C21—C13177.2 (3)
C19—C14—C15—C162.0 (4)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6···Cg3i0.932.753.551 (3)145
C11—H11···Cg2i0.932.923.726 (3)146
Symmetry code: (i) x+3/2, y+1/2, z.

Experimental details

Crystal data
Chemical formulaC22H17N
Mr295.37
Crystal system, space groupOrthorhombic, P212121
Temperature (K)294
a, b, c (Å)7.766 (1), 9.851 (1), 20.756 (2)
V3)1588.0 (3)
Z4
Radiation typeMo Kα
µ (mm1)0.07
Crystal size (mm)0.41 × 0.35 × 0.30
Data collection
DiffractometerBruker SMART CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.971, 0.979
No. of measured, independent and
observed [I > 2σ(I)] reflections
8562, 1720, 1302
Rint0.052
(sin θ/λ)max1)0.606
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.043, 0.120, 1.04
No. of reflections1720
No. of parameters210
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.17, 0.14

Computer programs: SMART (Bruker, 1998), SAINT (Bruker, 1998), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6···Cg3i0.932.753.551 (3)145
C11—H11···Cg2i0.932.923.726 (3)146
Symmetry code: (i) x+3/2, y+1/2, z.
 

Acknowledgements

The authors thank the State Laboratory of Applied Organic Chemistry, Lanzhou University, for funding this study.

References

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