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CHEMISTRY
ISSN: 2053-2296

1-(6-Amino-1,3-benzodioxol-5-yl)-3-(4-pyrid­yl)prop-2-en-1-one crystallizes with Z′ = 2: hydrogen-bonded supra­molecular substructures in one and two dimensions, each containing only one type of mol­ecule

CROSSMARK_Color_square_no_text.svg

aGrupo de Investigación de Compuestos Heterocíclicos, Departamento de Química, Universidad de Valle, AA 25360 Cali, Colombia, bDepartamento de Química Inorgánica y Orgánica, Universidad de Jaén, 23071 Jaén, Spain, cDepartment of Chemistry, University of Aberdeen, Meston Walk, Old Aberdeen AB24 3UE, Scotland, and dSchool of Chemistry, University of St Andrews, Fife KY16 9ST, Scotland
*Correspondence e-mail: cg@st-andrews.ac.uk

(Received 13 December 2006; accepted 20 December 2006; online 13 January 2007)

The title compound, C15H12N2O3, crystallizes with Z′ = 2 in the space group P[\overline{1}] and the intra­molecular dimensions show evidence for a polarized mol­ecular–electronic structure. Each of the two independent types of mol­ecule forms its own hydrogen-bonded supra­molecular substructure, and these are entirely different from one another: one type of mol­ecule forms a chain of edge-fused rings, while the other type forms sheets.

Comment

Intra­molecular cyclization of 2-amino-Z-chalcones is nowadays one of the most expeditious methods for the synthesis of the biologically significant 2-aryl-2,3-dihydro­quinolin-4(1H)-ones (Ahmed & van Lier, 2006[Ahmed, N. & van Lier, J. (2006). Tetrahedron Lett. 47, 2725-2729.], 2007[Ahmed, N. & van Lier, J. (2007). Tetrahedron Lett. 48, 13-15.]; Low, Cobo, Cuervo et al., 2004[Low, J. N., Cobo, J., Cuervo, P., Abonia, R. & Glidewell, C. (2004). Acta Cryst. C60, o827-o829.]). We report here the mol­ecular and supra­molecular structure of the title compound, (I)[link], as a new example of this class of compound. We have recently reported the structures of the analogues (II)[link]–(VI)[link] (see scheme), which all exhibit completely different modes of supra­molecular aggregation (Low et al., 2002[Low, J. N., Cobo, J., Nogueras, M., Sánchez, A., Albornoz, A. & Abonia, R. (2002). Acta Cryst. C58, o42-o45.]; Low, Cobo, Nogueras et al., 2004[Low, J. N., Cobo, J., Nogueras, M., Cuervo, P., Abonia, R. & Glidewell, C. (2004). Acta Cryst. C60, o744-o750.]). In compound (I)[link], the supra­molecular structure proves to be different from all examples previously studied.

Compound (I)[link] crystallizes with Z′ = 2 in the space group P[\overline{1}]. The two independent mol­ecules (Fig. 1[link]) are both nearly planar, as shown by the leading torsion angles (Table 1[link]), with the sole exception of the five-membered rings, which both adopt envelope conformations folded across the O⋯O vectors. The ring-puckering parameters φ (Cremer & Pople, 1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]) for the atom sequences O1n, Cn2, On3, Cn3a, Cn7a (where n = 1 or 2) are 212.2 (6)° when n = 1 and 30.6 (5)° when n = 2, so that the two mol­ecules within the selected asymmetric unit are approximately mirror images of one another.

[Scheme 1]

The bond distances in the two independent mol­ecules are very similar (Table 1[link]) and they provide evidence for significant bond fixation within the aminoaryl rings. For example, the Cn3a—Cn4 and Cn7—Cn7a bonds (where n = 1 or 2) are all short, while the Cn5—Cn6 and Cn6—Cn7 bonds are all long. In addition, the Cn6—Cn8 bonds are short for their type, while the Cn8—On8 bonds are long. This pattern of behaviour closely mimics that in compounds (II)[link]–(VI)[link] and indicates the importance of the charge-separated form A as an important contributor to the overall mol­ecular-electronic structure, alongside the delocalized form B.

In each of the two mol­ecules of (I)[link], there is an intra­molecular N—H⋯O hydrogen bond (Table 2[link]). The actions of the inter­molecular hydrogen bonds generate two entirely different substructures, one composed solely of type 1 mol­ecules and other entirely of type 2 mol­ecules. In the type 1 substructure, amino atom N15 in the type 1 mol­ecule at (x, y, z) acts as hydrogen-bond donor to pyridyl atom N114 in the type 1 mol­ecule at (x, 1 + y, 1 + z), so generating by translation a C(11) chain (Bernstein et al., 1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]) running parallel to the [011] direction. In addition, aryl atom C116 at (x, y, z) acts as hydrogen-bond donor to carbonyl atom O18 in the type 1 mol­ecule at (1 − x, 2 − y, 1 − z), so generating by inversion an R22(14) ring centred at ([{1 \over 2}], 1, [{1 \over 2}]). The combination of these two motifs then generates a chain of edge-fused rings along [011], with R22(14) rings centred at ([{1 \over 2}], n, n − [{1 \over 2}]) (n = zero or integer), and R44(20) rings, alternatively described as R64(16) rings if the intra­molecular hydrogen bond is included, centred at ([{1 \over 2}], n + [{1 \over 2}], n) (n = zero or integer) (Fig. 2[link]).

In contrast with the one-dimensional substructure formed by the type 1 mol­ecules, the substructure built from type 2 mol­ecules is two-dimensional. Atom N25 in the type 2 mol­ecule at (x, y, z) acts as hydrogen-bond donor to pyridyl atom N214 in the type 2 mol­ecule at (x, 1 + y, 1 + z), so forming by translation a C(11) chain along [011], exactly analogous to that formed by the type 1 mol­ecules. In addition, atom C22 at (x, y, z) acts as hydrogen-bond donor to carbonyl atom O28 in the type 2 mol­ecule at (−1 + x, y, z), so generating by translation a C(8) chain running parallel to the [100] direction. The combination of the [100] and [011] chains generates a sheet lying parallel to (01[\overline{1}]) and containing equal numbers of S(6) and R54(33) rings (Fig. 3[link]).

Thus, the two types of mol­ecule in compound (I)[link] form substructures which are entirely different. There are no direction-specific inter­actions between adjacent chains of type 1 mol­ecules, or between adjacent sheets of type 2 mol­ecules, nor are there any direction-specific inter­actions between the two different substructures. Instead, the type 1 chains simply lie between pairs of type 2 sheets.

Two other members of this series also crystallize with Z′ = 2. In compound (V)[link] (Low et al., 2002[Low, J. N., Cobo, J., Nogueras, M., Sánchez, A., Albornoz, A. & Abonia, R. (2002). Acta Cryst. C58, o42-o45.]), the two independent mol­ecules are linked by N—H⋯O hydrogen bonds to form cyclic centrosymmetric tetra­mers containing two mol­ecules of each type, and the tetra­mers are further linked into chains by C—H⋯O hydrogen bonds. Compound (III)[link] exhibits concomitant polymorphism as it crystallizes from solution in dimethyl­formamide as a mixture of monoclinic (Z′ = 1) and triclinic (Z′ = 2) crystals (Low, Cobo, Nogueras et al., 2004[Low, J. N., Cobo, J., Nogueras, M., Cuervo, P., Abonia, R. & Glidewell, C. (2004). Acta Cryst. C60, o744-o750.]). In the polymorph having Z′ = 2, one type of mol­ecule forms a simple chain and the other type is pendent from it. Neither of compounds (III)[link] and (V)[link] with Z′ = 2 contains two distinct substructures analogous to those found here in compound (I)[link].

For none of compounds (I)[link]–(V)[link], which differ only in the identity of a single substitution in an aryl ring, could the supra­molecular structure of any single example be reliably predicted from a detailed knowledge of the supra­molecular structures of the remainder. Not even the type of direction-specific inter­molecular inter­action manifest in each structure is readily predictable. The wide range of supra­molecular structures observed in this series, combined on the one hand with the occurrence of two completely distinct and independent substructures formed by the two independent mol­ecules in compound (I)[link] and, on the other, with the occurrence of concomitant polymorphism in compound (III)[link], together present a very keen challenge to the attempted prediction from first principles of the crystal structures, dominated by weak direction-specific inter­molecular forces, of simple mol­ecular compounds, an endeavour where convincing success is still elusive (Lommerse et al., 2000[Lommerse, J. P. M., Motherwell, W. D. S., Ammon, H. L., Dunitz, J. D., Gavezzotti, A., Hofmann, D. W. M., Leusen, F. J. J., Mooij, W. T. M., Price, S. L., Schweizer, B., Schmidt, M. U., van Eijck, B. P., Verwer, P. & Williams, D. E. (2000). Acta Cryst. B56, 697-714.]; Motherwell et al., 2002[Motherwell, W. D. S., Ammon, H. L., Dunitz, J. D., Dzyabchenko, A., Erk, P., Gavezzotti, A., Hofmann, D. W. M., Leusen, F. J. J., Lommerse, J. P. M., Mooij, W. T. M., Price, S. L., Scheraga, H., Schweizer, B., Schmidt, M. U., van Eijck, B. P., Verwer, P. & Williams, D. E. (2002). Acta Cryst. B58, 647-661.]; Day et al., 2005[Day, G. M. et al. (2005). Acta Cryst. B61, 511-527.]).

[Figure 1]
Figure 1
The two independent mol­ecules of compound (I)[link], showing the atom-labelling scheme for (a) a type 1 mol­ecule and (b) a type 2 mol­ecule. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii.
[Figure 2]
Figure 2
A stereoview of part of the crystal structure of compound (I)[link], showing the formation of a chain of edge-fused rings along [011] containing only type 1 mol­ecules.
[Figure 3]
Figure 3
A stereoview of part of the crystal structure of compound (I)[link], showing the formation of a sheet parallel to (01[\overline{1}]) containing only type 2 mol­ecules.

Experimental

A solution in ethanol (10 ml) of 6-amino-3,4-methyl­enedioxy­acetophenone (2.8 mmol), pyridine-4-carbaldehyde (2.8 mmol) and aqueous sodium hydroxide solution (0.5 ml of a 20% solution) was stirred at room temperature for 3 h. The precipitate thus formed was collected by filtration and washed with ethanol, yielding compound (I)[link] as an orange solid (yield 70%; m.p. 469 K). MS (70 eV) m/e (%): 268 (50, [M]+), 190 (100, [M − C5H4N]+). Crystals suitable for single-crystal X-ray diffraction were grown from a solution in ethanol.

Crystal data
  • C15H12N2O3

  • Mr = 268.27

  • Triclinic, [P \overline 1]

  • a = 10.1044 (3) Å

  • b = 11.7533 (5) Å

  • c = 12.1655 (5) Å

  • α = 117.232 (2)°

  • β = 97.480 (3)°

  • γ = 99.585 (2)°

  • V = 1231.11 (9) Å3

  • Z = 4

  • Dx = 1.447 Mg m−3

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 120 (2) K

  • Lath, orange

  • 0.44 × 0.38 × 0.07 mm

Data collection
  • Bruker–Nonius KappaCCD area-detector diffractometer

  • φ and ω scans

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2003[Sheldrick, G. M. (2003). SADABS. Version 2.10. University of Göttingen, Germany.]) Tmin = 0.967, Tmax = 0.993

  • 28373 measured reflections

  • 5675 independent reflections

  • 3599 reflections with I > 2σ(I)

  • Rint = 0.067

  • θmax = 27.7°

Refinement
  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.059

  • wR(F2) = 0.169

  • S = 1.03

  • 5675 reflections

  • 361 parameters

  • H-atom parameters constrained

  • w = 1/[σ2(Fo2) + (0.0873P)2 + 0.3836P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max < 0.001

  • Δρmax = 0.25 e Å−3

  • Δρmin = −0.30 e Å−3

Table 1
Selected geometric parameters (Å, °)

C13a—C14 1.364 (3) 
C14—C15 1.427 (3)
C15—C16 1.428 (3)
C16—C17 1.425 (3)
C17—C17a 1.357 (3)
C17a—C13a 1.390 (3)
C15—N15 1.356 (3)
C16—C18 1.459 (3)
C18—O18 1.242 (3)
C23a—C24 1.353 (3)
C24—C25 1.426 (3)
C25—C26 1.428 (3)
C26—C27 1.426 (3)
C27—C27a 1.354 (3)
C27a—C23a 1.394 (3)
C25—N25 1.351 (3)
C26—C28 1.467 (3)
C28—O28 1.242 (2)
C15—C16—C18—C19 176.55 (19)
C16—C18—C19—C110 −152.2 (2)
C18—C19—C110—C111 −179.3 (2)
C19—C110—C111—C112 9.0 (4)
C25—C26—C28—C29 171.38 (18)
C26—C28—C29—C210 165.6 (2)
C28—C29—C210—C211 179.56 (19)
C29—C210—C211—C212 2.8 (3)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N15—H15A⋯O18 0.96 1.90 2.657 (3) 134
N15—H15B⋯N114i 0.96 2.09 3.054 (3) 179
C116—H116⋯O18ii 0.95 2.55 3.430 (3) 154
N25—H25A⋯O28 0.96 1.94 2.662 (2) 130
N25—H25B⋯N214i 0.96 2.04 2.996 (3) 176
C22—H22A⋯O28iii 0.99 2.41 3.270 (3) 145
Symmetry codes: (i) x, y+1, z+1; (ii) -x+1, -y+2, -z+1; (iii) x-1, y, z.

Crystals of compound (I)[link] are triclinic. The space group P[\overline{1}] was selected and confirmed by the structure analysis. All H atoms were located in difference maps and then treated as riding atoms, with C—H = 0.95 (aromatic and alkenic) or 0.99 Å (CH2) and N—H = 0.96 Å, and with Uiso(H) = 1.2Ueq(C,N).

Data collection: COLLECT (Nonius, 1999[Nonius (1999). COLLECT. Nonius BV, Delft, The Netherlands.]); cell refinement: DENZO (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]) and COLLECT; data reduction: DENZO and COLLECT; program(s) used to solve structure: OSCAIL (McArdle, 2003[McArdle, P. (2003). OSCAIL for Windows. Version 10. Crystallography Centre, Chemistry Department, NUI Galway, Ireland.]) and SHELXS97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXL97. University of Göttingen, Germany.]); program(s) used to refine structure: OSCAIL and SHELXL97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXL97. University of Göttingen, Germany.]); molecular graphics: PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]); software used to prepare material for publication: SHELXL97 and PRPKAPPA (Ferguson, 1999[Ferguson, G. (1999). PRPKAPPA. University of Guelph, Canada.]).

Supporting information


Comment top

Intramolecular cyclization of 2-amino-Z-chalcones is nowadays one of the most expeditious methods for the synthesis of the biologically significant 2-aryl-2,3-dihydroquinolin-4(1H)-ones (Ahmed & van Lier, 2006, 2007; Low, Cobo, Cuervo et al., 2004). Here, we report the molecular and supramolecular structure of the title compound, (I), as a new example of this class of compound. We have recently reported the structures of the analogues (II)–(VI), which all exhibit completely different modes of supramolecular aggregation (Low et al., 2002; Low, Cobo, Nogueras et al., 2004). In compound (I), the supramolecular structure proves to be different from all examples previously studied.

Compound (I) crystallizes with Z' = 2 in space group P1. The two independent molecules (Fig. 1) are both nearly planar, as shown by the leading torsion angles (Table 1), with the sole exception of the five-membered rings, which both adopt envelope conformations folded across the O···O vectors. The ring-puckering parameters ϕ (Cremer & Pople, 1975) for the atom sequences O1n, Cn2, On3, Cn3a, Cn7a (where n = 1 or 2) are 212.2 (6)° when n = 1 and 30.6 (5)° when n = 2, so that the two molecules within the selected asymmetric unit are approximately mirror images of one another.

The bond distances in the two independent molecules are very similar (Table 1) and they provide evidence for significant bond fixation within the aminoaryl rings. For example, the Cn3a—Cn4 and Cn7—Cn7a bonds (where n = 1 or 2) are all short, while the Cn5—Cn6 and Cn6—Cn7 bonds are all long. In addition, the Cn6—Cn8 bonds are short for their type, while the Cn8—On8 bonds are long. This pattern of behaviour closely mimics that in compounds (II)–(VI) and indicates the importance of the charge-separated form (A) as an important contributor to the overall molecular-electronic structure, alongside the delocalized form (B).

In each of the two molecules of (I), there is an intramolecular N—H···O hydrogen bond (Table 2). The actions of the intermolecular hydrogen bonds generate two entirely different sub-structures, one composed solely of type 1 molecules and other entirely of type 2 molecules. In the type 1 sub-structure, amino atom N15 in the type 1 molecule at (x, y, z) acts as hydrogen-bond donor to pyridyl atom N114 in the type 1 molecule at (x, 1 + y, 1 + z), so generating by translation a C(11) chain (Bernstein et al., 1995) running parallel to the [011] direction. In addition, aryl atom C116 at (x, y, z) acts as hydrogen-bond donor to carbonyl atom O18 in the type 1 molecule at (1 - x, 2 - y, 1 - z), so generating by inversion an R22(14) ring centred at (1/2, 1, 1/2). The combination of these two motifs then generates a chain of edge-fused rings along [011], with R22(14) rings centred at (1/2, n, n - 1/2) (n = zero or integer), and R44(20) rings, alternatively described as R46(16) rings if the intramolecular hydrogen bond is included, centred at (1/2, n + 1/2, n) (n = zero or integer) (Fig. 2).

In contrast with the one-dimensional sub-structure formed by the type 1 molecules, the sub-structure built from type 2 molecules is two dimensional. Atom N25 in the type 2 molecule at (x, y, z) acts as hydrogen-bond donor to the pyridyl atom N214 in the type 2 molecule at (x, 1 + y, 1 + z), so forming by translation a C(11) chain along [011], exactly analogous to that formed by the type 1 molecules. In addition, atom C22 at (x, y, z) acts as hydrogen-bond donor to carbonyl atom O28 in the type 2 molecule at (-1 + x, y, z), so generating by translation a C(8) chain running parallel to the [100] direction. The combination of the [100] and [011] chains generates a sheet lying parallel to (011) and containing equal numbers of S(6) and R45(33) rings (Fig. 3).

Thus, the two types of molecule in compound (I) form sub-structures which are entirely different. There are no direction-specific interactions between adjacent chains of type 1 molecules, or between adjacent sheets of type 2 molecules, nor are there any direction-specific interactions between the two different sub-structures. Instead, the type 1 chains simply lie between pairs of type 2 sheets.

Two other members of this series also crystallize with Z' = 2. In compound (V) (Low et al., 2002), the two independent molecules are linked by N—H···O hydrogen bonds to form cyclic centrosymmetric tetramers containing two molecules of each type, and the tetramers are further linked into chains by C—H···O hydrogen bonds. Compound (III) exhibits concomitant polymorphism as it crystallizes from solution in dimethylformamide as a mixture of monoclinic (Z' = 1) and triclinic (Z' = 2) crystals (Low, Cobo, Cuervo et al., 2004 or Low, Cobo, Nogueras et al., 2004?). In the polymorph having Z' = 2, one type of molecule forms a simple chain and the other type is pendent from it. Neither of these compounds, (III) and (V), with Z' = 2 contains two distinct sub-structures analogous to those found here in compound (I).

For none of the compounds (I)–(V), which differ only in the identity of a single substitution in an aryl ring, could the supramolecular structure of any single example be reliably predicted from a detailed knowledge of the supramolecular structures of the remainder. Not even the type of direction-specific intermolecular interaction manifest in each structure is readily predictable. The wide range of supramolecular structures observed in this series, combined on the one hand with the occurrence of two completely distinct and independent sub-structures formed by the two independent molecules in compound (I) and, on the other, with the occurrence of concomitant polymorphism in compound (III), together present a very keen challenge to the attempted prediction from first principles of the crystal structures, dominated by weak direction-specific intermolecular forces, of simple molecular compounds, an endeavour where convincing success is still elusive (Lommerse et al., 2000; Motherwell et al., 2002; Day et al., 2005).

Related literature top

For related literature, see: Ahmed & van Lier (2006, 2007); Bernstein et al. (1995); Cremer & Pople (1975); Day et al. (2005); Lommerse et al. (2000); Low et al. (2002); Low, Cobo, Cuervo, Abonia & Glidewell (2004); Low, Cobo, Nogueras, Cuervo, Abonia & Glidewell (2004); Motherwell et al. (2002).

Experimental top

A solution in ethanol (10 ml) of 6-amino-3,4-methylenedioxyacetophenone (2.8 mmol) and pyridine-4-carbaldehyde (2.8 mmol), and aqueous sodium hydroxide solution (0.5 ml of a 20% solution), was stirred at room temperature for 3 h. The precipitate thus formed was collected by filtration and washed with ethanol, yielding compound (I) as an orange solid (yield 70%; m.p. 469 K). MS (70 eV) m/e (%) 268 (50, [M]+), 190 (100, [M - C5H4N]+). Crystals suitable for single-crystal X-ray diffraction were grown from a solution in ethanol.

Refinement top

Crystals of compound (I) are triclinic. Space group P1 was selected and confirmed by the structure analysis. All H atoms were located in difference maps and then treated as riding atoms, with C—H = 0.95 (aromatic and alkenic) or 0.99 Å (CH2) and N—H = 0.96 Å, and with Uiso(H) = 1.2Ueq(C,N).

Computing details top

Data collection: COLLECT (Nonius, 1999); cell refinement: DENZO (Otwinowski & Minor, 1997) and COLLECT; data reduction: DENZO and COLLECT; program(s) used to solve structure: OSCAIL (McArdle, 2003) and SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: OSCAIL and SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97 and PRPKAPPA (Ferguson, 1999).

Figures top
[Figure 1] Fig. 1. The two independent molecules of compound (I), showing the atom-labelling scheme. (a) A type 1 molecule. (b) A type 2 molecule. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii.
[Figure 2] Fig. 2. A stereoview of part of the crystal structure of compound (I), showing the formation of a chain of edge-fused rings along [011] containing only type 1 molecules.
[Figure 3] Fig. 3. A stereoview of part of the crystal structure of compound (I), showing the formation of a sheet parallel to (011) containing only type 2 molecules.
1-(6-Amino-1,3-benzodioxol-5-yl)-3-(4-pyridyl)prop-2-en-1-one top
Crystal data top
C15H12N2O3Z = 4
Mr = 268.27F(000) = 560
Triclinic, P1Dx = 1.447 Mg m3
Hall symbol: -P 1Melting point: 469 K
a = 10.1044 (3) ÅMo Kα radiation, λ = 0.71073 Å
b = 11.7533 (5) ÅCell parameters from 5675 reflections
c = 12.1655 (5) Åθ = 2.0–27.7°
α = 117.232 (2)°µ = 0.10 mm1
β = 97.480 (3)°T = 120 K
γ = 99.585 (2)°Lath, orange
V = 1231.11 (9) Å30.44 × 0.38 × 0.07 mm
Data collection top
Bruker Nonius KappaCCD area-detector
diffractometer
5675 independent reflections
Radiation source: Bruker-Nonius FR591 rotating anode3599 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.067
Detector resolution: 9.091 pixels mm-1θmax = 27.7°, θmin = 2.0°
ϕ and ω scansh = 1213
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
k = 1515
Tmin = 0.967, Tmax = 0.993l = 1515
28373 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)] = 0.059Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.169H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.0873P)2 + 0.3836P]
where P = (Fo2 + 2Fc2)/3
5675 reflections(Δ/σ)max < 0.001
361 parametersΔρmax = 0.25 e Å3
0 restraintsΔρmin = 0.30 e Å3
Crystal data top
C15H12N2O3γ = 99.585 (2)°
Mr = 268.27V = 1231.11 (9) Å3
Triclinic, P1Z = 4
a = 10.1044 (3) ÅMo Kα radiation
b = 11.7533 (5) ŵ = 0.10 mm1
c = 12.1655 (5) ÅT = 120 K
α = 117.232 (2)°0.44 × 0.38 × 0.07 mm
β = 97.480 (3)°
Data collection top
Bruker Nonius KappaCCD area-detector
diffractometer
5675 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
3599 reflections with I > 2σ(I)
Tmin = 0.967, Tmax = 0.993Rint = 0.067
28373 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0590 restraints
wR(F2) = 0.169H-atom parameters constrained
S = 1.03Δρmax = 0.25 e Å3
5675 reflectionsΔρmin = 0.30 e Å3
361 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O110.14597 (16)0.81061 (15)0.70775 (15)0.0336 (4)
C120.1572 (3)0.8620 (2)0.8368 (2)0.0379 (6)
O130.11094 (16)1.00477 (15)0.89636 (15)0.0344 (4)
C13a0.0283 (2)1.0269 (2)0.8237 (2)0.0285 (5)
C140.0586 (2)1.1432 (2)0.8505 (2)0.0286 (5)
C150.1316 (2)1.1420 (2)0.7573 (2)0.0280 (5)
N150.2151 (2)1.25811 (18)0.78232 (18)0.0348 (5)
C160.1142 (2)1.0217 (2)0.6418 (2)0.0263 (5)
C170.0209 (2)0.9043 (2)0.6197 (2)0.0275 (5)
C17a0.0468 (2)0.9100 (2)0.7107 (2)0.0273 (5)
C180.1968 (2)1.0156 (2)0.5502 (2)0.0272 (5)
O180.28357 (17)1.11338 (15)0.56612 (15)0.0361 (4)
C190.1813 (2)0.8862 (2)0.4339 (2)0.0283 (5)
C1100.2840 (2)0.8611 (2)0.3773 (2)0.0316 (5)
C1110.2807 (2)0.7381 (2)0.2616 (2)0.0302 (5)
C1120.1604 (2)0.6391 (2)0.1879 (2)0.0344 (5)
C1130.1676 (3)0.5260 (2)0.0821 (2)0.0368 (6)
N1140.2830 (2)0.50550 (19)0.04332 (18)0.0349 (5)
C1150.3984 (3)0.6020 (2)0.1142 (2)0.0348 (5)
C1160.4018 (2)0.7177 (2)0.2222 (2)0.0337 (5)
O210.00445 (14)0.43558 (15)0.60453 (15)0.0323 (4)
C220.0560 (2)0.5410 (2)0.6742 (2)0.0369 (6)
O230.03442 (15)0.62087 (16)0.79995 (15)0.0353 (4)
C23a0.1615 (2)0.5987 (2)0.7828 (2)0.0266 (5)
C240.2862 (2)0.6683 (2)0.8646 (2)0.0277 (5)
C250.4051 (2)0.6289 (2)0.8240 (2)0.0247 (5)
N250.53018 (18)0.70101 (18)0.90334 (17)0.0305 (4)
C260.3890 (2)0.51655 (19)0.70231 (19)0.0229 (4)
C270.2543 (2)0.4463 (2)0.6218 (2)0.0254 (5)
C27a0.1449 (2)0.4892 (2)0.6636 (2)0.0252 (5)
C280.5102 (2)0.4786 (2)0.6557 (2)0.0247 (5)
O280.63014 (14)0.54780 (15)0.71139 (14)0.0298 (4)
C290.4877 (2)0.3505 (2)0.5372 (2)0.0284 (5)
C2100.5845 (2)0.3201 (2)0.4734 (2)0.0266 (5)
C2110.5699 (2)0.1955 (2)0.3567 (2)0.0258 (5)
C2120.4470 (2)0.0968 (2)0.2976 (2)0.0351 (6)
C2130.4398 (3)0.0163 (2)0.1869 (2)0.0400 (6)
N2140.5456 (2)0.03995 (19)0.13096 (18)0.0357 (5)
C2150.6631 (2)0.0542 (2)0.1887 (2)0.0325 (5)
C2160.6800 (2)0.1721 (2)0.3004 (2)0.0302 (5)
H11A0.09870.82860.88100.045*
H11B0.25410.83500.84020.045*
H140.07001.22200.92840.034*
H15A0.26741.25400.72070.042*
H15B0.23751.33530.86490.042*
H170.00630.82350.54280.033*
H190.09580.82090.40010.034*
H1100.36800.92860.41450.038*
H1120.07450.64870.20970.041*
H1130.08450.45850.03380.044*
H1150.48250.59040.08890.042*
H1160.48670.78290.26920.040*
H22A0.14930.50500.67950.044*
H22B0.06420.59490.63170.044*
H240.29420.74090.94630.033*
H25A0.61130.67870.87510.037*
H25B0.53340.78150.97840.037*
H270.24160.37120.54070.030*
H290.40050.28800.50620.034*
H2100.67070.38430.50580.032*
H2120.36870.10730.33330.042*
H2130.35440.08200.14750.048*
H2150.74010.04020.15150.039*
H2160.76660.23600.33790.036*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O110.0344 (9)0.0272 (8)0.0312 (9)0.0022 (7)0.0088 (7)0.0093 (7)
C120.0463 (14)0.0303 (13)0.0322 (13)0.0075 (11)0.0141 (11)0.0108 (11)
O130.0385 (9)0.0299 (9)0.0311 (9)0.0085 (7)0.0148 (7)0.0103 (7)
C13a0.0293 (11)0.0296 (12)0.0255 (11)0.0114 (10)0.0079 (9)0.0111 (10)
C140.0340 (12)0.0224 (12)0.0205 (11)0.0095 (10)0.0050 (9)0.0030 (9)
C150.0298 (11)0.0237 (11)0.0250 (11)0.0079 (9)0.0043 (9)0.0076 (10)
N150.0467 (12)0.0205 (10)0.0243 (10)0.0016 (9)0.0119 (9)0.0018 (8)
C160.0262 (11)0.0227 (11)0.0225 (11)0.0071 (9)0.0042 (9)0.0051 (9)
C170.0283 (11)0.0228 (11)0.0221 (11)0.0081 (9)0.0036 (9)0.0036 (9)
C17a0.0264 (11)0.0231 (11)0.0280 (12)0.0057 (9)0.0048 (9)0.0096 (10)
C180.0275 (11)0.0241 (12)0.0230 (11)0.0055 (10)0.0039 (9)0.0066 (10)
O180.0401 (9)0.0259 (9)0.0291 (9)0.0023 (7)0.0127 (7)0.0038 (7)
C190.0320 (12)0.0228 (11)0.0212 (11)0.0059 (9)0.0053 (9)0.0043 (9)
C1100.0312 (12)0.0269 (12)0.0224 (11)0.0039 (10)0.0032 (9)0.0025 (10)
C1110.0346 (12)0.0277 (12)0.0222 (11)0.0096 (10)0.0057 (9)0.0071 (10)
C1120.0340 (12)0.0311 (13)0.0265 (12)0.0105 (10)0.0059 (10)0.0044 (10)
C1130.0389 (13)0.0283 (13)0.0293 (13)0.0073 (11)0.0020 (11)0.0048 (11)
N1140.0461 (12)0.0311 (11)0.0220 (10)0.0156 (10)0.0070 (9)0.0068 (9)
C1150.0411 (13)0.0333 (13)0.0263 (12)0.0148 (11)0.0119 (11)0.0087 (11)
C1160.0345 (12)0.0332 (13)0.0273 (12)0.0090 (10)0.0077 (10)0.0096 (11)
O210.0209 (8)0.0297 (9)0.0307 (9)0.0051 (6)0.0030 (6)0.0035 (7)
C220.0279 (12)0.0367 (13)0.0306 (13)0.0123 (10)0.0026 (10)0.0036 (11)
O230.0241 (8)0.0380 (9)0.0304 (9)0.0114 (7)0.0073 (7)0.0045 (8)
C23a0.0250 (11)0.0256 (11)0.0254 (11)0.0086 (9)0.0084 (9)0.0082 (10)
C240.0297 (11)0.0235 (11)0.0202 (11)0.0074 (9)0.0047 (9)0.0030 (9)
C250.0238 (10)0.0210 (11)0.0234 (11)0.0042 (9)0.0045 (9)0.0070 (9)
N250.0250 (9)0.0251 (10)0.0250 (10)0.0055 (8)0.0039 (8)0.0003 (8)
C260.0241 (10)0.0189 (10)0.0204 (10)0.0048 (8)0.0060 (8)0.0056 (9)
C270.0273 (11)0.0186 (10)0.0219 (11)0.0039 (9)0.0040 (9)0.0043 (9)
C27a0.0205 (10)0.0223 (11)0.0248 (11)0.0026 (9)0.0024 (9)0.0067 (9)
C280.0242 (11)0.0242 (11)0.0236 (11)0.0057 (9)0.0062 (9)0.0101 (9)
O280.0222 (8)0.0291 (8)0.0262 (8)0.0038 (7)0.0046 (6)0.0051 (7)
C290.0242 (11)0.0221 (11)0.0268 (12)0.0033 (9)0.0046 (9)0.0034 (9)
C2100.0255 (11)0.0252 (11)0.0229 (11)0.0049 (9)0.0044 (9)0.0076 (10)
C2110.0287 (11)0.0239 (11)0.0206 (11)0.0091 (9)0.0045 (9)0.0070 (9)
C2120.0274 (12)0.0296 (13)0.0321 (13)0.0065 (10)0.0076 (10)0.0019 (11)
C2130.0339 (13)0.0295 (13)0.0364 (14)0.0057 (11)0.0063 (11)0.0010 (11)
N2140.0392 (11)0.0308 (11)0.0295 (11)0.0151 (9)0.0081 (9)0.0066 (9)
C2150.0338 (12)0.0332 (13)0.0275 (12)0.0137 (11)0.0114 (10)0.0098 (11)
C2160.0302 (11)0.0295 (12)0.0267 (12)0.0094 (10)0.0087 (9)0.0094 (10)
Geometric parameters (Å, º) top
O11—C17a1.390 (3)O21—C27a1.396 (2)
O11—C121.430 (3)O21—C221.433 (3)
C12—O131.448 (3)C22—O231.447 (3)
C12—H11A0.99C22—H22A0.99
C12—H11B0.99C22—H22B0.99
O13—C13a1.370 (3)O23—C23a1.376 (3)
C13a—C141.364 (3)C23a—C241.353 (3)
C14—C151.427 (3)C24—C251.426 (3)
C15—C161.428 (3)C25—C261.428 (3)
C16—C171.425 (3)C26—C271.426 (3)
C17—C17a1.357 (3)C27—C27a1.354 (3)
C17a—C13a1.390 (3)C27a—C23a1.394 (3)
C14—H140.95C24—H240.95
C15—N151.356 (3)C25—N251.351 (3)
N15—H15A0.9599N25—H25A0.9599
N15—H15B0.96N25—H25B0.96
C16—C181.459 (3)C26—C281.467 (3)
C17—H170.95C27—H270.95
C18—O181.242 (3)C28—O281.242 (2)
C18—C191.494 (3)C28—C291.487 (3)
C19—C1101.319 (3)C29—C2101.322 (3)
C19—H190.95C29—H290.95
C110—C1111.477 (3)C210—C2111.467 (3)
C110—H1100.95C210—H2100.95
C111—C1121.388 (3)C211—C2161.382 (3)
C111—C1161.390 (3)C211—C2121.389 (3)
C112—C1131.385 (3)C212—C2131.375 (3)
C112—H1120.95C212—H2120.95
C113—N1141.332 (3)C213—N2141.341 (3)
C113—H1130.95C213—H2130.95
N114—C1151.339 (3)N214—C2151.327 (3)
C115—C1161.384 (3)C215—C2161.391 (3)
C115—H1150.95C215—H2150.95
C116—H1160.95C216—H2160.95
C17a—O11—C12104.08 (17)C27a—O21—C22103.21 (16)
O11—C12—O13106.63 (17)O21—C22—O23106.73 (17)
O11—C12—H11A110.4O21—C22—H22A110.4
O13—C12—H11A110.4O23—C22—H22A110.4
O11—C12—H11B110.4O21—C22—H22B110.4
O13—C12—H11B110.4O23—C22—H22B110.4
H11A—C12—H11B108.6H22A—C22—H22B108.6
C13a—O13—C12104.61 (17)C23a—O23—C22104.26 (16)
C14—C13a—O13128.0 (2)C24—C23a—O23127.80 (19)
C14—C13a—C17a122.4 (2)C24—C23a—C27a122.97 (19)
O13—C13a—C17a109.52 (19)O23—C23a—C27a109.23 (18)
C13a—C14—C15117.59 (19)C23a—C24—C25117.72 (19)
C13a—C14—H14121.2C23a—C24—H24121.1
C15—C14—H14121.2C25—C24—H24121.1
N15—C15—C14117.67 (19)N25—C25—C24117.98 (19)
N15—C15—C16122.13 (19)N25—C25—C26122.32 (18)
C14—C15—C16120.19 (19)C24—C25—C26119.70 (19)
C15—N15—H15A116.2C25—N25—H25A118.8
C15—N15—H15B121.7C25—N25—H25B117.3
H15A—N15—H15B120.6H25A—N25—H25B122.9
C17—C16—C15119.13 (19)C27—C26—C25119.58 (18)
C17—C16—C18119.66 (19)C27—C26—C28119.66 (18)
C15—C16—C18121.09 (19)C25—C26—C28120.62 (18)
C17a—C17—C16118.7 (2)C27a—C27—C26118.51 (19)
C17a—C17—H17120.6C27a—C27—H27120.7
C16—C17—H17120.6C26—C27—H27120.7
C17—C17a—O11128.7 (2)C27—C27a—C23a121.49 (19)
C17—C17a—C13a121.9 (2)C27—C27a—O21129.09 (19)
O11—C17a—C13a109.30 (18)C23a—C27a—O21109.37 (17)
O18—C18—C16122.81 (19)O28—C28—C26122.98 (19)
O18—C18—C19117.69 (19)O28—C28—C29118.84 (18)
C16—C18—C19119.46 (18)C26—C28—C29118.17 (18)
C110—C19—C18121.2 (2)C210—C29—C28122.5 (2)
C110—C19—H19119.4C210—C29—H29118.7
C18—C19—H19119.4C28—C29—H29118.7
C19—C110—C111126.2 (2)C29—C210—C211125.4 (2)
C19—C110—H110116.9C29—C210—H210117.3
C111—C110—H110116.9C211—C210—H210117.3
C112—C111—C116117.0 (2)C216—C211—C212117.03 (19)
C112—C111—C110123.0 (2)C216—C211—C210120.53 (19)
C116—C111—C110120.0 (2)C212—C211—C210122.44 (19)
C113—C112—C111119.0 (2)C213—C212—C211119.3 (2)
C113—C112—H112120.5C213—C212—H212120.3
C111—C112—H112120.5C211—C212—H212120.3
N114—C113—C112124.4 (2)N214—C213—C212124.2 (2)
N114—C113—H113117.8N214—C213—H213117.9
C112—C113—H113117.8C212—C213—H213117.9
C113—N114—C115116.22 (19)C215—N214—C213116.1 (2)
N114—C115—C116123.5 (2)N214—C215—C216123.7 (2)
N114—C115—H115118.2N214—C215—H215118.1
C116—C115—H115118.2C216—C215—H215118.1
C115—C116—C111119.8 (2)C211—C216—C215119.6 (2)
C115—C116—H116120.1C211—C216—H216120.2
C111—C116—H116120.1C215—C216—H216120.2
C17a—O11—C12—O1323.8 (2)C27a—O21—C22—O2326.5 (2)
O11—C12—O13—C13a23.0 (2)O21—C22—O23—C23a25.2 (2)
C12—O13—C13a—C14168.3 (2)C22—O23—C23a—C24166.1 (2)
C12—O13—C13a—C17a13.2 (2)C22—O23—C23a—C27a13.9 (2)
O13—C13a—C14—C15178.2 (2)O23—C23a—C24—C25178.0 (2)
C17a—C13a—C14—C150.1 (3)C27a—C23a—C24—C251.9 (3)
C13a—C14—C15—N15178.3 (2)C23a—C24—C25—N25177.55 (19)
C13a—C14—C15—C160.9 (3)C23a—C24—C25—C262.1 (3)
N15—C15—C16—C17177.7 (2)N25—C25—C26—C27178.58 (19)
C14—C15—C16—C171.5 (3)C24—C25—C26—C271.0 (3)
N15—C15—C16—C186.2 (3)N25—C25—C26—C283.0 (3)
C14—C15—C16—C18174.59 (19)C24—C25—C26—C28176.60 (19)
C15—C16—C17—C17a1.2 (3)C25—C26—C27—C27a0.3 (3)
C18—C16—C17—C17a174.90 (19)C28—C26—C27—C27a175.32 (19)
C16—C17—C17a—O11176.9 (2)C26—C27—C27a—C23a0.6 (3)
C16—C17—C17a—C13a0.4 (3)C26—C27—C27a—O21178.0 (2)
C12—O11—C17a—C17167.2 (2)C24—C23a—C27a—C270.6 (3)
C12—O11—C17a—C13a15.9 (2)O23—C23a—C27a—C27179.35 (19)
C14—C13a—C17a—C170.1 (3)C24—C23a—C27a—O21177.3 (2)
O13—C13a—C17a—C17178.75 (19)O23—C23a—C27a—O212.7 (2)
C14—C13a—C17a—O11176.97 (19)C22—O21—C27a—C27164.1 (2)
O13—C13a—C17a—O111.6 (2)C22—O21—C27a—C23a18.2 (2)
C17—C16—C18—O18177.3 (2)C27—C26—C28—O28167.84 (19)
C15—C16—C18—O181.3 (3)C25—C26—C28—O287.7 (3)
C17—C16—C18—C190.5 (3)C27—C26—C28—C2913.1 (3)
C15—C16—C18—C19176.55 (19)C25—C26—C28—C29171.38 (18)
O18—C18—C19—C11025.7 (3)O28—C28—C29—C21015.3 (3)
C16—C18—C19—C110152.2 (2)C26—C28—C29—C210165.6 (2)
C18—C19—C110—C111179.3 (2)C28—C29—C210—C211179.56 (19)
C19—C110—C111—C1129.0 (4)C29—C210—C211—C216177.4 (2)
C19—C110—C111—C116171.2 (2)C29—C210—C211—C2122.8 (3)
C116—C111—C112—C1131.2 (3)C216—C211—C212—C2131.2 (3)
C110—C111—C112—C113178.9 (2)C210—C211—C212—C213178.6 (2)
C111—C112—C113—N1141.4 (4)C211—C212—C213—N2140.8 (4)
C112—C113—N114—C1150.7 (3)C212—C213—N214—C2150.1 (4)
C113—N114—C115—C1160.1 (3)C213—N214—C215—C2160.2 (3)
N114—C115—C116—C1110.2 (4)C212—C211—C216—C2150.9 (3)
C112—C111—C116—C1150.5 (3)C210—C211—C216—C215178.9 (2)
C110—C111—C116—C115179.7 (2)N214—C215—C216—C2110.2 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N15—H15A···O180.961.902.657 (3)134
N15—H15B···N114i0.962.093.054 (3)179
C116—H116···O18ii0.952.553.430 (3)154
N25—H25A···O280.961.942.662 (2)130
N25—H25B···N214i0.962.042.996 (3)176
C22—H22A···O28iii0.992.413.270 (3)145
Symmetry codes: (i) x, y+1, z+1; (ii) x+1, y+2, z+1; (iii) x1, y, z.

Experimental details

Crystal data
Chemical formulaC15H12N2O3
Mr268.27
Crystal system, space groupTriclinic, P1
Temperature (K)120
a, b, c (Å)10.1044 (3), 11.7533 (5), 12.1655 (5)
α, β, γ (°)117.232 (2), 97.480 (3), 99.585 (2)
V3)1231.11 (9)
Z4
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.44 × 0.38 × 0.07
Data collection
DiffractometerBruker Nonius KappaCCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2003)
Tmin, Tmax0.967, 0.993
No. of measured, independent and
observed [I > 2σ(I)] reflections
28373, 5675, 3599
Rint0.067
(sin θ/λ)max1)0.655
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.059, 0.169, 1.03
No. of reflections5675
No. of parameters361
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.25, 0.30

Computer programs: COLLECT (Nonius, 1999), DENZO (Otwinowski & Minor, 1997) and COLLECT, DENZO and COLLECT, OSCAIL (McArdle, 2003) and SHELXS97 (Sheldrick, 1997), OSCAIL and SHELXL97 (Sheldrick, 1997), PLATON (Spek, 2003), SHELXL97 and PRPKAPPA (Ferguson, 1999).

Selected geometric parameters (Å, º) top
C13a—C141.364 (3)C23a—C241.353 (3)
C14—C151.427 (3)C24—C251.426 (3)
C15—C161.428 (3)C25—C261.428 (3)
C16—C171.425 (3)C26—C271.426 (3)
C17—C17a1.357 (3)C27—C27a1.354 (3)
C17a—C13a1.390 (3)C27a—C23a1.394 (3)
C15—N151.356 (3)C25—N251.351 (3)
C16—C181.459 (3)C26—C281.467 (3)
C18—O181.242 (3)C28—O281.242 (2)
C15—C16—C18—C19176.55 (19)C25—C26—C28—C29171.38 (18)
C16—C18—C19—C110152.2 (2)C26—C28—C29—C210165.6 (2)
C18—C19—C110—C111179.3 (2)C28—C29—C210—C211179.56 (19)
C19—C110—C111—C1129.0 (4)C29—C210—C211—C2122.8 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N15—H15A···O180.961.902.657 (3)134
N15—H15B···N114i0.962.093.054 (3)179
C116—H116···O18ii0.952.553.430 (3)154
N25—H25A···O280.961.942.662 (2)130
N25—H25B···N214i0.962.042.996 (3)176
C22—H22A···O28iii0.992.413.270 (3)145
Symmetry codes: (i) x, y+1, z+1; (ii) x+1, y+2, z+1; (iii) x1, y, z.
 

Acknowledgements

X-ray data were collected at the EPSRC National Crystallography Service, University of Southampton, England. JC thanks the Consejería de Innovación, Ciencia y Empresa (Junta de Andalucía, Spain) and the Universidad de Jaén for financial support. PC and RA thank COLCIENCIAS and UNIVALLE (Universidad del Valle, Colombia) for financial support; RA also thanks AUIP for supporting a research trip to Universidad de Jaén.

References

First citationAhmed, N. & van Lier, J. (2006). Tetrahedron Lett. 47, 2725–2729.  Web of Science CrossRef CAS Google Scholar
First citationAhmed, N. & van Lier, J. (2007). Tetrahedron Lett. 48, 13–15.  Web of Science CrossRef CAS Google Scholar
First citationBernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555–1573.  CrossRef CAS Web of Science Google Scholar
First citationCremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354–1358.  CrossRef CAS Web of Science Google Scholar
First citationDay, G. M. et al. (2005). Acta Cryst. B61, 511–527.  Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
First citationFerguson, G. (1999). PRPKAPPA. University of Guelph, Canada.  Google Scholar
First citationLommerse, J. P. M., Motherwell, W. D. S., Ammon, H. L., Dunitz, J. D., Gavezzotti, A., Hofmann, D. W. M., Leusen, F. J. J., Mooij, W. T. M., Price, S. L., Schweizer, B., Schmidt, M. U., van Eijck, B. P., Verwer, P. & Williams, D. E. (2000). Acta Cryst. B56, 697–714.  Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
First citationLow, J. N., Cobo, J., Cuervo, P., Abonia, R. & Glidewell, C. (2004). Acta Cryst. C60, o827–o829.  Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
First citationLow, J. N., Cobo, J., Nogueras, M., Cuervo, P., Abonia, R. & Glidewell, C. (2004). Acta Cryst. C60, o744–o750.  Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
First citationLow, J. N., Cobo, J., Nogueras, M., Sánchez, A., Albornoz, A. & Abonia, R. (2002). Acta Cryst. C58, o42–o45.  CSD CrossRef CAS IUCr Journals Google Scholar
First citationMcArdle, P. (2003). OSCAIL for Windows. Version 10. Crystallography Centre, Chemistry Department, NUI Galway, Ireland.  Google Scholar
First citationMotherwell, W. D. S., Ammon, H. L., Dunitz, J. D., Dzyabchenko, A., Erk, P., Gavezzotti, A., Hofmann, D. W. M., Leusen, F. J. J., Lommerse, J. P. M., Mooij, W. T. M., Price, S. L., Scheraga, H., Schweizer, B., Schmidt, M. U., van Eijck, B. P., Verwer, P. & Williams, D. E. (2002). Acta Cryst. B58, 647–661.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationNonius (1999). COLLECT. Nonius BV, Delft, The Netherlands.  Google Scholar
First citationOtwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307–326. New York: Academic Press.  Google Scholar
First citationSheldrick, G. M. (1997). SHELXL97. University of Göttingen, Germany.  Google Scholar
First citationSheldrick, G. M. (2003). SADABS. Version 2.10. University of Göttingen, Germany.  Google Scholar
First citationSpek, A. L. (2003). J. Appl. Cryst. 36, 7–13.  Web of Science CrossRef CAS IUCr Journals Google Scholar

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