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Crystal structure, Hirshfeld surface analysis and inter­action energy and DFT studies of 1-methyl-3-(prop-2-yn-1-yl)-2,3-di­hydro-1H-1,3-benzo­diazol-2-one

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aLaboratoire de Chimie Organique Hétérocyclique URAC 21, Pôle de Compétence Pharmacochimie, Av. Ibn Battouta, BP 1014, Faculté des Sciences, Université Mohammed V, Rabat, Morocco, bDepartment of Physics, Hacettepe University, 06800 Beytepe, Ankara, Turkey, cDepartment of Chemistry, Tulane University, New Orleans, LA 70118, USA, and dLaboratoire de Chimie Appliquée et Environnement, Equipe de Chimie Bioorganique Appliquée, Faculté des Sciences, Université Ibn Zohr, Agadir, Morocco
*Correspondence e-mail: mohamedsrhir2018@gmail.com

Edited by A. J. Lough, University of Toronto, Canada (Received 12 November 2019; accepted 21 November 2019; online 29 November 2019)

In the title mol­ecule, C11H10N2O, the di­hydro­benzimidazol-2-one moiety is essentially planar, with the prop-2-yn-1-yl substituent rotated well out of this plane. In the crystal, C—HMthyπ(ring) inter­actions and C—HProp⋯ODhyr (Mthy = methyl, Prop = prop-2-yn-1-yl and Dhyr = di­hydro) hydrogen bonds form corrugated layers parallel to (10[\overline{1}]), which are associated through additional C—HBnz⋯ODhyr (Bnz = benzene) hydrogen bonds and head-to-tail, slipped, π-stacking [centroid-to-centroid distance = 3.7712 (7) Å] inter­actions between di­hydro­benzimidazol-2-one moieties. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions to the crystal packing are from H⋯H (44.1%), H⋯C/C⋯H (33.5%) and O⋯H/H⋯O (13.4%) inter­actions. Hydrogen-bonding and van der Waals inter­actions are the dominant inter­actions in the crystal packing. Computational chemistry calculations indicate that in the crystal, C—H⋯O hydrogen-bond energies are 46.8 and 32.5 (for C—HProp⋯ODhyr) and 20.2 (for C—HBnz⋯ODhyr) kJ mol−1. Density functional theory (DFT) optimized structures at the B3LYP/6–311 G(d,p) level are compared with the experimentally determined mol­ecular structure in the solid state. The HOMO–LUMO behaviour was elucidated to determine the energy gap.

1. Chemical context

Benzimidazole is an aromatic heterocyclic organic compound that plays an important role in medicinal chemistry and pharmacology. The most prominent benzimidazole moiety present in nature is N-ribosyl-di­methyl­benzimidazole and it serves as the axial ligand for cobalt in vitamin B12 (Walia et al., 2011[Walia, R., Hedaitullah, M., Naaz, S. F., Iqbal, K. & Lamba, H. S. (2011). Int. J. Res. Pharm. Chem. 1, 565-574.]). Benzimidazole derivatives possess many biological activities such as anti-microbial, anti-fungal, anti-histaminic, anti-inflammatory, anti-viral, anti-oxidant, anti-cancer and anti-ulcerative (Farukh & Mubashira, 2009[Farukh, A. & Mubashira, A. (2009). Eur. J. Med. Chem. 44, 834-844.]; Ayhan-Kılcıgil et al., 2007[Ayhan-Kılcıgil, G., Kus, G., Özdamar, E. D., Can-Eke, B. & Iscan, M. (2007). Arch. Pharm. Chem. Life Sci. 340, 607-611.]; Soderlind et al., 1999[Soderlind, K. J., Gorodetsky, B., Singh, A. K., Bachur, N., Miller, G. G. & Lown, J. W. (1999). Anticancer Drug. Des. 14, 19-36.]; Luo et al., 2011[Luo, Y., Yao, J. P., Yang, L., Feng, C. L., Tang, W., Wang, G. F., Zuo, J. P. & Lu, W. (2011). Arch. Pharm. Pharm. Med. Chem. 344, 78-83.]; Navarrete-Vázquez et al., 2011[Navarrete-Vázquez, G., Cedillo, R., Hernández-Campos, A., Yépez, L., Hernández-Luis, F., Valdez, J., Morales, R., Cortés, R., Hernández, M. & Castillo, R. (2011). Bioorg. Med. Chem. 11, 187-190.]). They are considered to be an important moiety for the development of mol­ecules of pharmaceutical inter­est (Mondieig et al., 2013[Mondieig, D., Lakhrissi, L., El Assyry, A., Lakhrissi, B., Negrier, P., Essassi, E. M., Massoui, M., Michel Leger, J. & Benali, B. (2013). J. Mar. Chim. Heterocycl. 12, 51-61.]; Lakhrissi et al., 2008[Lakhrissi, B., Benksim, A., Massoui, M., Essassi, E. M., Lequart, V., Joly, N., Beaupère, D., Wadouachi, A. & Martin, P. (2008). Carbohydr. Res. 343, 421-433.]). As a continuation of our research on the development of N-substituted benzimidazole derivatives and the evaluation of their potential pharmacological activities (Saber et al., 2018a[Saber, A., Sebbar, N. K., Hökelek, T., Hni, B., Mague, J. T. & Essassi, E. M. (2018a). Acta Cryst. E74, 1746-1750.],b[Saber, A., Sebbar, N. K., Hökelek, T., El hafi, M., Mague, J. T. & Essassi, E. M. (2018b). Acta Cryst. E74, 1842-1846.], 2020[Saber, A., Sebbar, N. K., Sert, Y., Alzaqri, N., Hökelek, T., El Ghayati, L., Talbaoui, A., Mague, J. T., Filali Baba, Y., Urrutigoîty, M. & Essassi, E. M. (2020). J. Mol. Struct. 1200, 127174.]; Ouzidan et al., 2011[Ouzidan, Y., Kandri Rodi, Y., Fronczek, F. R., Venkatraman, R., El Ammari, L. & Essassi, E. M. (2011). Acta Cryst. E67, o362-o363.]), we have studied the alkyl­ation reaction of iodo­methane with 1-(prop-2-yn­yl)-1H-benzoimidazol-2(3H)-one in the presence of tetra-n-butyl­ammonium bromide as catalyst and potassium carbonate as base, to give the title compound, I in good yield. We report herein on its synthesis, the mol­ecular and crystal structures along with the Hirshfeld surface analysis and the inter­molecular inter­action energies and the density functional theory (DFT) computational calculations carried out at the B3LYP/6–311 G(d,p) level for comparison with the experimentally determined mol­ecular structure in the solid state.

[Scheme 1]

2. Structural commentary

In the title compound, the di­hydro­benzimidazol-2-one moiety is planar to within 0.0160 (8) Å (r.m.s. deviation = 0.0082) with atom C7 deviating the most from the mean plane and a prop-2-yn-1-yl substituent rotated well out of this plane as shown by the C1—N2—C9—C10 torsion angle of 62.16 (13)° (Fig. 1[link]).

[Figure 1]
Figure 1
The mol­ecular structure of the title compound with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.

3. Supra­molecular features

In the crystal, inversion dimers are formed by pairs of C—HMthyCg1i inter­actions [Mthy = methyl; symmetry code: (i) − x, 1 − y, 1 − z; Cg1 is the centroid of the benzene (A; C1–C6), ring]; which are connected along the b-axis direction by C—HBnz⋯ODhyr hydrogen bonds (Bnz = benzene and Dhyr = di­hydro) and along the a-axis direction at ca 90° to this and parallel to (10[\overline{1}]) by inversion-related C—HProp⋯ODhyr hydrogen bonds (Table 1[link]). The resulting corrugated layers are parallel to (10[\overline{1}]) and are connected in pairs by slipped, head-to-tail π-stacking inter­actions between the di­hydro­benzimidazol-2-one moieties, [Cg2⋯Cg1ii = 3.7712 (7) Å, dihedral angle = 0.96 (6)°; symmetry code: (ii) 1 – x, 1 – y, 1 – z; Cg1 and Cg2 are the centroids of rings A and B (N1/N2/C1/C6/C7) and C—HProp⋯ODhyr (Prop = prop-2-yn-1-yl) hydrogen bonds (Table 1[link], Figs. 2[link] and 3[link]).

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the C1–C6 benzene ring.

D—H⋯A D—H H⋯A DA D—H⋯A
C3—H3⋯O1ix 1.005 (15) 2.566 (15) 3.4885 (15) 152.6 (11)
C8—H8CCg1v 1.004 (16) 2.626 (15) 3.5413 (13) 151.1 (12)
C9—H9B⋯O1vi 0.978 (15) 2.347 (15) 3.3198 (14) 172.9 (12)
C11—H11⋯O1vii 1.010 (15) 2.181 (15) 3.1569 (15) 162.1 (12)
Symmetry codes: (v) -x, -y+1, -z+1; (vi) [-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]; (vii) [-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]; (ix) x, y-1, z.
[Figure 2]
Figure 2
A partial packing diagram viewed along the a-axis direction with C—H⋯O hydrogen bonds, C—H⋯π(ring) and π-stacking inter­actions shown, respectively, by black, green and orange dashed lines.
[Figure 3]
Figure 3
A partial packing diagram viewed along the b-axis direction with inter­molecular inter­actions depicted as in Fig. 2[link].

4. Hirshfeld surface analysis

In order to visualize the inter­molecular inter­actions in the crystal of the title compound, a Hirshfeld surface (HS) analysis (Hirshfeld, 1977[Hirshfeld, H. L. (1977). Theor. Chim. Acta, 44, 129-138.]; Spackman & Jayatilaka, 2009[Spackman, M. A. & Jayatilaka, D. (2009). CrystEngComm, 11, 19-32.]) was carried out using Crystal Explorer 17.5 (Turner et al., 2017[Turner, M. J., McKinnon, J. J., Wolff, S. K., Grimwood, D. J., Spackman, P. R., Jayatilaka, D. & Spackman, M. A. (2017). CrystalExplorer17. The University of Western Australia.]). In the HS plotted over dnorm (Fig. 4[link]), the white surface indicates contacts with distances equal to the sum of van der Waals radii, and the red and blue colours indicate distances shorter (in close contact) or longer (distant contact) than the van der Waals radii, respectively (Venkatesan et al., 2016[Venkatesan, P., Thamotharan, S., Ilangovan, A., Liang, H. & Sundius, T. (2016). Spectrochim. Acta Part A, 153, 625-636.]). The bright-red spots appearing near O1 and the hydrogen atom H11 indicate their roles as the donors and/or acceptors, respectively; they also appear as blue and red regions corresponding to positive and negative potentials on the HS mapped over electrostatic potential (Spackman et al., 2008[Spackman, M. A., McKinnon, J. J. & Jayatilaka, D. (2008). CrystEngComm, 10, 377-388.]; Jayatilaka et al., 2005[Jayatilaka, D., Grimwood, D. J., Lee, A., Lemay, A., Russel, A. J., Taylor, C., Wolff, S. K., Cassam-Chenai, P. & Whitton, A. (2005). TONTO - A System for Computational Chemistry. Available at: https://hirshfeldsurface.net/]) as shown in Fig. 5[link]. The blue regions indicate positive electrostatic potential (hydrogen-bond donors), while the red regions indicate negative electrostatic potential (hydrogen-bond acceptors). The shape-index of the HS is a tool to visualize ππ stacking by the presence of adjacent red and blue triangles; if there are no adjacent red and/or blue triangles, then there are no ππ inter­actions. Fig. 6[link] clearly suggests that there are ππ inter­actions in (I)[link].

[Figure 4]
Figure 4
View of the three-dimensional Hirshfeld surface of the title compound plotted over dnorm in the range −0.3997 to 1.3219 a.u.
[Figure 5]
Figure 5
View of the three-dimensional Hirshfeld surface of the title compound plotted over electrostatic potential energy in the range −0.0500 to 0.0500 a.u. using the STO-3 G basis set at the Hartree–Fock level of theory. Hydrogen-bond donors and acceptors are shown as blue and red regions around the atoms corresponding to positive and negative potentials, respectively.
[Figure 6]
Figure 6
Hirshfeld surface of the title compound plotted over shape-index.

The overall two-dimensional fingerprint plot, Fig. 7[link]a, and those delineated into H⋯H, H⋯C/C⋯H, H⋯O/O ⋯ H, C⋯C, H⋯N/N⋯H and N⋯C/C⋯N contacts (McKinnon et al., 2007[McKinnon, J. J., Jayatilaka, D. & Spackman, M. A. (2007). Chem. Commun. pp. 3814-3816.]) are illustrated in Fig. 7[link]bg, respectively, together with their relative contributions to the Hirshfeld surface. The most important inter­action is H⋯H contributing 44.1% to the overall crystal packing, which is reflected in Fig. 7[link]b as widely scattered points of high density due to the large hydrogen content of the mol­ecule with the tip at de = di = 1.22 Å. The presence of C—H⋯π inter­actions gives rise to pairs of characteristic wings in the fingerprint plot delineated into H⋯C/C⋯H contacts, Fig. 7[link]c., contributing 33.5% to the HS (Table 2[link]); these are viewed as pairs of spikes with the tips at de + di = 2.56 Å. The pair of wings in Fig. 7[link]d has a symmetrical distribution of points with the edges at de + di = 2.09 Å arising from the H⋯O/O⋯H contacts (13.4% contribution). The C⋯C contacts, Fig. 7[link]e, have an arrow-shaped distribution of points with the tip at de = di = 1.75 Å. The H⋯N/N⋯N contacts, contributing 2.9% to the overall crystal packing, are depicted in Fig. 7[link]f as widely scattered points. Finally, the N⋯C/C⋯N inter­actions, contributing 2.4% to the overall crystal packing, are shown in Fig. 7[link]g as tiny characteristic wings with the tips at de + di = 3.45 Å.

Table 2
Selected interatomic distances (Å)

O1⋯H9A 2.491 (14) C11⋯O1vii 3.1569 (15)
O1⋯H3i 2.566 (15) C2⋯H8Aiv 2.82 (2)
O1⋯H8B 2.516 (19) C3⋯H8Cv 2.859 (15)
O1⋯H9Bii 2.346 (14) C3⋯H8Aiv 2.92 (2)
O1⋯H11iii 2.181 (15) C4⋯H8Cv 2.810 (15)
C2⋯C10 3.3889 (16) C5⋯H8Cv 2.935 (15)
C3⋯C8iv 3.5335 (17) C8⋯H5 2.983 (14)
C4⋯C8v 3.4947 (17) C9⋯H2 2.975 (14)
C4⋯C7iv 3.5437 (16) C10⋯H4viii 2.976 (15)
C5⋯C8v 3.5884 (17) C11⋯H5iv 2.865 (15)
C6⋯C6iv 3.5349 (14) C11⋯H4viii 2.705 (15)
C9⋯O1vi 3.3198 (14)    
Symmetry codes: (i) x, y+1, z; (ii) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{3\over 2}}]; (iii) [-x+{\script{3\over 2}}, y+{\script{1\over 2}}, -z+{\script{3\over 2}}]; (iv) -x+1, -y+1, -z+1; (v) -x, -y+1, -z+1; (vi) [-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]; (vii) [-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]; (viii) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z+{\script{1\over 2}}].
[Figure 7]
Figure 7
The full two-dimensional fingerprint plots for the title compound, showing (a) all inter­actions, and delineated into (b) H⋯H, (c) H⋯C/C⋯H, (d) H⋯O/O⋯H, (e) C⋯C, (f) H⋯N/N⋯H and (g) N⋯C/C⋯N inter­actions. The di and de values are the closest inter­nal and external distances (in Å) from given points on the Hirshfeld surface contacts.

The Hirshfeld surface representations with the function dnorm plotted onto the surface are shown for the H⋯H, H⋯C/C⋯H and H⋯O/O⋯H inter­actions in Fig. 8[link]ac, respectively.

[Figure 8]
Figure 8
The Hirshfeld surface representations with the function dnorm plotted onto the surface for (a) H⋯H, (b) H⋯C/C⋯H and (c) H⋯O/O⋯H inter­actions.

The Hirshfeld surface analysis confirms the importance of H-atom contacts in establishing the packing. The large number of H⋯H, H⋯C/C⋯H and H⋯ O/O⋯H inter­actions suggest that van der Waals inter­actions and hydrogen bonding play the major roles in the crystal packing (Hathwar et al., 2015[Hathwar, V. R., Sist, M., Jørgensen, M. R. V., Mamakhel, A. H., Wang, X., Hoffmann, C. M., Sugimoto, K., Overgaard, J. & Iversen, B. B. (2015). IUCrJ, 2, 563-574.]).

5. Inter­action energy calculations

The inter­molecular inter­action energies were calculated using the CE–B3LYP/6–31G(d,p) energy model available in CrystalExplorer17.5 (Turner et al., 2017[Turner, M. J., McKinnon, J. J., Wolff, S. K., Grimwood, D. J., Spackman, P. R., Jayatilaka, D. & Spackman, M. A. (2017). CrystalExplorer17. The University of Western Australia.]), where a cluster of mol­ecules is generated by applying crystallographic symmetry operations with respect to a selected central mol­ecule within the default radius of 3.8 Å (Turner et al., 2014[Turner, M. J., Grabowsky, S., Jayatilaka, D. & Spackman, M. A. (2014). J. Phys. Chem. Lett. 5, 4249-4255.]). The total inter­molecular energy (Etot) is the sum of electrostatic (Eele), polarization (Epol), dispersion (Edis) and exchange-repulsion (Erep) energies (Turner et al., 2015[Turner, M. J., Thomas, S. P., Shi, M. W., Jayatilaka, D. & Spackman, M. A. (2015). Chem. Commun. 51, 3735-3738.]) with scale factors of 1.057, 0.740, 0.871 and 0.618, respectively (Mackenzie et al., 2017[Mackenzie, C. F., Spackman, P. R., Jayatilaka, D. & Spackman, M. A. (2017). IUCrJ, 4, 575-587.]). Hydrogen-bonding inter­action energies (in kJ mol−1) were calculated to be −17.4 (Eele), −3.5 (Epol), −62.6 (Edis), 46.5 (Erep) and −46.8 (Etot) for C11—H11⋯O1, −12.4 (Eele), −1.9 (Epol), −41.6 (Edis), 29.6 (Erep) and −32.5 (Etot) for C9—H9B⋯O1 and −13.7 (Eele), −3.7 (Epol), −15.5 (Edis), 17.0 (Erep) and −20.2 (Etot) for C3—H3⋯O1.

6. DFT calculations

The optimized structure of the title compound in the gas phase was generated theoretically via density functional theory (DFT) using the standard B3LYP functional and 6–311 G(d,p) basis-set calculations (Becke, 1993[Becke, A. D. (1993). J. Chem. Phys. 98, 5648-5652.]) as implemented in GAUSSIAN 09 (Frisch et al., 2009[Frisch, M. J., et al. (2009). GAUSSIAN09. Gaussian Inc., Wallingford, CT, US]). The theoretical and experimental results are in good agreement (Table 3[link]). The highest-occupied mol­ecular orbital (HOMO), acting as an electron donor, and the lowest-unoccupied mol­ecular orbital (LUMO), acting as an electron acceptor, are very important parameters for quantum chemistry. When the energy gap is small, the mol­ecule is highly polarizable and has high chemical reactivity. The DFT calculations provide some important information on the reactivity and site selectivity of the mol­ecular framework. EHOMO and ELUMO clarify the inevitable charge-exchange collaboration inside the studied material and are given in Table 4[link] along with the electronegativity (χ), hardness (η), potential (μ), electrophilicity (ω) and softness (σ). The significance of η and σ is for the evaluation of both the reactivity and stability. The electron transition from the HOMO to the LUMO energy level is shown in Fig. 9[link]. The HOMO and LUMO are localized in the plane extending from the whole 1-methyl-3-(prop-2-yn-1-yl)-2,3-di­hydro-1H-1,3-benzo­diazol-2-one ring. The energy band gap [ΔE = ELUMOEHOMO] of the mol­ecule is about 5.4115 eV, and the frontier mol­ecular orbital energies, EHOMO and ELUMO are −5.8885 and −0.4770 eV, respectively.

Table 3
Comparison of the selected (X-ray and DFT) geometric data (Å, °)

Bonds/angles X-ray B3LYP/6–311 G(d,p)
O1—C7 1.2281 (13) 1.24660
N1—C7 1.3735 (14) 1.39764
N1—C6 1.3874 (15) 1.40100
N1—C8 1.4526 (14) 1.45375
N2—C7 1.3807 (14) 1.40268
N2—C1 1.3910 (13) 1.40222
N2—C9 1.4545 (14) 1.46036
C7—N1—C6 110.19 (9) 110.10303
C7—N1—C8 124.14 (10) 122.94288
C6—N1—C8 125.66 (10) 126.95366
C7—N2—C1 110.16 (9) 110.18664
C7—N2—C9 123.55 (9) 122.02491
C1—N2—C9 126.00 (9) 126.78733
C2—C1—N2 131.64 (10) 132.00719

Table 4
Calculated energies for the title compound

Mol­ecular Energy (a.u.) (eV)  
Total Energy TE (eV) −16594.1662
EHOMO (eV) −5.8885
ELUMO (eV) −0.4770
Energy gap, ΔE (eV) 5.4115
Dipole moment, μ (Debye) 2.8313
Ionization potential, I (eV) 5.8885
Electron affinity, A 2.6040
Electro negativity, χ 0.31828
Hardness, η 2.7058
Electrophilicity index, ω 1.8719
Softness, σ 0.3696
Fraction of electron transferred, ΔN 0.7054
[Figure 9]
Figure 9
The energy band gap of the title compound.

7. Database survey

The syntheses of several N-substituted benzimidazol-2-one analogues have been reported (Saber et al., 2018a[Saber, A., Sebbar, N. K., Hökelek, T., Hni, B., Mague, J. T. & Essassi, E. M. (2018a). Acta Cryst. E74, 1746-1750.],b[Saber, A., Sebbar, N. K., Hökelek, T., El hafi, M., Mague, J. T. & Essassi, E. M. (2018b). Acta Cryst. E74, 1842-1846.]; 2020[Saber, A., Sebbar, N. K., Sert, Y., Alzaqri, N., Hökelek, T., El Ghayati, L., Talbaoui, A., Mague, J. T., Filali Baba, Y., Urrutigoîty, M. & Essassi, E. M. (2020). J. Mol. Struct. 1200, 127174.]; Belaziz et al., 2012[Belaziz, D., Kandri Rodi, Y., Essassi, E. M. & El Ammari, L. (2012). Acta Cryst. E68, o1276.]; Bouayad et al., 2015[Bouayad, K., Kandri Rodi, Y., Ouzidan, Y., Essassi, E. M., Saadi, M. & El Ammari, L. (2015). Acta Cryst. E71, o735-o736.]; Belaziz et al., 2013[Belaziz, D., Kandri Rodi, Y., Ouazzani Chahdi, F., Essassi, E. M., Saadi, M. & El Ammari, L. (2013). Acta Cryst. E69, o122.]). In a search of the Cambridge Crystallographic Database (CSD; Version 5.40, update of September 2019; Groom et al., 2016[Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171-179.]) using benzimidazol-2-one with an exocyclic carbon atom bound to each nitro­gen generated 94 hits. In these, the bicyclic ring system is either planar, has a slight twist end-to-end, or, in the cases where the exocyclic substituents form a ring, has a very shallow bowl shape.

[Scheme 2]

The closest examples to the title compound, I, are II (HISFUN; Saber et al., 2018b[Saber, A., Sebbar, N. K., Hökelek, T., El hafi, M., Mague, J. T. & Essassi, E. M. (2018b). Acta Cryst. E74, 1842-1846.]), III (URAQAG; Ouzidan et al., 2011a[Ouzidan, Y., Kandri Rodi, Y., Jasinski, J. P., Butcher, R. J., Golen, J. A. & El Ammari, L. (2011a). Acta Cryst. E67, o1091.]) and IV (AGAXOX; Kandri Rodi et al., 2013[Kandri Rodi, Y., Misbahi, K., El-Ghayoury, A., Zorina, L., Essassi, E. M. & El Ammari, L. (2013). Acta Cryst. E69, o1159.]). In the title compound, the C—N bonds to the exocyclic groups are 1.4526 (14) and 1.4545 (19) Å while in IIIV the corresponding distances range from 1.445 (3) to 1.4632 (11) Å, and so are quite comparable. The exocyclic groups in I are in an anti-arrangement with the prop-2-yn-1-yl group rotated by 62.16 (13)° out of the plane of the bicyclic moiety (as measured by the C1—N2—C9—C10 torsion angle). In the other three, these substituents are also anti and in II the corresponding torsion angle is 73.46 (18)° while in III they are 82.58 (15) and 74.31 (14)°. In IV the torsion angles are 106.0 (3) and 113.4 (3)° indicating a rotation in the opposite direction from the first three.

8. Synthesis and crystallization

To a mixture of 1-(prop-2-yn­yl)-1H-benzimidazol-2(3H)-one (3.61 mmol), iodo­methane (6.73 mmol) and potassium carbonate (6.24 mmol) in DMF (15 ml) was added a catalytic amount of tetra-n-butyl­ammonium bromide (0.37 mmol). The mixture was stirred for 24 h. The solid material was removed by filtration and the solvent evaporated under vacuum. The solid product was purified by recrystallization from ethanol to afford colorless crystals (yield: in 82%).

9. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 5[link]. Hydrogen atoms were located in a difference Fourier map and refined freely.

Table 5
Experimental details

Crystal data
Chemical formula C11H10N2O
Mr 186.21
Crystal system, space group Monoclinic, P21/n
Temperature (K) 150
a, b, c (Å) 7.1507 (3), 8.8177 (4), 15.4602 (7)
β (°) 97.914 (2)
V3) 965.52 (7)
Z 4
Radiation type Cu Kα
μ (mm−1) 0.68
Crystal size (mm) 0.32 × 0.31 × 0.12
 
Data collection
Diffractometer Bruker D8 VENTURE PHOTON 100 CMOS
Absorption correction Multi-scan (SADABS; Krause et al., 2015[Krause, L., Herbst-Irmer, R., Sheldrick, G. M. & Stalke, D. (2015). J. Appl. Cryst. 48, 3-10.])
Tmin, Tmax 0.83, 0.92
No. of measured, independent and observed [I > 2σ(I)] reflections 6896, 1812, 1679
Rint 0.030
(sin θ/λ)max−1) 0.610
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.033, 0.086, 1.06
No. of reflections 1812
No. of parameters 168
H-atom treatment All H-atom parameters refined
Δρmax, Δρmin (e Å−3) 0.18, −0.19
Computer programs: APEX3 and SAINT (Bruker, 2016[Bruker (2016). APEX3, SAINT and SADABS. Bruker AXS, Inc., Madison, Wisconsin, USA.]), SHELXT (Sheldrick, 2015a[Sheldrick, G. M. (2015a). Acta Cryst. A71, 3-8.]), SHELXL2018 (Sheldrick, 2015b[Sheldrick, G. M. (2015b). Acta Cryst. C71, 3-8.]), DIAMOND (Brandenburg & Putz, 2012[Brandenburg, K. & Putz, H. (2012). DIAMOND. Crystal Impact GbR, Bonn, Germany.]) and SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Supporting information


Computing details top

Data collection: APEX3 (Bruker, 2016); cell refinement: SAINT (Bruker, 2016); data reduction: SAINT (Bruker, 2016); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2018 (Sheldrick, 2015b); molecular graphics: DIAMOND (Brandenburg & Putz, 2012); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

1-Methyl-3-(prop-2-yn-1-yl)-2,3-dihydro-1H-1,3-benzodiazol-2-one top
Crystal data top
C11H10N2OF(000) = 392
Mr = 186.21Dx = 1.281 Mg m3
Monoclinic, P21/nCu Kα radiation, λ = 1.54178 Å
a = 7.1507 (3) ÅCell parameters from 5848 reflections
b = 8.8177 (4) Åθ = 5.8–70.1°
c = 15.4602 (7) ŵ = 0.68 mm1
β = 97.914 (2)°T = 150 K
V = 965.52 (7) Å3Plate, colourless
Z = 40.32 × 0.31 × 0.12 mm
Data collection top
Bruker D8 VENTURE PHOTON 100 CMOS
diffractometer
1812 independent reflections
Radiation source: INCOATEC IµS micro-focus source1679 reflections with I > 2σ(I)
Mirror monochromatorRint = 0.030
Detector resolution: 10.4167 pixels mm-1θmax = 70.1°, θmin = 5.8°
ω scansh = 88
Absorption correction: multi-scan
(SADABS; Krause et al., 2015)
k = 109
Tmin = 0.83, Tmax = 0.92l = 1818
6896 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.033All H-atom parameters refined
wR(F2) = 0.086 w = 1/[σ2(Fo2) + (0.0402P)2 + 0.2239P]
where P = (Fo2 + 2Fc2)/3
S = 1.06(Δ/σ)max < 0.001
1812 reflectionsΔρmax = 0.18 e Å3
168 parametersΔρmin = 0.19 e Å3
0 restraintsExtinction correction: SHELXL2018 (Sheldrick, 2015b), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: dualExtinction coefficient: 0.0100 (12)
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
O10.31019 (11)0.82725 (9)0.64517 (6)0.0345 (2)
N10.24854 (12)0.64929 (11)0.53316 (6)0.0280 (2)
N20.36075 (12)0.56773 (10)0.66470 (6)0.0250 (2)
C10.33940 (14)0.44082 (11)0.61080 (7)0.0235 (2)
C20.37638 (15)0.28918 (12)0.62754 (8)0.0289 (3)
H20.426 (2)0.2543 (16)0.6872 (10)0.039 (4)*
C30.34025 (16)0.18941 (14)0.55731 (8)0.0353 (3)
H30.364 (2)0.0783 (17)0.5684 (10)0.043 (4)*
C40.27117 (17)0.24106 (15)0.47421 (8)0.0378 (3)
H40.246 (2)0.1678 (17)0.4255 (10)0.046 (4)*
C50.23359 (16)0.39392 (15)0.45751 (7)0.0339 (3)
H50.190 (2)0.4305 (16)0.3992 (10)0.042 (4)*
C60.26803 (14)0.49324 (12)0.52720 (7)0.0255 (3)
C70.30715 (14)0.69684 (12)0.61712 (7)0.0260 (2)
C80.17860 (17)0.75002 (16)0.46162 (8)0.0381 (3)
H8A0.255 (3)0.747 (2)0.4146 (13)0.076 (6)*
H8B0.176 (3)0.854 (2)0.4867 (13)0.072 (5)*
H8C0.044 (2)0.7264 (17)0.4370 (10)0.047 (4)*
C90.44506 (16)0.56993 (13)0.75585 (7)0.0283 (3)
H9A0.4344 (19)0.6753 (16)0.7764 (9)0.033 (3)*
H9B0.376 (2)0.5012 (16)0.7898 (9)0.038 (3)*
C100.64427 (15)0.52362 (12)0.76752 (7)0.0281 (3)
C110.80385 (17)0.48197 (14)0.77883 (8)0.0342 (3)
H110.938 (2)0.4443 (17)0.7926 (10)0.050 (4)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0298 (4)0.0254 (4)0.0471 (5)0.0006 (3)0.0015 (3)0.0012 (3)
N10.0239 (4)0.0309 (5)0.0277 (5)0.0020 (3)0.0012 (4)0.0074 (4)
N20.0254 (5)0.0249 (5)0.0236 (4)0.0005 (3)0.0007 (3)0.0007 (3)
C10.0196 (5)0.0264 (5)0.0244 (5)0.0023 (4)0.0028 (4)0.0014 (4)
C20.0249 (5)0.0281 (6)0.0337 (6)0.0008 (4)0.0041 (4)0.0011 (4)
C30.0298 (6)0.0300 (6)0.0469 (7)0.0021 (4)0.0088 (5)0.0072 (5)
C40.0339 (6)0.0427 (7)0.0384 (6)0.0083 (5)0.0107 (5)0.0158 (5)
C50.0286 (6)0.0486 (7)0.0248 (6)0.0089 (5)0.0048 (4)0.0032 (5)
C60.0207 (5)0.0307 (6)0.0254 (5)0.0046 (4)0.0037 (4)0.0014 (4)
C70.0189 (5)0.0261 (5)0.0328 (6)0.0007 (4)0.0025 (4)0.0025 (4)
C80.0294 (6)0.0450 (7)0.0380 (7)0.0013 (5)0.0019 (5)0.0189 (6)
C90.0296 (6)0.0332 (6)0.0218 (5)0.0004 (4)0.0019 (4)0.0014 (4)
C100.0333 (6)0.0293 (5)0.0206 (5)0.0018 (4)0.0004 (4)0.0014 (4)
C110.0330 (6)0.0381 (6)0.0298 (6)0.0022 (5)0.0016 (4)0.0030 (5)
Geometric parameters (Å, º) top
O1—C71.2281 (13)C4—C51.3915 (19)
N1—C71.3735 (14)C4—H40.989 (16)
N1—C61.3874 (15)C5—C61.3839 (16)
N1—C81.4526 (14)C5—H50.967 (15)
N2—C71.3807 (14)C8—H8A0.97 (2)
N2—C11.3910 (13)C8—H8B0.99 (2)
N2—C91.4545 (14)C8—H8C1.004 (16)
C1—C21.3805 (15)C9—C101.4689 (16)
C1—C61.4011 (14)C9—H9A0.988 (14)
C2—C31.3937 (17)C9—H9B0.978 (15)
C2—H20.991 (15)C10—C111.1885 (17)
C3—C41.3883 (19)C11—H111.009 (16)
C3—H31.005 (15)
O1···H9A2.491 (14)C11···O1vii3.1569 (15)
O1···H3i2.566 (15)C2···H8Aiv2.82 (2)
O1···H8B2.516 (19)C3···H8Cv2.859 (15)
O1···H9Bii2.346 (14)C3···H8Aiv2.92 (2)
O1···H11iii2.181 (15)C4···H8Cv2.810 (15)
C2···C103.3889 (16)C5···H8Cv2.935 (15)
C3···C8iv3.5335 (17)C8···H52.983 (14)
C4···C8v3.4947 (17)C9···H22.975 (14)
C4···C7iv3.5437 (16)C10···H4viii2.976 (15)
C5···C8v3.5884 (17)C11···H5iv2.865 (15)
C6···C6iv3.5349 (14)C11···H4viii2.705 (15)
C9···O1vi3.3198 (14)
C7—N1—C6110.19 (9)C5—C6—N1132.12 (10)
C7—N1—C8124.14 (10)C5—C6—C1120.83 (11)
C6—N1—C8125.66 (10)N1—C6—C1107.04 (9)
C7—N2—C1110.16 (9)O1—C7—N1127.43 (10)
C7—N2—C9123.55 (9)O1—C7—N2126.43 (10)
C1—N2—C9126.00 (9)N1—C7—N2106.14 (9)
C2—C1—N2131.64 (10)N1—C8—H8A112.7 (12)
C2—C1—C6121.90 (10)N1—C8—H8B106.7 (11)
N2—C1—C6106.45 (9)H8A—C8—H8B111.1 (16)
C1—C2—C3117.07 (11)N1—C8—H8C111.9 (9)
C1—C2—H2120.7 (8)H8A—C8—H8C108.5 (15)
C3—C2—H2122.3 (8)H8B—C8—H8C105.7 (13)
C4—C3—C2121.20 (11)N2—C9—C10112.38 (9)
C4—C3—H3120.5 (9)N2—C9—H9A106.5 (8)
C2—C3—H3118.3 (9)C10—C9—H9A109.8 (8)
C3—C4—C5121.63 (11)N2—C9—H9B109.9 (8)
C3—C4—H4119.6 (9)C10—C9—H9B108.2 (8)
C5—C4—H4118.8 (9)H9A—C9—H9B110.1 (11)
C6—C5—C4117.35 (11)C11—C10—C9177.63 (12)
C6—C5—H5120.9 (8)C10—C11—H11176.1 (9)
C4—C5—H5121.7 (8)
C7—N2—C1—C2178.91 (11)C2—C1—C6—C50.69 (15)
C9—N2—C1—C24.89 (17)N2—C1—C6—C5178.96 (9)
C7—N2—C1—C60.69 (11)C2—C1—C6—N1179.67 (9)
C9—N2—C1—C6174.72 (9)N2—C1—C6—N10.02 (11)
N2—C1—C2—C3179.33 (10)C6—N1—C7—O1179.51 (10)
C6—C1—C2—C30.23 (15)C8—N1—C7—O10.13 (17)
C1—C2—C3—C40.37 (16)C6—N1—C7—N21.13 (11)
C2—C3—C4—C50.54 (18)C8—N1—C7—N2179.49 (9)
C3—C4—C5—C60.08 (17)C1—N2—C7—O1179.51 (10)
C4—C5—C6—N1179.20 (11)C9—N2—C7—O15.31 (16)
C4—C5—C6—C10.52 (15)C1—N2—C7—N11.12 (11)
C7—N1—C6—C5178.10 (11)C9—N2—C7—N1175.32 (9)
C8—N1—C6—C51.27 (18)C7—N2—C9—C10111.11 (11)
C7—N1—C6—C10.72 (11)C1—N2—C9—C1062.16 (13)
C8—N1—C6—C1179.91 (9)
Symmetry codes: (i) x, y+1, z; (ii) x+1/2, y+1/2, z+3/2; (iii) x+3/2, y+1/2, z+3/2; (iv) x+1, y+1, z+1; (v) x, y+1, z+1; (vi) x+1/2, y1/2, z+3/2; (vii) x+3/2, y1/2, z+3/2; (viii) x+1/2, y+1/2, z+1/2.
Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the C1–C6 benzene ring.
D—H···AD—HH···AD···AD—H···A
C3—H3···O1ix1.005 (15)2.566 (15)3.4885 (15)152.6 (11)
C8—H8C···Cg1v1.004 (16)2.626 (15)3.5413 (13)151.1 (12)
C9—H9B···O1vi0.978 (15)2.347 (15)3.3198 (14)172.9 (12)
C11—H11···O1vii1.010 (15)2.181 (15)3.1569 (15)162.1 (12)
Symmetry codes: (v) x, y+1, z+1; (vi) x+1/2, y1/2, z+3/2; (vii) x+3/2, y1/2, z+3/2; (ix) x, y1, z.
Comparison of the selected (X-ray and DFT) geometric data (Å, °) top
Bonds/anglesX-rayB3LYP/6-311 G(d,p)
O1—C71.2281 (13)1.24660
N1—C71.3735 (14)1.39764
N1—C61.3874 (15)1.40100
N1—C81.4526 (14)1.45375
N2—C71.3807 (14)1.40268
N2—C11.3910 (13)1.40222
N2—C91.4545 (14)1.46036
C7—N1—C6110.19 (9)110.10303
C7—N1—C8124.14 (10)122.94288
C6—N1—C8125.66 (10)126.95366
C7—N2—C1110.16 (9)110.18664
C7—N2—C9123.55 (9)122.02491
C1—N2—C9126.00 (9)126.78733
C2—C1—N2131.64 (10)132.00719
Calculated energies for the title compound top
Molecular Energy (a.u.) (eV)
Total Energy TE (eV)-16594.1662
EHOMO (eV)-5.8885
ELUMO (eV)-0.4770
Energy gap, ΔE (eV)5.4115
Dipole moment, µ (Debye)2.8313
Ionization potential, I (eV)5.8885
Electron affinity, A2.6040
Electro negativity, χ0.31828
Hardness, η2.7058
Electrophilicity index, ω1.8719
Softness, σ0.3696
Fraction of electron transferred, ΔN0.7054
 

Funding information

The support of NSF–MRI grant No. 1228232 for the purchase of the diffractometer and Tulane University for support of the Tulane Crystallography Laboratory are gratefully acknowledged. TH is grateful to Hacettepe University Scientific Research Project Unit (grant No. 013 D04 602 004).

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