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Crystal structure, Hirshfeld surface analysis and inter­action energy and DFT studies of 2-(2,3-di­hydro-1H-perimidin-2-yl)-6-meth­­oxy­phenol

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aLaboratoire de Chimie Organique Heterocyclique URAC 21, Pôle de Competence Pharmacochimie, Faculté des Sciences, Universite Mohammed V, Rabat, Morocco, bLaboratoire de Chimie Organique et de Substances Naturelles, UFR Sciences des Structures de la Matière et Technologie, Université Félix Houphouët-Boigny, 22 BP 582 Abidjan, Côte d'Ivoire, cDepartment of Physics, Hacettepe University, 06800 Beytepe, Ankara, Turkey, dLaboratoire de Thermodynamique et Physicochimie du Milieu, Université Nangui Abrogoua, UFR-SFA, 02 BP 801 Abidjan 02, Côte d'Ivoire, eLaboratoire de Cristallographie et Physique Moléculaire, UFR SSMT, Université Félix Houphouët Boigny, 01 BP V34 Abidjan 01, Côte d'Ivoire, and fUFR des Sciences Biologiques, Université Péléforo Gon Coulibaly, BP 1328 Korhogo, Côte d'Ivoire
*Correspondence e-mail: daoudaballo526@gmail.com

Edited by A. J. Lough, University of Toronto, Canada (Received 10 March 2020; accepted 29 March 2020; online 3 April 2020)

The title compound, C18H16N2O2, consists of perimidine and meth­oxy­phenol units, where the tricyclic perimidine unit contains a naphthalene ring system and a non-planar C4N2 ring adopting an envelope conformation with the NCN group hinged by 47.44 (7)° with respect to the best plane of the other five atoms. In the crystal, O—HPhnl⋯NPrmdn and N—HPrmdn⋯OPhnl (Phnl = phenol and Prmdn = perimidine) hydrogen bonds link the mol­ecules into infinite chains along the b-axis direction. Weak C—H⋯π inter­actions may further stabilize the crystal structure. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (49.0%), H⋯C/C⋯H (35.8%) and H⋯O/O⋯H (12.0%) inter­actions. Hydrogen bonding and van der Waals inter­actions are the dominant inter­actions in the crystal packing. Computational chemistry indicates that in the crystal, the O—HPhnl⋯NPrmdn and N—HPrmdn⋯OPhnl hydrogen-bond energies are 58.4 and 38.0 kJ mol−1, respectively. 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

Six-membered heterocyclic compounds carrying two nitro­gen atoms have been widely studied (Aly & El-Shaieb, 2004[Aly, A. A. & El-Shaieb, K. M. (2004). Tetrahedron, 60, 3797-3802.]; Koca et al., 2012[Koca, I., ngren, H., Kýbrýz, E. & Yýlmaz, F. (2012). Dyes Pigments, 95, 421-426.]; Zhao et al., 2012[Zhao, J.-F., Liu, Y., Soh, J. B., Li, Y.-X., Ganguly, R., Ye, K.-Q., Huo, F., Huang, L., Tok, A. L. Y., Loo, J. S. C. & Zhang, Q. (2012). Tetrahedron Lett. 53, 6044-6047.]; Baranov & Fadeev, 2016[Baranov, D. S. & Fadeev, D. S. (2016). Mendeleev Commun. 26, 174-176.]; Lahmidi et al., 2018[Lahmidi, S., Sebbar, N. K., Hökelek, T., Chkirate, K., Mague, J. T. & Essassi, E. M. (2018). Acta Cryst. E74, 1833-1837.]). Perimidine derivatives (peri­naphtho-fused perimidine ring systems) in particular have aroused a lot of inter­est because of their applications in photophysics (Del Valle et al., 1997[Del Valle, J. C., Catalán, J., Foces-Foces, C., Llamas-Saiz, A. L., Elguero, J., Sanz, D., Dotor, J. & Claramunt, R. M. (1997). J. Lumin. 75, 17-26.]) and their use as colouring matters for polyester fibers (Claramunt et al., 1995[Claramunt, R. M., Dotor, J. & Elguero, J. (1995). Ann. Quim. 91, 151-183.]) and as fluorescent materials (Varsha et al., 2010[Varsha, G., Arun, V., Robinson, P. P., Sebastian, M., Varghese, D., Leeju, P., Jayachandran, V. P. & Yusuff, K. M. M. (2010). Tetrahedron Lett. 51, 2174-2177.]). These mol­ecules have a wide range of biological applications (Dzieduszycka et al., 2002[Dzieduszycka, M., Martelli, S., Arciemiuk, M., Bontemps-Gracz, M. M., Kupiec, A. & Borowski, E. (2002). Bioorg. Med. Chem. 10, 1025-1035.]), indicating that the perimidine group is a potentially useful model in medicinal chemistry research and therapeutic applications. In coordination chemistry, perimidine derivatives have been studied for their inter­esting catalytic activities (Cucciolito et al., 2013a[Cucciolito, M. E., Panunzi, B., Ruffo, F. & Tuzi, A. (2013a). Tetrahedron Lett. 54, 1503-1506.]; Akıncı et al., 2014[Akıncı, P. A., Gülcemal, S., Kazheva, O. N., Alexandrov, G. G., Dyachenko, O. A., Çetinkaya, E. & Çetinkaya, B. (2014). J. Organomet. Chem. 765, 23-30.]) as well as in the field of corrosion inhibition (He et al., 2018[He, X., Mao, J., Ma, Q. & Tang, Y. (2018). J. Mol. Liq. 269, 260-268.]). As a continuation of our research on the development of new perimidine derivatives with potential pharmacological applications, we studied the condensation reaction of ortho-vanillin and 1,8-di­aminona­phthalene in ether under agitation at room temperature, which gave the title compound, 2-(2,3-di­hydro-1H-perimidin-2-yl)-6-meth­oxy­phenol, in good yield. We report herein the synthesis, the mol­ecular and crystal structures along with Hirshfeld surface analysis and computational calculations of the title compound, (I)[link].

[Scheme 1]

2. Structural commentary

The title compound, (I)[link], consists of perimidine and meth­oxy­phenol units, where the tricyclic perimidine unit contains a naphthalene ring system and a non-planar C4N2 ring (Fig. 1[link]). A puckering analysis of the non-planar six-membered C4N2, B (N1/N2/C1/C9–C11), ring gave the parameters q2 = 0.3879 (12) Å, q3 = −0.2565 (12) Å, QT = 0.4650 (13) Å, θ2 = 123.47 (15)° and φ2 = 235.98 (18)°]. The ring adopts an envelope conformation, where atom C1 is at the flap position and at a distance of 0.6454 (12) Å from the best plane through the other five atoms. The C4N2 ring is hinged about the N⋯N vector with the N1—C1—N2 plane being inclined by 47.44 (7)° to the best plane of the other five atoms (N1/N2/C9–C11). In the meth­oxy­phenol moiety, the C8—O2—C4—C5 and C8—O2—C4—C3 torsion angles are −2.9 (2)° and 176.72 (12)°, respectively. Rings A (C2–C7), C (C10–C15) and D (C9/C10/C15–C18) are oriented at dihedral angles of A/C = 65.39 (4)°, A/D = 69.63 (4)° and C/D = 4.31 (3)°.

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

3. Supra­molecular features

In the crystal, O—HPhnl⋯NPrmdn and N—HPrmdn⋯OPhnl (Phnl = phenol and Prmdn = perimidine) hydrogen bonds (Table 1[link]) link the mol­ecules into infinite chains along the b-axis direction (Fig. 2[link]). The C—H⋯π inter­actions (Table 1[link]) may further stabilize the crystal structure.

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 and Cg4 are the centroids of rings A (C2–C7) and D (C9/C10/C15–C18), respectively.

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1O⋯N2 0.82 1.96 2.6667 (14) 144
N2—H2N⋯O1i 0.864 (15) 2.196 (15) 2.9870 (14) 152.2 (13)
C8—H8ACg1iv 0.96 2.82 3.6580 (17) 146
C13—H13⋯Cg4i 0.93 2.87 3.7336 (16) 155
C16—H16⋯Cg1v 0.93 2.87 3.4880 (15) 125
Symmetry codes: (i) [-x+{\script{3\over 2}}, y+{\script{1\over 2}}, z]; (iv) [x, -y-{\script{1\over 2}}, z-{\script{1\over 2}}]; (v) [x+{\script{1\over 2}}, -y-{\script{1\over 2}}, -z].
[Figure 2]
Figure 2
A partial packing diagram viewed along the a-axis direction with O—HPhnl⋯NPrmdn and N—HPrmdn⋯OPhnl (Phnl = phenol and Prmdn = perimidine) hydrogen bonds shown as dashed lines. H-atoms not included in hydrogen bonding have been omitted for clarity.

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 by 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. 3[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 (distinct 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 spot appearing near O1 indicates its role as the respective donor and/or acceptor; it also appears 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. 4[link]. The blue regions indicate the positive electrostatic potential (hydrogen-bond donors), while the red regions indicate the negative electrostatic potential (hydrogen-bond acceptors). The shape-index of the HS is a tool to visualize the 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. 5[link] clearly suggests that there are no ππ inter­actions in (I)[link].

[Figure 3]
Figure 3
View of the three-dimensional Hirshfeld surface of the title compound plotted over dnorm in the range −0.4133 to 1.3883 a.u.
[Figure 4]
Figure 4
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 5]
Figure 5
Hirshfeld surface of the title compound plotted over shape-index.

The overall two-dimensional fingerprint plot, Fig. 6[link]a, and those delineated into H⋯H, H⋯C/C⋯H, H⋯O/O⋯H, H⋯N/N⋯H, C⋯C and O⋯C/C⋯O contacts (McKinnon et al., 2007[McKinnon, J. J., Jayatilaka, D. & Spackman, M. A. (2007). Chem. Commun. pp. 3814-3816.]) are illustrated in Fig. 6[link] b-g, respectively, together with their relative contributions to the Hirshfeld surface. The most important inter­action is H⋯H contributing 49.0% to the overall crystal packing, which is reflected in Fig. 6[link]b as widely scattered points of high density due to the large hydrogen-atom content of the mol­ecule with the tip at de = di = 1.20 Å. In the presence of C—H⋯π inter­actions, the pair of characteristic wings in the fingerprint plot, Fig. 6[link]c, delineated into H⋯C/C⋯H contacts (Table 2[link]; 35.8% contribution to the HS) have the tips at de + di = 2.68 Å. The pair of spikes in the fingerprint plot delineated into H⋯O/O⋯H contacts (12.0% contribution, Fig. 6[link]d) have a symmetrical distribution of points with the tips at de + di = 3.03 Å. The H⋯N/N⋯H contacts (Fig. 6[link]e, 1.8% contribution) have a distribution of points with the tips at de + di = 2.72 Å. The C⋯C contacts (0.8%, Fig. 6[link]f) have the tip at de = di = 3.37 Å. Finally, the O⋯C/C⋯O inter­actions make only a 0.5% contribution to the overall crystal packing.

Table 2
Selected interatomic distances (Å)

O1⋯O2 2.5772 (14) C5⋯H8Ai 2.94
O1⋯N2 2.6668 (14) C5⋯H8B 2.72
C12⋯O1i 3.1736 (17) C5⋯H8C 2.80
C17⋯O1ii 3.3145 (17) C8⋯H5 2.55
C11⋯O1i 3.3650 (15) H13⋯C9i 2.93
N2⋯O1i 2.9867 (14) H13⋯C10i 2.97
H2N⋯O1i 2.196 (15) C10⋯H1 2.95
H18⋯O1ii 2.88 C12⋯H1Oi 2.88
H12⋯O1i 2.66 H1⋯H7 2.39
H17⋯O1ii 2.63 H1N⋯H18 2.44
O2⋯H6iii 2.87 H1O⋯H2N 2.31
N1⋯H1O 2.86 H17⋯H1Oii 2.57
H12⋯N1i 2.86 H18⋯H1Oii 2.47
N2⋯H1O 1.96 H2N⋯H12 2.43
C18⋯C12ii 3.567 (2) H5⋯H8B 2.28
C1⋯H1O 2.46 H5⋯H8C 2.40
C4⋯H8Ai 2.92 H14⋯H16 2.53
Symmetry codes: (i) [-x+{\script{3\over 2}}, y+{\script{1\over 2}}, z]; (ii) [x-{\script{1\over 2}}, y, -z+{\script{3\over 2}}]; (iii) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+1].
[Figure 6]
Figure 6
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) H⋯N/N⋯H and (f) O⋯C/C⋯O 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. 7[link]ac, respectively.

[Figure 7]
Figure 7
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 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.]), where a cluster of mol­ecules is generated by applying crystallographic symmetry operations with respect to a selected central mol­ecule within a 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 as −37.5 (Eele), −7.8 (Epol), −52.0 (Edis), 52.4 (Erep) and −58.4 (Etot) [or O1—H1O⋯N2 and −11.3 (Eele), −3.4 (Epol), −48.4 (Edis), 30.0 (Erep) and −38.0 (Etot) for N2—H2N⋯O1.

6. DFT calculations

The optimized structure of the title compound, (I)[link], in the gas phase was generated theoretically via density functional theory (DFT) using 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., Trucks, G. W., Schlegel, H. B., Scuseria, G. E., Robb, M. A., Cheeseman, J. R., et al. (2009). GAUSSIAN09. Gaussian Inc., Wallingford, CT, US]). The theoretical and experimental results were 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, electronegativity (χ), hardness (η), potential (μ), electrophilicity (ω) and softness (σ) are recorded in Table 4[link]. 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. 8[link]. The HOMO and LUMO are localized in the plane extending from the whole 2-(2,3-di­hydro-1H-perimidin-2-yl)-6-meth­oxy­phenol ring. The energy band gap [ΔE = ELUMO − EHOMO] of the mol­ecule is about 2.6162 eV, and the frontier mol­ecular orbital energies, EHOMO and ELUMO are −3.1985 and −0.5823 eV, respectively.

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

Bonds/angles X-ray B3LYP/6–311G(d,p)
O1—C3 1.3587 (14) 1.38948
O1—H1Oa 0.82 0.97611
N1—C9 1.3865 (16) 1.39921
N1—C1 1.4529 (17) 1.47118
N1—H1N 0.870 (15) 0.90721
C1—N2 1.4745 (16) 1.47531
C1—C2 1.5074 (17) 1.51309
O2—C4 1.3677 (15) 1.40231
O2—C8 1.4088 (17) 1.45201
N2—C11 1.4124 (16) 1.39016
N2—H2N 0.864 (15) 0.90717
     
C3—O1—H1Oa 109.5 109.04
C9—N1—C1 116.86 (10) 117.19
C9—N1—H1N 115.4 (10) 116.29
C1—N1—H1N 113.3 (10) 114.01
N1—C1—N2 106.56 (10) 106.87
N1—C1—C2 109.17 (10) 110.78
N2—C1—C2 111.38 (10) 110.82
N1—C1—H1a 109.9 110.12
N2—C1—H1a 109.9 109.09
Note: (a) These four entries were not refined, as they each include a constrained H atom.

Table 4
Calculated energies

Mol­ecular Energy (a.u.) (eV) Compound (I)
Total Energy TE (eV) −26013
EHOMO (eV) −3.1985
ELUMO (eV) −0.5823
Gap, ΔE (eV) 2.6162
Dipole moment, μ (Debye) 7.0880
Ionization potential, I (eV) 3.1985
Electron affinity, A 0.5823
Electronegativity, χ 1.8904
Hardness, η 1.3081
Electrophilicity index, ω 1.3660
Softness, σ 0.7645
Fraction of electrons transferred, ΔN 1.9530
[Figure 8]
Figure 8
The energy band gap of the title compound, (I)[link].

7. Database survey

Similar compounds of the perimidine derivative have also been reported (Ghorbani, 2012[Ghorbani, M. H. (2012). Acta Cryst. E68, o2605.]; Fun et al., 2011[Fun, H.-K., Chanawanno, K. & Chantrapromma, S. (2011). Acta Cryst. E67, o715-o716.]; Maloney et al., 2013[Maloney, S., Slawin, A. M. Z. & Woollins, J. D. (2013). Acta Cryst. E69, o246.]; Cucciolito et al., 2013b[Cucciolito, M. E., Panunzi, B., Ruffo, F. & Tuzi, A. (2013b). Acta Cryst. E69, o1133-o1134.]; Manimekalai et al., 2014[Manimekalai, A., Vijayalakshmi, N. & Selvanayagam, S. (2014). Acta Cryst. E70, o959.]), in which the groups at position 2 are almost coplanar with the perimidic nucleus (Ghorbani, 2012[Ghorbani, M. H. (2012). Acta Cryst. E68, o2605.]; Fun et al., 2011[Fun, H.-K., Chanawanno, K. & Chantrapromma, S. (2011). Acta Cryst. E67, o715-o716.]; Cucciolito et al., 2013b[Cucciolito, M. E., Panunzi, B., Ruffo, F. & Tuzi, A. (2013b). Acta Cryst. E69, o1133-o1134.]). The closest examples to the title compound, (I)[link], are (II) (Cucciolito et al., 2013b[Cucciolito, M. E., Panunzi, B., Ruffo, F. & Tuzi, A. (2013b). Acta Cryst. E69, o1133-o1134.]) and (III) (Fun et al., 2011[Fun, H.-K., Chanawanno, K. & Chantrapromma, S. (2011). Acta Cryst. E67, o715-o716.]), while (IV) (Ghorbani, 2012[Ghorbani, M. H. (2012). Acta Cryst. E68, o2605.]), (V) (Maloney et al., 2013[Maloney, S., Slawin, A. M. Z. & Woollins, J. D. (2013). Acta Cryst. E69, o246.]) and (VI) (Manimekalai et al., 2014[Manimekalai, A., Vijayalakshmi, N. & Selvanayagam, S. (2014). Acta Cryst. E70, o959.]) are more distant relatives.

[Scheme 2]

8. Synthesis and crystallization

The title compound, (I)[link], was synthesized from the condensation of ortho-vanillin (3 mmol) and 1,8- di­aminona­phthalene (4 mmol) in ether (30 ml) under agitation at room temperature. Brown single crystals were obtained by the slow evaporation of the acetone solvent after 15 days (yield: 75%).

9. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 5[link]. The C-bound H atoms were positioned geometrically, with C—H = 0.93 Å (for aromatic H atoms and H14C, H15A and H15B of the allyl moiety), 0.98 Å (for methine H atom) and 0.97 Å (for methyl­ene H atoms), and constrained to ride on their parent atoms, with Uiso(H) = 1.2Ueq(C). The hydroxyl H atom was placed in a calculated position with O—H = 0.82 Å and Uiso(H) = 1.5Ueq(O) while H atoms bonded to N atoms were refined independently with Uiso(H) = 1.2Ueq(N)

Table 5
Experimental details

Crystal data
Chemical formula C18H16N2O2
Mr 292.33
Crystal system, space group Orthorhombic, Pbca
Temperature (K) 293
a, b, c (Å) 12.7245 (7), 9.5887 (6), 23.7276 (14)
V3) 2895.0 (3)
Z 8
Radiation type Mo Kα
μ (mm−1) 0.09
Crystal size (mm) 0.52 × 0.10 × 0.04
 
Data collection
Diffractometer Rigaku XtaLAB PRO
Absorption correction Multi-scan (CrysAlis PRO; Rigaku OD, 2018[Rigaku OD (2018). CrysAlis PRO. Rigaku Oxford Diffraction, Yarnton, England.])
Tmin, Tmax 0.390, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections 16885, 3499, 2640
Rint 0.036
(sin θ/λ)max−1) 0.682
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.045, 0.118, 1.04
No. of reflections 3496
No. of parameters 207
H-atom treatment H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3) 0.20, −0.21
Computer programs: CrysAlis PRO (Rigaku OD, 2018[Rigaku OD (2018). CrysAlis PRO. Rigaku Oxford Diffraction, Yarnton, England.]), SHELXT (Sheldrick, 2015a[Sheldrick, G. M. (2015a). Acta Cryst. A71, 3-8.]) and SHELXL2018/3 (Sheldrick, 2015b[Sheldrick, G. M. (2015b). Acta Cryst. C71, 3-8.]).

Supporting information


Computing details top

Data collection: CrysAlis PRO (Rigaku OD, 2018); cell refinement: CrysAlis PRO (Rigaku OD, 2018); data reduction: CrysAlis PRO (Rigaku OD, 2018); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2018/3 (Sheldrick, 2015b).

2-(2,3-Dihydro-1H-perimidin-2-yl)-6-methoxyphenol top
Crystal data top
C18H16N2O2Dx = 1.341 Mg m3
Mr = 292.33Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, PbcaCell parameters from 6789 reflections
a = 12.7245 (7) Åθ = 3.2–28.1°
b = 9.5887 (6) ŵ = 0.09 mm1
c = 23.7276 (14) ÅT = 293 K
V = 2895.0 (3) Å3Elongated platelet, brown
Z = 80.52 × 0.10 × 0.04 mm
F(000) = 1232
Data collection top
Rigaku XtaLAB PRO
diffractometer
3499 independent reflections
Radiation source: micro-focus sealed X-ray tube, Rigaku micromax 0032640 reflections with I > 2σ(I)
Rigaku Integrated Confocal MaxFlux double bounce multi-layer mirror optics monochromatorRint = 0.036
Detector resolution: 5.811 pixels mm-1θmax = 29.0°, θmin = 2.4°
ω scansh = 1614
Absorption correction: multi-scan
(CrysAlisPro; Rigaku OD, 2018)
k = 1213
Tmin = 0.390, Tmax = 1.000l = 3030
16885 measured reflections
Refinement top
Refinement on F2Primary atom site location: other
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.045Hydrogen site location: mixed
wR(F2) = 0.118H atoms treated by a mixture of independent and constrained refinement
S = 1.04 w = 1/[σ2(Fo2) + (0.0609P)2 + 0.4131P]
where P = (Fo2 + 2Fc2)/3
3496 reflections(Δ/σ)max = 0.001
207 parametersΔρmax = 0.20 e Å3
0 restraintsΔρmin = 0.21 e Å3
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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O10.73352 (7)0.23966 (10)0.63178 (4)0.0437 (2)
H1O0.7314830.2940810.6584190.066*
N10.52935 (9)0.35194 (11)0.70590 (5)0.0395 (3)
H1N0.4730 (12)0.3089 (15)0.6946 (6)0.047*
C10.57436 (10)0.44289 (13)0.66329 (5)0.0373 (3)
H10.5322160.5280410.6599720.045*
O20.72915 (8)0.09678 (11)0.53981 (4)0.0519 (3)
N20.68133 (8)0.47793 (11)0.68254 (4)0.0379 (3)
H2N0.7113 (11)0.5331 (16)0.6587 (6)0.045*
C20.57650 (10)0.36729 (13)0.60760 (5)0.0363 (3)
C30.65312 (9)0.26779 (12)0.59586 (5)0.0346 (3)
C40.64940 (10)0.19120 (13)0.54596 (5)0.0383 (3)
C50.56894 (11)0.21405 (14)0.50790 (6)0.0449 (3)
H50.5661340.1632630.4745460.054*
C60.49246 (11)0.31282 (15)0.51959 (6)0.0500 (4)
H60.4382530.3279810.4940270.060*
C90.52580 (9)0.40296 (12)0.76054 (5)0.0346 (3)
C70.49623 (11)0.38823 (14)0.56858 (6)0.0458 (3)
H70.4445030.4543060.5758940.055*
C80.72720 (13)0.01056 (17)0.49174 (7)0.0603 (4)
H8A0.7880770.0485780.4916980.090*
H8B0.7273040.0673940.4584330.090*
H8C0.6648990.0458800.4923410.090*
C100.60767 (9)0.49588 (12)0.77664 (5)0.0335 (3)
C110.68804 (9)0.53139 (12)0.73789 (5)0.0347 (3)
C120.77148 (11)0.61181 (14)0.75512 (6)0.0441 (3)
H120.8259050.6318410.7302410.053*
C130.77415 (12)0.66349 (15)0.81036 (6)0.0506 (4)
H130.8304100.7188190.8215770.061*
C140.69668 (12)0.63475 (14)0.84781 (6)0.0479 (3)
H140.6992440.6731030.8837840.057*
C150.61190 (10)0.54681 (13)0.83261 (5)0.0384 (3)
C160.53296 (10)0.50546 (15)0.87065 (6)0.0451 (3)
H160.5328780.5408250.9071500.054*
C170.45685 (11)0.41435 (16)0.85456 (6)0.0498 (4)
H170.4066330.3860740.8806440.060*
C180.45257 (10)0.36232 (15)0.79961 (6)0.0445 (3)
H180.3998770.2999260.7895030.053*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0417 (5)0.0466 (5)0.0427 (5)0.0082 (4)0.0125 (4)0.0068 (4)
N10.0352 (6)0.0420 (6)0.0412 (6)0.0088 (5)0.0001 (4)0.0046 (5)
C10.0358 (7)0.0346 (6)0.0416 (7)0.0020 (5)0.0025 (5)0.0001 (5)
O20.0499 (6)0.0560 (6)0.0499 (6)0.0108 (5)0.0044 (4)0.0146 (5)
N20.0378 (6)0.0389 (6)0.0370 (6)0.0084 (5)0.0024 (4)0.0003 (4)
C20.0382 (6)0.0346 (6)0.0361 (6)0.0014 (5)0.0029 (5)0.0039 (5)
C30.0336 (6)0.0356 (6)0.0347 (6)0.0029 (5)0.0035 (5)0.0048 (5)
C40.0380 (7)0.0381 (6)0.0387 (7)0.0015 (5)0.0007 (5)0.0012 (5)
C50.0510 (8)0.0482 (8)0.0354 (7)0.0046 (6)0.0051 (6)0.0013 (6)
C60.0500 (8)0.0550 (8)0.0451 (8)0.0023 (7)0.0163 (6)0.0049 (7)
C90.0309 (6)0.0339 (6)0.0389 (7)0.0033 (5)0.0009 (5)0.0000 (5)
C70.0439 (7)0.0458 (7)0.0476 (8)0.0072 (6)0.0095 (6)0.0021 (6)
C80.0658 (10)0.0599 (10)0.0551 (9)0.0081 (8)0.0010 (7)0.0165 (8)
C100.0336 (6)0.0298 (6)0.0372 (6)0.0032 (5)0.0017 (5)0.0027 (5)
C110.0371 (6)0.0300 (6)0.0371 (6)0.0005 (5)0.0010 (5)0.0020 (5)
C120.0431 (7)0.0437 (7)0.0454 (7)0.0106 (6)0.0011 (6)0.0032 (6)
C130.0550 (9)0.0468 (8)0.0499 (8)0.0182 (7)0.0099 (6)0.0010 (7)
C140.0599 (9)0.0446 (7)0.0392 (7)0.0069 (7)0.0064 (6)0.0033 (6)
C150.0414 (7)0.0355 (6)0.0384 (7)0.0047 (5)0.0030 (5)0.0016 (5)
C160.0445 (7)0.0547 (8)0.0362 (7)0.0053 (6)0.0017 (5)0.0019 (6)
C170.0380 (7)0.0662 (9)0.0452 (8)0.0001 (7)0.0079 (6)0.0039 (7)
C180.0328 (7)0.0502 (8)0.0504 (8)0.0046 (6)0.0027 (6)0.0005 (6)
Geometric parameters (Å, º) top
O1—C31.3587 (14)C9—C101.4230 (17)
O1—H1O0.8200C7—H70.9300
N1—C91.3865 (16)C8—H8A0.9600
N1—C11.4529 (17)C8—H8B0.9600
N1—H1N0.870 (15)C8—H8C0.9600
C1—N21.4745 (16)C10—C151.4161 (17)
C1—C21.5074 (17)C10—C111.4168 (16)
C1—H10.9800C11—C121.3744 (18)
O2—C41.3677 (15)C12—C131.4017 (19)
O2—C81.4088 (17)C12—H120.9300
N2—C111.4124 (16)C13—C141.355 (2)
N2—H2N0.864 (15)C13—H130.9300
C2—C31.3922 (17)C14—C151.4160 (19)
C2—C71.3930 (17)C14—H140.9300
C3—C41.3942 (17)C15—C161.4074 (18)
C4—C51.3826 (18)C16—C171.359 (2)
C5—C61.386 (2)C16—H160.9300
C5—H50.9300C17—C181.397 (2)
C6—C71.370 (2)C17—H170.9300
C6—H60.9300C18—H180.9300
C9—C181.3710 (17)
O1···O22.5772 (14)C5···H8Ai2.94
O1···N22.6668 (14)C5···H8B2.72
C12···O1i3.1736 (17)C5···H8C2.80
C17···O1ii3.3145 (17)C8···H52.55
C11···O1i3.3650 (15)H13···C9i2.93
N2···O1i2.9867 (14)H13···C10i2.97
H2N···O1i2.196 (15)C10···H12.95
H18···O1ii2.88C12···H1Oi2.88
H12···O1i2.66H1···H72.39
H17···O1ii2.63H1N···H182.44
O2···H6iii2.87H1O···H2N2.31
N1···H1O2.86H17···H1Oii2.57
H12···N1i2.86H18···H1Oii2.47
N2···H1O1.96H2N···H122.43
C18···C12ii3.567 (2)H5···H8B2.28
C1···H1O2.46H5···H8C2.40
C4···H8Ai2.92H14···H162.53
C3—O1—H1O109.5C2—C7—H7119.5
C9—N1—C1116.86 (10)O2—C8—H8A109.5
C9—N1—H1N115.4 (10)O2—C8—H8B109.5
C1—N1—H1N113.3 (10)H8A—C8—H8B109.5
N1—C1—N2106.56 (10)O2—C8—H8C109.5
N1—C1—C2109.17 (10)H8A—C8—H8C109.5
N2—C1—C2111.38 (10)H8B—C8—H8C109.5
N1—C1—H1109.9C15—C10—C11119.89 (11)
N2—C1—H1109.9C15—C10—C9119.70 (11)
C2—C1—H1109.9C11—C10—C9120.31 (11)
C4—O2—C8117.50 (11)C12—C11—N2121.79 (11)
C11—N2—C1115.25 (10)C12—C11—C10119.96 (11)
C11—N2—H2N111.1 (10)N2—C11—C10118.20 (10)
C1—N2—H2N110.1 (10)C11—C12—C13119.68 (12)
C3—C2—C7118.64 (12)C11—C12—H12120.2
C3—C2—C1121.17 (11)C13—C12—H12120.2
C7—C2—C1120.00 (11)C14—C13—C12121.57 (13)
O1—C3—C2122.54 (11)C14—C13—H13119.2
O1—C3—C4116.99 (11)C12—C13—H13119.2
C2—C3—C4120.47 (11)C13—C14—C15120.54 (12)
O2—C4—C5125.78 (12)C13—C14—H14119.7
O2—C4—C3114.47 (11)C15—C14—H14119.7
C5—C4—C3119.75 (12)C16—C15—C14123.25 (12)
C4—C5—C6119.84 (12)C16—C15—C10118.50 (12)
C4—C5—H5120.1C14—C15—C10118.24 (12)
C6—C5—H5120.1C17—C16—C15120.63 (13)
C7—C6—C5120.39 (12)C17—C16—H16119.7
C7—C6—H6119.8C15—C16—H16119.7
C5—C6—H6119.8C16—C17—C18121.31 (13)
C18—C9—N1123.65 (12)C16—C17—H17119.3
C18—C9—C10119.61 (12)C18—C17—H17119.3
N1—C9—C10116.62 (11)C9—C18—C17120.20 (13)
C6—C7—C2120.90 (13)C9—C18—H18119.9
C6—C7—H7119.5C17—C18—H18119.9
C9—N1—C1—N256.76 (13)C18—C9—C10—C150.81 (17)
C9—N1—C1—C2177.15 (10)N1—C9—C10—C15176.97 (10)
N1—C1—N2—C1152.57 (13)C18—C9—C10—C11175.67 (11)
C2—C1—N2—C11171.54 (10)N1—C9—C10—C110.50 (16)
N1—C1—C2—C378.14 (14)C1—N2—C11—C12157.13 (12)
N2—C1—C2—C339.26 (16)C1—N2—C11—C1025.13 (15)
N1—C1—C2—C796.72 (13)C15—C10—C11—C121.88 (17)
N2—C1—C2—C7145.88 (12)C9—C10—C11—C12174.59 (11)
C7—C2—C3—O1179.32 (11)C15—C10—C11—N2179.66 (10)
C1—C2—C3—O14.39 (18)C9—C10—C11—N23.19 (17)
C7—C2—C3—C40.17 (18)N2—C11—C12—C13179.45 (12)
C1—C2—C3—C4175.10 (11)C10—C11—C12—C132.86 (19)
C8—O2—C4—C52.9 (2)C11—C12—C13—C140.8 (2)
C8—O2—C4—C3176.72 (12)C12—C13—C14—C152.2 (2)
O1—C3—C4—O20.28 (16)C13—C14—C15—C16175.57 (13)
C2—C3—C4—O2179.80 (11)C13—C14—C15—C103.1 (2)
O1—C3—C4—C5179.39 (12)C11—C10—C15—C16177.68 (11)
C2—C3—C4—C50.13 (18)C9—C10—C15—C161.19 (17)
O2—C4—C5—C6179.60 (12)C11—C10—C15—C141.09 (17)
C3—C4—C5—C60.0 (2)C9—C10—C15—C14177.58 (11)
C4—C5—C6—C70.2 (2)C14—C15—C16—C17176.13 (13)
C1—N1—C9—C18152.51 (12)C10—C15—C16—C172.57 (19)
C1—N1—C9—C1031.50 (15)C15—C16—C17—C182.0 (2)
C5—C6—C7—C20.1 (2)N1—C9—C18—C17177.36 (12)
C3—C2—C7—C60.1 (2)C10—C9—C18—C171.5 (2)
C1—C2—C7—C6175.04 (13)C16—C17—C18—C90.1 (2)
Symmetry codes: (i) x+3/2, y+1/2, z; (ii) x1/2, y, z+3/2; (iii) x+1/2, y+1/2, z+1.
Hydrogen-bond geometry (Å, º) top
Cg1 and Cg4 are the centroids of rings A (C2–C7) and D (C9/C10/C15–C18), respectively.
D—H···AD—HH···AD···AD—H···A
O1—H1O···N20.821.962.6667 (14)144
N2—H2N···O1i0.864 (15)2.196 (15)2.9870 (14)152.2 (13)
C8—H8A···Cg1iv0.962.823.6580 (17)146
C13—H13···Cg4i0.932.873.7336 (16)155
C16—H16···Cg1v0.932.873.4880 (15)125
Symmetry codes: (i) x+3/2, y+1/2, z; (iv) x, y1/2, z1/2; (v) x+1/2, y1/2, z.
Comparison of selected (X-ray and DFT) geometric data (Å, °) top
Bonds/anglesX-rayB3LYP/6-311G(d,p)
O1—C31.3587 (14)1.38948
O1—H1O0.820.97611
N1—C91.3865 (16)1.39921
N1—C11.4529 (17)1.47118
N1—H1N0.870 (15)0.90721
C1—N21.4745 (16)1.47531
C1—C21.5074 (17)1.51309
O2—C41.3677 (15)1.40231
O2—C81.4088 (17)1.45201
N2—C111.4124 (16)1.39016
N2—H2N0.864 (15)0.90717
C3—O1—H1O109.5109.04
C9—N1—C1116.86 (10)117.19
C9—N1—H1N115.4 (10)116.29
C1—N1—H1N113.3 (10)114.01
N1—C1—N2106.56 (10)106.87
N1—C1—C2109.17 (10)110.78
N2—C1—C2111.38 (10)110.82
N1—C1—H1109.9110.12
N2—C1—H1109.9109.09
Calculated energies top
Molecular Energy (a.u.) (eV)Compound (I)
Total Energy TE (eV)-26013
EHOMO (eV)-3.1985
ELUMO (eV)-0.5823
Gap, ΔE (eV)2.6162
Dipole moment, µ (Debye)7.0880
Ionisation potential, I (eV)3.1985
Electron affinity, A0.5823
Electronegativity, χ1.8904
Hardness, η1.3081
Electrophilicity index, ω1.3660
Softness, σ0.7645
Fraction of electrons transferred, ΔN1.9530
 

Funding information

TH is grateful to the Hacettepe University Scientific Research Project Unit (grant No. 013 D04 602 004).

References

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