organic compounds
H)-one
of 3-amino-2-ethylquinazolin-4(3aCornea Research Chair, Department of Optometry, College of Applied Medical Sciences, King Saud University, PO Box 10219, Riyadh 11433, Saudi Arabia, bSchool of Chemistry, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, Wales, and cDepartment of Chemistry, Faculty of Science and Humanities, Shaqra University, Al-Duwadmi, Saudi Arabia
*Correspondence e-mail: gelhiti@ksu.edu.sa
The molecule of the title compound, C10H11N3O, is planar, including the ethyl group, as indicated by the N—C—C—C torsion angle of 1.5 (2)°. In the crystal, inversion-related molecules are stacked along the a axis. Molecules are oriented head-to-tail and display π–π interactions with a centroid-to-centroid distance of 3.6664 (8) Å. N—H⋯O hydrogen bonds between molecules generate a `step' structure through formation of an R22(10) ring.
CCDC reference: 1416070
1. Related literature
For related compounds, see: Ma et al. (2013); Adib et al. (2012); Xu et al. (2012); Sasmal et al. (2012); Kumar et al. (2011); Rohini et al. (2010); Davies et al. (2010). For quinazolin-4(3H)-one ring-system modification through lithiation, see: Smith et al. (2004, 1996, 1995). For the crystal structures of related compounds, see: El-Hiti et al. (2014); Yang et al. (2009); Coogan et al. (1999).
2. Experimental
2.1. Crystal data
|
2.3. Refinement
|
|
Data collection: CrysAlis PRO (Agilent, 2014); cell CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS2013 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012) and CHEMDRAW Ultra (Cambridge Soft, 2001).
Supporting information
CCDC reference: 1416070
https://doi.org/10.1107/S2056989015014450/hg5454sup1.cif
contains datablocks I, New_Global_Publ_Block. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989015014450/hg5454Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2056989015014450/hg5454Isup3.cml
Quinazolines have various interesting biological applications (Sasmal et al., 2012; Rohini et al., 2010). Quinazolin-4(3H)-ones synthesis involves use of various synthetic procedures. The most common starting materials are 2-aminobenzonitrile (Ma et al., 2013), 2-bromobenzamides (Xu et al., 2012), isatoic anhydride (Adib et al., 2012), anthranilic acid (Kumar et al., 2011), methyl 2-aminobenzoate (Davies et al., 2010). Lithiation of 2-n-alkyl- and 2-unsubstituted 3-acylaminoquinazolin-4(3H)-ones with a lithium reagent in tetrahydrofuran at a low temperature followed by reactions of various electrophiles with the lithium reagents produced in-situ gave the corresponding 2-substituted derivatives in good to excellent yields (Smith et al., 2004, 1996, 1995). For the X-ray structures for related compounds, see: El-Hiti et al. (2014); Yang et al. (2009); Coogan et al. (1999).
A mixture of methyl 2-aminobenzoate and propionic anhydride (1.4 mole equivalents) was heated for 30 minutes at 105 °C. The mixture was cooled to 75 °C and diluted with ethanol (50 mL). Hydrazine monohydrate (10 mole equivalents) was added in a dropwise manner over 10 minutes and the mixture was refluxed for 1 h. The mixture was cooled to room temperature and the solvent was removed under reduced pressure. The residue obtained was purified by
(silica gel hexane/diethyl ether in 4:1 by volume) to give 3-amino-2-ethylquinazolin-4(3H)-one in 82% yield (Davies et al., 2010). Crystallization from a mixture of ethyl acetate and diethyl ether (1:2 by volume) gave colourless crystals of the title compound. The spectroscopic data for the title compound were identical with those reported (Davies et al., 2010).H atoms were positioned geometrically and refined using a riding model with Uiso(H) constrained to be 1.2 times Ueq for the atom it is bonded to except for methyl groups where it was 1.5 times with
about the C—C bond. The amide hydrogen atoms were located in the difference Fourier map and refined freely.The π - π interaction with a centroid to centroid distance of 3.66 (2)Å. N—H···O hydrogen bonds between molecules (x,y,z) and (-x,-y+1, -z+1) generate a 'step' structure through formation of a R22(10) ring.
comprises a molecule of C10H11N3O (Fig. 1). The molecule is planar, including the ethyl group as indicated by the N2—C1—C9—C10 torsion angle of 1.5 (2)°. Inversion related molecules are stacked along the a axis (Fig. 2). Molecules (x,y,z) and (1-x, -y,1-z) are oriented head-to-tail and displayQuinazolines have various interesting biological applications (Sasmal et al., 2012; Rohini et al., 2010). Quinazolin-4(3H)-ones synthesis involves use of various synthetic procedures. The most common starting materials are 2-aminobenzonitrile (Ma et al., 2013), 2-bromobenzamides (Xu et al., 2012), isatoic anhydride (Adib et al., 2012), anthranilic acid (Kumar et al., 2011), methyl 2-aminobenzoate (Davies et al., 2010). Lithiation of 2-n-alkyl- and 2-unsubstituted 3-acylaminoquinazolin-4(3H)-ones with a lithium reagent in tetrahydrofuran at a low temperature followed by reactions of various electrophiles with the lithium reagents produced in-situ gave the corresponding 2-substituted derivatives in good to excellent yields (Smith et al., 2004, 1996, 1995). For the X-ray structures for related compounds, see: El-Hiti et al. (2014); Yang et al. (2009); Coogan et al. (1999).
The π - π interaction with a centroid to centroid distance of 3.66 (2)Å. N—H···O hydrogen bonds between molecules (x,y,z) and (-x,-y+1, -z+1) generate a 'step' structure through formation of a R22(10) ring.
comprises a molecule of C10H11N3O (Fig. 1). The molecule is planar, including the ethyl group as indicated by the N2—C1—C9—C10 torsion angle of 1.5 (2)°. Inversion related molecules are stacked along the a axis (Fig. 2). Molecules (x,y,z) and (1-x, -y,1-z) are oriented head-to-tail and displayFor related compounds, see: Ma et al. (2013); Adib et al. (2012); Xu et al. (2012); Sasmal et al. (2012); Kumar et al. (2011); Rohini et al. (2010); Davies et al. (2010). For quinazolin-4(3H)-one ring-system modification through lithiation, see: Smith et al. (2004, 1996, 1995). For the crystal structures of related compounds, see: El-Hiti et al. (2014); Yang et al. (2009); Coogan et al. (1999).
A mixture of methyl 2-aminobenzoate and propionic anhydride (1.4 mole equivalents) was heated for 30 minutes at 105 °C. The mixture was cooled to 75 °C and diluted with ethanol (50 mL). Hydrazine monohydrate (10 mole equivalents) was added in a dropwise manner over 10 minutes and the mixture was refluxed for 1 h. The mixture was cooled to room temperature and the solvent was removed under reduced pressure. The residue obtained was purified by
(silica gel hexane/diethyl ether in 4:1 by volume) to give 3-amino-2-ethylquinazolin-4(3H)-one in 82% yield (Davies et al., 2010). Crystallization from a mixture of ethyl acetate and diethyl ether (1:2 by volume) gave colourless crystals of the title compound. The spectroscopic data for the title compound were identical with those reported (Davies et al., 2010). detailsH atoms were positioned geometrically and refined using a riding model with Uiso(H) constrained to be 1.2 times Ueq for the atom it is bonded to except for methyl groups where it was 1.5 times with
about the C—C bond. The amide hydrogen atoms were located in the difference Fourier map and refined freely.Data collection: CrysAlis PRO (Agilent, 2014); cell
CrysAlis PRO (Agilent, 2014); data reduction: CrysAlis PRO (Agilent, 2014); program(s) used to solve structure: SHELXS2013 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012) and CHEMDRAW Ultra (Cambridge Soft, 2001).C10H11N3O | F(000) = 200 |
Mr = 189.22 | Dx = 1.328 Mg m−3 |
Triclinic, P1 | Melting point: 398 K |
a = 7.0230 (5) Å | Cu Kα radiation, λ = 1.54184 Å |
b = 7.6198 (7) Å | Cell parameters from 1907 reflections |
c = 9.7868 (6) Å | θ = 6.5–73.7° |
α = 69.709 (7)° | µ = 0.73 mm−1 |
β = 89.242 (5)° | T = 293 K |
γ = 75.191 (7)° | Block, colourless |
V = 473.27 (7) Å3 | 0.38 × 0.20 × 0.08 mm |
Z = 2 |
Agilent SuperNova Dual Source diffractometer with an Atlas detector | 1657 reflections with I > 2σ(I) |
ω scans | Rint = 0.015 |
Absorption correction: gaussian (CrysAlis PRO; Agilent, 2014) | θmax = 73.9°, θmin = 6.5° |
Tmin = 0.741, Tmax = 0.924 | h = −8→8 |
3303 measured reflections | k = −9→8 |
1858 independent reflections | l = −10→12 |
Refinement on F2 | 0 restraints |
Least-squares matrix: full | Hydrogen site location: mixed |
R[F2 > 2σ(F2)] = 0.061 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.196 | w = 1/[σ2(Fo2) + (0.1458P)2 + 0.021P] where P = (Fo2 + 2Fc2)/3 |
S = 1.07 | (Δ/σ)max < 0.001 |
1858 reflections | Δρmax = 0.35 e Å−3 |
136 parameters | Δρmin = −0.22 e Å−3 |
C10H11N3O | γ = 75.191 (7)° |
Mr = 189.22 | V = 473.27 (7) Å3 |
Triclinic, P1 | Z = 2 |
a = 7.0230 (5) Å | Cu Kα radiation |
b = 7.6198 (7) Å | µ = 0.73 mm−1 |
c = 9.7868 (6) Å | T = 293 K |
α = 69.709 (7)° | 0.38 × 0.20 × 0.08 mm |
β = 89.242 (5)° |
Agilent SuperNova Dual Source diffractometer with an Atlas detector | 1858 independent reflections |
Absorption correction: gaussian (CrysAlis PRO; Agilent, 2014) | 1657 reflections with I > 2σ(I) |
Tmin = 0.741, Tmax = 0.924 | Rint = 0.015 |
3303 measured reflections |
R[F2 > 2σ(F2)] = 0.061 | 0 restraints |
wR(F2) = 0.196 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.07 | Δρmax = 0.35 e Å−3 |
1858 reflections | Δρmin = −0.22 e Å−3 |
136 parameters |
Experimental. Absorption correction: CrysAlisPro, Agilent Technologies, Version 1.171.37.33 (release 27-03-2014 CrysAlis171 .NET) (compiled Mar 27 2014,17:12:48) Numerical absorption correction based on gaussian integration over a multifaceted crystal model Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm. |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
x | y | z | Uiso*/Ueq | ||
C1 | 0.26318 (18) | −0.0469 (2) | 0.59059 (14) | 0.0441 (4) | |
C2 | 0.18669 (19) | 0.2641 (2) | 0.38779 (16) | 0.0485 (4) | |
C3 | 0.21085 (18) | 0.1504 (2) | 0.29325 (14) | 0.0455 (4) | |
C4 | 0.25874 (19) | −0.0513 (2) | 0.35723 (14) | 0.0453 (4) | |
C5 | 0.1873 (2) | 0.2421 (3) | 0.14073 (16) | 0.0585 (4) | |
H5 | 0.1547 | 0.3768 | 0.0991 | 0.070* | |
C6 | 0.2123 (3) | 0.1324 (3) | 0.05335 (16) | 0.0711 (5) | |
H6 | 0.1976 | 0.1923 | −0.0478 | 0.085* | |
C7 | 0.2597 (3) | −0.0691 (3) | 0.11692 (19) | 0.0738 (5) | |
H7 | 0.2761 | −0.1428 | 0.0571 | 0.089* | |
C8 | 0.2829 (3) | −0.1613 (2) | 0.26567 (18) | 0.0616 (5) | |
H8 | 0.3144 | −0.2961 | 0.3059 | 0.074* | |
C9 | 0.2868 (2) | −0.1443 (2) | 0.75358 (14) | 0.0541 (4) | |
H9A | 0.1644 | −0.0989 | 0.7931 | 0.065* | |
H9B | 0.3894 | −0.1063 | 0.7928 | 0.065* | |
C10 | 0.3393 (3) | −0.3628 (3) | 0.80379 (17) | 0.0703 (5) | |
H10A | 0.2385 | −0.4018 | 0.7655 | 0.105* | |
H10B | 0.3492 | −0.4162 | 0.9087 | 0.105* | |
H10C | 0.4636 | −0.4096 | 0.7691 | 0.105* | |
N1 | 0.21763 (16) | 0.15389 (17) | 0.53566 (13) | 0.0475 (4) | |
N2 | 0.28333 (17) | −0.14907 (17) | 0.50721 (12) | 0.0479 (4) | |
N3 | 0.2043 (3) | 0.2510 (2) | 0.63756 (16) | 0.0683 (5) | |
O1 | 0.14455 (19) | 0.44171 (16) | 0.34527 (14) | 0.0704 (4) | |
H3A | 0.080 (3) | 0.329 (3) | 0.630 (2) | 0.079 (6)* | |
H3B | 0.292 (4) | 0.328 (5) | 0.609 (3) | 0.111 (9)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0404 (6) | 0.0519 (7) | 0.0392 (7) | −0.0129 (5) | 0.0037 (5) | −0.0148 (5) |
C2 | 0.0494 (7) | 0.0445 (7) | 0.0510 (8) | −0.0144 (5) | 0.0072 (5) | −0.0151 (6) |
C3 | 0.0457 (7) | 0.0494 (8) | 0.0400 (7) | −0.0154 (5) | 0.0048 (5) | −0.0122 (6) |
C4 | 0.0494 (7) | 0.0498 (7) | 0.0403 (7) | −0.0174 (5) | 0.0067 (5) | −0.0173 (6) |
C5 | 0.0588 (8) | 0.0659 (9) | 0.0424 (8) | −0.0201 (7) | 0.0043 (6) | −0.0066 (6) |
C6 | 0.0789 (11) | 0.0986 (14) | 0.0375 (7) | −0.0316 (10) | 0.0073 (7) | −0.0206 (8) |
C7 | 0.0926 (12) | 0.0963 (13) | 0.0520 (9) | −0.0368 (10) | 0.0153 (8) | −0.0421 (9) |
C8 | 0.0781 (10) | 0.0627 (9) | 0.0559 (9) | −0.0253 (8) | 0.0121 (7) | −0.0312 (7) |
C9 | 0.0482 (7) | 0.0729 (9) | 0.0367 (7) | −0.0158 (6) | 0.0031 (5) | −0.0142 (6) |
C10 | 0.0729 (10) | 0.0711 (10) | 0.0464 (8) | −0.0147 (8) | −0.0002 (7) | 0.0010 (7) |
N1 | 0.0511 (6) | 0.0505 (7) | 0.0451 (7) | −0.0128 (5) | 0.0045 (4) | −0.0227 (5) |
N2 | 0.0556 (7) | 0.0458 (6) | 0.0408 (7) | −0.0147 (5) | 0.0055 (5) | −0.0129 (5) |
N3 | 0.0801 (10) | 0.0733 (9) | 0.0628 (9) | −0.0136 (8) | 0.0049 (7) | −0.0428 (7) |
O1 | 0.0890 (8) | 0.0436 (6) | 0.0744 (8) | −0.0149 (5) | 0.0118 (6) | −0.0182 (5) |
C1—N2 | 1.2937 (19) | C6—H6 | 0.9300 |
C1—N1 | 1.3840 (19) | C7—C8 | 1.370 (2) |
C1—C9 | 1.4986 (18) | C7—H7 | 0.9300 |
C2—O1 | 1.2245 (18) | C8—H8 | 0.9300 |
C2—N1 | 1.3853 (19) | C9—C10 | 1.508 (2) |
C2—C3 | 1.453 (2) | C9—H9A | 0.9700 |
C3—C4 | 1.394 (2) | C9—H9B | 0.9700 |
C3—C5 | 1.4027 (19) | C10—H10A | 0.9600 |
C4—N2 | 1.3862 (18) | C10—H10B | 0.9600 |
C4—C8 | 1.406 (2) | C10—H10C | 0.9600 |
C5—C6 | 1.370 (3) | N1—N3 | 1.4227 (16) |
C5—H5 | 0.9300 | N3—H3A | 0.91 (2) |
C6—C7 | 1.392 (3) | N3—H3B | 0.93 (3) |
N2—C1—N1 | 122.58 (12) | C7—C8—H8 | 120.1 |
N2—C1—C9 | 120.35 (13) | C4—C8—H8 | 120.1 |
N1—C1—C9 | 117.07 (12) | C1—C9—C10 | 113.52 (13) |
O1—C2—N1 | 120.90 (14) | C1—C9—H9A | 108.9 |
O1—C2—C3 | 124.96 (14) | C10—C9—H9A | 108.9 |
N1—C2—C3 | 114.14 (12) | C1—C9—H9B | 108.9 |
C4—C3—C5 | 120.75 (14) | C10—C9—H9B | 108.9 |
C4—C3—C2 | 118.64 (13) | H9A—C9—H9B | 107.7 |
C5—C3—C2 | 120.61 (14) | C9—C10—H10A | 109.5 |
N2—C4—C3 | 123.07 (12) | C9—C10—H10B | 109.5 |
N2—C4—C8 | 118.33 (13) | H10A—C10—H10B | 109.5 |
C3—C4—C8 | 118.60 (14) | C9—C10—H10C | 109.5 |
C6—C5—C3 | 119.79 (16) | H10A—C10—H10C | 109.5 |
C6—C5—H5 | 120.1 | H10B—C10—H10C | 109.5 |
C3—C5—H5 | 120.1 | C1—N1—C2 | 123.65 (12) |
C5—C6—C7 | 119.60 (14) | C1—N1—N3 | 117.72 (12) |
C5—C6—H6 | 120.2 | C2—N1—N3 | 118.63 (13) |
C7—C6—H6 | 120.2 | C1—N2—C4 | 117.90 (12) |
C8—C7—C6 | 121.48 (16) | N1—N3—H3A | 110.0 (14) |
C8—C7—H7 | 119.3 | N1—N3—H3B | 104.8 (18) |
C6—C7—H7 | 119.3 | H3A—N3—H3B | 109 (2) |
C7—C8—C4 | 119.78 (16) | ||
O1—C2—C3—C4 | −179.89 (12) | N2—C1—C9—C10 | 1.5 (2) |
N1—C2—C3—C4 | 0.7 (2) | N1—C1—C9—C10 | −179.13 (11) |
O1—C2—C3—C5 | 0.4 (2) | N2—C1—N1—C2 | 0.9 (2) |
N1—C2—C3—C5 | −178.98 (10) | C9—C1—N1—C2 | −178.40 (10) |
C5—C3—C4—N2 | −179.87 (11) | N2—C1—N1—N3 | −178.35 (11) |
C2—C3—C4—N2 | 0.4 (2) | C9—C1—N1—N3 | 2.30 (19) |
C5—C3—C4—C8 | 0.0 (2) | O1—C2—N1—C1 | 179.18 (12) |
C2—C3—C4—C8 | −179.75 (11) | C3—C2—N1—C1 | −1.4 (2) |
C4—C3—C5—C6 | −0.3 (2) | O1—C2—N1—N3 | −1.5 (2) |
C2—C3—C5—C6 | 179.44 (12) | C3—C2—N1—N3 | 177.87 (11) |
C3—C5—C6—C7 | 0.4 (3) | N1—C1—N2—C4 | 0.3 (2) |
C5—C6—C7—C8 | −0.2 (3) | C9—C1—N2—C4 | 179.64 (10) |
C6—C7—C8—C4 | −0.1 (3) | C3—C4—N2—C1 | −1.0 (2) |
N2—C4—C8—C7 | −179.95 (14) | C8—C4—N2—C1 | 179.19 (11) |
C3—C4—C8—C7 | 0.2 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3A···O1i | 0.91 (2) | 2.12 (2) | 2.974 (2) | 157.1 (19) |
Symmetry code: (i) −x, −y+1, −z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3A···O1i | 0.91 (2) | 2.12 (2) | 2.974 (2) | 157.1 (19) |
Symmetry code: (i) −x, −y+1, −z+1. |
Footnotes
‡Additional correspondence author, email: kariukib@cardiff.ac.uk.
Acknowledgements
The authors extend their appreciation to the British Council, Riyadh, Saudi Arabia, for funding this research and to Cardiff University for continued support.
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