Crystal structure of 4-methyl­sulfanyl-2-phenyl­quinazoline

Mohammed B Alshammari; Keith Smith; Amany S Hegazy; Benson M Kariuki; Gamal A El-Hiti

doi:10.1107/S1600536814015657

. 2014 Jul 23;70(Pt 8):o919–o920. doi: 10.1107/S1600536814015657

Crystal structure of 4-methylsulfanyl-2-phenylquinazoline

Mohammed B Alshammari ^a, Keith Smith ^b, Amany S Hegazy ^b, Benson M Kariuki ^b,^‡, Gamal A El-Hiti ^c,^*

PMCID: PMC4158504 PMID: 25249928

Abstract

In the title compound, C₁₅H₁₂N₂S, the methylthioquinazoline group is planar with the methyl C displaced by only 0.116 (3) Å from the plane of the quinazoline moiety. The dihedral angle between the phenyl ring and the quinazoline ring system is 13.95 (5)°. In the crystal, each molecule is linked by π–π stacking between to two adjacent inversion-related molecules. On one side, the inverted quinazoline groups interact with a centroid–centroid distance of 3.7105 (9) Å. On the other side, the quinazoline group interacts with the pyrimidine and phenyl rings of the second neighbour with centroid–centroid distances of 3.5287 (8) and 3.8601 (9) Å, respectively.

Keywords: crystal structure, methylthioquinazoline, π–π stacking

Related literature

For the synthesis of 4-alkythioqinazolines, see: Leonard & Curtin (1946 ▶); Hearn et al. (1951 ▶); Meerwein et al. (1956 ▶); Blatter & Lukaszewski (1964 ▶); Segarra et al. (1998 ▶); Smith et al. (2005a ▶,b ▶).

Experimental

Crystal data

C₁₅H₁₂N₂S
M _r = 252.33
Monoclinic,
a = 10.1951 (3) Å
b = 7.3545 (2) Å
c = 16.5300 (5) Å
β = 102.860 (3)°
V = 1208.33 (6) Å³
Z = 4
Mo Kα radiation
μ = 0.25 mm⁻¹
T = 150 K
0.23 × 0.18 × 0.15 mm

Data collection

Agilent SuperNova (Dual, Cu at zero, Atlas) diffractometer
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2013 ▶) T _min = 0.848, T _max = 1.000
11140 measured reflections
3025 independent reflections
2558 reflections with I > 2σ(I)
R _int = 0.030

Refinement

R[F ² > 2σ(F ²)] = 0.039
wR(F ²) = 0.097
S = 1.08
3025 reflections
164 parameters
H-atom parameters constrained
Δρ_max = 0.29 e Å⁻³
Δρ_min = −0.34 e Å⁻³

Data collection: CrysAlis PRO (Agilent, 2013 ▶); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supplementary Material

Crystal structure: contains datablock(s) I, New_Global_Publ_Block. DOI: 10.1107/S1600536814015657/xu5801sup1.cif

e-70-0o919-sup1.cif^{(397.5KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536814015657/xu5801Isup2.hkl

e-70-0o919-Isup2.hkl^{(166.2KB, hkl)}

Click here for additional data file.^{(4.8KB, cml)}

Supporting information file. DOI: 10.1107/S1600536814015657/xu5801Isup3.cml

CCDC reference: 1012164

Additional supporting information: crystallographic information; 3D view; checkCIF report

Acknowledgments

This project was supported by the Deanship of Scientific Research at Salman bin Abdulaziz University under research project 2013/01/8.

supplementary crystallographic information

S1. Chemical context

S2. Structural commentary

In the 4-(methylthio)-2-phenylquinazoline molecule (Fig 1), the angle between the planes through the phenyl and phenylquinazoline ring systems is 13.95 (5)°. The molecules are stacked in the [010] direction with approximately parallel molecular planes. With no strong H-bond donors, one N atom accepts a long C—H···N contact linking molecules along [101]. The second N atom is not involved. 4-Methylthioquinazoline derivatives can be obtained from reaction of the potassium salt of 3H-quinazoline-4-thiones with iodomethane (Leonard & Curtin, 1946; Meerwein et al., 1956). Quinazoline-4-thiones are produced from the corresponding 3H-quinazoline-4-ones using phosphorus pentasulfide (Hearn, et al., 1951), Lawesson's reagent (Segarra et al., 1998) or isothiocyanates (Blatter & Lukaszewski, 1964). In a continuation of our research focused on new synthetic routes towards novel substituted 4-alkylthioquinazoline derivatives (Smith et al., 2005a,b) we have synthesized 4-(methylthio)-2-phenylquinazoline in a high yield (Smith et al., 2005a).

S3. Supramolecular features

S4. Database survey

S5. Synthesis and crystallization

To a solution of 2-phenyl-3H-quinazoline-4-thione (4.81 g, 20.2 mmol) in a 1:1 mixture of MeOH and water (50 ml) containing KOH (3.0 g), was added iodomethane (3.41 g, 24.0 mmol). The reaction mixture was stirred for 20 min at room temperature and the solid obtained was filtered, washed with H₂O (3 × 30 ml), dried and recrystallized from Et₂O to give 4-(methylthio)-2-phenylquinazoline (4.63 g, 18.3 mmol, 91%) as colourless crystals, m.p. 93-94 °C [lit. 94 °C (H₂O); Meerwein et al., 1956). ¹H NMR (400 MHz, CDCl₃, δ, p.p.m.) 8.70-8.66 (m, 2 H, ArH), 8.10-8.03 (m, 2 H, ArH), 7.83 (app. dt, J = 1, 8 Hz, 1 H, H-7), 7.58-7.51 (m, 4 H, ArH), 2.85 (s, 3 H, CH₃). ¹³C NMR (100 MHz, CDCl₃, d, p.p.m.) 171.8 (s, C-2), 159.2 (s, C-4), 149.1 (s, C-8a), 138.5 (s, C-1 of Ph), 133.9 (d, C-7), 131.0 (d, C-4 of Ph), 129.4 (d, C-8), 129.0 (d, C-3/C-5 of Ph), 128.9 (d, C-2/C-6 of Ph), 127.1 (d, C-6), 124.1 (d, C-5), 123.0 (s, C-4a), 13.0 (q, CH₃). EI—MS (m/z, %): 252 (M⁺, 100), 251 (72), 205 (60), 102 (47), 77 (61), 51 (33). CI—MS (m/z, %): 253 (MH⁺, 100), 207 (3). HRMS (CI): Calculated for C₁₅H₁₃N₂S [MH] 253.0794; found, 253.0789.

S6. Refinement

H atoms were placed in calculated positions with C—H = 0.95 and 0.98 Å and refined in riding mode, U_iso(H) = 1.5U_eq(C) for methyl H atoms and 1.2U_eq(C) for aromatic H atoms.