Crystal structure of 2-ethyl­quinazoline-4(3H)-thione

Abstract

In the title compound, C₁₀H₁₀N₂S, all non-H atoms are almost coplanar [maximum deviation = 0.103 (1) Å]. In the crystal, N—H⋯S inter­actions form R ₂ ²(8) rings linking pairs of mol­ecules related by inversion. The mol­ecular pairs are stacked along [100]. A herringbone arrangement of pairs in the [010] direction forms layers parallel to (010).

Related literature  

For the synthesis of quinazoline-4(3H)-thio­nes, see: Bogert et al. (1903 ▶); Zoltewicz & Sharpless (1976 ▶); Segarra et al. (1998 ▶); El-Hiti (2004 ▶); Ozturk et al. (2007 ▶); El-Hiti et al. (2011 ▶).

Experimental  

Crystal data  

• C₁₀H₁₀N₂S

• M _r = 190.26

• Orthorhombic,

• a = 5.8231 (3) Å

• b = 14.3214 (6) Å

• c = 21.7365 (8) Å

• V = 1812.71 (14) ų

• Z = 8

• Mo Kα radiation

• μ = 0.31 mm⁻¹

• T = 150 K

• 0.41 × 0.24 × 0.15 mm

Data collection  

• Agilent SuperNova (Dual, Cu at zero, Atlas) diffractometer

• Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2014 ▶) T _min = 0.780, T _max = 1.000

• 7795 measured reflections

• 2240 independent reflections

• 1973 reflections with I > 2σ(I)

• R _int = 0.020

Refinement  

• R[F ² > 2σ(F ²)] = 0.033

• wR(F ²) = 0.087

• S = 1.03

• 2240 reflections

• 119 parameters

• H-atom parameters constrained

• Δρ_max = 0.30 e Å⁻³

• Δρ_min = −0.25 e Å⁻³

Data collection: CrysAlis PRO (Agilent, 2014 ▶); 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

CCDC reference: 1014729

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

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯S1i	0.88	2.53	3.3854 (11)	166

Symmetry code: (i) .

supplementary crystallographic information

S2. Structural commentary

The 2-ethyl-3H-quinazoline-4-thione molecule (Fig 1) is almost planer (apart from the ethyl hydrogens) with the ethyl group being twisted from the quinazoline-4-thione plane by 8.7 (2)°. N—H···S inter­actions form R₂²(8) rings to link pairs of molecules related by inversion. The pairs of molecules are stacked parallel to the a-axis (Fig 2). Adjacent pairs pack in a herring bone arrangement in the [010] direction to form layers parallel to the (010) plane. 2-(Substituted alkyl)-3H-quinazoline-4-thione derivatives can be obtained from double li­thia­tion of 2-alkyl-3H-quinazoline-4-thio­nes followed by reactions with electrophiles, including alkyl iodides, at low temperature in anhydrous THF (El-Hiti, 2004). Also, 3H-quinazoline-4-thio­nes are produced from the corresponding 3H-quinazoline-4-ones using phospho­rus penta­sulfide (Bogert et al., 1903; Ozturk et al., 2007; El-Hiti et al., 2011) or Lawesson's reagent (Segarra et al., 1998). 3H-Quinazoline-4-thio­nes have also been synthesized in one-step from reaction of 2-amino­benzo­nitriles and thio­amides in the presence of hydrogen bromide in various solvents on a steam bath for 1–4 h (Zoltewicz & Sharpless, 1976).

S5. Synthesis and crystallization

2-Ethyl-3H-quinazoline-4-thione was obtained in 92% yield from double li­thia­tion of 2-methyl-3H-quinazoline-4-thione with n-butyl­lithium at 78 ^οC in anhydrous THF under nitro­gen followed by reaction with iodo­methane (El-Hiti, 2004). Crystallization from methanol gave the title compound as yellow crystals. The NMR and low and high resolution mass spectra for the title compound were consistent with those reported (El-Hiti, 2004).

S6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 1. H atoms were placed in calculated positions with C—H = 0.95 and 0.98Å and refined in riding mode, U_iso(H) = 1.5U_eq(C) for methyl H atoms and 1.2Ueq(C) for aromatic H atoms

Figures

Fig. 1.

A molecule of the title compound showing atom labels and 50% probability displacement ellipsoids for non-H atoms.

Fig. 2.

Crystal structure packing showing N—H···S contacts as dotted lines.

Crystal data

C10H10N2S	Dx = 1.394 Mg m−3
Mr = 190.26	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pbca	Cell parameters from 3617 reflections
a = 5.8231 (3) Å	θ = 3.9–29.3°
b = 14.3214 (6) Å	µ = 0.31 mm−1
c = 21.7365 (8) Å	T = 150 K
V = 1812.71 (14) Å3	Plate, yellow
Z = 8	0.41 × 0.24 × 0.15 mm
F(000) = 800

Data collection

Agilent SuperNova (Dual, Cu at zero, Atlas) diffractometer	2240 independent reflections
Radiation source: SuperNova (Mo) X-ray Source	1973 reflections with I > 2σ(I)
Mirror monochromator	Rint = 0.020
ω scans	θmax = 29.8°, θmin = 3.0°
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2014)	h = −6→7
Tmin = 0.780, Tmax = 1.000	k = −19→14
7795 measured reflections	l = −23→29

Refinement

Refinement on F2	0 restraints
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.033	H-atom parameters constrained
wR(F2) = 0.087	w = 1/[σ2(Fo2) + (0.0416P)2 + 0.7981P] where P = (Fo2 + 2Fc2)/3
S = 1.03	(Δ/σ)max < 0.001
2240 reflections	Δρmax = 0.30 e Å−3
119 parameters	Δρmin = −0.25 e Å−3

Special details

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
C1	0.7433 (2)	0.57478 (9)	0.62537 (6)	0.0185 (3)
C2	0.6649 (2)	0.44643 (8)	0.55604 (5)	0.0178 (2)
C3	0.4705 (2)	0.42557 (8)	0.59550 (5)	0.0177 (3)
C4	0.4368 (2)	0.48131 (8)	0.64832 (5)	0.0183 (3)
C5	0.3171 (2)	0.35262 (9)	0.58239 (6)	0.0209 (3)
H5	0.3379	0.3158	0.5465	0.025*
C6	0.1366 (2)	0.33425 (9)	0.62146 (6)	0.0236 (3)
H6	0.0337	0.2845	0.6127	0.028*
C7	0.1046 (2)	0.38917 (9)	0.67440 (6)	0.0240 (3)
H7	−0.0197	0.3760	0.7013	0.029*
C8	0.2513 (2)	0.46175 (9)	0.68761 (6)	0.0218 (3)
H8	0.2272	0.4987	0.7233	0.026*
C9	0.8998 (2)	0.65696 (9)	0.63452 (6)	0.0227 (3)
H9A	0.8734	0.7023	0.6009	0.027*
H9B	1.0609	0.6354	0.6316	0.027*
C10	0.8668 (3)	0.70632 (9)	0.69567 (6)	0.0246 (3)
H10A	0.7058	0.7252	0.7000	0.037*
H10B	0.9652	0.7618	0.6972	0.037*
H10C	0.9080	0.6639	0.7293	0.037*
N1	0.78973 (18)	0.52156 (7)	0.57402 (5)	0.0188 (2)
H1	0.9086	0.5374	0.5513	0.023*
N2	0.57662 (19)	0.55697 (7)	0.66273 (5)	0.0199 (2)
S1	0.73978 (6)	0.38502 (2)	0.49367 (2)	0.02214 (11)

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
C1	0.0210 (6)	0.0177 (6)	0.0169 (6)	0.0022 (5)	−0.0006 (4)	−0.0010 (5)
C2	0.0203 (6)	0.0164 (5)	0.0166 (5)	0.0039 (5)	−0.0026 (5)	0.0008 (4)
C3	0.0194 (6)	0.0171 (6)	0.0167 (5)	0.0027 (5)	−0.0019 (5)	0.0020 (4)
C4	0.0197 (6)	0.0178 (6)	0.0172 (5)	0.0019 (5)	−0.0012 (4)	0.0010 (5)
C5	0.0237 (7)	0.0189 (6)	0.0202 (6)	0.0008 (5)	−0.0032 (5)	−0.0006 (5)
C6	0.0238 (7)	0.0212 (6)	0.0258 (6)	−0.0033 (5)	−0.0029 (5)	0.0012 (5)
C7	0.0213 (7)	0.0264 (7)	0.0244 (6)	−0.0013 (5)	0.0028 (5)	0.0038 (5)
C8	0.0242 (7)	0.0226 (6)	0.0186 (6)	0.0015 (5)	0.0016 (5)	0.0002 (5)
C9	0.0238 (7)	0.0208 (6)	0.0233 (6)	−0.0033 (5)	0.0041 (5)	−0.0040 (5)
C10	0.0292 (7)	0.0233 (6)	0.0214 (6)	−0.0047 (5)	0.0001 (5)	−0.0040 (5)
N1	0.0188 (5)	0.0194 (5)	0.0182 (5)	−0.0003 (4)	0.0030 (4)	−0.0024 (4)
N2	0.0220 (6)	0.0191 (5)	0.0187 (5)	−0.0006 (4)	0.0015 (4)	−0.0012 (4)
S1	0.0244 (2)	0.02191 (18)	0.02011 (17)	0.00029 (12)	0.00293 (12)	−0.00599 (12)

Geometric parameters (Å, º)

C1—N2	1.2908 (16)	C6—C7	1.4061 (19)
C1—N1	1.3784 (16)	C6—H6	0.9500
C1—C9	1.5017 (18)	C7—C8	1.3757 (19)
C2—N1	1.3560 (16)	C7—H7	0.9500
C2—C3	1.4514 (17)	C8—H8	0.9500
C2—S1	1.6737 (12)	C9—C10	1.5177 (17)
C3—C5	1.4038 (18)	C9—H9A	0.9900
C3—C4	1.4119 (16)	C9—H9B	0.9900
C4—N2	1.3910 (16)	C10—H10A	0.9800
C4—C8	1.4054 (18)	C10—H10B	0.9800
C5—C6	1.3766 (19)	C10—H10C	0.9800
C5—H5	0.9500	N1—H1	0.8800
N2—C1—N1	123.21 (12)	C6—C7—H7	119.6
N2—C1—C9	121.86 (11)	C7—C8—C4	120.08 (12)
N1—C1—C9	114.92 (11)	C7—C8—H8	120.0
N1—C2—C3	114.27 (11)	C4—C8—H8	120.0
N1—C2—S1	120.71 (10)	C1—C9—C10	113.84 (11)
C3—C2—S1	125.01 (10)	C1—C9—H9A	108.8
C5—C3—C4	119.83 (12)	C10—C9—H9A	108.8
C5—C3—C2	121.97 (11)	C1—C9—H9B	108.8
C4—C3—C2	118.19 (11)	C10—C9—H9B	108.8
N2—C4—C8	117.93 (11)	H9A—C9—H9B	107.7
N2—C4—C3	122.83 (11)	C9—C10—H10A	109.5
C8—C4—C3	119.22 (12)	C9—C10—H10B	109.5
C6—C5—C3	120.19 (12)	H10A—C10—H10B	109.5
C6—C5—H5	119.9	C9—C10—H10C	109.5
C3—C5—H5	119.9	H10A—C10—H10C	109.5
C5—C6—C7	119.94 (12)	H10B—C10—H10C	109.5
C5—C6—H6	120.0	C2—N1—C1	124.53 (11)
C7—C6—H6	120.0	C2—N1—H1	117.7
C8—C7—C6	120.73 (13)	C1—N1—H1	117.7
C8—C7—H7	119.6	C1—N2—C4	116.89 (11)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···S1i	0.88	2.53	3.3854 (11)	166

Symmetry code: (i) −x+2, −y+1, −z+1.