2,3-Di­hydro­pyrrolo­[2,1-b]quinazoline-9(1H)-thione

In the crystal, mol­ecules of the title compound, C₁₁H₁₀N₂S, are connected by C—H⋯N inter­actions around threefold axes. Furthermore, they form stacks along the c axis showing π–π inter­actions between pyrimidine rings [centroid–centroid distance = 3.721 (1) Å]. The central ring is essentially planar with an r.m.s. deviation of 0.007 Å. The five-membered ring adopts an envelope conformation with the flap atom deviating by 0.241 (4) Å from the mean plane (r.m.s. deviation = 0.002 Å) through the other four ring atoms.

Related literature

For the synthesis of 2,3-dihydro-1H,9H-pyrrolo­[2,1-b]quinazolin-9-one and the title compound, see: Abduraza­kov et al. (2007); Shakhidoyatov & Kadyrov (1977); Elmuradov et al. (2010). For related structures, see Elmuradov et al. (2010); Turgunov et al. (1995).

Experimental

Crystal data

• C₁₁H₁₀N₂S

• M_r = 202.27

• Trigonal, R 3c

• a = 26.206 (1) Å

• c = 7.441 (2) Å

• V = 4425.5 (12) ų

• Z = 18

• Cu Kα radiation

• μ = 2.57 mm⁻¹

• T = 295 K

• 0.65 × 0.25 × 0.20 mm

Data collection

• Oxford Diffraction Xcalibur Ruby diffractometer

• Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009) T_min = 0.601, T_max = 1.000

• 5753 measured reflections

• 1379 independent reflections

• 1305 reflections with I > 2σ(I)

• R_int = 0.021

Refinement

• R[F² > 2σ(F²)] = 0.029

• wR(F²) = 0.078

• S = 1.06

• 1379 reflections

• 128 parameters

• 1 restraint

• H-atom parameters constrained

• Δρ_max = 0.16 e Å⁻³

• Δρ_min = −0.19 e Å⁻³

• Absolute structure: Flack (1983), 501 Friedel pairs

• Flack parameter: −0.003 (19)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C7—H7A⋯N1^i	0.93	2.61	3.464 (4)	153
Symmetry code: (i) -y+1, x-y, z.

Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP (Bruker, 1998); software used to prepare material for publication: publCIF (Westrip, 2010).

Supporting information

S1. Comment

The title compound was synthesized by the reaction of 2,3-dihydro-1H,9H-pyrrolo[2,1-b]quinazolin-9-one with phosphorus pentasulfide (Figure 1). X-ray single-crystal diffraction study reveals that the title compound crystallizes in the space group R3c with one molecule in the asymmetric unit. The molecule is almost planar (excluding the atom C10) with r.m.s. deviation of 0.014 Å. The central (pyrimidinic) ring is planar with rms deviations of 0.007Å. Conformation of five-membered (pyrrolic) ring is envelope with deviation of the atom C10 (0.241 (4) Å) from mean plane of other four atoms (rms deviations of 0.002 Å) of the ring. In the structure weak C—H···N interactions (Table 1) are observed. The molecules are stacked along the c axis by π–π stacking interactions between pyrimidine rings [centroid-centroid distances = 3.721 (1) Å].

Related literature

For the synthesis of 2,3-dihydro-1H,9H-pyrrolo[2,1-b]quinazolin-9-one and the title compound, see: Abdurazakov et al. (2007); Shakhidoyatov & Kadyrov (1977); Elmuradov et al. (2010). For related structures, see Elmuradov et al. (2010); Turgunov et al. (1995).

S2. Experimental

2.5 g (13 mmole) of 2,3-dihydro-1H,9H-pyrrolo[2,1]quinazolin-9-one was dissolved in 15 ml m-xylene and 2.98 g (13 mmole) of phosphorus pentasulfide were added (Figure 1). Reaction mixture was boiled 2 h and allowed to cool up to room temperature. The precipitate was filtered, flushed with m-xylene (3 ml) and 10% NaOH (50 ml) was added, then the precipittate was filtered and washed with water to get neutral medium and was dried. After recrystallization from hexane 1.96 g (72%) the title compound crystals. Suitable for X-ray diffraction crystals was obtained from hexane with m.p. 138 °C

¹H NMR (400 MHz, CDCl₃): 8.67 (1H, dd, J=8.3, J=1.7, H-8), 7.69 (1H, td, J=8.3, J=1.7, H-6), 7.59 (1H, dd, J=8.3, J=1.2, H-5), 7.43 (1H, td, J=8.3, J=1.2, H-6), 4.47 (2H, t, J=7.5, 1-CH₂), 3.25 (2H, t, J=7.9, 3-CH₂), 2.28 (2H, m, 2-CH₂)

S3. Refinement

H atoms were positioned geometrically and treated as riding on their C atoms, with C—H distances of 0.93 Å (aromatic)and 0.97 Å (CH₂) and were refined with U_iso(H)=1.2Ueq(C).

Computing details

Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell refinement: CrysAlis PRO (Oxford Diffraction, 2009); data reduction: CrysAlis PRO (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP (Bruker, 1998); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures

	Fig. 1. Reaction scheme
	Fig. 2. The molecular structure of the title compound with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.

2,3-Dihydropyrrolo[2,1-b]quinazoline-9(1H)-thione

Crystal data

C11H10N2S	Dx = 1.366 Mg m^−3
Mr = 202.27	Melting point: 411 K
Trigonal, R3c	Cu Kα radiation, λ = 1.54184 Å
Hall symbol: R 3 -2"c	Cell parameters from 2338 reflections
a = 26.206 (1) Å	θ = 3.4–66.8°
c = 7.441 (2) Å	µ = 2.57 mm^−1
V = 4425.5 (12) Å^3	T = 295 K
Z = 18	Prism, yellow
F(000) = 1908	0.65 × 0.25 × 0.20 mm

Data collection

Oxford Diffraction Xcalibur Ruby diffractometer	1379 independent reflections
Radiation source: Enhance (Cu) X-ray Source	1305 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.021
Detector resolution: 10.2576 pixels mm^-1	θmax = 66.8°, θmin = 3.4°
ω scans	h = −28→31
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)	k = −31→31
Tmin = 0.601, Tmax = 1.000	l = −8→8
5753 measured reflections

Refinement

Refinement on F^2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F^2 > 2σ(F^2)] = 0.029	w = 1/[σ^2(Fo^2) + (0.0613P)^2 + 0.028P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.078	(Δ/σ)max < 0.001
S = 1.06	Δρmax = 0.16 e Å^−3
1379 reflections	Δρmin = −0.19 e Å^−3
128 parameters	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
1 restraint	Extinction coefficient: 0.00144 (11)
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack (1983), 501 Friedel pairs
Secondary atom site location: difference Fourier map	Absolute structure parameter: −0.003 (19)

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.

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 > σ(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 (Ų)

	x	y	z	Uiso*/Ueq
S1	0.89225 (2)	0.23959 (3)	0.13284 (10)	0.0588 (2)
N1	0.71400 (8)	0.21624 (8)	0.2807 (3)	0.0562 (5)
C2	0.72288 (9)	0.17396 (9)	0.2343 (3)	0.0480 (4)
N3	0.77699 (7)	0.18140 (7)	0.1857 (2)	0.0445 (4)
C4	0.82758 (8)	0.23443 (9)	0.1852 (3)	0.0451 (4)
C4A	0.81976 (9)	0.28375 (9)	0.2345 (3)	0.0477 (4)
C5	0.86723 (10)	0.34181 (10)	0.2392 (4)	0.0614 (5)
H5A	0.9050	0.3495	0.2105	0.074*
C6	0.85814 (13)	0.38726 (11)	0.2857 (5)	0.0765 (8)
H6A	0.8898	0.4256	0.2880	0.092*
C7	0.80209 (14)	0.37644 (12)	0.3296 (5)	0.0827 (9)
H7A	0.7964	0.4076	0.3604	0.099*
C8	0.75527 (11)	0.32025 (12)	0.3276 (5)	0.0746 (7)
H8A	0.7180	0.3135	0.3581	0.090*
C8A	0.76270 (10)	0.27240 (9)	0.2803 (3)	0.0528 (5)
C9	0.67738 (10)	0.11011 (10)	0.2275 (4)	0.0601 (5)
H9A	0.6436	0.1040	0.1570	0.072*
H9B	0.6642	0.0947	0.3475	0.072*
C10	0.70825 (10)	0.08040 (10)	0.1391 (4)	0.0670 (6)
H10A	0.6999	0.0450	0.2044	0.080*
H10B	0.6949	0.0697	0.0161	0.080*
C11	0.77385 (10)	0.12481 (9)	0.1437 (4)	0.0548 (5)
H11A	0.7934	0.1146	0.2356	0.066*
H11B	0.7920	0.1267	0.0283	0.066*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.0415 (3)	0.0673 (4)	0.0720 (3)	0.0306 (2)	0.0040 (2)	−0.0012 (3)
N1	0.0407 (8)	0.0548 (10)	0.0767 (12)	0.0265 (8)	−0.0002 (8)	0.0031 (9)
C2	0.0375 (9)	0.0509 (10)	0.0541 (10)	0.0210 (8)	−0.0041 (8)	0.0011 (9)
N3	0.0422 (8)	0.0457 (9)	0.0480 (8)	0.0238 (7)	−0.0023 (6)	0.0014 (7)
C4	0.0420 (9)	0.0512 (11)	0.0442 (9)	0.0250 (9)	−0.0033 (8)	0.0018 (8)
C4A	0.0444 (10)	0.0472 (10)	0.0541 (10)	0.0249 (8)	−0.0033 (8)	0.0033 (9)
C5	0.0499 (11)	0.0504 (11)	0.0791 (14)	0.0215 (9)	−0.0041 (11)	0.0013 (11)
C6	0.0686 (15)	0.0437 (12)	0.110 (2)	0.0229 (12)	−0.0094 (14)	−0.0012 (13)
C7	0.0838 (17)	0.0545 (13)	0.124 (3)	0.0454 (13)	−0.0099 (18)	−0.0084 (15)
C8	0.0615 (14)	0.0649 (14)	0.112 (2)	0.0429 (12)	−0.0006 (15)	−0.0018 (15)
C8A	0.0485 (11)	0.0482 (11)	0.0667 (12)	0.0279 (9)	−0.0062 (10)	0.0009 (9)
C9	0.0429 (10)	0.0519 (11)	0.0752 (13)	0.0160 (9)	−0.0014 (10)	−0.0002 (11)
C10	0.0616 (14)	0.0464 (11)	0.0850 (16)	0.0211 (10)	−0.0043 (13)	−0.0053 (11)
C11	0.0601 (12)	0.0512 (11)	0.0592 (11)	0.0325 (10)	−0.0004 (11)	−0.0029 (12)

Geometric parameters (Å, º)

S1—C4	1.6771 (18)	C6—H6A	0.9300
N1—C2	1.288 (3)	C7—C8	1.366 (4)
N1—C8A	1.384 (3)	C7—H7A	0.9300
C2—N3	1.380 (3)	C8—C8A	1.406 (3)
C2—C9	1.493 (3)	C8—H8A	0.9300
N3—C4	1.359 (3)	C9—C10	1.524 (3)
N3—C11	1.477 (3)	C9—H9A	0.9700
C4—C4A	1.453 (3)	C9—H9B	0.9700
C4A—C5	1.404 (3)	C10—C11	1.520 (3)
C4A—C8A	1.413 (3)	C10—H10A	0.9700
C5—C6	1.371 (4)	C10—H10B	0.9700
C5—H5A	0.9300	C11—H11A	0.9700
C6—C7	1.388 (4)	C11—H11B	0.9700
C2—N1—C8A	116.55 (17)	C7—C8—H8A	119.6
N1—C2—N3	124.32 (18)	C8A—C8—H8A	119.6
N1—C2—C9	125.92 (19)	N1—C8A—C8	118.8 (2)
N3—C2—C9	109.75 (18)	N1—C8A—C4A	122.71 (18)
C4—N3—C2	123.61 (16)	C8—C8A—C4A	118.5 (2)
C4—N3—C11	124.21 (16)	C2—C9—C10	104.87 (19)
C2—N3—C11	112.11 (16)	C2—C9—H9A	110.8
N3—C4—C4A	114.17 (16)	C10—C9—H9A	110.8
N3—C4—S1	120.86 (15)	C2—C9—H9B	110.8
C4A—C4—S1	124.97 (16)	C10—C9—H9B	110.8
C5—C4A—C8A	119.56 (19)	H9A—C9—H9B	108.8
C5—C4A—C4	121.83 (19)	C11—C10—C9	106.58 (18)
C8A—C4A—C4	118.61 (18)	C11—C10—H10A	110.4
C6—C5—C4A	120.2 (2)	C9—C10—H10A	110.4
C6—C5—H5A	119.9	C11—C10—H10B	110.4
C4A—C5—H5A	119.9	C9—C10—H10B	110.4
C5—C6—C7	120.5 (2)	H10A—C10—H10B	108.6
C5—C6—H6A	119.7	N3—C11—C10	104.32 (18)
C7—C6—H6A	119.7	N3—C11—H11A	110.9
C8—C7—C6	120.4 (2)	C10—C11—H11A	110.9
C8—C7—H7A	119.8	N3—C11—H11B	110.9
C6—C7—H7A	119.8	C10—C11—H11B	110.9
C7—C8—C8A	120.9 (2)	H11A—C11—H11B	108.9

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C7—H7A···N1^i	0.93	2.61	3.464 (4)	153

Symmetry code: (i) −y+1, x−y, z.