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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 4| April 2011| Pages o923-o924
doi:10.1107/S1600536811009664

2-Methyl-4-phenyl-3,4-di­hydro­quinazoline

Arto Valkonen,a* Erkki Kolehmainen,a Anna Zakrzewska,b Agnieszka Skotnickab and Ryszard Gawineckib

aUniversity of Jyväskylä, Department of Chemistry, PO Box 35, FIN-40014 Jyväskylä, Finland, and bUniversity of Technology and Life Sciences, Department of Chemistry, Seminaryjna 3, PL-85-326 Bydgoszcz, Poland
*Correspondence e-mail: arto.m.valkonen@jyu.fi

(Received 9 March 2011; accepted 14 March 2011; online 19 March 2011)

The title compound, C15H14N2, was formed during the lithia­tion of 2-methyl­quinazoline with phenyl­lithium followed by hydrolysis of the inter­mediate lithium 2-methyl-4-phenyl-4H-quinazolin-3-ide. NMR spectra as well as single-crystal X-ray structural data indicate that the reaction product to have the same structure in chloro­form solution as in the crystalline state. The phenyl substituent is twisted out of the plane of the 3,4-dihydro­quinazoline ring system by 86.47 (7)°. In the crystal, inter­molecular N—H⋯N inter­actions connect the mol­ecules into infinite chains.

Related literature

For organolithium compounds and lithia­tion, see: Gawinecki et al. (2006[Gawinecki, R., Kolehmainen, E., Loghmani-Khouzani, H., Ośmiałowski, B., Lovász, T. & Rosa, P. (2006). Eur. J. Org. Chem. pp. 2817-2824.]); Kolehmainen et al. (2000[Kolehmainen, E., Ośmiałowski, B., Krygowski, T. M., Kauppinen, R., Nissinen, M. & Gawinecki, R. (2000). J. Chem. Soc. Perkin Trans. 2, pp. 1259-1266.]); Wakefield (1976[Wakefield, B. J. (1976). The Chemistry of Organolithium Compounds, pp. 26, 32, 112, 138, 190. Oxford: Pergamon Press.]); Armarego (1967[Armarego, W. L. F. (1967). The Chemistry of Heterocyclic Compounds, Fused Pyrimidines, Part I, Quinazolines, edited by D. J. Brown, p. 35. New York: Interscience.]). For previous characterizations of the title compound, see: Suri et al. (1993[Suri, K. A., Satti, N. K., Mahajan, B., Suri, O. P. & Dhar, K. L. (1993). Indian J. Chem. Sect. B, 32, 1171-1172.]). For related structures, see: Rajnikant et al. (2002[Rajnikant, Gupta, V. K., Suri, O. P. & Lal, M. (2002). Indian J. Pure Appl. Phys. 40, 59-61.]).

[Scheme 1]

Experimental

Crystal data

  • C15H14N2

  • Mr = 222.28

  • Trigonal, P 31

  • a = 9.5600 (4) Å

  • c = 11.2569 (5) Å

  • V = 890.97 (7) Å3

  • Z = 3

  • Mo Kα radiation

  • μ = 0.07 mm−1

  • T = 123 K

  • 0.35 × 0.13 × 0.12 mm
Data collection

  • Bruker–Nonius KappaCCD with APEXII detector diffractometer

  • 6729 measured reflections

  • 1468 independent reflections

  • 1215 reflections with I > 2σ(I)

  • Rint = 0.068
Refinement

  • R[F2 > 2σ(F2)] = 0.046

  • wR(F2) = 0.095

  • S = 1.06

  • 1468 reflections

  • 155 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.19 e Å−3

  • Δρmin = −0.19 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
N3—H3⋯N1i 0.88 2.04 2.908 (3) 169
Symmetry code: (i) [-y, x-y+1, z+{\script{1\over 3}}].

Data collection: COLLECT (Bruker, 2008[Bruker (2008). COLLECT. Bruker AXS Inc., Madison, Wisconsin, USA..]); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter & R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: DENZO-SMN; program(s) used to solve structure: SIR2004 (Burla et al., 2005[Burla, M. C., Caliandro, R., Camalli, M., Carrozzini, B., Cascarano, G. L., De Caro, L., Giacovazzo, C., Polidori, G. & Spagna, R. (2005). J. Appl. Cryst. 38, 381-388.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and Mercury (Macrae, et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811009664/im2274sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811009664/im2274Isup2.hkl

checkCIF report


Comment top

Addition of phenyllithium to 2-methylquinazoline takes place exclusively at the 3,4-position (neither 2-methyl-2-phenyl-1,2-dihydroquinazoline nor 2-methyl-4-phenyl-1,4-dihydroquinazoline were detected in the reaction mixture). Susceptibility of quinazolines to undergo the nucleophilic addition to their 3,4-double bonds has been reported earlier (Suri et al., 1993). It is also known that 4-substituted 3,4-dihydroquinazolines can be generated from quinazolines when treated with organometallic compounds (Armarego, 1967). Furthermore, low susceptibility of 2-methyl group to lithiation precludes 2-methylquinazoline to be used as a starting material in syntheses of the important Cexo-substituted 2-methylquinazolines (Wakefield, 1976; Kolehmainen et al., 2000; Gawinecki et al., 2006).

In crystalline state the title compound shows the 3,4-dihydroquinazoline moiety to be planar (Fig. 1). The phenyl substituent is twisted out of plane of the moiety by 86.47 (7) °, which is rather close to the twist (79.3 (1) °) found in 2-methyl-4-phenyl-3,4-dihydroquinazolinium chloride (Rajnikant et al., 2002). Intermolecular N3—H···N1 hydrogen bonds (-y, x-y + 1, z + 1/3 direction) define the supramolecular structure and connect the molecules to infinite helical chains (Fig. 2). Unfortunately, no reliable determination of the absolute structure (or handedness of helix) is possible by X-ray crystallography.

Related literature top

For organolithium compounds and lithiation, see: Gawinecki et al. (2006); Kolehmainen et al. (2000); Wakefield (1976); Armarego (1967). For previous characterizations of the title compound, see: Suri et al. (1993). For related structures, see: Rajnikant et al. (2002).

Experimental top

A solution of 2-methyl-quinazoline (10.09 g, 0.07 mol) in absolute ethyl ether (100 ml) was added dropwise with stirring to a solution of phenyllithium [obtained by a standard method starting from freshly distilled bromobenzene (15.70 g, 0.1 mol), absolute ethyl ether (0.5 L) and lithium (2.80 g, 0.4 mol)]. The reaction mixture was stirred at room temperature for additional 2 h and the reaction was quenched by addition of water (0.5 L). The organic layer was combined with the ether extracts of the water layer, dried (K2CO3) and evaporated to dryness. The crude solid product was recrystallized from ethanol to give white crystals (51%) melting at 168–170 °C [lit. mp 168–170 °C (Suri et al., 1993)]. 1H NMR (CDCl3): δ (p.p.m.) = 7.26–7.34 (m, 5H, H12—H16), 7.13 (dd, 1H, H7), 7.02 (d, 1H, H8), 6.90 (dd, 1H, H6), 6.71 (d, 1H, H5), 5.67 (s, 1H, H4), 2.02 (s, 3H, CH3). 13C NMR (CDCl3): δ (p.p.m.) = 153.9 (C2), 145.3 (C11), 140.6 (C9), 128.1 (C7), 127.8 (C14), 128.7 (C13, C15), 127.3 (C12, C16), 126.7 (C5), 124.1 (C6), 123.3 (C10), 58.1 (C4), 22.5 (C17).

Suitable single crystals for X-ray diffraction were obtained by very slow evaporation of analytical sample from NMR-tube, where CDCl3 was used as a solvent.

Refinement top

In the absence of significant anomalous disperson effects, Friedel pairs were averaged. All H atoms were visible in electron density maps, but were calculated at their idealized positions and allowed to ride on their parent atoms at C—H distances of 0.95 Å (aromatic), 0.98 Å (methyl), 1.00 Å (methine), and N—H distance of 0.88 Å, with Uiso(H) of 1.2 times Ueq(C,N) or 1.5 times Ueq(C) (methyl).

Computing details top

Data collection: COLLECT (Bruker, 2008); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997); data reduction: DENZO-SMN (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR2004 (Burla et al., 2005); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and Mercury (Macrae, et al., 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound showing the atom-labeling scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are represented by circles of arbitrary size.
[Figure 2] Fig. 2. Part of the helical chain. Right-handed arbitrary presentation.
2-Methyl-4-phenyl-3,4-dihydroquinazoline top
Crystal data top
C15H14N2Dx = 1.243 Mg m−3
Mr = 222.28Mo Kα radiation, λ = 0.71073 Å
Trigonal, P31Cell parameters from 3635 reflections
Hall symbol: P 31θ = 0.4–28.3°
a = 9.5600 (4) ŵ = 0.07 mm−1
c = 11.2569 (5) ÅT = 123 K
V = 890.97 (7) Å3Long plate, colourless
Z = 30.35 × 0.13 × 0.12 mm
F(000) = 354
Data collection top
Bruker–Nonius KappaCCD with APEXII detector
diffractometer		1215 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.068
Graphite monochromatorθmax = 28.2°, θmin = 2.5°
Detector resolution: 9 pixels mm-1h = −12→12
ϕ and ω scansk = −12→12
6729 measured reflectionsl = −12→14
1468 independent reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.046Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.095H-atom parameters constrained
S = 1.06 w = 1/[σ2(Fo2) + (0.0321P)2 + 0.2356P]
where P = (Fo2 + 2Fc2)/3
1468 reflections(Δ/σ)max < 0.001
155 parametersΔρmax = 0.19 e Å−3
1 restraintΔρmin = −0.19 e Å−3
Crystal data top
C15H14N2Z = 3
Mr = 222.28Mo Kα radiation
Trigonal, P31µ = 0.07 mm−1
a = 9.5600 (4) ÅT = 123 K
c = 11.2569 (5) Å0.35 × 0.13 × 0.12 mm
V = 890.97 (7) Å3
Data collection top
Bruker–Nonius KappaCCD with APEXII detector
diffractometer		1215 reflections with I > 2σ(I)
6729 measured reflectionsRint = 0.068
1468 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0461 restraint
wR(F2) = 0.095H-atom parameters constrained
S = 1.06Δρmax = 0.19 e Å−3
1468 reflectionsΔρmin = −0.19 e Å−3
155 parameters
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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 (Å2) top
xyzUiso*/Ueq
N1−0.1844 (3)0.2606 (3)0.0291 (2)0.0332 (5)
N3−0.1137 (3)0.4459 (3)0.1862 (2)0.0308 (5)
H3−0.15200.47420.24700.037*
C2−0.2197 (3)0.3278 (3)0.1150 (2)0.0277 (6)
C40.0619 (3)0.5311 (3)0.1691 (2)0.0266 (6)
H40.11250.52330.24470.032*
C50.2646 (3)0.4997 (4)0.0469 (3)0.0339 (7)
H50.34740.58630.09100.041*
C60.3061 (4)0.4266 (4)−0.0421 (3)0.0379 (7)
H60.41650.4634−0.05910.045*
C70.1854 (4)0.2994 (4)−0.1060 (3)0.0362 (7)
H70.21290.2484−0.16670.043*
C80.0256 (4)0.2473 (3)−0.0813 (2)0.0327 (6)
H8−0.05630.1604−0.12580.039*
C9−0.0184 (3)0.3198 (3)0.0081 (2)0.0281 (6)
C100.1033 (3)0.4480 (3)0.0727 (2)0.0264 (6)
C110.1197 (3)0.7087 (3)0.1459 (2)0.0257 (6)
C120.1080 (3)0.7642 (3)0.0349 (2)0.0295 (6)
H120.07220.6927−0.03110.035*
C130.1485 (3)0.9247 (3)0.0197 (3)0.0341 (7)
H130.14250.9627−0.05700.041*
C140.1977 (3)1.0291 (4)0.1157 (3)0.0351 (7)
H140.22191.13760.10550.042*
C150.2112 (3)0.9745 (3)0.2266 (3)0.0337 (6)
H150.24701.04610.29250.040*
C160.1724 (3)0.8150 (3)0.2415 (2)0.0287 (6)
H160.18200.77810.31780.034*
C17−0.3942 (3)0.2713 (4)0.1398 (3)0.0384 (7)
H17A−0.46230.17670.09070.058*
H17B−0.41700.35810.12110.058*
H17C−0.41720.24240.22390.058*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0291 (12)0.0346 (13)0.0338 (13)0.0144 (11)−0.0030 (10)−0.0035 (11)
N30.0272 (12)0.0290 (12)0.0297 (12)0.0090 (10)0.0067 (10)−0.0042 (10)
C20.0270 (14)0.0274 (14)0.0282 (14)0.0131 (12)0.0016 (11)0.0043 (11)
C40.0253 (13)0.0249 (13)0.0282 (14)0.0114 (11)−0.0007 (11)0.0003 (11)
C50.0275 (14)0.0318 (15)0.0395 (17)0.0126 (12)0.0032 (12)−0.0008 (12)
C60.0352 (16)0.0366 (16)0.0451 (18)0.0204 (14)0.0136 (14)0.0069 (14)
C70.0548 (19)0.0348 (16)0.0307 (15)0.0313 (15)0.0137 (14)0.0080 (13)
C80.0410 (16)0.0273 (14)0.0308 (15)0.0179 (13)0.0017 (13)−0.0010 (12)
C90.0329 (15)0.0278 (13)0.0264 (13)0.0174 (12)−0.0015 (12)0.0014 (11)
C100.0276 (13)0.0230 (13)0.0279 (14)0.0122 (11)0.0036 (11)0.0032 (11)
C110.0196 (12)0.0264 (13)0.0309 (15)0.0113 (11)0.0030 (10)0.0009 (11)
C120.0266 (14)0.0333 (15)0.0297 (14)0.0158 (12)−0.0011 (12)−0.0010 (12)
C130.0306 (15)0.0352 (16)0.0378 (16)0.0175 (13)0.0008 (12)0.0069 (13)
C140.0277 (15)0.0271 (14)0.0511 (18)0.0141 (12)0.0046 (13)0.0047 (13)
C150.0278 (15)0.0312 (15)0.0416 (16)0.0142 (12)−0.0011 (12)−0.0073 (13)
C160.0253 (13)0.0306 (14)0.0298 (15)0.0137 (12)−0.0021 (11)−0.0030 (11)
C170.0282 (16)0.0404 (17)0.0404 (17)0.0125 (13)−0.0001 (13)−0.0014 (13)
Geometric parameters (Å, º) top
N1—C21.296 (4)C8—H80.9500
N1—C91.413 (3)C9—C101.401 (4)
N3—C21.341 (4)C11—C121.384 (4)
N3—C41.467 (3)C11—C161.390 (4)
N3—H30.8800C12—C131.392 (4)
C2—C171.500 (4)C12—H120.9500
C4—C101.509 (4)C13—C141.384 (4)
C4—C111.523 (3)C13—H130.9500
C4—H41.0000C14—C151.384 (4)
C5—C61.388 (4)C14—H140.9500
C5—C101.394 (4)C15—C161.387 (4)
C5—H50.9500C15—H150.9500
C6—C71.387 (5)C16—H160.9500
C6—H60.9500C17—H17A0.9800
C7—C81.378 (4)C17—H17B0.9800
C7—H70.9500C17—H17C0.9800
C8—C91.400 (4)
C2—N1—C9116.5 (2)C5—C10—C9119.3 (2)
C2—N3—C4124.2 (2)C5—C10—C4119.9 (2)
C2—N3—H3117.9C9—C10—C4120.8 (2)
C4—N3—H3117.9C12—C11—C16119.2 (2)
N1—C2—N3126.1 (2)C12—C11—C4121.9 (2)
N1—C2—C17118.6 (2)C16—C11—C4118.6 (2)
N3—C2—C17115.3 (2)C11—C12—C13120.2 (3)
N3—C4—C10109.3 (2)C11—C12—H12119.9
N3—C4—C11108.5 (2)C13—C12—H12119.9
C10—C4—C11114.8 (2)C14—C13—C12120.4 (3)
N3—C4—H4108.0C14—C13—H13119.8
C10—C4—H4108.0C12—C13—H13119.8
C11—C4—H4108.0C15—C14—C13119.6 (3)
C6—C5—C10121.1 (3)C15—C14—H14120.2
C6—C5—H5119.5C13—C14—H14120.2
C10—C5—H5119.5C14—C15—C16120.0 (3)
C7—C6—C5119.6 (3)C14—C15—H15120.0
C7—C6—H6120.2C16—C15—H15120.0
C5—C6—H6120.2C15—C16—C11120.6 (3)
C8—C7—C6119.9 (3)C15—C16—H16119.7
C8—C7—H7120.0C11—C16—H16119.7
C6—C7—H7120.0C2—C17—H17A109.5
C7—C8—C9121.3 (3)C2—C17—H17B109.5
C7—C8—H8119.4H17A—C17—H17B109.5
C9—C8—H8119.4C2—C17—H17C109.5
C8—C9—C10118.9 (2)H17A—C17—H17C109.5
C8—C9—N1118.5 (3)H17B—C17—H17C109.5
C10—C9—N1122.6 (2)
C9—N1—C2—N3−1.0 (4)N1—C9—C10—C4−0.4 (4)
C9—N1—C2—C17179.0 (3)N3—C4—C10—C5−175.0 (2)
C4—N3—C2—N17.2 (4)C11—C4—C10—C562.8 (3)
C4—N3—C2—C17−172.8 (3)N3—C4—C10—C95.4 (3)
C2—N3—C4—C10−8.7 (4)C11—C4—C10—C9−116.8 (3)
C2—N3—C4—C11117.2 (3)N3—C4—C11—C12−81.0 (3)
C10—C5—C6—C7−0.4 (4)C10—C4—C11—C1241.6 (3)
C5—C6—C7—C80.4 (4)N3—C4—C11—C1693.3 (3)
C6—C7—C8—C9−0.3 (4)C10—C4—C11—C16−144.1 (2)
C7—C8—C9—C100.2 (4)C16—C11—C12—C13−0.1 (4)
C7—C8—C9—N1−179.9 (2)C4—C11—C12—C13174.2 (2)
C2—N1—C9—C8177.9 (3)C11—C12—C13—C14−1.3 (4)
C2—N1—C9—C10−2.3 (4)C12—C13—C14—C152.0 (4)
C6—C5—C10—C90.3 (4)C13—C14—C15—C16−1.3 (4)
C6—C5—C10—C4−179.3 (3)C14—C15—C16—C11−0.1 (4)
C8—C9—C10—C5−0.2 (4)C12—C11—C16—C150.8 (4)
N1—C9—C10—C5179.9 (2)C4—C11—C16—C15−173.7 (2)
C8—C9—C10—C4179.4 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3···N1i0.882.042.908 (3)169
Symmetry code: (i) −y, x−y+1, z+1/3.

Experimental details

Crystal data
Chemical formulaC15H14N2
Mr222.28
Crystal system, space groupTrigonal, P31
Temperature (K)123
a, c (Å)9.5600 (4), 11.2569 (5)
V (Å3)890.97 (7)
Z3
Radiation typeMo Kα
µ (mm−1)0.07
Crystal size (mm)0.35 × 0.13 × 0.12
Data collection
DiffractometerBruker–Nonius KappaCCD with APEXII detector
diffractometer
Absorption correction–
No. of measured, independent and
observed [I > 2σ(I)] reflections		6729, 1468, 1215
Rint0.068
(sin θ/λ)max (Å−1)0.666
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.046, 0.095, 1.06
No. of reflections1468
No. of parameters155
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.19, −0.19

Computer programs: COLLECT (Bruker, 2008), DENZO-SMN (Otwinowski & Minor, 1997), SIR2004 (Burla et al., 2005), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and Mercury (Macrae, et al., 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3···N1i0.882.042.908 (3)169
Symmetry code: (i) −y, x−y+1, z+1/3.
 

Acknowledgements

Academy Professor Kari Rissanen and the Academy of Finland (project No. 212588 for KR) are gratefully acknowledged for funding. Dr Katri Laihia is thanked for characterization of the NMR spectra.

References

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ISSN: 2056-9890
Volume 67| Part 4| April 2011| Pages o923-o924
doi:10.1107/S1600536811009664
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