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

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ISSN: 2056-9890

4-(4-Methyl­phen­yl)-2-(prop-2-yn-1-yl)phthalazin-1(2H)-one

aDepartment of Studies in Physics, University of Mysore, Manasagangotri, Mysore 570 006, India, and bDepartment of Studies in Chemistry, Mangalore University, Mangalagangotri, Mangalore 574 199, India
*Correspondence e-mail: dr@physics.uni-mysore.ac.in

(Received 26 December 2013; accepted 30 December 2013; online 15 January 2014)

In the title compound, C18H14N2O, the dihedral angle between the methyl­phenyl ring and the phthalazone ring system (r.m.s. deviation = 0.034 Å) is 53.93 (9)°. In the crystal, mol­ecules are connected by C—H⋯O hydrogen bonds, forming chains along [101]. The chains are linked by ππ inter­actions [centroid–centroid distance 3.6990 (12) Å], forming layers parallel to (10-1).

Related literature

For general background and the biological and pharmacological properties of phthalazine derivatives, see: Abd alla et al. (2010[Abd alla, M. S. M., Hegab, M. I., Taleb, N. A. A., Hasabelnaby, S. M. & Goudah, A. (2010). Eur. J. Med. Chem. 45, 1267-1277.]); Awadallah et al. (2012[Awadallah, F. M., El-Eraky, W. I. & Saleh, D. O. (2012). Eur. J. Med. Chem. 52, 14-21.]); Khalil et al. (2009[Khalil, A. M., Berghot, M. A. & Gouda, M. A. (2009). Eur. J. Med. Chem. 44, 4448-4454.]); Kim et al. (2008[Kim, J. S., Rhee, H.-K., Park, H. J., Lee, S. K., Lee, C.-O. & Choo, H.-Y. P. (2008). Bioorg. Med. Chem. 16, 4545-4550.]); Ryu et al. (2007[Ryu, C.-K., Park, R.-E., Ma, M.-Y. & Nho, J.-H. (2007). Bioorg. Med. Chem. Lett. 17, 2477-2580.]). For a related structure, see: Bausch et al. (1997[Bausch, M. J., Robinson, P. D. & Gong, Y. (1997). Acta Cryst. C53, 517-519.]).

[Scheme 1]

Experimental

Crystal data
  • C18H14N2O

  • Mr = 274.31

  • Monoclinic, P 21 /n

  • a = 11.9917 (19) Å

  • b = 9.7116 (16) Å

  • c = 12.602 (2) Å

  • β = 101.285 (7)°

  • V = 1439.2 (4) Å3

  • Z = 4

  • Cu Kα radiation

  • μ = 0.63 mm−1

  • T = 296 K

  • 0.23 × 0.20 × 0.19 mm

Data collection
  • Bruker X8 Proteum diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2013[Bruker (2013). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison,Wisconsin, USA.]) Tmin = 0.864, Tmax = 0.886

  • 8733 measured reflections

  • 2337 independent reflections

  • 2093 reflections with I > 2σ(I)

  • Rint = 0.036

Refinement
  • R[F2 > 2σ(F2)] = 0.044

  • wR(F2) = 0.132

  • S = 1.10

  • 2337 reflections

  • 192 parameters

  • H-atom parameters constrained

  • Δρmax = 0.15 e Å−3

  • Δρmin = −0.15 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C6—H6⋯O1i 0.93 2.45 3.322 (2) 157
Symmetry code: (i) [x-{\script{1\over 2}}, -y-{\script{1\over 2}}, z-{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2013[Bruker (2013). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison,Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2013[Bruker (2013). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison,Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: 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: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Nitrogen heterocyclic compounds have received a great attention because of their wide applicability in different areas, especially drugs (Kim et al., 2008). Phthalazines are an important class of nitrogen heterocyclic compounds that possess exciting pharmacological and biological properties (Khalil et al., 2009). Phthalazines have been reported to possess antifungal (Ryu et al., 2007), antibacterial (Khalil et al., 2009), cytotoxic (Kim et al., 2008), anti-inflammatory (Abd alla et al., 2010), antihypertensive and vasorelaxant (Awadallah et al., 2012) properties. As part of our studies in this area, herewith we report the structure of the title compound.

The ORTEP of the title compound is shown (Fig. 1). The phthalazine ring is nearly planar. The dihedral angle between the methylphenyl ring and the phenyl ring of the phthalazinone moiety is 53.93 (9)°. The bond lengths and bond angles of the title compound are comparable to related structure, 4-(9-fluorenoxy)-2-phenylphthalazin-1(2H)-one (Bausch et al., 1997). In the crystal structure, molecules are connected by intermolecular C—H···O hydrogen bonds (Fig. 2). Also, short contacts of the type ππ are observed [minimum centroid-centroid distance 3.6990 (12) Å].

Related literature top

For general background and the biological and pharmacological properties of phthalazine derivatives, see: Abd alla et al. (2010); Awadallah et al. (2012); Khalil et al. (2009); Kim et al. (2008); Ryu et al. (2007). For a related structure, see: Bausch et al. (1997).

Experimental top

2-(4-Methylbenzoyl)benzoic acid (0.1 mol) is esterified in ethanol (25 ml) in presence of few drops of sulfuric acid. The ethyl 2-(4-methylbenzoyl)benzoate obtained is further refluxed with hydrazine hydrate (5 ml, 98%) in absolute ethanol (50 ml)for 2 hrs. Solid obtained on cooling was filtered off and dried to give 4-(4-methylphenyl)phthalazin-1-ol. A mixture of 4-(4-methylphenyl)phthalazin-1-ol (0.015 mol), anhydrous potassium carbonate (3.04 g, 0.022 mol) and propargylbromide (1.78 g, 0.015 mol) in DMF (25 ml) was stirred at 65 °C for 2 h. After completion of reaction, reaction mixture was poured into ice-cold water. The solid product obtained was purified by column chromatography using n-hexane and ethyl acetate as eluent to get pure compound. Further the compound was recrystallized from ethyl acetate to get the yellow crystals (m.p. 168–170 °C).

Refinement top

The H atoms were placed in calculated positions (C—H = 0.93–0.97 Å) and refined as riding with Uiso(H) = 1.2Ueq(C) or 1.5Ueq(Cmethyl).

Structure description top

Nitrogen heterocyclic compounds have received a great attention because of their wide applicability in different areas, especially drugs (Kim et al., 2008). Phthalazines are an important class of nitrogen heterocyclic compounds that possess exciting pharmacological and biological properties (Khalil et al., 2009). Phthalazines have been reported to possess antifungal (Ryu et al., 2007), antibacterial (Khalil et al., 2009), cytotoxic (Kim et al., 2008), anti-inflammatory (Abd alla et al., 2010), antihypertensive and vasorelaxant (Awadallah et al., 2012) properties. As part of our studies in this area, herewith we report the structure of the title compound.

The ORTEP of the title compound is shown (Fig. 1). The phthalazine ring is nearly planar. The dihedral angle between the methylphenyl ring and the phenyl ring of the phthalazinone moiety is 53.93 (9)°. The bond lengths and bond angles of the title compound are comparable to related structure, 4-(9-fluorenoxy)-2-phenylphthalazin-1(2H)-one (Bausch et al., 1997). In the crystal structure, molecules are connected by intermolecular C—H···O hydrogen bonds (Fig. 2). Also, short contacts of the type ππ are observed [minimum centroid-centroid distance 3.6990 (12) Å].

For general background and the biological and pharmacological properties of phthalazine derivatives, see: Abd alla et al. (2010); Awadallah et al. (2012); Khalil et al. (2009); Kim et al. (2008); Ryu et al. (2007). For a related structure, see: Bausch et al. (1997).

Computing details top

Data collection: APEX2 (Bruker, 2013); cell refinement: SAINT (Bruker, 2013); data reduction: SAINT (Bruker, 2013); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. ORTEP diagram of the title compound with 50% probability ellipsoids.
[Figure 2] Fig. 2. Packing diagram of the title compound, viewed along the c axis.
4-(4-Methylphenyl)-2-(prop-2-yn-1-yl)phthalazin-1(2H)-one top
Crystal data top
C18H14N2OF(000) = 576
Mr = 274.31Dx = 1.266 Mg m3
Monoclinic, P21/nCu Kα radiation, λ = 1.54178 Å
Hall symbol: -P 2ynCell parameters from 2337 reflections
a = 11.9917 (19) Åθ = 4.7–64.6°
b = 9.7116 (16) ŵ = 0.63 mm1
c = 12.602 (2) ÅT = 296 K
β = 101.285 (7)°Block, yellow
V = 1439.2 (4) Å30.23 × 0.20 × 0.19 mm
Z = 4
Data collection top
Bruker X8 Proteum
diffractometer
2337 independent reflections
Radiation source: Bruker MicroStar microfocus rotating anode2093 reflections with I > 2σ(I)
Helios multilayer optics monochromatorRint = 0.036
Detector resolution: 10.7 pixels mm-1θmax = 64.6°, θmin = 4.7°
φ and ω scansh = 1312
Absorption correction: multi-scan
(SADABS; Bruker, 2013)
k = 1011
Tmin = 0.864, Tmax = 0.886l = 814
8733 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.044H-atom parameters constrained
wR(F2) = 0.132 w = 1/[σ2(Fo2) + (0.0698P)2 + 0.2752P]
where P = (Fo2 + 2Fc2)/3
S = 1.10(Δ/σ)max = 0.003
2337 reflectionsΔρmax = 0.15 e Å3
192 parametersΔρmin = 0.15 e Å3
0 restraintsExtinction correction: SHELXL, FC*=KFC[1+0.001XFC2Λ3/SIN(2Θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0090 (9)
Crystal data top
C18H14N2OV = 1439.2 (4) Å3
Mr = 274.31Z = 4
Monoclinic, P21/nCu Kα radiation
a = 11.9917 (19) ŵ = 0.63 mm1
b = 9.7116 (16) ÅT = 296 K
c = 12.602 (2) Å0.23 × 0.20 × 0.19 mm
β = 101.285 (7)°
Data collection top
Bruker X8 Proteum
diffractometer
2337 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2013)
2093 reflections with I > 2σ(I)
Tmin = 0.864, Tmax = 0.886Rint = 0.036
8733 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0440 restraints
wR(F2) = 0.132H-atom parameters constrained
S = 1.10Δρmax = 0.15 e Å3
2337 reflectionsΔρmin = 0.15 e Å3
192 parameters
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

Refinement. Refinement on F2 for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The observed criterion of F2 > σ(F2) is used only for calculating -R-factor-obs 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
O10.19809 (12)0.11059 (16)1.21105 (8)0.0755 (5)
N10.22126 (12)0.03101 (14)0.95663 (10)0.0524 (4)
N20.23069 (12)0.00807 (15)1.06549 (10)0.0548 (5)
C10.07580 (12)0.14488 (16)0.92636 (11)0.0464 (5)
C20.09215 (13)0.17108 (17)1.03779 (11)0.0486 (5)
C30.17640 (14)0.09248 (18)1.11276 (12)0.0536 (5)
C40.14781 (13)0.04216 (16)0.88990 (11)0.0468 (5)
C50.01049 (14)0.21765 (18)0.85760 (13)0.0562 (5)
C60.07462 (15)0.3140 (2)0.89874 (15)0.0645 (6)
C70.05524 (16)0.3416 (2)1.00855 (15)0.0647 (6)
C80.02715 (15)0.27061 (19)1.07770 (14)0.0588 (6)
C90.31525 (16)0.0952 (2)1.13355 (14)0.0646 (6)
C100.43037 (18)0.0402 (2)1.14605 (14)0.0653 (7)
C110.5226 (2)0.0013 (3)1.1548 (2)0.0997 (10)
C120.14520 (13)0.01379 (17)0.77355 (12)0.0473 (5)
C130.13700 (15)0.11933 (18)0.73343 (13)0.0554 (6)
C140.13974 (16)0.1456 (2)0.62603 (13)0.0604 (6)
C150.15141 (14)0.0409 (2)0.55518 (12)0.0567 (6)
C160.15944 (16)0.0918 (2)0.59542 (13)0.0638 (6)
C170.15584 (16)0.11952 (19)0.70219 (13)0.0583 (6)
C180.15649 (17)0.0690 (2)0.43701 (13)0.0708 (7)
H50.024400.200600.783600.0670*
H60.131700.361100.852200.0770*
H70.098100.408301.035300.0780*
H80.039900.288701.151500.0710*
H9A0.313100.186301.101800.0770*
H9B0.295700.104101.204400.0770*
H110.596500.034401.161800.1200*
H130.129500.192200.779400.0660*
H140.133600.235900.601100.0720*
H160.167500.164400.549400.0760*
H170.160600.210100.726500.0700*
H18A0.122100.156500.415800.1060*
H18B0.116200.002100.392200.1060*
H18C0.234400.070200.428700.1060*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0829 (9)0.1064 (11)0.0305 (6)0.0022 (8)0.0054 (6)0.0047 (6)
N10.0592 (8)0.0597 (8)0.0341 (7)0.0033 (6)0.0011 (6)0.0022 (6)
N20.0602 (8)0.0656 (9)0.0324 (7)0.0008 (7)0.0062 (6)0.0062 (6)
C10.0452 (8)0.0546 (9)0.0356 (8)0.0106 (7)0.0011 (6)0.0001 (6)
C20.0463 (8)0.0616 (10)0.0347 (8)0.0120 (7)0.0004 (6)0.0012 (7)
C30.0546 (9)0.0684 (11)0.0338 (8)0.0099 (8)0.0010 (7)0.0002 (7)
C40.0485 (8)0.0534 (9)0.0340 (8)0.0077 (7)0.0029 (6)0.0022 (6)
C50.0558 (9)0.0676 (11)0.0398 (8)0.0020 (8)0.0041 (7)0.0023 (7)
C60.0544 (10)0.0732 (12)0.0611 (11)0.0037 (9)0.0001 (8)0.0053 (9)
C70.0560 (10)0.0724 (12)0.0646 (11)0.0008 (9)0.0089 (8)0.0059 (9)
C80.0555 (9)0.0757 (12)0.0446 (9)0.0087 (8)0.0084 (7)0.0102 (8)
C90.0735 (12)0.0688 (12)0.0429 (9)0.0040 (9)0.0094 (8)0.0117 (8)
C100.0669 (12)0.0716 (12)0.0519 (10)0.0129 (9)0.0015 (8)0.0003 (8)
C110.0672 (15)0.0930 (17)0.135 (2)0.0067 (13)0.0102 (14)0.0109 (15)
C120.0463 (8)0.0578 (9)0.0338 (8)0.0043 (7)0.0016 (6)0.0019 (6)
C130.0683 (10)0.0552 (10)0.0416 (9)0.0007 (8)0.0081 (7)0.0051 (7)
C140.0725 (11)0.0613 (10)0.0462 (9)0.0006 (8)0.0089 (8)0.0060 (8)
C150.0498 (9)0.0820 (12)0.0360 (8)0.0015 (8)0.0027 (7)0.0015 (8)
C160.0757 (12)0.0726 (12)0.0424 (9)0.0067 (9)0.0102 (8)0.0125 (8)
C170.0726 (11)0.0572 (10)0.0434 (9)0.0116 (8)0.0075 (8)0.0021 (7)
C180.0664 (11)0.1084 (16)0.0362 (9)0.0050 (11)0.0064 (8)0.0095 (9)
Geometric parameters (Å, º) top
O1—C31.2275 (18)C14—C151.378 (3)
N1—N21.3725 (18)C15—C161.381 (3)
N1—C41.303 (2)C15—C181.527 (2)
N2—C31.373 (2)C16—C171.381 (2)
N2—C91.463 (2)C5—H50.9300
C1—C21.4026 (19)C6—H60.9300
C1—C41.452 (2)C7—H70.9300
C1—C51.404 (2)C8—H80.9300
C2—C31.457 (2)C9—H9A0.9700
C2—C81.396 (2)C9—H9B0.9700
C4—C121.486 (2)C11—H110.9300
C5—C61.375 (3)C13—H130.9300
C6—C71.384 (3)C14—H140.9300
C7—C81.369 (3)C16—H160.9300
C9—C101.460 (3)C17—H170.9300
C10—C111.162 (3)C18—H18A0.9600
C12—C131.385 (2)C18—H18B0.9600
C12—C171.387 (2)C18—H18C0.9600
C13—C141.384 (2)
N2—N1—C4118.01 (13)C15—C16—C17121.75 (17)
N1—N2—C3126.58 (13)C12—C17—C16120.78 (17)
N1—N2—C9113.85 (13)C1—C5—H5120.00
C3—N2—C9119.36 (13)C6—C5—H5120.00
C2—C1—C4117.79 (13)C5—C6—H6120.00
C2—C1—C5117.93 (14)C7—C6—H6120.00
C4—C1—C5124.26 (13)C6—C7—H7120.00
C1—C2—C3119.84 (14)C8—C7—H7120.00
C1—C2—C8120.52 (14)C2—C8—H8120.00
C3—C2—C8119.64 (13)C7—C8—H8120.00
O1—C3—N2121.00 (16)N2—C9—H9A109.00
O1—C3—C2124.23 (16)N2—C9—H9B109.00
N2—C3—C2114.77 (13)C10—C9—H9A109.00
N1—C4—C1122.64 (13)C10—C9—H9B109.00
N1—C4—C12114.62 (14)H9A—C9—H9B108.00
C1—C4—C12122.73 (13)C10—C11—H11180.00
C1—C5—C6120.59 (15)C12—C13—H13119.00
C5—C6—C7120.79 (17)C14—C13—H13120.00
C6—C7—C8119.87 (18)C13—C14—H14119.00
C2—C8—C7120.25 (16)C15—C14—H14119.00
N2—C9—C10112.59 (16)C15—C16—H16119.00
C9—C10—C11178.6 (2)C17—C16—H16119.00
C4—C12—C13121.31 (14)C12—C17—H17120.00
C4—C12—C17121.03 (15)C16—C17—H17120.00
C13—C12—C17117.61 (14)C15—C18—H18A109.00
C12—C13—C14121.04 (16)C15—C18—H18B109.00
C13—C14—C15121.49 (17)C15—C18—H18C110.00
C14—C15—C16117.33 (15)H18A—C18—H18B109.00
C14—C15—C18121.90 (17)H18A—C18—H18C109.00
C16—C15—C18120.77 (16)H18B—C18—H18C109.00
C4—N1—N2—C35.4 (2)C8—C2—C3—O12.6 (3)
C4—N1—N2—C9179.97 (16)C8—C2—C3—N2176.34 (16)
N2—N1—C4—C10.6 (2)C1—C2—C8—C71.5 (3)
N2—N1—C4—C12178.36 (14)C3—C2—C8—C7177.55 (17)
N1—N2—C3—O1174.12 (16)N1—C4—C12—C1350.0 (2)
N1—N2—C3—C26.9 (2)N1—C4—C12—C17127.20 (17)
C9—N2—C3—O10.3 (3)C1—C4—C12—C13131.06 (17)
C9—N2—C3—C2178.71 (15)C1—C4—C12—C1751.7 (2)
N1—N2—C9—C1083.42 (18)C1—C5—C6—C70.2 (3)
C3—N2—C9—C1091.67 (19)C5—C6—C7—C81.3 (3)
C4—C1—C2—C32.2 (2)C6—C7—C8—C20.4 (3)
C4—C1—C2—C8178.72 (15)C4—C12—C13—C14177.07 (16)
C5—C1—C2—C3176.58 (15)C17—C12—C13—C140.2 (3)
C5—C1—C2—C82.5 (2)C4—C12—C17—C16176.53 (17)
C2—C1—C4—N14.1 (2)C13—C12—C17—C160.8 (3)
C2—C1—C4—C12174.76 (15)C12—C13—C14—C150.4 (3)
C5—C1—C4—N1174.61 (16)C13—C14—C15—C160.5 (3)
C5—C1—C4—C126.5 (2)C13—C14—C15—C18178.98 (17)
C2—C1—C5—C61.6 (2)C14—C15—C16—C170.1 (3)
C4—C1—C5—C6179.67 (16)C18—C15—C16—C17179.55 (18)
C1—C2—C3—O1178.30 (17)C15—C16—C17—C120.7 (3)
C1—C2—C3—N22.7 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6···O1i0.932.453.322 (2)157
Symmetry code: (i) x1/2, y1/2, z1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6···O1i0.932.453.322 (2)157
Symmetry code: (i) x1/2, y1/2, z1/2.
 

Acknowledgements

The authors are grateful to the IOE, University of Mysore, for providing the single-crystal X-ray diffraction facility. MKU is grateful to the DST, New Delhi, for the award of an INSPIRE Fellowship. DR acknowledges the UGC, New Delhi, for financial support under the Major Research Project Scheme [No. F.41–882/2012 (SR)].

References

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