3-Methyl-1,2,4-triazolo[3,4-a]phthalazine monohydrate

Dutkiewicz, G.; Chidan Kumar, C.S.; Yathirajan, H.S.; Mayekar, A.N.; Kubicki, M.

doi:10.1107/S1600536809040677

organic compounds

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Volume 65| Part 11| November 2009| Page o2694

https://doi.org/10.1107/S1600536809040677

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3-Methyl-1,2,4-triazolo[3,4-a]phthalazine monohydrate

Grzegorz Dutkiewicz,^a C. S. Chidan Kumar,^b H. S. Yathirajan,^b A. N. Mayekar ^c and Maciej Kubicki ^a ^*

^aDepartment of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60-780 Poznań, Poland, ^bDepartment of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore 570 006, India, and ^cSequent Scientific Ltd, New Mangalore 575 011, India
^*Correspondence e-mail: mkubicki@amu.edu.pl

(Received 2 October 2009; accepted 6 October 2009; online 10 October 2009)

In the crystal structure of the title compound, C₁₀H₈N₄·H₂O, the organic molecules are approximately planar [maximum deviation from the least-squares plane = 0.041 (2) Å]. Two molecules are connected by two water molecules via O—H⋯N hydrogen bonding into dimers, which are located around centres of inversion. In the crystal, molecules are stacked in the a-axis direction, with mean distances between the π systems of 3.43 (1) and 3.46 (1) Å [centroid–centroid distances are 3.604 (2) and 3.591 (2) Å].

Related literature

For general background to phthalazines, see: Cheng et al. (1999 ); Coates (1999 ); De Stevens (1981 ); Shubin et al. (2004 ); Tarzia et al. (1989 ); Yatani et al. (2001 ). For related structures, see: Boulanger et al. (1991 ); Burton-Pye et al. (2005 ); Zimmer et al. (1995 ). For a description of the Cambridge Structural Database, see: Allen (2002 ).

Experimental

Crystal data

C₁₀H₈N₄·H₂O
M_r = 202.22
Triclinic, $[P \overline 1]$
a = 7.3009 (9) Å
b = 7.9253 (9) Å
c = 9.2755 (10) Å
α = 109.663 (10)°
β = 104.91 (1)°
γ = 95.830 (9)°
V = 477.83 (10) Å³
Z = 2
Cu Kα radiation
μ = 0.80 mm⁻¹
T = 295 K
0.4 × 0.2 × 0.1 mm

Data collection

Oxford Diffraction SuperNova (single source at offset) Atlas diffractometer
Absorption correction: multi-scan (CrysAlis Pro; Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis Pro. Oxford Diffraction Ltd, Yarnton, England.]$ ) T_min = 0.831, T_max = 0.932
2893 measured reflections
1772 independent reflections
1615 reflections with I > 2σ(I)
R_int = 0.024

Refinement

R[F² > 2σ(F²)] = 0.057
wR(F²) = 0.147
S = 1.12
1772 reflections
164 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.20 e Å⁻³
Δρ_min = −0.17 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1W—H1W2⋯N1	0.92 (5)	2.08 (5)	2.987 (2)	168 (4)
O1W—H1W1⋯N2ⁱ	0.83 (3)	2.21 (3)	3.043 (2)	177 (3)
Symmetry code: (i) -x, -y+1, -z.

Data collection: CrysAlis Pro (Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis Pro. Oxford Diffraction Ltd, Yarnton, England.]$ ); cell refinement: CrysAlis Pro; data reduction: CrysAlis Pro; program(s) used to solve structure: SIR92 (Altomare et al., 1993 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: XP (Siemens, 1989 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536809040677/nc2160sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536809040677/nc2160Isup2.hkl

checkCIF report

Comment top

The practical interest upon phthalazine derivatives is based on their widespread applications (Coates, 1999). They are commonly used as ligands in transition metal catalysis (e.g., Yatani et al., 2001), as chemiluminescent materials (Shubin et al., 2004) and for optical applications (Cheng et al., 1999). The chemistry of phthalazine derivatives has been of increasing interest since many of these compounds have found chemotherapeutic applications, especially as antihypertensive agents (De Stevens, 1981). 3-substituted 1,2,4-triazolo[3,4-a]phthalazines have been described as high affinity ligands for benzodiazepine receptor site (e.g., Tarzia et al., 1989).

In the Cambridge Database (Allen, 2002; ver. 5.30, November 2008) there are only four structures with 1,2,4-triazolo[3,4-a]phthalazine units. This includes 3-chloromethyl-1,2,4-triazolophthalazine (Burton-Pye et al., 2005), 3-(p-methoxyphenyl)triazolo(4,3 - a)phthalazine (Boulanger et al., 1991), 3-(p-methoxyphenyl)-6-(N,N-bis(2-methoxyethyl)amino)triazolo(4,3 - a)phthalazine (Boulanger et al., 1991), and 3-butyl-s-triazolo(3,4 - a)phthalazine (Zimmer et al., 1995). Here we present the X-ray structural analysis of the hydrate of 3-methyl[1,2,4]triazolo[3,4-a]phthalazine.

The molecules are almost planar with maximum deviation from the least-squares plane through all 13 ring atoms of 0.041 (2) Å (Fig. 1). The dihedral angle between the planes of the phenyl and the 1,2,4-triazole rings amount to 2.84 (7)°.

In the crystal the principal motif is built of two molecules of 3-methyl[1,2,4]triazolo[3,4-a]phthalazine and two water molecules, which are connected by means of O—H···N hydrogen bonds into centrosymmetric dimers which can be described according to the graph set notation as R₄⁴(10), cf. (Fig. 2). The planar molecules are stacked in a head-to-tail manner in the direction of the crystallographic a-axis with distances between the subsequent mean planes of 3.43 (1)Å and 3.46 (1)Å.

Related literature top

For general background to phthalazines, see: Cheng et al. (1999); Coates (1999); De Stevens (1981); Shubin et al. (2004); Tarzia et al. (1989); Yatani et al. (2001). For related structures, see: Boulanger et al. (1991); Burton-Pye et al. (2005); Zimmer et al. (1995). For a description of the Cambridge Structural Database, see: Allen (2002).

Experimental top

1-Hydrazinophthalazine (2 g, 12.5 mmol) in 10 ml acetic acid was refluxed for 4 h. The reaction mixture was quenched to ice cold water and the solid separated was collected by filteration. The solid obtained was crystallized from methanol. Crystals for x-ray measurements were grown by a slow evaporation of ethyl acetate solution (m.p.: 421–423 K).

Structure description top

For general background to phthalazines, see: Cheng et al. (1999); Coates (1999); De Stevens (1981); Shubin et al. (2004); Tarzia et al. (1989); Yatani et al. (2001). For related structures, see: Boulanger et al. (1991); Burton-Pye et al. (2005); Zimmer et al. (1995). For a description of the Cambridge Structural Database, see: Allen (2002).

Computing details top

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: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP (Siemens, 1989); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. View of the dimers in the crystal structure of the title compound with labelling and displacement ellipsoids drawn at 50% probability level. Hydrogen atoms are depicted as spheres with arbitrary radii and hydrogen bonding is shown as dashed lines. Symmetry code: (i) -x,1 - y,-z.
	Fig. 2. Two mutually perpendicular views of the stacking in the crystal structure of the title compound.

3-Methyl-1,2,4-triazolo[3,4-a]phthalazine monohydrate top

Crystal data top

C₁₀H₈N₄·H₂O	Z = 2
M_r = 202.22	F(000) = 212
Triclinic, P1	D_x = 1.405 Mg m⁻³
Hall symbol: -P 1	Cu Kα radiation, λ = 1.5418 Å
a = 7.3009 (9) Å	Cell parameters from 2647 reflections
b = 7.9253 (9) Å	θ = 6.4–75.6°
c = 9.2755 (10) Å	µ = 0.80 mm⁻¹
α = 109.663 (10)°	T = 295 K
β = 104.91 (1)°	Block, colourless
γ = 95.830 (9)°	0.4 × 0.2 × 0.1 mm
V = 477.83 (10) Å³

Data collection top

Oxford Diffraction SuperNova (single source at offset) Atlas diffractometer	1772 independent reflections
Radiation source: Nova (Cu) X-ray Source	1615 reflections with I > 2σ(I)
Mirror monochromator	R_int = 0.024
Detector resolution: 5.2679 pixels mm^-1	θ_max = 70.0°, θ_min = 6.4°
ω scans	h = −7→8
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)	k = −9→9
T_min = 0.831, T_max = 0.932	l = −10→11
2893 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.057	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.147	H atoms treated by a mixture of independent and constrained refinement
S = 1.12	w = 1/[σ²(F_o²) + (0.07P)² + 0.128P] where P = (F_o² + 2F_c²)/3
1772 reflections	(Δ/σ)_max < 0.001
164 parameters	Δρ_max = 0.20 e Å⁻³
0 restraints	Δρ_min = −0.17 e Å⁻³

Crystal data top

C₁₀H₈N₄·H₂O	γ = 95.830 (9)°
M_r = 202.22	V = 477.83 (10) Å³
Triclinic, P1	Z = 2
a = 7.3009 (9) Å	Cu Kα radiation
b = 7.9253 (9) Å	µ = 0.80 mm⁻¹
c = 9.2755 (10) Å	T = 295 K
α = 109.663 (10)°	0.4 × 0.2 × 0.1 mm
β = 104.91 (1)°

Data collection top

Oxford Diffraction SuperNova (single source at offset) Atlas diffractometer	1772 independent reflections
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)	1615 reflections with I > 2σ(I)
T_min = 0.831, T_max = 0.932	R_int = 0.024
2893 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.057	0 restraints
wR(F²) = 0.147	H atoms treated by a mixture of independent and constrained refinement
S = 1.12	Δρ_max = 0.20 e Å⁻³
1772 reflections	Δρ_min = −0.17 e Å⁻³
164 parameters

Special details top

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 (Å²) top

	x	y	z	U_iso*/U_eq
N1	0.0820 (2)	0.4413 (2)	0.25290 (18)	0.0576 (5)
N2	−0.0116 (2)	0.2599 (2)	0.16838 (18)	0.0585 (5)
C3	0.0258 (2)	0.1699 (3)	0.2642 (2)	0.0504 (4)
C31	−0.0377 (3)	−0.0275 (3)	0.2252 (2)	0.0629 (5)
H31A	−0.1301	−0.0825	0.1193	0.094*
H31B	−0.0966	−0.0436	0.3024	0.094*
H31C	0.0722	−0.0847	0.2287	0.094*
N4	0.1420 (2)	0.2902 (2)	0.41193 (16)	0.0455 (4)
N5	0.2127 (2)	0.2489 (2)	0.54647 (17)	0.0530 (4)
C6	0.3218 (3)	0.3879 (3)	0.6698 (2)	0.0533 (5)
H6	0.372 (3)	0.360 (3)	0.765 (3)	0.070 (6)*
C7	0.3736 (2)	0.5716 (2)	0.6764 (2)	0.0477 (4)
C8	0.4993 (3)	0.7118 (3)	0.8151 (2)	0.0562 (5)
H8	0.557 (4)	0.683 (3)	0.913 (3)	0.080 (7)*
C9	0.5466 (3)	0.8835 (3)	0.8153 (3)	0.0600 (5)
H9	0.636 (3)	0.978 (3)	0.909 (3)	0.067 (6)*
C10	0.4682 (3)	0.9207 (3)	0.6786 (3)	0.0613 (5)
H10	0.506 (4)	1.043 (4)	0.685 (3)	0.080 (7)*
C11	0.3434 (3)	0.7866 (3)	0.5412 (2)	0.0573 (5)
H11	0.283 (3)	0.805 (3)	0.447 (3)	0.074 (7)*
C12	0.2970 (2)	0.6096 (2)	0.5382 (2)	0.0467 (4)
C13	0.1741 (2)	0.4575 (3)	0.4000 (2)	0.0466 (4)
O1W	0.2725 (3)	0.6362 (3)	0.0877 (2)	0.0876 (6)
H1W2	0.198 (6)	0.571 (6)	0.125 (5)	0.143 (14)*
H1W1	0.197 (4)	0.662 (4)	0.018 (4)	0.092 (9)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0568 (9)	0.0734 (11)	0.0449 (8)	0.0125 (8)	0.0080 (7)	0.0313 (8)
N2	0.0558 (9)	0.0759 (11)	0.0431 (8)	0.0143 (8)	0.0092 (6)	0.0263 (8)
C3	0.0470 (9)	0.0637 (11)	0.0399 (9)	0.0137 (8)	0.0129 (7)	0.0185 (8)
C31	0.0655 (12)	0.0629 (12)	0.0510 (10)	0.0102 (9)	0.0132 (9)	0.0145 (9)
N4	0.0483 (8)	0.0565 (8)	0.0363 (7)	0.0158 (6)	0.0120 (6)	0.0228 (6)
N5	0.0653 (9)	0.0569 (9)	0.0416 (8)	0.0159 (7)	0.0124 (7)	0.0265 (7)
C6	0.0634 (11)	0.0610 (11)	0.0382 (9)	0.0159 (8)	0.0103 (8)	0.0253 (8)
C7	0.0495 (9)	0.0572 (10)	0.0413 (9)	0.0157 (7)	0.0159 (7)	0.0218 (8)
C8	0.0594 (11)	0.0645 (11)	0.0429 (9)	0.0142 (9)	0.0142 (8)	0.0191 (8)
C9	0.0565 (11)	0.0608 (11)	0.0555 (11)	0.0067 (9)	0.0189 (9)	0.0136 (9)
C10	0.0616 (11)	0.0558 (11)	0.0717 (13)	0.0122 (9)	0.0251 (10)	0.0274 (10)
C11	0.0586 (11)	0.0634 (11)	0.0599 (11)	0.0164 (8)	0.0184 (9)	0.0345 (9)
C12	0.0444 (8)	0.0585 (10)	0.0451 (9)	0.0165 (7)	0.0168 (7)	0.0255 (8)
C13	0.0454 (8)	0.0595 (10)	0.0435 (9)	0.0164 (7)	0.0150 (7)	0.0275 (8)
O1W	0.0682 (10)	0.1226 (15)	0.0838 (12)	0.0115 (9)	0.0052 (8)	0.0695 (12)

Geometric parameters (Å, º) top

N1—C13	1.312 (2)	C7—C8	1.398 (3)
N1—N2	1.384 (2)	C7—C12	1.404 (2)
N2—C3	1.309 (2)	C8—C9	1.369 (3)
C3—N4	1.365 (2)	C8—H8	1.01 (3)
C3—C31	1.476 (3)	C9—C10	1.391 (3)
C31—H31A	0.9600	C9—H9	0.96 (2)
C31—H31B	0.9600	C10—C11	1.370 (3)
C31—H31C	0.9600	C10—H10	0.96 (3)
N4—C13	1.369 (2)	C11—C12	1.399 (3)
N4—N5	1.3818 (18)	C11—H11	0.94 (3)
N5—C6	1.289 (2)	C12—C13	1.432 (3)
C6—C7	1.443 (3)	O1W—H1W2	0.92 (5)
C6—H6	0.97 (2)	O1W—H1W1	0.83 (3)

C13—N1—N2	107.24 (15)	C12—C7—C6	118.75 (16)
C3—N2—N1	108.84 (14)	C9—C8—C7	120.13 (18)
N2—C3—N4	108.18 (16)	C9—C8—H8	121.1 (14)
N2—C3—C31	127.98 (17)	C7—C8—H8	118.7 (14)
N4—C3—C31	123.82 (16)	C8—C9—C10	120.41 (19)
C3—C31—H31A	109.5	C8—C9—H9	119.8 (14)
C3—C31—H31B	109.5	C10—C9—H9	119.8 (14)
H31A—C31—H31B	109.5	C11—C10—C9	120.85 (19)
C3—C31—H31C	109.5	C11—C10—H10	122.1 (15)
H31A—C31—H31C	109.5	C9—C10—H10	117.0 (15)
H31B—C31—H31C	109.5	C10—C11—C12	119.35 (18)
C3—N4—C13	106.81 (14)	C10—C11—H11	124.5 (15)
C3—N4—N5	126.01 (15)	C12—C11—H11	116.2 (15)
C13—N4—N5	127.18 (15)	C11—C12—C7	120.10 (18)
C6—N5—N4	113.22 (14)	C11—C12—C13	124.20 (16)
N5—C6—C7	126.56 (16)	C7—C12—C13	115.70 (16)
N5—C6—H6	113.6 (14)	N1—C13—N4	108.93 (16)
C7—C6—H6	119.8 (14)	N1—C13—C12	132.48 (17)
C8—C7—C12	119.14 (17)	N4—C13—C12	118.57 (15)
C8—C7—C6	122.10 (16)	H1W2—O1W—H1W1	107 (3)

C13—N1—N2—C3	−0.4 (2)	C10—C11—C12—C7	1.7 (3)
N1—N2—C3—N4	0.5 (2)	C10—C11—C12—C13	−177.70 (16)
N1—N2—C3—C31	−177.91 (17)	C8—C7—C12—C11	−1.3 (3)
N2—C3—N4—C13	−0.45 (19)	C6—C7—C12—C11	179.58 (15)
C31—C3—N4—C13	178.04 (16)	C8—C7—C12—C13	178.19 (14)
N2—C3—N4—N5	179.64 (14)	C6—C7—C12—C13	−0.9 (2)
C31—C3—N4—N5	−1.9 (3)	N2—N1—C13—N4	0.06 (19)
C3—N4—N5—C6	178.98 (16)	N2—N1—C13—C12	178.52 (17)
C13—N4—N5—C6	−0.9 (2)	C3—N4—C13—N1	0.23 (19)
N4—N5—C6—C7	−0.6 (3)	N5—N4—C13—N1	−179.86 (14)
N5—C6—C7—C8	−177.53 (18)	C3—N4—C13—C12	−178.47 (13)
N5—C6—C7—C12	1.6 (3)	N5—N4—C13—C12	1.4 (3)
C12—C7—C8—C9	0.0 (3)	C11—C12—C13—N1	0.7 (3)
C6—C7—C8—C9	179.10 (17)	C7—C12—C13—N1	−178.71 (17)
C7—C8—C9—C10	0.8 (3)	C11—C12—C13—N4	179.08 (15)
C8—C9—C10—C11	−0.4 (3)	C7—C12—C13—N4	−0.4 (2)
C9—C10—C11—C12	−0.9 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1W2···N1	0.92 (5)	2.08 (5)	2.987 (2)	168 (4)
O1W—H1W1···N2ⁱ	0.83 (3)	2.21 (3)	3.043 (2)	177 (3)

Symmetry code: (i) −x, −y+1, −z.

Experimental details

Crystal data
Chemical formula	C₁₀H₈N₄·H₂O
M_r	202.22
Crystal system, space group	Triclinic, P1
Temperature (K)	295
a, b, c (Å)	7.3009 (9), 7.9253 (9), 9.2755 (10)
α, β, γ (°)	109.663 (10), 104.91 (1), 95.830 (9)
V (Å³)	477.83 (10)
Z	2
Radiation type	Cu Kα
µ (mm⁻¹)	0.80
Crystal size (mm)	0.4 × 0.2 × 0.1

Data collection
Diffractometer	Oxford Diffraction SuperNova (single source at offset) Atlas
Absorption correction	Multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)
T_min, T_max	0.831, 0.932
No. of measured, independent and observed [I > 2σ(I)] reflections	2893, 1772, 1615
R_int	0.024
(sin θ/λ)_max (Å⁻¹)	0.609

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.057, 0.147, 1.12
No. of reflections	1772
No. of parameters	164
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.20, −0.17

Computer programs: CrysAlis PRO (Oxford Diffraction, 2009), SIR92 (Altomare et al., 1993), SHELXL97 (Sheldrick, 2008), XP (Siemens, 1989).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1W2···N1	0.92 (5)	2.08 (5)	2.987 (2)	168 (4)
O1W—H1W1···N2ⁱ	0.83 (3)	2.21 (3)	3.043 (2)	177 (3)

Symmetry code: (i) −x, −y+1, −z.

Acknowledgements

CSC thanks the University of Mysore for research facilities.

References

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