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

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ISSN: 2056-9890

2-Chloro-9-iso­propyl-N,N-di­methyl-9H-purin-6-amine

aDepartment of Chemistry, Faculty of Technology, Tomas Bata University in Zlin, Nám. T. G. Masaryka 275, Zlín,762 72, Czech Republic, and bDepartment of Chemistry, Faculty of Science, Masaryk University in Brno, Kamenice 5, Brno-Bohunice, 625 00, Czech Republic
*Correspondence e-mail: rvicha@ft.utb.cz

(Received 19 March 2010; accepted 29 March 2010; online 2 April 2010)

In the title compound, C10H14ClN5, the imidazole and pyrimidine rings are essentially planar [maximum deviation = 0.0013 (14) and 0.0207 (13) Å, respectively]. In the crystal, the mol­ecules are linked by weak C—H⋯N inter­actions into chains parallel to the c axis and the crystal packing is stabilized by additional weak C—H⋯N and C—H⋯Cl inter­actions.

Related literature

The title compound was prepared according to a modification of the procedure of Fiorini & Abel (1998[Fiorini, M. T. & Abel, Ch. (1998). Tetrahedron Lett. 39, 1827-1830.]). For the synthesis and/or biological activity of related compounds, see: Legraverend & Grierson (2006[Legraverend, M. & Grierson, D. S. (2006). Bioorg. Med. Chem. 14, 3987-4006.]). For related structures, see: Kubicki & Codding (2001[Kubicki, M. & Codding, P. W. (2001). Acta Cryst. E57, o332-o334.]); Trávníček & Popa (2007[Trávníček, Z. & Popa, I. (2007). Acta Cryst. E63, o728-o730.]); Rouchal et al. (2009a[Rouchal, M., Nečas, M., de Carvalho, F. P. & Vícha, R. (2009a). Acta Cryst. E65, o298-o299.],b[Rouchal, M., Nečas, M. & Vícha, R. (2009b). Acta Cryst. E65, o1268.],c[Rouchal, M., Nečas, M. & Vícha, R. (2009c). Acta Cryst. E65, o1676.]).

[Scheme 1]

Experimental

Crystal data
  • C10H14ClN5

  • Mr = 239.71

  • Monoclinic, P 21 /c

  • a = 12.0483 (3) Å

  • b = 8.7689 (2) Å

  • c = 11.5538 (3) Å

  • β = 109.965 (3)°

  • V = 1147.30 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.31 mm−1

  • T = 120 K

  • 0.40 × 0.40 × 0.30 mm

Data collection
  • Oxford Diffraction Xcalibur (Sapphire2 large Be window) diffractometer

  • Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis RED and CrysAlis CCD. Oxford Diffraction Ltd, Yarnton, England.]) Tmin = 0.968, Tmax = 1.000

  • 13393 measured reflections

  • 2022 independent reflections

  • 1798 reflections with I > 2σ(I)

  • Rint = 0.016

Refinement
  • R[F2 > 2σ(F2)] = 0.025

  • wR(F2) = 0.068

  • S = 1.05

  • 2022 reflections

  • 149 parameters

  • H-atom parameters constrained

  • Δρmax = 0.21 e Å−3

  • Δρmin = −0.18 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C4—H4A⋯N1i 0.95 2.49 3.3728 (18) 154
C7—H7C⋯Cl1ii 0.98 2.91 3.5981 (14) 128
C7—H7B⋯N3iii 0.98 2.75 3.584 (2) 143
C9—H9A⋯N3iv 0.98 2.73 3.6664 (18) 161
Symmetry codes: (i) [x, -y-{\script{1\over 2}}, z+{\script{1\over 2}}]; (ii) [x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]; (iii) [-x+1, y+{\script{1\over 2}}, -z+{\script{3\over 2}}]; (iv) [x, -y-{\script{1\over 2}}, z-{\script{1\over 2}}].

Data collection: CrysAlis CCD (Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis RED and CrysAlis CCD. Oxford Diffraction Ltd, Yarnton, England.]); cell refinement: CrysAlis RED (Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis RED and CrysAlis CCD. Oxford Diffraction Ltd, Yarnton, England.]); data reduction: CrysAlis RED; 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: 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


Comment top

The heterocyclic system, imidazo[4,5-d]pyrimidine, commonly known as purine, was first named by Emil Fisher at the turn of the 19th century. A large number of variously substituted purines exhibit a wide range of biological activities (Legraverend & Grierson, 2006). They act as interferon inducers, adenosine receptor ligands, inhibitors of microtubule assembly, protein kinases, sulfotransferases and phosphodiesterases. The title molecule was prepared as a part of our research into the synthesis of novel trisubstituted purines.

The asymmetric unit of the title compound consists of a single purine molecule. Both imidazole and pyrimidine rings are nearly planar with maximum deviations from the mean plane being 0.0013 (14) Å for C4 (imidazole ring) and 0.0207 (13) Å for C2 (pyrimidine ring). Both carbon atoms of the dimethylamino substituent lie essentially in the pyrimidine mean plane as demonstrated by torsion angles C3—C2—N5—C7 and C3—C2—N5—C6, which are 4.3 (2)° and 175.90 (13)°, respectively. The torsion angle describing the orientation of isopropyl and purine ring, H8A—C8—N4—C4 is -163.55 (13)°. Molecules are linked into chains along the c axis by weak C4—H4···N1 interactions (Table 1, Fig. 2). Crystal packing is further stabilised by short C—H···N and C—H···Cl contacts (Table 1).

Related literature top

The title compound was prepared according to a modified procedure of Fiorini & Abel (1998). For the synthesis and/or biological activity of related compounds, see: Legraverend & Grierson (2006). For related structures, see: Kubicki & Codding (2001); Trávníček & Popa (2007); Rouchal et al. (2009a,b,c).

Experimental top

The title compound was prepared according to a slightly modified literature procedure (Fiorini & Abel, 1998). 2,6-Dichloro-9-(propan-2-yl)-9H-purine (0.87 mmol, 196 mg) and methylamine hydrochloride (0.91 mmol, 61.5 mg) were dissolved in a mixture of DMF (2.5 ml) and N-ethyl-N-isopropylpropan-2-amine (1.74 mmol, 225 mg). The resulting solution was stirred at 90 °C for 2 hours. Subsequently, the mixture was diluted with water and extracted with diethyl ether. Combined organic layers were washed twice with brine and dried over Na2SO4. Crude product consisting of two compounds with relative abundances of 43% and 57% according to GC were obtained after evaporation of the solvent in vacuum. The products were identified as N-methyl and N,N-dimethyl derivatives. Column chromatography (silica gel; petroleum ether/ethyl acetate, v/v, 1/1) yielded the latter as a colourless crystalline powder (105 mg, 54%, mp 418–422 K). The crystal used for data collection was grown by spontaneous evaporation from deuterochloroform at room temperature.

Structure description top

The heterocyclic system, imidazo[4,5-d]pyrimidine, commonly known as purine, was first named by Emil Fisher at the turn of the 19th century. A large number of variously substituted purines exhibit a wide range of biological activities (Legraverend & Grierson, 2006). They act as interferon inducers, adenosine receptor ligands, inhibitors of microtubule assembly, protein kinases, sulfotransferases and phosphodiesterases. The title molecule was prepared as a part of our research into the synthesis of novel trisubstituted purines.

The asymmetric unit of the title compound consists of a single purine molecule. Both imidazole and pyrimidine rings are nearly planar with maximum deviations from the mean plane being 0.0013 (14) Å for C4 (imidazole ring) and 0.0207 (13) Å for C2 (pyrimidine ring). Both carbon atoms of the dimethylamino substituent lie essentially in the pyrimidine mean plane as demonstrated by torsion angles C3—C2—N5—C7 and C3—C2—N5—C6, which are 4.3 (2)° and 175.90 (13)°, respectively. The torsion angle describing the orientation of isopropyl and purine ring, H8A—C8—N4—C4 is -163.55 (13)°. Molecules are linked into chains along the c axis by weak C4—H4···N1 interactions (Table 1, Fig. 2). Crystal packing is further stabilised by short C—H···N and C—H···Cl contacts (Table 1).

The title compound was prepared according to a modified procedure of Fiorini & Abel (1998). For the synthesis and/or biological activity of related compounds, see: Legraverend & Grierson (2006). For related structures, see: Kubicki & Codding (2001); Trávníček & Popa (2007); Rouchal et al. (2009a,b,c).

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2009); cell refinement: CrysAlis RED (Oxford Diffraction, 2009); data reduction: CrysAlis RED (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); 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. An ellipsoid plot (50% probability) of the asymmetric unit. Hydrogen atoms are represented as arbitrary spheres.
[Figure 2] Fig. 2. A view of the crystal structure showing chains parallel to the a-axis linked via C—H···N contacts (dotted lines). H-atoms (except those which are involved in H-bonding) have been omitted for clarity.
2-Chloro-9-isopropyl-N,N-dimethyl-9H-purin-6-amine top
Crystal data top
C10H14ClN5F(000) = 504
Mr = 239.71Dx = 1.388 Mg m3
Monoclinic, P21/cMelting point = 422–418 K
Hall symbol: -P 2ybcMo Kα radiation, λ = 0.7107 Å
a = 12.0483 (3) ÅCell parameters from 8720 reflections
b = 8.7689 (2) Åθ = 2.9–27.3°
c = 11.5538 (3) ŵ = 0.31 mm1
β = 109.965 (3)°T = 120 K
V = 1147.30 (5) Å3Block, colourless
Z = 40.40 × 0.40 × 0.30 mm
Data collection top
Oxford Diffraction Xcalibur (Sapphire2 large Be window)
diffractometer
2022 independent reflections
Radiation source: Enhance (Mo) X-ray Source1798 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.016
Detector resolution: 8.4 pixels mm-1θmax = 25.0°, θmin = 2.9°
ω scansh = 1413
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2009)
k = 910
Tmin = 0.968, Tmax = 1.000l = 1313
13393 measured 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)] = 0.025Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.068H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0355P)2 + 0.4207P]
where P = (Fo2 + 2Fc2)/3
2022 reflections(Δ/σ)max < 0.001
149 parametersΔρmax = 0.21 e Å3
0 restraintsΔρmin = 0.18 e Å3
Crystal data top
C10H14ClN5V = 1147.30 (5) Å3
Mr = 239.71Z = 4
Monoclinic, P21/cMo Kα radiation
a = 12.0483 (3) ŵ = 0.31 mm1
b = 8.7689 (2) ÅT = 120 K
c = 11.5538 (3) Å0.40 × 0.40 × 0.30 mm
β = 109.965 (3)°
Data collection top
Oxford Diffraction Xcalibur (Sapphire2 large Be window)
diffractometer
2022 independent reflections
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2009)
1798 reflections with I > 2σ(I)
Tmin = 0.968, Tmax = 1.000Rint = 0.016
13393 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0250 restraints
wR(F2) = 0.068H-atom parameters constrained
S = 1.05Δρmax = 0.21 e Å3
2022 reflectionsΔρmin = 0.18 e Å3
149 parameters
Special details top

Experimental. CrysAlis RED (Oxford Diffraction Ltd, 2009). Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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
xyzUiso*/Ueq
Cl10.78721 (3)0.18146 (4)0.33908 (3)0.02432 (12)
N10.80758 (9)0.04481 (12)0.48883 (9)0.0166 (2)
N20.67313 (9)0.15775 (12)0.49228 (10)0.0179 (3)
N30.69089 (10)0.14494 (13)0.72589 (10)0.0225 (3)
N40.82037 (10)0.23853 (13)0.64258 (10)0.0184 (3)
N50.55582 (10)0.16106 (13)0.61327 (10)0.0197 (3)
C10.75175 (11)0.08580 (15)0.45552 (11)0.0168 (3)
C20.63956 (11)0.09009 (15)0.58130 (11)0.0169 (3)
C30.69562 (11)0.04950 (15)0.63134 (11)0.0167 (3)
C40.76612 (12)0.25408 (16)0.72857 (13)0.0229 (3)
H4A0.78160.33660.78510.027*
C50.77572 (11)0.10713 (15)0.57988 (11)0.0157 (3)
C60.51096 (13)0.30962 (16)0.56040 (14)0.0256 (3)
H6A0.49330.30680.47110.038*
H6B0.57070.38800.59680.038*
H6C0.43880.33370.57780.038*
C70.51768 (12)0.10497 (17)0.71274 (13)0.0248 (3)
H7A0.51910.00680.71340.037*
H7B0.43720.14060.69980.037*
H7C0.57110.14350.79170.037*
C80.90697 (12)0.34193 (16)0.61883 (13)0.0214 (3)
H8A0.94680.28490.56910.026*
C90.84438 (14)0.47859 (18)0.54375 (14)0.0314 (4)
H9A0.78660.44330.46600.047*
H9B0.80380.53580.59040.047*
H9C0.90240.54470.52650.047*
C101.00104 (13)0.38877 (18)0.73954 (14)0.0294 (3)
H10A1.03590.29740.78680.044*
H10B1.06270.44760.72210.044*
H10C0.96500.45150.78740.044*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0311 (2)0.0225 (2)0.02385 (19)0.00422 (14)0.01520 (15)0.00769 (13)
N10.0180 (5)0.0170 (6)0.0149 (5)0.0002 (4)0.0058 (4)0.0005 (4)
N20.0189 (6)0.0173 (6)0.0176 (5)0.0002 (4)0.0062 (4)0.0005 (4)
N30.0256 (6)0.0227 (6)0.0219 (6)0.0007 (5)0.0115 (5)0.0038 (5)
N40.0198 (6)0.0168 (6)0.0189 (6)0.0020 (4)0.0071 (5)0.0037 (5)
N50.0196 (6)0.0200 (6)0.0204 (6)0.0021 (5)0.0081 (5)0.0020 (5)
C10.0192 (7)0.0170 (7)0.0136 (6)0.0023 (5)0.0046 (5)0.0003 (5)
C20.0162 (6)0.0174 (7)0.0152 (6)0.0031 (5)0.0031 (5)0.0048 (5)
C30.0169 (6)0.0174 (7)0.0155 (6)0.0025 (5)0.0049 (5)0.0019 (5)
C40.0267 (7)0.0221 (8)0.0219 (7)0.0014 (6)0.0109 (6)0.0067 (6)
C50.0149 (6)0.0153 (7)0.0149 (6)0.0017 (5)0.0025 (5)0.0016 (5)
C60.0264 (7)0.0228 (8)0.0280 (8)0.0070 (6)0.0097 (6)0.0013 (6)
C70.0231 (7)0.0284 (8)0.0276 (7)0.0006 (6)0.0148 (6)0.0038 (6)
C80.0202 (7)0.0212 (7)0.0250 (7)0.0051 (6)0.0105 (6)0.0055 (6)
C90.0347 (9)0.0262 (8)0.0329 (8)0.0061 (7)0.0110 (7)0.0036 (7)
C100.0225 (7)0.0306 (8)0.0326 (8)0.0044 (6)0.0064 (6)0.0094 (7)
Geometric parameters (Å, º) top
Cl1—C11.7575 (13)C6—H6A0.9800
N1—C11.3174 (17)C6—H6B0.9800
N1—C51.3522 (17)C6—H6C0.9800
N2—C11.3230 (17)C7—H7A0.9800
N2—C21.3630 (17)C7—H7B0.9800
N3—C41.3112 (18)C7—H7C0.9800
N3—C31.3926 (17)C8—C91.520 (2)
N4—C51.3696 (17)C8—C101.5228 (19)
N4—C41.3698 (18)C8—H8A1.0000
N4—C81.4769 (17)C9—H9A0.9800
N5—C21.3402 (17)C9—H9B0.9800
N5—C71.4610 (18)C9—H9C0.9800
N5—C61.4618 (18)C10—H10A0.9800
C2—C31.4220 (19)C10—H10B0.9800
C3—C51.3900 (18)C10—H10C0.9800
C4—H4A0.9500
C1—N1—C5109.04 (11)N5—C6—H6C109.5
C1—N2—C2117.66 (11)H6A—C6—H6C109.5
C4—N3—C3104.13 (11)H6B—C6—H6C109.5
C5—N4—C4105.59 (11)N5—C7—H7A109.5
C5—N4—C8126.37 (11)N5—C7—H7B109.5
C4—N4—C8128.02 (11)H7A—C7—H7B109.5
C2—N5—C7121.94 (11)N5—C7—H7C109.5
C2—N5—C6120.29 (11)H7A—C7—H7C109.5
C7—N5—C6117.26 (11)H7B—C7—H7C109.5
N1—C1—N2132.14 (12)N4—C8—C9110.23 (11)
N1—C1—Cl1113.90 (10)N4—C8—C10110.34 (11)
N2—C1—Cl1113.95 (10)C9—C8—C10112.28 (12)
N5—C2—N2116.82 (12)N4—C8—H8A107.9
N5—C2—C3125.83 (12)C9—C8—H8A107.9
N2—C2—C3117.35 (11)C10—C8—H8A107.9
C5—C3—N3109.72 (11)C8—C9—H9A109.5
C5—C3—C2116.22 (12)C8—C9—H9B109.5
N3—C3—C2134.05 (12)H9A—C9—H9B109.5
N3—C4—N4114.04 (12)C8—C9—H9C109.5
N3—C4—H4A123.0H9A—C9—H9C109.5
N4—C4—H4A123.0H9B—C9—H9C109.5
N1—C5—N4125.94 (12)C8—C10—H10A109.5
N1—C5—C3127.51 (12)C8—C10—H10B109.5
N4—C5—C3106.52 (11)H10A—C10—H10B109.5
N5—C6—H6A109.5C8—C10—H10C109.5
N5—C6—H6B109.5H10A—C10—H10C109.5
H6A—C6—H6B109.5H10B—C10—H10C109.5
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C4—H4A···N1i0.952.493.3728 (18)154
C7—H7C···Cl1ii0.982.913.5981 (14)128
C7—H7B···N3iii0.982.753.584 (2)143
C9—H9A···N3iv0.982.733.6664 (18)161
Symmetry codes: (i) x, y1/2, z+1/2; (ii) x, y+1/2, z+1/2; (iii) x+1, y+1/2, z+3/2; (iv) x, y1/2, z1/2.

Experimental details

Crystal data
Chemical formulaC10H14ClN5
Mr239.71
Crystal system, space groupMonoclinic, P21/c
Temperature (K)120
a, b, c (Å)12.0483 (3), 8.7689 (2), 11.5538 (3)
β (°) 109.965 (3)
V3)1147.30 (5)
Z4
Radiation typeMo Kα
µ (mm1)0.31
Crystal size (mm)0.40 × 0.40 × 0.30
Data collection
DiffractometerOxford Diffraction Xcalibur (Sapphire2 large Be window)
Absorption correctionMulti-scan
(CrysAlis RED; Oxford Diffraction, 2009)
Tmin, Tmax0.968, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
13393, 2022, 1798
Rint0.016
(sin θ/λ)max1)0.594
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.025, 0.068, 1.05
No. of reflections2022
No. of parameters149
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.21, 0.18

Computer programs: CrysAlis CCD (Oxford Diffraction, 2009), CrysAlis RED (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), 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
C4—H4A···N1i0.952.493.3728 (18)154.0
C7—H7C···Cl1ii0.982.913.5981 (14)128.2
C7—H7B···N3iii0.982.753.584 (2)143.3
C9—H9A···N3iv0.982.733.6664 (18)160.6
Symmetry codes: (i) x, y1/2, z+1/2; (ii) x, y+1/2, z+1/2; (iii) x+1, y+1/2, z+3/2; (iv) x, y1/2, z1/2.
 

Acknowledgements

The financial support of this work by the Czech Ministry of Education, project No. MSM 7088352101 is gratefully acknowledged.

References

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