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

Rouchal, M.; Nečas, M.; Vícha, R.

doi:10.1107/S1600536810011797

organic compounds

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ISSN: 2056-9890

Volume 66| Part 5| May 2010| Page o1016

https://doi.org/10.1107/S1600536810011797

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

Michal Rouchal,^a Marek Nečas ^b and Robert Vícha ^a ^*

^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 ). 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

Crystal data

C₁₀H₁₄ClN₅
M_r = 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 $[Oxford Diffraction (2009). CrysAlis RED and CrysAlis CCD. Oxford Diffraction Ltd, Yarnton, England.]$ ) T_min = 0.968, T_max = 1.000
13393 measured reflections
2022 independent reflections
1798 reflections with I > 2σ(I)
R_int = 0.016

Refinement

R[F² > 2σ(F²)] = 0.025
wR(F²) = 0.068
S = 1.05
2022 reflections
149 parameters
H-atom parameters constrained
Δρ_max = 0.21 e Å⁻³
Δρ_min = −0.18 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	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⋯N3^iv	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 ); 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.

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536810011797/pk2238sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810011797/pk2238Isup2.hkl

checkCIF report

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 19^th 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

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

	Fig. 1. An ellipsoid plot (50% probability) of the asymmetric unit. Hydrogen atoms are represented as arbitrary spheres.
	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

C₁₀H₁₄ClN₅	F(000) = 504
M_r = 239.71	D_x = 1.388 Mg m⁻³
Monoclinic, P2₁/c	Melting point = 422–418 K
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.7107 Å
a = 12.0483 (3) Å	Cell parameters from 8720 reflections
b = 8.7689 (2) Å	θ = 2.9–27.3°
c = 11.5538 (3) Å	µ = 0.31 mm⁻¹
β = 109.965 (3)°	T = 120 K
V = 1147.30 (5) Å³	Block, colourless
Z = 4	0.40 × 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 Source	1798 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.016
Detector resolution: 8.4 pixels mm^-1	θ_max = 25.0°, θ_min = 2.9°
ω scans	h = −14→13
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009)	k = −9→10
T_min = 0.968, T_max = 1.000	l = −13→13
13393 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)] = 0.025	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.068	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.0355P)² + 0.4207P] where P = (F_o² + 2F_c²)/3
2022 reflections	(Δ/σ)_max < 0.001
149 parameters	Δρ_max = 0.21 e Å⁻³
0 restraints	Δρ_min = −0.18 e Å⁻³

Crystal data top

C₁₀H₁₄ClN₅	V = 1147.30 (5) Å³
M_r = 239.71	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 12.0483 (3) Å	µ = 0.31 mm⁻¹
b = 8.7689 (2) Å	T = 120 K
c = 11.5538 (3) Å	0.40 × 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)
T_min = 0.968, T_max = 1.000	R_int = 0.016
13393 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.025	0 restraints
wR(F²) = 0.068	H-atom parameters constrained
S = 1.05	Δρ_max = 0.21 e Å⁻³
2022 reflections	Δρ_min = −0.18 e Å⁻³
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

	x	y	z	U_iso*/U_eq
Cl1	0.78721 (3)	0.18146 (4)	0.33908 (3)	0.02432 (12)
N1	0.80758 (9)	−0.04481 (12)	0.48883 (9)	0.0166 (2)
N2	0.67313 (9)	0.15775 (12)	0.49228 (10)	0.0179 (3)
N3	0.69089 (10)	−0.14494 (13)	0.72589 (10)	0.0225 (3)
N4	0.82037 (10)	−0.23853 (13)	0.64258 (10)	0.0184 (3)
N5	0.55582 (10)	0.16106 (13)	0.61327 (10)	0.0197 (3)
C1	0.75175 (11)	0.08580 (15)	0.45552 (11)	0.0168 (3)
C2	0.63956 (11)	0.09009 (15)	0.58130 (11)	0.0169 (3)
C3	0.69562 (11)	−0.04950 (15)	0.63134 (11)	0.0167 (3)
C4	0.76612 (12)	−0.25408 (16)	0.72857 (13)	0.0229 (3)
H4A	0.7816	−0.3366	0.7851	0.027*
C5	0.77572 (11)	−0.10713 (15)	0.57988 (11)	0.0157 (3)
C6	0.51096 (13)	0.30962 (16)	0.56040 (14)	0.0256 (3)
H6A	0.4933	0.3068	0.4711	0.038*
H6B	0.5707	0.3880	0.5968	0.038*
H6C	0.4388	0.3337	0.5778	0.038*
C7	0.51768 (12)	0.10497 (17)	0.71274 (13)	0.0248 (3)
H7A	0.5191	−0.0068	0.7134	0.037*
H7B	0.4372	0.1406	0.6998	0.037*
H7C	0.5711	0.1435	0.7917	0.037*
C8	0.90697 (12)	−0.34193 (16)	0.61883 (13)	0.0214 (3)
H8A	0.9468	−0.2849	0.5691	0.026*
C9	0.84438 (14)	−0.47859 (18)	0.54375 (14)	0.0314 (4)
H9A	0.7866	−0.4433	0.4660	0.047*
H9B	0.8038	−0.5358	0.5904	0.047*
H9C	0.9024	−0.5447	0.5265	0.047*
C10	1.00104 (13)	−0.38877 (18)	0.73954 (14)	0.0294 (3)
H10A	1.0359	−0.2974	0.7868	0.044*
H10B	1.0627	−0.4476	0.7221	0.044*
H10C	0.9650	−0.4515	0.7874	0.044*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0311 (2)	0.0225 (2)	0.02385 (19)	0.00422 (14)	0.01520 (15)	0.00769 (13)
N1	0.0180 (5)	0.0170 (6)	0.0149 (5)	−0.0002 (4)	0.0058 (4)	0.0005 (4)
N2	0.0189 (6)	0.0173 (6)	0.0176 (5)	0.0002 (4)	0.0062 (4)	−0.0005 (4)
N3	0.0256 (6)	0.0227 (6)	0.0219 (6)	0.0007 (5)	0.0115 (5)	0.0038 (5)
N4	0.0198 (6)	0.0168 (6)	0.0189 (6)	0.0020 (4)	0.0071 (5)	0.0037 (5)
N5	0.0196 (6)	0.0200 (6)	0.0204 (6)	0.0021 (5)	0.0081 (5)	−0.0020 (5)
C1	0.0192 (7)	0.0170 (7)	0.0136 (6)	−0.0023 (5)	0.0046 (5)	−0.0003 (5)
C2	0.0162 (6)	0.0174 (7)	0.0152 (6)	−0.0031 (5)	0.0031 (5)	−0.0048 (5)
C3	0.0169 (6)	0.0174 (7)	0.0155 (6)	−0.0025 (5)	0.0049 (5)	−0.0019 (5)
C4	0.0267 (7)	0.0221 (8)	0.0219 (7)	0.0014 (6)	0.0109 (6)	0.0067 (6)
C5	0.0149 (6)	0.0153 (7)	0.0149 (6)	−0.0017 (5)	0.0025 (5)	−0.0016 (5)
C6	0.0264 (7)	0.0228 (8)	0.0280 (8)	0.0070 (6)	0.0097 (6)	−0.0013 (6)
C7	0.0231 (7)	0.0284 (8)	0.0276 (7)	−0.0006 (6)	0.0148 (6)	−0.0038 (6)
C8	0.0202 (7)	0.0212 (7)	0.0250 (7)	0.0051 (6)	0.0105 (6)	0.0055 (6)
C9	0.0347 (9)	0.0262 (8)	0.0329 (8)	0.0061 (7)	0.0110 (7)	−0.0036 (7)
C10	0.0225 (7)	0.0306 (8)	0.0326 (8)	0.0044 (6)	0.0064 (6)	0.0094 (7)

Geometric parameters (Å, º) top

Cl1—C1	1.7575 (13)	C6—H6A	0.9800
N1—C1	1.3174 (17)	C6—H6B	0.9800
N1—C5	1.3522 (17)	C6—H6C	0.9800
N2—C1	1.3230 (17)	C7—H7A	0.9800
N2—C2	1.3630 (17)	C7—H7B	0.9800
N3—C4	1.3112 (18)	C7—H7C	0.9800
N3—C3	1.3926 (17)	C8—C9	1.520 (2)
N4—C5	1.3696 (17)	C8—C10	1.5228 (19)
N4—C4	1.3698 (18)	C8—H8A	1.0000
N4—C8	1.4769 (17)	C9—H9A	0.9800
N5—C2	1.3402 (17)	C9—H9B	0.9800
N5—C7	1.4610 (18)	C9—H9C	0.9800
N5—C6	1.4618 (18)	C10—H10A	0.9800
C2—C3	1.4220 (19)	C10—H10B	0.9800
C3—C5	1.3900 (18)	C10—H10C	0.9800
C4—H4A	0.9500

C1—N1—C5	109.04 (11)	N5—C6—H6C	109.5
C1—N2—C2	117.66 (11)	H6A—C6—H6C	109.5
C4—N3—C3	104.13 (11)	H6B—C6—H6C	109.5
C5—N4—C4	105.59 (11)	N5—C7—H7A	109.5
C5—N4—C8	126.37 (11)	N5—C7—H7B	109.5
C4—N4—C8	128.02 (11)	H7A—C7—H7B	109.5
C2—N5—C7	121.94 (11)	N5—C7—H7C	109.5
C2—N5—C6	120.29 (11)	H7A—C7—H7C	109.5
C7—N5—C6	117.26 (11)	H7B—C7—H7C	109.5
N1—C1—N2	132.14 (12)	N4—C8—C9	110.23 (11)
N1—C1—Cl1	113.90 (10)	N4—C8—C10	110.34 (11)
N2—C1—Cl1	113.95 (10)	C9—C8—C10	112.28 (12)
N5—C2—N2	116.82 (12)	N4—C8—H8A	107.9
N5—C2—C3	125.83 (12)	C9—C8—H8A	107.9
N2—C2—C3	117.35 (11)	C10—C8—H8A	107.9
C5—C3—N3	109.72 (11)	C8—C9—H9A	109.5
C5—C3—C2	116.22 (12)	C8—C9—H9B	109.5
N3—C3—C2	134.05 (12)	H9A—C9—H9B	109.5
N3—C4—N4	114.04 (12)	C8—C9—H9C	109.5
N3—C4—H4A	123.0	H9A—C9—H9C	109.5
N4—C4—H4A	123.0	H9B—C9—H9C	109.5
N1—C5—N4	125.94 (12)	C8—C10—H10A	109.5
N1—C5—C3	127.51 (12)	C8—C10—H10B	109.5
N4—C5—C3	106.52 (11)	H10A—C10—H10B	109.5
N5—C6—H6A	109.5	C8—C10—H10C	109.5
N5—C6—H6B	109.5	H10A—C10—H10C	109.5
H6A—C6—H6B	109.5	H10B—C10—H10C	109.5

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	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···N3^iv	0.98	2.73	3.6664 (18)	161

Symmetry codes: (i) x, −y−1/2, z+1/2; (ii) x, −y+1/2, z+1/2; (iii) −x+1, y+1/2, −z+3/2; (iv) x, −y−1/2, z−1/2.

Experimental details

Crystal data
Chemical formula	C₁₀H₁₄ClN₅
M_r	239.71
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	120
a, b, c (Å)	12.0483 (3), 8.7689 (2), 11.5538 (3)
β (°)	109.965 (3)
V (Å³)	1147.30 (5)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.31
Crystal size (mm)	0.40 × 0.40 × 0.30

Data collection
Diffractometer	Oxford Diffraction Xcalibur (Sapphire2 large Be window)
Absorption correction	Multi-scan (CrysAlis RED; Oxford Diffraction, 2009)
T_min, T_max	0.968, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	13393, 2022, 1798
R_int	0.016
(sin θ/λ)_max (Å⁻¹)	0.594

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.025, 0.068, 1.05
No. of reflections	2022
No. of parameters	149
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	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···A	D—H	H···A	D···A	D—H···A
C4—H4A···N1ⁱ	0.95	2.49	3.3728 (18)	154.0
C7—H7C···Cl1ⁱⁱ	0.98	2.91	3.5981 (14)	128.2
C7—H7B···N3ⁱⁱⁱ	0.98	2.75	3.584 (2)	143.3
C9—H9A···N3^iv	0.98	2.73	3.6664 (18)	160.6

Symmetry codes: (i) x, −y−1/2, z+1/2; (ii) x, −y+1/2, z+1/2; (iii) −x+1, y+1/2, −z+3/2; (iv) x, −y−1/2, z−1/2.

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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