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ISSN: 2056-9890

6-Amino-2-methyl-8-phenyl-1,2,3,4-tetra­hydro­iso­quinoline-5,7-dicarbo­nitrile

aDepartment of Pharmaceutical and Biological Engineering, College of Chemical Engineering, Sichuan University, Chengdu 610065, People's Republic of China
*Correspondence e-mail: cusack@scu.edu.cn

(Received 19 April 2013; accepted 15 May 2013; online 22 May 2013)

In the title compound, C18H16N4, the dihedral angle between the benzene and phenyl rings is 61.40 (4)°. In the crystal, mol­ecules are linked by N—H⋯N(nitrile) hydrogen bonds, forming inversion dimers. The dimers are further linked by N—H⋯N(amine) hydrogen bonds, and both units are arranged almost perpendicular to each other [angle between dimer mean planes = 84.43 (12)°]. This arrangement is extended to form a ladder-like structure parallel to the c axis.

Related literature

For background to natural products containing an iso­quinoline backbone, see: Marchand et al. (2006[Marchand, C., Antony, S., Kohn, K. W., Cushman, M., Ioanoviciu, A., Staker, B. L., Burgin, A. B., Stewart, L. & Pommier, Y. (2006). Mol. Cancer Ther. 5, 287-295.]); Cho et al. (2007[Cho, W.-J., Le, Q. M., Van, H. T. M., Lee, K. Y., Kang, B. Y., Lee, E.-S., Lee, S. K. & Kwon, Y. (2007). Bioorg. Med. Chem. Lett. 17, 3531-3534.]); Van Quaquebeke et al. (2007[Van Quaquebeke, E., Mahieu, T., Dumont, P., Dewelle, J., Ribaucour, F., Simon, G., Sauvage, S., Gaussin, J.-F., Tuti, J., El Yazidi, M., Van Vynckt, F., Mijatovic, T., Lefranc, F., Darro, F. & Kiss, R. (2007). J. Med. Chem. 50, 4122-4134.]). For related structures, see: Rong et al. (2010[Rong, L. C., Gao, L. J., Han, H. X., Jiang, H., Dai, Y. S. & Tu, S. J. (2010). Synth. Commun. 40, 289-294.]); Balamurugan et al. (2011[Balamurugan, K., Jeyachandran, V., Perumal, S. & Menéndez, J. C. (2011). Tetrahedron, 67, 1432-1437.]).

[Scheme 1]

Experimental

Crystal data
  • C18H16N4

  • Mr = 288.35

  • Monoclinic, P 21 /c

  • a = 17.5630 (5) Å

  • b = 6.25208 (19) Å

  • c = 13.7963 (4) Å

  • β = 93.209 (3)°

  • V = 1512.53 (8) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 143 K

  • 0.38 × 0.35 × 0.25 mm

Data collection
  • Agilent Xcalibur Eos diffractometer

  • Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis PRO. Oxford Diffraction, Yarnton, England.]) Tmin = 0.960, Tmax = 1.000

  • 6799 measured reflections

  • 3089 independent reflections

  • 2414 reflections with I > 2σ(I)

  • Rint = 0.034

Refinement
  • R[F2 > 2σ(F2)] = 0.045

  • wR(F2) = 0.112

  • S = 1.05

  • 3089 reflections

  • 206 parameters

  • 4 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.19 e Å−3

  • Δρmin = −0.22 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N4—H4A⋯N2i 0.89 (1) 2.21 (1) 3.052 (2) 157 (2)
N4—H4B⋯N1ii 0.87 (1) 2.21 (1) 3.0261 (19) 155 (2)
Symmetry codes: (i) -x+1, -y+1, -z+1; (ii) [x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}].

Data collection: CrysAlis PRO (Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis PRO. Oxford Diffraction, Yarnton, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; 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: OLEX2 (Dolomanov et al., 2009[Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2009). J. Appl. Cryst. 42, 339-341.]) 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: OLEX2.

Supporting information


Comment top

Various natural products containing an isoquinoline backbone have received considerable attention over the past years, because of their different kinds of bioactivities (Marchand et al., 2006; Cho et al., 2007; Van Quaquebeke et al., 2007). The development of efficient synthetic methods for isoquinoline and related derivatives is continuously attracting the attention of many chemists (Rong et al., 2010; Balamurugan et al., 2011). As a part of our current studies on the development of new routes in organic synthesis and the screen of anticancer drugs, in this article, we report the crystal structure of the title compound (Fig. 1).

The dihedral angle between the benzene and the phenyl rings is 61.40 (4)°. In the crystal (Fig. 2), two kinds of hydrogen bonds are formed, i.e., NH···N(nitrile group) and NH···N(amine) hydrogen bonds, connecting molecules in different directions. The NH···N(nitrile group) hydrogen bonds are involved in the formation of centrosymmetric dimers, and this basic unit is linked by NH···N(amine) hydrogen bonds to four other symmetry-related units, which are parallel to each other. Non-parallel units are arranged almost perpendicular to each other [angle between unit mean planes: 84.43 (12)°] forming a ladder structure, that can extend into infinite sheets through the vertical direction of the step cross section. On the step cross section, the distance between the centers of two units is 6.252 (13) Å.

Related literature top

For background to natural products containing an isoquinoline backbone, see: Marchand et al. (2006); Cho et al. (2007); Van Quaquebeke et al. (2007). For related structures, see: Rong et al. (2010); Balamurugan et al. (2011).

Experimental top

Benzaldehyde (1 mmol) was added to a stirred solution of 1-methyl-4-piperidone (1 mmol) and tetrahydro pyrrole (1.2 mmol) in dichloromethane. The resulting mixture was refluxed for 4 h to obtain a α,β-unsaturated ketone as an intermediate. Subsequently, this α,β-unsaturated ketone (1 mmol) was reacted with malononitrile (2 mmol) under strong basic conditions (Rong et al., 2009), monitoring the reaction progress by TLC. After the completion of the reaction, the solvent was evaporated under reduce pressure and the crude product was purified by silica gel column chromatography. Crystals suitable for X-ray analysis were obtained by slow evaporation of a solution in methanol and dichloromethane (4:1).

Refinement top

Carbon-bound H-atoms were placed in calculated positions [C—H = 0.95–0.99 Å, Uiso(H) = 1.2–1.5Ueq(parent atom)] and were allowed to ride on their parent atoms. The amino-H atoms H4A and H4B were located in a difference map, and subsequently refined freely, with Uiso(H) = 1.2Ueq(N4).

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: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009) and Mercury (Macrae et al., 2008); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, with displacement ellipsoids drawn at the 30% probability level.
[Figure 2] Fig. 2. The crystal packing of the title compound. H atoms not involved in hydrogen bonding are omitted for clarity.
6-Amino-2-methyl-8-phenyl-1,2,3,4-tetrahydroisoquinoline-5,7-dicarbonitrile top
Crystal data top
C18H16N4F(000) = 608
Mr = 288.35Dx = 1.266 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.7107 Å
a = 17.5630 (5) ÅCell parameters from 2345 reflections
b = 6.25208 (19) Åθ = 3.0–29.0°
c = 13.7963 (4) ŵ = 0.08 mm1
β = 93.209 (3)°T = 143 K
V = 1512.53 (8) Å3Block, colourless
Z = 40.38 × 0.35 × 0.25 mm
Data collection top
Agilent Xcalibur Eos
diffractometer
3089 independent reflections
Radiation source: Enhance (Mo) X-ray Source2414 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.034
Detector resolution: 16.0874 pixels mm-1θmax = 26.4°, θmin = 3.0°
ω scansh = 2121
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2009)
k = 77
Tmin = 0.960, Tmax = 1.000l = 1617
6799 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)] = 0.045Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.112H atoms treated by a mixture of independent and constrained refinement
S = 1.05 w = 1/[σ2(Fo2) + (0.0403P)2 + 0.3434P]
where P = (Fo2 + 2Fc2)/3
3089 reflections(Δ/σ)max < 0.001
206 parametersΔρmax = 0.19 e Å3
4 restraintsΔρmin = 0.22 e Å3
0 constraints
Crystal data top
C18H16N4V = 1512.53 (8) Å3
Mr = 288.35Z = 4
Monoclinic, P21/cMo Kα radiation
a = 17.5630 (5) ŵ = 0.08 mm1
b = 6.25208 (19) ÅT = 143 K
c = 13.7963 (4) Å0.38 × 0.35 × 0.25 mm
β = 93.209 (3)°
Data collection top
Agilent Xcalibur Eos
diffractometer
3089 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2009)
2414 reflections with I > 2σ(I)
Tmin = 0.960, Tmax = 1.000Rint = 0.034
6799 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0454 restraints
wR(F2) = 0.112H atoms treated by a mixture of independent and constrained refinement
S = 1.05Δρmax = 0.19 e Å3
3089 reflectionsΔρmin = 0.22 e Å3
206 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
N10.29081 (7)0.2394 (2)0.20203 (9)0.0244 (3)
N20.50947 (9)0.2855 (3)0.43619 (13)0.0498 (5)
N30.14961 (8)0.4536 (2)0.57681 (10)0.0308 (3)
N40.34160 (8)0.4642 (2)0.53715 (11)0.0323 (4)
H4A0.3908 (8)0.501 (3)0.5410 (12)0.039*
H4B0.3136 (9)0.524 (3)0.5798 (11)0.039*
C10.36603 (8)0.1934 (2)0.41825 (11)0.0234 (3)
C20.31623 (9)0.3112 (2)0.47415 (11)0.0223 (3)
C30.23791 (8)0.2589 (2)0.46164 (10)0.0201 (3)
C40.21118 (8)0.0990 (2)0.39679 (10)0.0199 (3)
C50.26291 (8)0.0177 (2)0.34345 (10)0.0207 (3)
C60.34051 (8)0.0294 (2)0.35473 (10)0.0221 (3)
C70.39820 (9)0.0919 (3)0.29916 (12)0.0288 (4)
H7A0.44170.13300.34400.035*
H7B0.41790.00240.24860.035*
C80.36428 (9)0.2911 (3)0.25165 (12)0.0274 (4)
H8A0.39940.34830.20430.033*
H8B0.35720.40210.30150.033*
C90.23529 (9)0.1913 (2)0.27405 (11)0.0238 (4)
H9A0.22510.32270.31130.029*
H9B0.18680.14570.24030.029*
C100.12744 (8)0.0567 (2)0.38652 (10)0.0205 (3)
C110.07739 (9)0.2175 (3)0.35361 (11)0.0251 (4)
H110.09670.35410.33740.030*
C120.00049 (9)0.1790 (3)0.34448 (11)0.0300 (4)
H120.03430.28890.32170.036*
C130.02895 (9)0.0187 (3)0.36837 (11)0.0306 (4)
H130.08230.04460.36230.037*
C140.02015 (9)0.1791 (3)0.40108 (11)0.0292 (4)
H140.00050.31520.41740.035*
C150.09809 (9)0.1418 (2)0.41021 (11)0.0243 (4)
H150.13160.25260.43280.029*
C160.44596 (9)0.2426 (3)0.42808 (12)0.0311 (4)
C170.18663 (8)0.3655 (2)0.52358 (11)0.0221 (3)
C180.26348 (10)0.4182 (3)0.14143 (12)0.0344 (4)
H18A0.25950.54640.18170.052*
H18B0.29930.44470.09090.052*
H18C0.21320.38330.11110.052*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0234 (7)0.0257 (7)0.0243 (7)0.0017 (6)0.0042 (5)0.0057 (5)
N20.0229 (8)0.0629 (11)0.0644 (11)0.0121 (8)0.0114 (7)0.0318 (9)
N30.0234 (7)0.0328 (8)0.0363 (8)0.0017 (6)0.0042 (6)0.0068 (6)
N40.0208 (7)0.0385 (8)0.0383 (8)0.0093 (7)0.0084 (6)0.0166 (7)
C10.0173 (8)0.0276 (8)0.0255 (8)0.0043 (6)0.0033 (6)0.0005 (7)
C20.0215 (8)0.0235 (8)0.0222 (8)0.0039 (6)0.0021 (6)0.0006 (6)
C30.0191 (8)0.0206 (8)0.0207 (7)0.0003 (6)0.0029 (6)0.0023 (6)
C40.0185 (7)0.0207 (8)0.0204 (7)0.0016 (6)0.0008 (6)0.0056 (6)
C50.0198 (8)0.0219 (8)0.0205 (7)0.0014 (6)0.0018 (6)0.0025 (6)
C60.0202 (8)0.0246 (8)0.0217 (7)0.0009 (6)0.0033 (6)0.0008 (6)
C70.0206 (8)0.0365 (9)0.0298 (9)0.0008 (7)0.0044 (6)0.0061 (7)
C80.0242 (9)0.0277 (9)0.0306 (9)0.0022 (7)0.0046 (7)0.0037 (7)
C90.0214 (8)0.0255 (8)0.0248 (8)0.0027 (6)0.0034 (6)0.0015 (6)
C100.0186 (8)0.0250 (8)0.0180 (7)0.0007 (6)0.0021 (6)0.0029 (6)
C110.0228 (8)0.0285 (9)0.0239 (8)0.0003 (7)0.0009 (6)0.0007 (7)
C120.0203 (8)0.0426 (10)0.0271 (9)0.0060 (7)0.0002 (6)0.0023 (7)
C130.0160 (8)0.0494 (11)0.0265 (8)0.0053 (7)0.0036 (6)0.0102 (8)
C140.0267 (9)0.0336 (9)0.0281 (9)0.0095 (7)0.0080 (7)0.0065 (7)
C150.0228 (8)0.0256 (8)0.0246 (8)0.0022 (7)0.0039 (6)0.0009 (7)
C160.0234 (9)0.0353 (9)0.0353 (9)0.0050 (7)0.0071 (7)0.0142 (8)
C170.0189 (8)0.0210 (8)0.0260 (8)0.0042 (6)0.0011 (6)0.0005 (7)
C180.0331 (10)0.0334 (10)0.0369 (10)0.0041 (8)0.0037 (7)0.0119 (8)
Geometric parameters (Å, º) top
N1—C81.463 (2)C7—H7B0.9900
N1—C91.4618 (19)C7—C81.514 (2)
N1—C181.4607 (19)C8—H8A0.9900
N2—C161.147 (2)C8—H8B0.9900
N3—C171.1483 (19)C9—H9A0.9900
N4—H4A0.893 (12)C9—H9B0.9900
N4—H4B0.874 (12)C10—C111.394 (2)
N4—C21.3510 (19)C10—C151.390 (2)
C1—C21.406 (2)C11—H110.9500
C1—C61.406 (2)C11—C121.388 (2)
C1—C161.436 (2)C12—H120.9500
C2—C31.415 (2)C12—C131.380 (2)
C3—C41.405 (2)C13—H130.9500
C3—C171.439 (2)C13—C141.381 (2)
C4—C51.405 (2)C14—H140.9500
C4—C101.4931 (19)C14—C151.387 (2)
C5—C61.394 (2)C15—H150.9500
C5—C91.510 (2)C18—H18A0.9800
C6—C71.509 (2)C18—H18B0.9800
C7—H7A0.9900C18—H18C0.9800
C9—N1—C8109.38 (12)C7—C8—H8B109.7
C18—N1—C8110.60 (12)H8A—C8—H8B108.2
C18—N1—C9109.63 (12)N1—C9—C5112.08 (12)
H4A—N4—H4B115.4 (16)N1—C9—H9A109.2
C2—N4—H4A120.3 (11)N1—C9—H9B109.2
C2—N4—H4B124.1 (11)C5—C9—H9A109.2
C2—C1—C16118.09 (14)C5—C9—H9B109.2
C6—C1—C2122.51 (14)H9A—C9—H9B107.9
C6—C1—C16119.40 (14)C11—C10—C4120.20 (13)
N4—C2—C1122.05 (14)C15—C10—C4120.79 (13)
N4—C2—C3121.70 (14)C15—C10—C11119.01 (14)
C1—C2—C3116.25 (13)C10—C11—H11119.9
C2—C3—C17117.18 (13)C12—C11—C10120.30 (15)
C4—C3—C2122.01 (13)C12—C11—H11119.9
C4—C3—C17120.65 (13)C11—C12—H12119.9
C3—C4—C5120.01 (13)C13—C12—C11120.15 (15)
C3—C4—C10118.59 (13)C13—C12—H12119.9
C5—C4—C10121.39 (13)C12—C13—H13120.0
C4—C5—C9120.75 (13)C12—C13—C14120.00 (15)
C6—C5—C4119.25 (13)C14—C13—H13120.0
C6—C5—C9120.00 (13)C13—C14—H14119.9
C1—C6—C7118.93 (13)C13—C14—C15120.17 (15)
C5—C6—C1119.93 (13)C15—C14—H14119.9
C5—C6—C7121.13 (13)C10—C15—H15119.8
C6—C7—H7A109.2C14—C15—C10120.37 (15)
C6—C7—H7B109.2C14—C15—H15119.8
C6—C7—C8111.98 (13)N2—C16—C1178.82 (19)
H7A—C7—H7B107.9N3—C17—C3175.71 (15)
C8—C7—H7A109.2N1—C18—H18A109.5
C8—C7—H7B109.2N1—C18—H18B109.5
N1—C8—C7109.66 (13)N1—C18—H18C109.5
N1—C8—H8A109.7H18A—C18—H18B109.5
N1—C8—H8B109.7H18A—C18—H18C109.5
C7—C8—H8A109.7H18B—C18—H18C109.5
N4—C2—C3—C4179.53 (14)C6—C1—C2—C31.3 (2)
N4—C2—C3—C174.0 (2)C6—C1—C16—N2147 (9)
C1—C2—C3—C40.3 (2)C6—C5—C9—N120.08 (19)
C1—C2—C3—C17175.24 (13)C6—C7—C8—N146.68 (18)
C1—C6—C7—C8167.68 (14)C8—N1—C9—C554.58 (16)
C2—C1—C6—C51.8 (2)C9—N1—C8—C769.32 (16)
C2—C1—C6—C7178.69 (14)C9—C5—C6—C1179.00 (13)
C2—C1—C16—N234 (9)C9—C5—C6—C70.5 (2)
C2—C3—C4—C51.3 (2)C10—C4—C5—C6179.26 (13)
C2—C3—C4—C10178.81 (13)C10—C4—C5—C90.3 (2)
C2—C3—C17—N319 (2)C10—C11—C12—C130.3 (2)
C3—C4—C5—C60.9 (2)C11—C10—C15—C140.1 (2)
C3—C4—C5—C9179.50 (13)C11—C12—C13—C140.3 (2)
C3—C4—C10—C1161.30 (18)C12—C13—C14—C150.1 (2)
C3—C4—C10—C15118.16 (16)C13—C14—C15—C100.0 (2)
C4—C3—C17—N3157 (2)C15—C10—C11—C120.2 (2)
C4—C5—C6—C10.6 (2)C16—C1—C2—N41.3 (2)
C4—C5—C6—C7179.86 (13)C16—C1—C2—C3179.48 (14)
C4—C5—C9—N1159.53 (13)C16—C1—C6—C5179.03 (14)
C4—C10—C11—C12179.67 (14)C16—C1—C6—C70.5 (2)
C4—C10—C15—C14179.53 (13)C17—C3—C4—C5173.99 (13)
C5—C4—C10—C11118.85 (16)C17—C3—C4—C105.9 (2)
C5—C4—C10—C1561.68 (19)C18—N1—C8—C7169.84 (13)
C5—C6—C7—C812.8 (2)C18—N1—C9—C5176.02 (13)
C6—C1—C2—N4177.97 (15)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N4—H4A···N2i0.89 (1)2.21 (1)3.052 (2)157 (2)
N4—H4B···N1ii0.87 (1)2.21 (1)3.0261 (19)155 (2)
Symmetry codes: (i) x+1, y+1, z+1; (ii) x, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC18H16N4
Mr288.35
Crystal system, space groupMonoclinic, P21/c
Temperature (K)143
a, b, c (Å)17.5630 (5), 6.25208 (19), 13.7963 (4)
β (°) 93.209 (3)
V3)1512.53 (8)
Z4
Radiation typeMo Kα
µ (mm1)0.08
Crystal size (mm)0.38 × 0.35 × 0.25
Data collection
DiffractometerAgilent Xcalibur Eos
diffractometer
Absorption correctionMulti-scan
(CrysAlis PRO; Oxford Diffraction, 2009)
Tmin, Tmax0.960, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
6799, 3089, 2414
Rint0.034
(sin θ/λ)max1)0.625
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.045, 0.112, 1.05
No. of reflections3089
No. of parameters206
No. of restraints4
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.19, 0.22

Computer programs: CrysAlis PRO (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), OLEX2 (Dolomanov et al., 2009) and Mercury (Macrae et al., 2008), OLEX2 (Dolomanov et al., 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N4—H4A···N2i0.893 (12)2.210 (13)3.052 (2)157.1 (15)
N4—H4B···N1ii0.874 (12)2.210 (13)3.0261 (19)155.3 (15)
Symmetry codes: (i) x+1, y+1, z+1; (ii) x, y+1/2, z+1/2.
 

Acknowledgements

We thank the Analytical and Testing Center of Sichuan University for the X-ray measurements.

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