organic compounds
A monoclinic polymorph of 3,7,7-trimethyl-1-phenyl-5,6,7,8-tetrahydro-1H-pyrazolo[3,4-b]quinolin-5-one
aGrupo de Investigación de Compuestos Heterocíclicos, Departamento de Química, Universidad de Valle, AA 25360 Cali, Colombia, bDepartamento de Química Inorgánica y Orgánica, Universidad de Jaén, 23071 Jaén, Spain, cDepartment of Chemistry, University of Aberdeen, Meston Walk, Old Aberdeen AB24 3UE, Scotland, and dSchool of Chemistry, University of St Andrews, Fife KY16 9ST, Scotland
*Correspondence e-mail: cg@st-andrews.ac.uk
A second, monoclinic, polymorph of the title compound, C19H19N3O, is reported. In this polymorph, the molecules are linked into chains by paired C—H⋯π hydrogen bonds and the chains are linked into sheets by π stacking interactions.
Comment
The structure of a triclinic form (space group P, Z′ = 2) of the title compound, (I), has been reported recently (Low et al., 2003); the crystals were grown from an ethanol solution. We now report the structure of a monoclinic polymorph of (I) (space group P21/n, Z′ = 1; Fig. 1), for which the crystals were
grown from a dimethylformamide solution. In this polymorph, the supramolecular aggregation shows some interesting differences from both that of the triclinic form and that of the analogous compound 3-tert-butyl-7,7-dimethyl-1-phenyl-5,6,7,8-tetrahydropyrazolo[3,4-b]quinolin-5-one, (II) (Low et al., 2004). For convenience, we denote the monoclinic polymorph reported here as (Ia) and the previously reported triclinic polymorph as (Ib).The bond lengths in monoclinic polymorph (Ia) are very similar to those in both the triclinic polymorph (Ib) and (II), and thus require no further discussion here. The ring-puckering parameters (Cremer & Pople, 1975) for the carbocyclic ring in monoclinic (Ia) are θ = 52.1 (2)° and φ = 167.4 (4)° for the atom sequence C4a—C5—C6—C7—C8—C8a, with a total puckering amplitude Q = 0.489 (2) Å; these parameters indicate an for this ring (Evans & Boeyens, 1989), with the ring folded across the vector C6⋯C8. In this respect, (Ia) is very similar both to (Ib) and to (II). However, the patterns of supramolecular aggregation in (Ia), (Ib) and (II) are entirely different.
In monoclinic (Ia), the molecules are linked into chains by two independent C—H⋯π hydrogen bonds acting in concert, and the resulting chains are linked into sheets by π stacking interactions; however, C—H⋯O and C—H⋯N hydrogen bonds are absent from the structure of (I). By contrast, the molecules in triclinic (Ib) are linked into ribbons by a combination of C—H⋯O, C—H⋯N and C—H⋯π hydrogen bonds, while the molecules of (II) are linked into chains by a single C—H⋯N hydrogen bond; however, C—H⋯π hydrogen bonds and π stacking interactions are both absent from the structure of (II).
Atoms C6 and C8 in the molecule of (Ia) at (x, y, z) act as hydrogen-bond donors, via the axial atoms H6A and H8A, respectively, to the pyrazole and aryl rings of the molecule at (− + x, − y, − + z), thereby forming a [101] chain generated by the n-glide plane at y = 0.75 (Fig. 2). We may note here that the exactly corresponding pair of C—H bonds act as donors to aryl and pyrazole rings in the analogous chloro-substituted compound 3-tert-butyl-1-(4-chlorophenyl)-7,7-dimethyl-5,6,7,8-tetrahydropyrazolo[3,4-b]quinolin-5-one, (III), but such that H6A is donor to the aryl ring and H8A is donor to the pyrazole ring in a cyclic centrosymmetric dimer (Low et al., 2005).
The hydrogen-bonded chains in polymorph (Ia) are linked into sheets by π stacking interactions. The pyrazole rings in the molecules at (x, y, z) and (1 − x, 1 − y, 1 − z) are strictly parallel, with an interplanar spacing of 3.311 (2) Å, a ring centroid separation of 3.416 (2) Å and a centroid offset of 0.841 (2) Å; at the same time, the pyrazole ring at (x, y, z) and the pyridine ring containing N9 at (1 − x, 1 − y, 1 − z) make an interplanar angle of only 1.1 (2)°; the interplanar spacing is ca 3.30 Å, the corresponding ring centroid separation is 3.547 (2) Å and the centroid offset is 1.300 (2) Å (Fig. 3). The molecules at (x, y, z) and (1 − x, 1 − y, 1 − z) form parts of the hydrogen-bonded chains generated by the n-glide planes at y = 0.75 and y = 0.25, respectively; hence, propagation by the of these π stacking interactions links all of the [101] chains into a (10) sheet (Fig. 4); however, there are no direction-specific interactions between adjacent sheets.
Experimental
The title compound was prepared as described previously (Low et al., 2003). Crystals suitable for single-crystal X-ray diffraction were grown by slow evaporation of a dimethylformamide solution.
Crystal data
|
Data collection
Refinement
|
The P21/n was uniquely assigned from the All H atoms were located from difference maps and then treated as riding atoms, with C—H distances of 0.95 (aromatic), 0.98 (methyl) or 0.99 Å (CH2), and with Uiso(H) = 1.2Ueq(C), or 1.5Ueq(C) for the methyl groups.
Data collection: COLLECT (Hooft, 1999); cell DENZO (Otwinowski & Minor, 1997) and COLLECT; data reduction: DENZO and COLLECT; program(s) used to solve structure: OSCAIL (McArdle, 2003) and SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: OSCAIL and SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97 and PRPKAPPA (Ferguson, 1999).
Supporting information
10.1107/S0108270105016501/sk1847sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S0108270105016501/sk1847Isup2.hkl
The title compound was prepared as previously described (Low et al., 2003). Crystals suitable for single-crystal X-ray diffraction were grown by slow evaporation of a dimethylformamide solution.
The
P21/n was uniquely assigned from the All H atoms were located from difference maps, and then treated as riding atoms with C—H distances of 0.95 Å (aromatic), 0.98 Å (methyl) or 0.99 Å (CH2), and with Uiso(H) = 1.2Ueq(C), or 1.5Ueq(C) for the methyl groups.Data collection: COLLECT (Hooft, 1999); cell
DENZO (Otwinowski & Minor, 1997) and COLLECT; data reduction: DENZO and COLLECT; program(s) used to solve structure: OSCAIL (McArdle, 2003) and SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: OSCAIL and SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97 and PRPKAPPA (Ferguson, 1999).C19H19N3O | F(000) = 648 |
Mr = 305.37 | Dx = 1.324 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 3503 reflections |
a = 11.1485 (12) Å | θ = 3.8–27.6° |
b = 12.3739 (15) Å | µ = 0.08 mm−1 |
c = 11.7412 (12) Å | T = 120 K |
β = 108.894 (6)° | Block, colourless |
V = 1532.4 (3) Å3 | 0.34 × 0.23 × 0.13 mm |
Z = 4 |
Bruker-Nonius 95mm CCD camera on κ goniostat diffractometer | 3503 independent reflections |
Radiation source: Bruker–Nonius FR91 rotating anode | 2030 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.090 |
Detector resolution: 9.091 pixels mm-1 | θmax = 27.6°, θmin = 3.8° |
ϕ and ω scans | h = −14→14 |
Absorption correction: multi-scan (SADABS; Sheldrick, 2003) | k = −15→16 |
Tmin = 0.967, Tmax = 0.989 | l = −15→15 |
17074 measured reflections |
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)] = 0.065 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.179 | H-atom parameters constrained |
S = 1.03 | w = 1/[σ2(Fo2) + (0.0933P)2 + 0.13P] where P = (Fo2 + 2Fc2)/3 |
3503 reflections | (Δ/σ)max < 0.001 |
211 parameters | Δρmax = 0.28 e Å−3 |
0 restraints | Δρmin = −0.30 e Å−3 |
C19H19N3O | V = 1532.4 (3) Å3 |
Mr = 305.37 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 11.1485 (12) Å | µ = 0.08 mm−1 |
b = 12.3739 (15) Å | T = 120 K |
c = 11.7412 (12) Å | 0.34 × 0.23 × 0.13 mm |
β = 108.894 (6)° |
Bruker-Nonius 95mm CCD camera on κ goniostat diffractometer | 3503 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 2003) | 2030 reflections with I > 2σ(I) |
Tmin = 0.967, Tmax = 0.989 | Rint = 0.090 |
17074 measured reflections |
R[F2 > 2σ(F2)] = 0.065 | 0 restraints |
wR(F2) = 0.179 | H-atom parameters constrained |
S = 1.03 | Δρmax = 0.28 e Å−3 |
3503 reflections | Δρmin = −0.30 e Å−3 |
211 parameters |
x | y | z | Uiso*/Ueq | ||
O5 | 0.06313 (14) | 0.59447 (13) | 0.18537 (14) | 0.0376 (4) | |
N1 | 0.63008 (16) | 0.63171 (15) | 0.50347 (16) | 0.0293 (5) | |
N2 | 0.59896 (17) | 0.64830 (15) | 0.60774 (16) | 0.0325 (5) | |
N9 | 0.51581 (16) | 0.60051 (15) | 0.29234 (16) | 0.0305 (5) | |
C3 | 0.4742 (2) | 0.64810 (18) | 0.5768 (2) | 0.0308 (5) | |
C3A | 0.4188 (2) | 0.63089 (17) | 0.4500 (2) | 0.0293 (5) | |
C4 | 0.2983 (2) | 0.62201 (17) | 0.3674 (2) | 0.0296 (5) | |
C4A | 0.2870 (2) | 0.60329 (18) | 0.24814 (19) | 0.0281 (5) | |
C5 | 0.1589 (2) | 0.59384 (18) | 0.1562 (2) | 0.0296 (5) | |
C6 | 0.1544 (2) | 0.58424 (19) | 0.0276 (2) | 0.0315 (6) | |
C7 | 0.26272 (19) | 0.51538 (19) | 0.01188 (19) | 0.0321 (6) | |
C8 | 0.38796 (19) | 0.56800 (19) | 0.08644 (19) | 0.0325 (6) | |
C8A | 0.39794 (19) | 0.59121 (17) | 0.2146 (2) | 0.0288 (5) | |
C9A | 0.5219 (2) | 0.62022 (17) | 0.4062 (2) | 0.0278 (5) | |
C11 | 0.7611 (2) | 0.63359 (17) | 0.5127 (2) | 0.0292 (5) | |
C12 | 0.8519 (2) | 0.63701 (19) | 0.6265 (2) | 0.0341 (6) | |
C13 | 0.9787 (2) | 0.6423 (2) | 0.6372 (2) | 0.0386 (6) | |
C14 | 1.0161 (2) | 0.64317 (19) | 0.5358 (2) | 0.0371 (6) | |
C15 | 0.9259 (2) | 0.63880 (19) | 0.4233 (2) | 0.0371 (6) | |
C16 | 0.7982 (2) | 0.63443 (19) | 0.4109 (2) | 0.0349 (6) | |
C31 | 0.4094 (2) | 0.6631 (2) | 0.6683 (2) | 0.0362 (6) | |
C71 | 0.2541 (2) | 0.39993 (19) | 0.0545 (2) | 0.0387 (6) | |
C72 | 0.2529 (2) | 0.5139 (2) | −0.12062 (19) | 0.0383 (6) | |
H4 | 0.2253 | 0.6286 | 0.3919 | 0.036* | |
H6A | 0.1585 | 0.6575 | −0.0049 | 0.038* | |
H6B | 0.0724 | 0.5517 | −0.0201 | 0.038* | |
H8A | 0.3983 | 0.6366 | 0.0472 | 0.039* | |
H8B | 0.4586 | 0.5198 | 0.0860 | 0.039* | |
H12 | 0.8268 | 0.6357 | 0.6965 | 0.041* | |
H13 | 1.0408 | 0.6455 | 0.7148 | 0.046* | |
H14 | 1.1036 | 0.6467 | 0.5437 | 0.044* | |
H15 | 0.9516 | 0.6388 | 0.3536 | 0.045* | |
H16 | 0.7363 | 0.6320 | 0.3330 | 0.042* | |
H31A | 0.4730 | 0.6699 | 0.7483 | 0.054* | |
H31B | 0.3551 | 0.6006 | 0.6670 | 0.054* | |
H31C | 0.3575 | 0.7288 | 0.6497 | 0.054* | |
H71A | 0.1704 | 0.3700 | 0.0109 | 0.058* | |
H71B | 0.2664 | 0.4002 | 0.1410 | 0.058* | |
H71C | 0.3198 | 0.3555 | 0.0389 | 0.058* | |
H72A | 0.1714 | 0.4825 | −0.1682 | 0.057* | |
H72B | 0.3221 | 0.4704 | −0.1309 | 0.057* | |
H72C | 0.2589 | 0.5879 | −0.1480 | 0.057* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O5 | 0.0209 (8) | 0.0547 (11) | 0.0411 (10) | 0.0001 (7) | 0.0152 (7) | −0.0003 (8) |
N1 | 0.0198 (10) | 0.0410 (12) | 0.0284 (10) | −0.0010 (8) | 0.0096 (8) | −0.0008 (8) |
N2 | 0.0288 (11) | 0.0409 (12) | 0.0299 (11) | −0.0013 (8) | 0.0127 (9) | −0.0015 (8) |
N9 | 0.0214 (10) | 0.0403 (11) | 0.0303 (11) | −0.0033 (8) | 0.0093 (8) | −0.0028 (8) |
C3 | 0.0252 (12) | 0.0348 (13) | 0.0330 (13) | −0.0009 (10) | 0.0106 (10) | −0.0015 (10) |
C3A | 0.0253 (12) | 0.0323 (13) | 0.0332 (13) | 0.0014 (9) | 0.0135 (10) | 0.0003 (10) |
C4 | 0.0220 (12) | 0.0356 (13) | 0.0345 (13) | −0.0004 (9) | 0.0135 (10) | −0.0005 (10) |
C4A | 0.0215 (11) | 0.0340 (13) | 0.0302 (13) | 0.0005 (9) | 0.0105 (10) | 0.0000 (9) |
C5 | 0.0220 (11) | 0.0329 (13) | 0.0352 (13) | −0.0004 (9) | 0.0113 (10) | 0.0000 (10) |
C6 | 0.0212 (11) | 0.0406 (14) | 0.0339 (13) | −0.0008 (10) | 0.0104 (10) | 0.0001 (10) |
C7 | 0.0191 (11) | 0.0448 (14) | 0.0331 (13) | −0.0004 (10) | 0.0092 (9) | −0.0015 (11) |
C8 | 0.0205 (11) | 0.0461 (15) | 0.0327 (13) | 0.0008 (10) | 0.0112 (10) | −0.0014 (11) |
C8A | 0.0206 (11) | 0.0327 (13) | 0.0337 (13) | −0.0015 (9) | 0.0095 (10) | −0.0014 (10) |
C9A | 0.0201 (11) | 0.0324 (13) | 0.0312 (13) | 0.0002 (9) | 0.0088 (10) | 0.0003 (9) |
C11 | 0.0214 (11) | 0.0304 (13) | 0.0370 (13) | 0.0008 (9) | 0.0109 (10) | 0.0000 (10) |
C12 | 0.0261 (12) | 0.0462 (15) | 0.0306 (13) | 0.0008 (10) | 0.0099 (11) | 0.0011 (10) |
C13 | 0.0230 (12) | 0.0508 (15) | 0.0380 (14) | 0.0023 (11) | 0.0045 (11) | 0.0030 (11) |
C14 | 0.0194 (12) | 0.0498 (16) | 0.0426 (15) | 0.0021 (10) | 0.0109 (11) | 0.0006 (11) |
C15 | 0.0276 (12) | 0.0486 (15) | 0.0384 (14) | 0.0006 (11) | 0.0152 (11) | −0.0002 (11) |
C16 | 0.0244 (12) | 0.0473 (15) | 0.0334 (13) | −0.0010 (10) | 0.0096 (10) | −0.0023 (11) |
C31 | 0.0284 (12) | 0.0489 (15) | 0.0334 (13) | −0.0001 (11) | 0.0131 (11) | 0.0000 (11) |
C71 | 0.0294 (13) | 0.0467 (16) | 0.0404 (14) | 0.0018 (11) | 0.0117 (11) | −0.0046 (11) |
C72 | 0.0213 (11) | 0.0581 (17) | 0.0361 (14) | −0.0006 (11) | 0.0103 (10) | −0.0040 (11) |
N1—C9A | 1.373 (3) | C4—H4 | 0.95 |
N1—N2 | 1.392 (3) | C4A—C8A | 1.422 (3) |
N1—C11 | 1.429 (3) | C4A—C5 | 1.491 (3) |
C11—C16 | 1.386 (3) | C5—O5 | 1.222 (2) |
C11—C12 | 1.392 (3) | C5—C6 | 1.499 (3) |
C12—C13 | 1.380 (3) | C6—C7 | 1.537 (3) |
C12—H12 | 0.95 | C6—H6A | 0.99 |
C13—C14 | 1.383 (3) | C6—H6B | 0.99 |
C13—H13 | 0.95 | C7—C72 | 1.524 (3) |
C14—C15 | 1.378 (3) | C7—C71 | 1.527 (3) |
C14—H14 | 0.95 | C7—C8 | 1.532 (3) |
C15—C16 | 1.385 (3) | C71—H71A | 0.98 |
C15—H15 | 0.95 | C71—H71B | 0.98 |
C16—H16 | 0.95 | C71—H71C | 0.98 |
N2—C3 | 1.319 (3) | C72—H72A | 0.98 |
C3—C3A | 1.431 (3) | C72—H72B | 0.98 |
C3—C31 | 1.487 (3) | C72—H72C | 0.98 |
C31—H31A | 0.98 | C8—C8A | 1.500 (3) |
C31—H31B | 0.98 | C8—H8A | 0.99 |
C31—H31C | 0.98 | C8—H8B | 0.99 |
C3A—C4 | 1.383 (3) | C8A—N9 | 1.340 (3) |
C3A—C9A | 1.409 (3) | N9—C9A | 1.339 (3) |
C4—C4A | 1.384 (3) | ||
C9A—N1—N2 | 110.19 (16) | O5—C5—C4A | 121.0 (2) |
C9A—N1—C11 | 131.70 (19) | O5—C5—C6 | 122.4 (2) |
N2—N1—C11 | 118.06 (18) | C4A—C5—C6 | 116.58 (18) |
C16—C11—C12 | 120.0 (2) | C5—C6—C7 | 113.16 (18) |
C16—C11—N1 | 121.2 (2) | C5—C6—H6A | 108.9 |
C12—C11—N1 | 118.8 (2) | C7—C6—H6A | 108.9 |
C13—C12—C11 | 119.6 (2) | C5—C6—H6B | 108.9 |
C13—C12—H12 | 120.2 | C7—C6—H6B | 108.9 |
C11—C12—H12 | 120.2 | H6A—C6—H6B | 107.8 |
C12—C13—C14 | 120.6 (2) | C72—C7—C71 | 109.39 (19) |
C12—C13—H13 | 119.7 | C72—C7—C8 | 109.84 (18) |
C14—C13—H13 | 119.7 | C71—C7—C8 | 110.67 (18) |
C15—C14—C13 | 119.7 (2) | C72—C7—C6 | 109.22 (18) |
C15—C14—H14 | 120.2 | C71—C7—C6 | 110.11 (18) |
C13—C14—H14 | 120.2 | C8—C7—C6 | 107.57 (18) |
C14—C15—C16 | 120.6 (2) | C7—C71—H71A | 109.5 |
C14—C15—H15 | 119.7 | C7—C71—H71B | 109.5 |
C16—C15—H15 | 119.7 | H71A—C71—H71B | 109.5 |
C15—C16—C11 | 119.6 (2) | C7—C71—H71C | 109.5 |
C15—C16—H16 | 120.2 | H71A—C71—H71C | 109.5 |
C11—C16—H16 | 120.2 | H71B—C71—H71C | 109.5 |
C3—N2—N1 | 107.38 (18) | C7—C72—H72A | 109.5 |
N2—C3—C3A | 110.4 (2) | C7—C72—H72B | 109.5 |
N2—C3—C31 | 121.1 (2) | H72A—C72—H72B | 109.5 |
C3A—C3—C31 | 128.6 (2) | C7—C72—H72C | 109.5 |
C3—C31—H31A | 109.5 | H72A—C72—H72C | 109.5 |
C3—C31—H31B | 109.5 | H72B—C72—H72C | 109.5 |
H31A—C31—H31B | 109.5 | C8A—C8—C7 | 114.35 (18) |
C3—C31—H31C | 109.5 | C8A—C8—H8B | 108.7 |
H31A—C31—H31C | 109.5 | C7—C8—H8A | 108.7 |
H31B—C31—H31C | 109.5 | C8A—C8—H8B | 108.7 |
C4—C3A—C9A | 117.3 (2) | C7—C8—H8A | 108.7 |
C4—C3A—C3 | 137.3 (2) | H8A—C8—H8B | 107.6 |
C9A—C3A—C3 | 105.40 (19) | N9—C8A—C4A | 123.45 (19) |
C3A—C4—C4A | 118.1 (2) | N9—C8A—C8 | 115.93 (18) |
C3A—C4—H4 | 120.9 | C4A—C8A—C8 | 120.61 (19) |
C4A—C4—H4 | 120.9 | C9A—N9—C8A | 114.67 (18) |
C4—C4A—C8A | 119.7 (2) | N9—C9A—N1 | 126.62 (19) |
C4—C4A—C5 | 119.85 (19) | N9—C9A—C3A | 126.7 (2) |
C8A—C4A—C5 | 120.44 (19) | N1—C9A—C3A | 106.68 (19) |
C9A—N1—C11—C16 | 7.1 (4) | C8A—C4A—C5—C6 | −6.9 (3) |
N2—N1—C11—C16 | −169.93 (19) | O5—C5—C6—C7 | −142.7 (2) |
C9A—N1—C11—C12 | −174.3 (2) | C4A—C5—C6—C7 | 37.6 (3) |
N2—N1—C11—C12 | 8.7 (3) | C5—C6—C7—C72 | −177.91 (19) |
C16—C11—C12—C13 | 0.7 (3) | C5—C6—C7—C71 | 62.0 (2) |
N1—C11—C12—C13 | −177.9 (2) | C5—C6—C7—C8 | −58.7 (2) |
C11—C12—C13—C14 | −0.7 (3) | C72—C7—C8—C8A | 169.93 (18) |
C12—C13—C14—C15 | 0.1 (4) | C71—C7—C8—C8A | −69.2 (2) |
C13—C14—C15—C16 | 0.5 (4) | C6—C7—C8—C8A | 51.2 (3) |
C14—C15—C16—C11 | −0.5 (4) | C4—C4A—C8A—N9 | −2.3 (3) |
C12—C11—C16—C15 | −0.1 (3) | C5—C4A—C8A—N9 | 178.9 (2) |
N1—C11—C16—C15 | 178.5 (2) | C4—C4A—C8A—C8 | 178.4 (2) |
C9A—N1—N2—C3 | −0.5 (2) | C5—C4A—C8A—C8 | −0.4 (3) |
C11—N1—N2—C3 | 177.16 (18) | C7—C8—C8A—N9 | 157.37 (19) |
N1—N2—C3—C3A | 0.2 (2) | C7—C8—C8A—C4A | −23.3 (3) |
N1—N2—C3—C31 | 179.55 (19) | C4A—C8A—N9—C9A | 1.3 (3) |
N2—C3—C3A—C4 | 179.5 (3) | C8—C8A—N9—C9A | −179.42 (19) |
C31—C3—C3A—C4 | 0.1 (4) | C8A—N9—C9A—N1 | 179.0 (2) |
N2—C3—C3A—C9A | 0.2 (2) | C8A—N9—C9A—C3A | 0.5 (3) |
C31—C3—C3A—C9A | −179.2 (2) | N2—N1—C9A—N9 | −178.2 (2) |
C9A—C3A—C4—C4A | 0.0 (3) | C11—N1—C9A—N9 | 4.6 (4) |
C3—C3A—C4—C4A | −179.2 (2) | N2—N1—C9A—C3A | 0.6 (2) |
C3A—C4—C4A—C8A | 1.5 (3) | C11—N1—C9A—C3A | −176.6 (2) |
C3A—C4—C4A—C5 | −179.6 (2) | C4—C3A—C9A—N9 | −1.1 (3) |
C4—C4A—C5—O5 | −5.4 (3) | C3—C3A—C9A—N9 | 178.3 (2) |
C8A—C4A—C5—O5 | 173.4 (2) | C4—C3A—C9A—N1 | −179.90 (19) |
C4—C4A—C5—C6 | 174.3 (2) | C3—C3A—C9A—N1 | −0.4 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
C6—H6A···Cg1i | 0.99 | 2.97 | 3.716 (3) | 133 |
C8—H8A···Cg2i | 0.99 | 2.80 | 3.708 (3) | 153 |
Symmetry code: (i) x−1/2, −y+3/2, z−1/2. |
Experimental details
Crystal data | |
Chemical formula | C19H19N3O |
Mr | 305.37 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 120 |
a, b, c (Å) | 11.1485 (12), 12.3739 (15), 11.7412 (12) |
β (°) | 108.894 (6) |
V (Å3) | 1532.4 (3) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.08 |
Crystal size (mm) | 0.34 × 0.23 × 0.13 |
Data collection | |
Diffractometer | Bruker-Nonius 95mm CCD camera on κ goniostat diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 2003) |
Tmin, Tmax | 0.967, 0.989 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 17074, 3503, 2030 |
Rint | 0.090 |
(sin θ/λ)max (Å−1) | 0.653 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.065, 0.179, 1.03 |
No. of reflections | 3503 |
No. of parameters | 211 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.28, −0.30 |
Computer programs: COLLECT (Hooft, 1999), DENZO (Otwinowski & Minor, 1997) and COLLECT, DENZO and COLLECT, OSCAIL (McArdle, 2003) and SHELXS97 (Sheldrick, 1997), OSCAIL and SHELXL97 (Sheldrick, 1997), PLATON (Spek, 2003), SHELXL97 and PRPKAPPA (Ferguson, 1999).
D—H···A | D—H | H···A | D···A | D—H···A |
C6—H6A···Cg1i | 0.99 | 2.97 | 3.716 (3) | 133 |
C8—H8A···Cg2i | 0.99 | 2.80 | 3.708 (3) | 153 |
Symmetry code: (i) x−1/2, −y+3/2, z−1/2. |
Acknowledgements
X-ray data were collected at the EPSRC X-ray Crystallographic Service, University of Southampton, England, using a Nonius KappaCCD diffractometer. JC thanks the Consejería de Innovación, Ciencia y Empresa (Junta de Andalucía, Spain) and the Universidad de Jaén for financial support. JQ and JM thank COLCIENCIAS and UNIVALLE (Universidad del Valle, Colombia) for financial support.
References
Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354–1358. CrossRef CAS Web of Science Google Scholar
Evans, D. G. & Boeyens, J. C. A. (1989). Acta Cryst. B45, 581–590. CrossRef CAS Web of Science IUCr Journals Google Scholar
Ferguson, G. (1999). PRPKAPPA. University of Guelph, Canada. Google Scholar
Hooft, R. W. W. (1999). COLLECT. Nonius BV, Delft, The Netherlands. Google Scholar
Low, J. N., Cobo, J., Mera, J., Quiroga, J. & Glidewell, C. (2004). Acta Cryst. C60, o479–o482. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Low, J. N., Cobo, J., Mera, J., Quiroga, J. & Glidewell, C. (2005). Acta Cryst. E61, o49–o51. Web of Science CSD CrossRef IUCr Journals Google Scholar
Low, J. N., Mera, J., Quiroga, J. & Cobo, J. (2003). Acta Cryst. E59, o1804–o1806. Web of Science CSD CrossRef IUCr Journals Google Scholar
McArdle, P. (2003). OSCAIL for Windows. Version 10. Crystallography Centre, Chemistry Department, NUI Galway, Ireland. Google Scholar
Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307–326. New York: Academic Press. Google Scholar
Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany. Google Scholar
Sheldrick, G. M. (2003). SADABS. Version 2.10. University of Göttingen, Germany. Google Scholar
Spek, A. L. (2003). J. Appl. Cryst. 36, 7–13. Web of Science CrossRef CAS IUCr Journals Google Scholar
© International Union of Crystallography. Prior permission is not required to reproduce short quotations, tables and figures from this article, provided the original authors and source are cited. For more information, click here.
The structure of a triclinic form (space group P1, Z' = 2) of the title compound, (I), has been reported recently (Low et al., 2003); the crystals were grown from an ethanol solution. We now report the structure of a monoclinic polymorph of (I) (space group P21/n, Z' = 1; Fig. 1), for which the crystals were grown from a dimethylformamide solution. In this polymorph, the supramolecular aggregation shows some interesting differences from both that of the triclinic form and that of the analogous compound 3-tert-butyl-7,7-dimethyl-1-phenyl-5,6,7,8-tetrahydropyrazolo[3,4-b]quinolin-5-one, (II) (Low et al., 2004). For convenience, we denote the monoclinic polymorph reported here as (Ia) and the previously reported triclinic polymorph as (Ib).
The bond lengths in monoclinic polymorph (Ia) are very similar to those in both the triclinic polymorph (Ib) and (II), and thus require no further discussion here. The ring-puckering parameters (Cremer & Pople, 1975) for the carbocyclic ring in monoclinic (Ia) are θ = 52.1 (2)° and ϕ = 167.4 (4)° for the atom sequence C4a—C5—C6—C7—C8—C8a, with a total puckering amplitude Q = 0.489 (2) Å; these parameters indicate an envelope conformation for this ring (Evans & Boeyens, 1989), with the ring folded across the vector C6···C8. In this respect, (Ia) is very similar both to (Ib) and to (II). However, the patterns of supramolecular aggregation in (Ia), (Ib) and (II) are entirely different.
In monoclinic (Ia), the molecules are linked into chains by two independent C—H···π hydrogen bonds acting in concert, and the resulting chains are linked into sheets by π-stacking interactions; however, C—H···O and C—H···N hydrogen bonds are absent from the structure of (I). By contrast, the molecules in triclinic (Ib) are linked into ribbons by a combination of C—H···O, C—H···N and C—H···π hydrogen bonds, while the molecules of (II) are linked into chains by a single C—H···N hydrogen bond; however, C—H···π hydrogen bonds and π stacking interactions are both absent from the structure of (II).
Atoms C6 and C8 in the molecule of (Ia) at (x, y, z) act as hydrogen-bond donors, via the axial atoms H6A and H8A, respectively, to the pyrazole and aryl rings of the molecule at (−1/2 + x, 1.5 − y, −1/2 + z), thereby forming a [101] chain generated by the n-glide plane at y = 0.75 (Fig. 2). We may note here that the exactly corresponding pair of C—H bonds act as donors to aryl and pyrazole rings in the analogous chloro-substituted compound 3-tert-butyl-7,7-dimethyl-1-(4-chlorophenyl)-5,6,7,8-tetrahydropyrazolo[3,4-b]quinolin-5-one, (III), but such that H6A is donor to the aryl ring and H8A is donor to the pyrazole ring in a cyclic centrosymmetric dimer (Low et al., 2005).
The hydrogen-bonded chains in polymorph (Ia) are linked into sheets by π stacking interactions. The pyrazole rings in the molecules at (x, y, z) and (1 − x, 1 − y, 1 − z) are strictly parallel with an interplanar spacing of 3.311 (2) Å, and a ring centroid separation of 3.416 (2) Å, giving a centroid offset of 0.841 (2) Å; at the same time, the pyrazole ring at (x, y, z) and the pyridine ring containing N9 at (1 − x, 1 − y, 1 − z) make an interplanar angle of only 1.1 (2)°; the interplanar spacing is ca 3.30 Å, with a corresponding ring centroid separation of 3.547 (2) ° and a centroid offset of 1.300 (2) Å (Fig. 3). The molecules at (x, y, z) and (1 − x, 1 − y, 1 − z) form parts of the hydrogen -bonded chains generated by the n-glide panes at y = 0.75 and y = 1/4, respectively; hence, propagation by the space group of these π stacking interactions links all of the [101] chains into a (101) sheet (Fig. 4); however, there are no direction-specific interactions between adjacent sheets.