(IUCr) 1,4-Dimethyl-3-phenyl-3H-pyrazolo[3,4-c]isoquinolin-5(4H)-one

Volume 64
Part 5
Page o863
May 2008

Received 19 March 2008
Accepted 14 April 2008
Online 16 April 2008

Key indicators
Single-crystal X-ray study
T = 293 K
Mean (C-C) = 0.003 Å
R = 0.048
wR = 0.114
Data-to-parameter ratio = 13.9
Details

1,4-Dimethyl-3-phenyl-3H-pyrazolo[3,4-c]isoquinolin-5(4H)-one

Fiorella Meneghetti,^a ^* Gabriella Bombieri,^a Benedetta Maggio ^b and Giuseppe Daidone ^b

^aInstitute of Pharmaceutical and Toxicological Chemistry `P. Pratesi', University of Milan, via L. Mangiagalli 25, 20133 Milan, Italy, and ^bDepartment of Pharmaceutical and Technological Chemistry, University of Palermo, via Archirafi 32, 90123 Palermo, Italy
Correspondence e-mail: fiorella.meneghetti@unimi.it

The title compound, C₁₈H₁₅N₃O, is the product of the thermal decomposition of the diazonium salt derived from 2-amino-N-methyl-N-(3-methyl-1-phenyl-1H-pyrazol-5-yl)benzamide. It is characterized by a trans orientation of the methyl groups with respect to the tricyclic ring system. The molecule has a nearly planar phenylpyrazolo[3,4-c]isoquinolin-5-one system, the largest deviation from the mean plane being 0.066 (2) Å for the O atom. The dihedral angle between the phenyl substituent and the heterotricycle is 67 (1)°. The packing is stabilized by C-HN hydrogen-bond interactions, with the formation of molecular chains along the c axis.

Related literature

Pyrazole rings are useful templates to investigate the role of the aryldiazonium group in the Pschorr reaction pathway (Maggio et al., 2005). For related literature, see: Daidone et al. (1980, 1993, 1998).

Experimental

Crystal data

C₁₈H₁₅N₃O
M_r = 289.33
Monoclinic, P 2₁ /n
a = 8.066 (2) Å
b = 19.256 (3) Å
c = 9.270 (3) Å
= 94.66 (3)°
V = 1435.0 (6) Å³
Z = 4
Mo K radiation
= 0.09 mm^-1
T = 293 (2) K
0.6 × 0.5 × 0.4 mm

Data collection

Enraf-Nonius TurboCAD-4 diffractometer
Absorption correction: none
2984 measured reflections
2815 independent reflections
1751 reflections with I > 2(I)
R_int = 0.031
3 standard reflections frequency: 120 min intensity decay: 3%

Refinement

R[F² > 2(F²)] = 0.048
wR(F²) = 0.113
S = 1.01
2815 reflections
202 parameters
H-atom parameters constrained
_max = 0.15 e Å^-3
_min = -0.15 e Å^-3

Table 1
Hydrogen-bond geometry (Å, °)

D-HA	D-H	HA	DA	D-HA
C6-H6N1ⁱ	0.93	2.59	3.457 (3)	156
Symmetry code: (i) $[x-{\script{1\over 2}}, -y-{\script{1\over 2}}, z+{\script{1\over 2}}]$ .

Data collection: CAD-4 EXPRESS (Enraf-Nonius, 1994); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: FJ2107 ).

References

Altomare, A., Cascarano, G., Giacovazzo, C., Guagliardi, A., Burla, M. C., Polidori, G. & Camalli, M. (1994). J. Appl. Cryst. 27, 435.
Daidone, G., Maggio, B., Raffa, D., Plescia, S., Benetollo, F. & Bombieri, G. (1998). J. Chem. Soc. Perkin Trans. 1, pp. 2891-2898.
Daidone, G., Plescia, S. & Fabra, J. (1980). J. Heterocycl. Chem. 17, 1409-1411.
Daidone, G., Plescia, S., Maggio, B., Spirio, V., Benetollo, F. & Bombieri, G. (1993). J. Chem. Soc. Perkin Trans. 1, pp. 285-291.
Enraf-Nonius (1994). CAD-4 EXPRESS. Enraf-Nonius, Delft, The Netherlands.
Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.
Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.
Harms, K. & Wocadlo, S. (1995). XCAD4. University of Marburg, Germany.
Maggio, B., Daidone, G., Raffa, D., Plescia, S., Bombieri, G. & Meneghetti, F. (2005). Helv. Chim. Acta, 88, 2272-2281.
Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.

organic compounds