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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 65| Part 11| November 2009| Pages o2788-o2789
https://doi.org/10.1107/S1600536809037647

1-(2-Methyl-5-nitro­phenyl)guanidinium picrate

Jerry P. Jasinski,a Ray J. Butcher,b* M. T. Swamy,c H. S. Yathirajanc and A. R. Rameshad

aDepartment of Chemistry, Keene State College, 229 Main Street, Keene, NH 03435-2001, USA, bDepartment of Chemistry, Howard University, 525 College Street NW, Washington, DC 20059, USA, cDepartment of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore 570 006, India, and dRL Fine Chem, Bangalore 560 064, India
*Correspondence e-mail: rbutcher99@yahoo.com

(Received 13 July 2009; accepted 17 September 2009; online 17 October 2009)

In the crystal structure of the title salt, C8H11N4O2+·C6H2N3O7−, the pictrate anion participates in extensive hydrogen bonding with the guanidinium ion group of the cation, linking the mol­ecules through N+—H⋯O− hydrogen bonds and inter­molecular N—H⋯O and C—H⋯O inter­actions. These hydrogen-bonding configurations involve two three-centre/bifurcated bonds [N—H⋯(O,O)] that are observed between two N atoms from the guanidinium ion group of the cation and the o-NO2 and phenolate O atoms of the picrate anion. In addition, π–π inter­actions also contribute to the crystal packing, with a centroid-to-centroid distance of 3.693 (6) Å and a slippage angle of 1.614°. A significant number of conformational differences are observed between the salt in the crystal structure and the models obtained by density functional theory (DFT) calculations of the geometry-optimized structure.

Related literature

For background literature, see: Berlinck (2002[Berlinck, R. G. S. (2002). Nat. Prod. Rep. 19, 617-649.]); Heys et al. (2000[Heys, L., Moore, C. G. & Murphy, P. J. (2000). Chem. Soc. Rev. 29, 57-67.]); Ishikawa & Isobe (2002[Ishikawa, T. & Isobe, T. (2002). Chem. Eur. J. 8, 552-557.]); Kelley et al. (2001[Kelley, M. T., Burckstummer, T., Wenzel-Seifert, K., Dove, S., Buschauer, A. & Seifert, R. (2001). Mol. Pharm. 60, 1210-1225.]); Laeckmann et al. (2002[Laeckmann, D., Rogister, F., Dejardin, J.-V., Prosperi-Meys, C., Geczy, J., Delarge, J. & Masereel, B. (2002). Bioorg. Med. Chem. 10, 1793-1804.]); Moroni et al. (2001[Moroni, M., Koksch, B., Osipov, S. N., Crucianelli, M., Frigerio, M., Bravo, P. & Burger, K. (2001). J. Org. Chem. 66, 130-133.]); Orner & Hamilton (2001[Orner, B. P. & Hamilton, A. D. (2001). J. Inclusion Phenom. Macrocycl. Chem. 41, 141-147.]); Zyss et al. (1993[Zyss, J., Pecaut, J., Levy, J. P. & Masse, R. (1993). Acta Cryst. B49, 334-342.]). For related structures, see: Cunningham et al. (1997[Cunningham, I. D., Wan, N. C., Povey, D. C., Smith, G. W. & Cox, B. G. (1997). Acta Cryst. C53, 984-985.]); Demir et al. (2006[Demir, S., Dinçer, M. & Sarıpınar, E. (2006). Acta Cryst. E62, o4194-o4195.]); Gupta & Dutta (1975[Gupta, M. P. & Dutta, B. P. (1975). Acta Cryst. B31, 1272-1275.]); Moghimi et al. (2005[Moghimi, A., Aghabozorg, H., Soleimannejad, J. & Ramezanipour, F. (2005). Acta Cryst. E61, o442-o444.]); Murtaza et al. (2007[Murtaza, G., Hanif-Ur-Rehman,, Khawar Rauf, M., Ebihara, M. & Badshah, A. (2009). Acta Cryst. E65, o343.], 2009[Murtaza, G., Said, M., Rauf, M. K., Ebihara, M. & Badshah, A. (2007). Acta Cryst. E63, o4664.]); Pereira Silva et al. (2007[Pereira Silva, P. S., Ramos Silva, M., Paixão, J. A. & Matos Beja, A. (2007). Acta Cryst. E63, o2524-o2526.]); Pruszynski et al. (1992[Pruszynski, P., Leffek, K. T., Borecka, B. & Cameron, T. S. (1992). Acta Cryst. C48, 1638-1641.]); Ren et al. (2007[Ren, H., Cai, C., Liu, J.-Z. & Wang, J.-W. (2007). Acta Cryst. E63, o306-o307.]); Sonar et al. (2007[Sonar, V. N., Neelakantan, S., Siegler, M. & Crooks, P. A. (2007). Acta Cryst. E63, o535-o536.]); Smith et al. (2007[Smith, G., Wermuth, U. D., Healy, P. C. & White, J. M. (2007). Acta Cryst. E63, o7-o9.], 2007a[Smith, G., Wermuth, U. D. & White, J. M. (2007a). Acta Cryst. E63, o3759.]); Stanford et al. (2007[Stanford, D. J., Fernandez, R. A., Zeller, M. & Hunter, A. D. (2007). Acta Cryst. E63, o1934-o1936.]); Stępień & Grabowski (1977[Stępień, A. & Grabowski, M. J. (1977). Acta Cryst. B33, 2924-2927.]); Wang et al. (2009[Wang, W.-F., Wei, C.-M. & Zhu, H.-J. (2009). Acta Cryst. E65, o980.]); Wei (2008[Wei, C.-M. (2008). Acta Cryst. E64, o1244.]). For density functional theory (DFT), see: Becke (1988[Becke, A. D. (1988). Phys. Rev. A, 38, 3098-100.], 1993[Becke, A. D. (1993). J. Chem. Phys. 98, 5648-5652.]); Frisch et al. (2004[Frisch, M. J., et al. (2004). GAUSSIAN03. Gaussian Inc., Wallingford, Connecticut, USA.]); Hehre et al. (1986[Hehre, W. J., Random, L., Schleyer, P. von R. & Pople, J. A. (1986). Ab Initio Molecular Orbital Theory. New York: Wiley.]); Lee et al. (1988[Lee, C., Yang, W. & Parr, R. G. (1988). Phys. Rev. B, 37, 785-789.]); Schmidt & Polik (2007[Schmidt, J. R. & Polik, W. F. (2007). WebMO Pro. WebMO LLC, Holland, Michigan, USA. http://www.webmo.net.]). For the Cambridge Structural Database, see: Allen (2002[Allen, F. H. (2002). Acta Cryst. B58, 380-388.]); Bruno et al. (2004[Bruno, I. J., Cole, J. C., Kessler, M., Luo, J., Motherwell, W. D. S., Purkis, L. H., Smith, B. R., Taylor, R., Cooper, R. I., Harris, S. E. & Orpen, A. G. (2004). J. Chem. Inf. Comput. Sci. 44, 2133-2144.]).

[Scheme 1]

Experimental

Crystal data

  • C8H11N4O2+·C6H2N3O7−

  • Mr = 423.31

  • Triclinic, [P \overline 1]

  • a = 7.1318 (10) Å

  • b = 10.6239 (13) Å

  • c = 11.9564 (13) Å

  • α = 84.257 (10)°

  • β = 74.497 (11)°

  • γ = 77.559 (11)°

  • V = 851.58 (18) Å3

  • Z = 2

  • Cu Kα radiation

  • μ = 1.23 mm−1

  • T = 110 K

  • 0.51 × 0.41 × 0.33 mm
Data collection

  • Oxford Xcalibur diffractometer with Ruby (Gemini Cu) detector

  • Absorption correction: multi-scan (CrysAlis Pro; Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis Pro. Oxford Diffraction Ltd, Yarnton, Oxfordshire, England.]) Tmin = 0.431, Tmax = 1.000

  • 6248 measured reflections

  • 3344 independent reflections

  • 2761 reflections with I > 2σ(I)

  • Rint = 0.021
Refinement

  • R[F2 > 2σ(F2)] = 0.041

  • wR(F2) = 0.118

  • S = 1.07

  • 3344 reflections

  • 272 parameters

  • H-atom parameters constrained

  • Δρmax = 0.27 e Å−3

  • Δρmin = −0.29 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
N2A—H2AA⋯O22Bi 0.88 2.20 3.0737 (18) 171
N3A—H3AB⋯O1B 0.88 2.03 2.7866 (18) 143
N3A—H3AB⋯O62B 0.88 2.35 3.0882 (18) 142
N3A—H3AC⋯O1Aii 0.88 2.32 2.9808 (19) 132
N4A—H4AA⋯O1B 0.88 1.98 2.7499 (18) 145
N4A—H4AA⋯O21B 0.88 2.34 3.0683 (19) 141
N4A—H4AB⋯O21Bi 0.88 2.11 2.9572 (18) 163
C3A—H3AA⋯O41Biii 0.95 2.37 3.262 (2) 155
C7A—H7AB⋯O1Biv 0.98 2.56 3.447 (2) 151
Symmetry codes: (i) -x+2, -y+2, -z+1; (ii) -x+1, -y+1, -z+2; (iii) -x+1, -y+2, -z+1; (iv) -x+2, -y+1, -z+1.

Data collection: CrysAlis Pro (Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis Pro. Oxford Diffraction Ltd, Yarnton, Oxfordshire, England.]); cell refinement: CrysAlis RED (Oxford Diffraction, 2007[Oxford Diffraction (2007). CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536809037647/kp2228sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536809037647/kp2228Isup2.hkl

checkCIF report


Comment top

Guanidines, important compounds that have many biological, chemical and medicinal applications (Berlinck, 2002; Heys et al., 2000), have received increasing interest as medicinal agents with antitumour, antihypertensive, antiglaucoma and cardiotonic activities (Laeckmann et al., 2002; Kelley et al., 2001; Moroni et al., 2001). Due to their strong basic character, they can be considered as super-bases that readily undergo protonation to generate resonance-stabilized guanidinium cations (Ishikawa & Isobe, 2002). Guanidine is used in variety of supramolecular recognition processes across the spectrum of organic, biological and medicinal chemistry (Orner & Hamilton, 2001) with special interest motivated by their potential applications in non-linear optics (Zyss et al., 1993).

The crystal structures of a few related guanidine derivatives viz. guanidinium 2-amino-4-nitrobenzoate monohydrate at 130 K (Smith et al., 2007), (2,4,6-trinitrophenyl)guanidine (Smith et al., 2007a), 4-methoxy-phenylguanidinium chloride (Ren et al., 2007), (E)-1-[(2-methoxyphenyl)methyleneamino]guanidinium chloride (Sonar et al., 2007), have been reported. 1-(2-methyl-5-nitrophenyl)guanidine is one of the starting compounds for the synthesis of the anticancer drug, imatinib. In connection with the importance of guanidine derivatives, the present paper reports the crystal structure of the title compound, (I), C14H13N7O9.

The title compound, (I), crystallizes as a salt with one independent cation–anion pair [C8H11O2N4+.C6H2N3O7-] in the asymmetric unit (Fig. 1). Bond lengths and angles can be regarded as normal (Cambridge Structural Database, Version 5.30, February, 2009; Allen, 2002, Mogul, Version 1.1.3; Bruno et al., 2004). In the cation, the angle between the dihedral planes of the guanidinium ion [(CH5N3)+] and the bonded 2-methyl-5-nitrophenyl group is 83.0 (7)°. All three nitrogen atoms (N2A, N3A & N4A) exhibit sp2 hybridization with a sum of angles around each atom of 360.0 (0)° resulting in a planar guanidinium ion group. The dihedral angle between the mean planes of the 5-nitro group and the benzyl ring is 5.0 (3)°. In the picrate anion, the mean plane of two o-NO2 and single p-NO2 groups are twisted by 14.6 (4)°, 16.6 (3)° and 5.6 (8)°, respectively, from the mean plane of the benzyl ring. The difference in the twist angles of the mean planes of the two o-NO2 groups can be attributed to an intermolecular hydrogen bonded interaction between the guanidinium ion of the cation with both of these groups (O21B—N2B—O22B & O61B—N6B—O62B) of the picrate anion, in which the O21B and O62B atoms form intermolecular "side" hydrogen bonds (N4A—H4AA···O21B & N3A—H3AB···O62B) with N4A and N3A from the guanidinium ion (Fig. 2, Table 1). N4A and N3A also both form intermolecular hydrogen bonds with the phenolate oxygen anion O1B (N4A—H4AA···O1B & N3A—H3AB···O1B), each creating a bifrucated (three-centre), N—H···(O,O) hydrogen bond. As a result, O1B and O21B act as the double acceptors. N4A and N3A form additional intermolecular hydrogen bonds with nearby O21B (N4A—H4AB···O21B) and O1A (N3A—H3AC···O1A) atoms, respectively. The dihedral angle between the mean planes of the benzyl ring and guanidinium ion group in the cation and the benzyl ring of the picrate anion are 80.8 (7)° and 7.4 (7)°, respectively. Additional weak N2A—H2AA···O22B and C3A—H3AA···O41B hydrogen bonds and π–π stacking interactions occur (Cg1···Cg1 = 3.693 (6) Å; -x, 1 - y, -z; slippage = 1.614°; Cg1 = C1A–C6A centroid) contributing to the stability of crystal packing.

A density functional theory (DFT) geometry optimization molecular orbital calculation (Schmidt & Polik, 2007) was performed on the C8H11O2N4+.C6H2N3O7- cation–anion pair of the title molecule, (I), with the GAUSSIAN03 program package (Frisch et al. 2004) employing the B3LYP (Becke three parameter Lee–Yang–Parr) exchange correlation functional, which combines the hybrid exchange functional of Becke (Becke, 1988, 1993) with the gradient-correlation functional of Lee, Yang and Parr (Lee et al. 1988) and the 3-21G basis set (Hehre et al. 1986). Starting geometries were taken from X-ray refinement data. The dihedral angle between the dihedral planes of the guanidinium ion [(CH5N3)+] and the bonded 2-methyl-5-nitrophenyl group in the cation decreases by 7.1 (2)° to 70.9 (1)° while the mean plane of the 5-nitro group decreases by 5.0 (3)° to become planar with the benzyl ring. In the picrate anion, the twist of the mean planes of two o-NO2 and single p-NO2 groups decreases by 12.3 (1)°, 10.4 (9)° and 5.6 (8)° to 4.3 (2)°, 4.1 (5)° and 0.0 (0)°, respectively, from the mean plane of the 6-membered benzyl ring. The dihedral angle between the mean planes of the benzyl ring and guanidinium ion group in the cation and the benzyl ring of the picrate anion change by -17.8 (5)° and +2.1 (9)° to 63.0 (2)° and 9.6 (6)°, respectively. Examination of the partial charges from the DFT geometry optimization indicate that H4AA (0.4.4384) is slightly more positive than H3A (0.402348) producing a slightly delocalized proton charge over the guanidium group and favoring the N4A atom. This coincides with a shorter N4A—H4AA···O1B (= 1.984 Å) hydrogen bond than N3A—H3A···O1B (= 2.033 Å) due to the multiple acceptor function of O1B. In conclusion, the significant number of conformational changes that are observed between the crystalline environment of this cation–anion (1-(2-methyl-5-nitrophenyl)guanidinium picrate) salt and that of a density functional theory calculation of the geometry optimized structure support the effects of strong intermolecular hydrogen bonding interactions and weak π–π ring intermolecular interactions between the guanidinium ion and bonded 2-methyl-5-nitrophenyl group of the cation and the o-NO2, p-NO2 and phenolate oxygen groups of the picrate anion as providing the major influence on packing effects in the crystal of the title compound, 1-(2-methyl-5-nitrophenyl)guanidinium picrate, (I).

Related literature top

For background literature, see: Berlinck (2002); Heys et al. (2000); Ishikawa & Isobe (2002); Kelley et al. (2001); Laeckmann et al. (2002); Moroni et al. (2001); Orner & Hamilton (2001); Zyss et al. (1993). For related structures, see: Cunningham et al. (1997); Demir et al. (2006); Gupta & Dutta (1975); Moghimi et al. (2005); Murtaza et al. (2007, 2009); Pereira Silva et al. (2007); Pruszynski et al. (1992); Ren et al. (2007); Sonar et al. (2007); Smith et al. (2007, 2007a); Stanford et al. (2007); Stępień & Grabowski (1977); Wang et al. (2009); Wei (2008). For density functional theory (DFT), see: Becke (1988, 1993); Frisch et al. (2004); Hehre et al. (1986); Lee et al. (1988); Schmidt & Polik (2007). For the Cambridge Structural Database, see: Allen (2002); Bruno et al. (2004).

Experimental top

The title compound was synthesized by adding a solution of picric acid (0.92 g, 2 mmol) in 10 ml of methanol to a solution of 1-(2-methyl-5-nitrophenyl)guanidine (0.45 g, 2 mmol) in 10 ml of methanol (Scheme 2). A yellow colour developed and the solution was allowed to evaporate slowly at room temperature.The yellow colour compound formed was filtered off, washed several times with diethyl ether, and then dried over CaCl2 (yield: 64.2%). Crystals for X-ray studies were grown by slow evaporation of dimethyl formamide solution. The melting range was found to be 382–385 K. Analysis found (calculated) for C14H13N7O9 (%): C: 39.95 (39.72), H: 2.99 (3.1), N: 23.36 (23.16).

Refinement top

All of the H atoms were placed in their calculated positions and then refined using the riding model with N—H = 0.88, C—H = 0.95 Å, and with Uiso(H) = 1.17–1.51Ueq(C,N).

Structure description top

Guanidines, important compounds that have many biological, chemical and medicinal applications (Berlinck, 2002; Heys et al., 2000), have received increasing interest as medicinal agents with antitumour, antihypertensive, antiglaucoma and cardiotonic activities (Laeckmann et al., 2002; Kelley et al., 2001; Moroni et al., 2001). Due to their strong basic character, they can be considered as super-bases that readily undergo protonation to generate resonance-stabilized guanidinium cations (Ishikawa & Isobe, 2002). Guanidine is used in variety of supramolecular recognition processes across the spectrum of organic, biological and medicinal chemistry (Orner & Hamilton, 2001) with special interest motivated by their potential applications in non-linear optics (Zyss et al., 1993).

The crystal structures of a few related guanidine derivatives viz. guanidinium 2-amino-4-nitrobenzoate monohydrate at 130 K (Smith et al., 2007), (2,4,6-trinitrophenyl)guanidine (Smith et al., 2007a), 4-methoxy-phenylguanidinium chloride (Ren et al., 2007), (E)-1-[(2-methoxyphenyl)methyleneamino]guanidinium chloride (Sonar et al., 2007), have been reported. 1-(2-methyl-5-nitrophenyl)guanidine is one of the starting compounds for the synthesis of the anticancer drug, imatinib. In connection with the importance of guanidine derivatives, the present paper reports the crystal structure of the title compound, (I), C14H13N7O9.

The title compound, (I), crystallizes as a salt with one independent cation–anion pair [C8H11O2N4+.C6H2N3O7-] in the asymmetric unit (Fig. 1). Bond lengths and angles can be regarded as normal (Cambridge Structural Database, Version 5.30, February, 2009; Allen, 2002, Mogul, Version 1.1.3; Bruno et al., 2004). In the cation, the angle between the dihedral planes of the guanidinium ion [(CH5N3)+] and the bonded 2-methyl-5-nitrophenyl group is 83.0 (7)°. All three nitrogen atoms (N2A, N3A & N4A) exhibit sp2 hybridization with a sum of angles around each atom of 360.0 (0)° resulting in a planar guanidinium ion group. The dihedral angle between the mean planes of the 5-nitro group and the benzyl ring is 5.0 (3)°. In the picrate anion, the mean plane of two o-NO2 and single p-NO2 groups are twisted by 14.6 (4)°, 16.6 (3)° and 5.6 (8)°, respectively, from the mean plane of the benzyl ring. The difference in the twist angles of the mean planes of the two o-NO2 groups can be attributed to an intermolecular hydrogen bonded interaction between the guanidinium ion of the cation with both of these groups (O21B—N2B—O22B & O61B—N6B—O62B) of the picrate anion, in which the O21B and O62B atoms form intermolecular "side" hydrogen bonds (N4A—H4AA···O21B & N3A—H3AB···O62B) with N4A and N3A from the guanidinium ion (Fig. 2, Table 1). N4A and N3A also both form intermolecular hydrogen bonds with the phenolate oxygen anion O1B (N4A—H4AA···O1B & N3A—H3AB···O1B), each creating a bifrucated (three-centre), N—H···(O,O) hydrogen bond. As a result, O1B and O21B act as the double acceptors. N4A and N3A form additional intermolecular hydrogen bonds with nearby O21B (N4A—H4AB···O21B) and O1A (N3A—H3AC···O1A) atoms, respectively. The dihedral angle between the mean planes of the benzyl ring and guanidinium ion group in the cation and the benzyl ring of the picrate anion are 80.8 (7)° and 7.4 (7)°, respectively. Additional weak N2A—H2AA···O22B and C3A—H3AA···O41B hydrogen bonds and π–π stacking interactions occur (Cg1···Cg1 = 3.693 (6) Å; -x, 1 - y, -z; slippage = 1.614°; Cg1 = C1A–C6A centroid) contributing to the stability of crystal packing.

A density functional theory (DFT) geometry optimization molecular orbital calculation (Schmidt & Polik, 2007) was performed on the C8H11O2N4+.C6H2N3O7- cation–anion pair of the title molecule, (I), with the GAUSSIAN03 program package (Frisch et al. 2004) employing the B3LYP (Becke three parameter Lee–Yang–Parr) exchange correlation functional, which combines the hybrid exchange functional of Becke (Becke, 1988, 1993) with the gradient-correlation functional of Lee, Yang and Parr (Lee et al. 1988) and the 3-21G basis set (Hehre et al. 1986). Starting geometries were taken from X-ray refinement data. The dihedral angle between the dihedral planes of the guanidinium ion [(CH5N3)+] and the bonded 2-methyl-5-nitrophenyl group in the cation decreases by 7.1 (2)° to 70.9 (1)° while the mean plane of the 5-nitro group decreases by 5.0 (3)° to become planar with the benzyl ring. In the picrate anion, the twist of the mean planes of two o-NO2 and single p-NO2 groups decreases by 12.3 (1)°, 10.4 (9)° and 5.6 (8)° to 4.3 (2)°, 4.1 (5)° and 0.0 (0)°, respectively, from the mean plane of the 6-membered benzyl ring. The dihedral angle between the mean planes of the benzyl ring and guanidinium ion group in the cation and the benzyl ring of the picrate anion change by -17.8 (5)° and +2.1 (9)° to 63.0 (2)° and 9.6 (6)°, respectively. Examination of the partial charges from the DFT geometry optimization indicate that H4AA (0.4.4384) is slightly more positive than H3A (0.402348) producing a slightly delocalized proton charge over the guanidium group and favoring the N4A atom. This coincides with a shorter N4A—H4AA···O1B (= 1.984 Å) hydrogen bond than N3A—H3A···O1B (= 2.033 Å) due to the multiple acceptor function of O1B. In conclusion, the significant number of conformational changes that are observed between the crystalline environment of this cation–anion (1-(2-methyl-5-nitrophenyl)guanidinium picrate) salt and that of a density functional theory calculation of the geometry optimized structure support the effects of strong intermolecular hydrogen bonding interactions and weak π–π ring intermolecular interactions between the guanidinium ion and bonded 2-methyl-5-nitrophenyl group of the cation and the o-NO2, p-NO2 and phenolate oxygen groups of the picrate anion as providing the major influence on packing effects in the crystal of the title compound, 1-(2-methyl-5-nitrophenyl)guanidinium picrate, (I).

For background literature, see: Berlinck (2002); Heys et al. (2000); Ishikawa & Isobe (2002); Kelley et al. (2001); Laeckmann et al. (2002); Moroni et al. (2001); Orner & Hamilton (2001); Zyss et al. (1993). For related structures, see: Cunningham et al. (1997); Demir et al. (2006); Gupta & Dutta (1975); Moghimi et al. (2005); Murtaza et al. (2007, 2009); Pereira Silva et al. (2007); Pruszynski et al. (1992); Ren et al. (2007); Sonar et al. (2007); Smith et al. (2007, 2007a); Stanford et al. (2007); Stępień & Grabowski (1977); Wang et al. (2009); Wei (2008). For density functional theory (DFT), see: Becke (1988, 1993); Frisch et al. (2004); Hehre et al. (1986); Lee et al. (1988); Schmidt & Polik (2007). For the Cambridge Structural Database, see: Allen (2002); Bruno et al. (2004).

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell refinement: CrysAlis RED (Oxford Diffraction, 2007); data reduction: CrysAlis RED (Oxford Diffraction, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The asymmetric unit of (I), showing the bifrucated (three-centre) N—H···(O,O) donor hydrogen bond configuration and the atom labeling scheme. Hydrogen bonds are shown as dashed lines. Displacement ellipsoids are shown at the 50% probability level.
[Figure 2] Fig. 2. Packing diagram of the title compound, (I), viewed down the b axis. Dashed lines indicate intermolecular bifurcated (three-centre) N—H···(O,O), N—H···O, and C—H···O donor hydrogen bond interactions which produces a 2-D network arranged along the (101) plane.
[Figure 3] Fig. 3. The formation of the title compound.
1-(2-methyl-5-nitrophenyl)guanidinium 2,4,6-trinitrophenolate top
Crystal data top
C8H11N4O2+·C6H2N3O7−Z = 2
Mr = 423.31F(000) = 436
Triclinic, P1Dx = 1.651 Mg m−3
Hall symbol: -P 1Cu Kα radiation, λ = 1.54184 Å
a = 7.1318 (10) ÅCell parameters from 3632 reflections
b = 10.6239 (13) Åθ = 4.3–73.8°
c = 11.9564 (13) ŵ = 1.23 mm−1
α = 84.257 (10)°T = 110 K
β = 74.497 (11)°Chunk, pale yellow
γ = 77.559 (11)°0.51 × 0.41 × 0.33 mm
V = 851.58 (18) Å3
Data collection top
Oxford Xcalibur
diffractometer with Ruby (Gemini Cu) detector		3344 independent reflections
Radiation source: Enhance (Cu) X-ray Source2761 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.021
Detector resolution: 10.5081 pixels mm-1θmax = 73.9°, θmin = 4.3°
ω scansh = −7→8
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2009)		k = −13→13
Tmin = 0.431, Tmax = 1.000l = −14→12
6248 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)] = 0.041Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.118H-atom parameters constrained
S = 1.07 w = 1/[σ2(Fo2) + (0.0696P)2 + 0.2349P]
where P = (Fo2 + 2Fc2)/3
3344 reflections(Δ/σ)max = 0.001
272 parametersΔρmax = 0.27 e Å−3
0 restraintsΔρmin = −0.29 e Å−3
Crystal data top
C8H11N4O2+·C6H2N3O7−γ = 77.559 (11)°
Mr = 423.31V = 851.58 (18) Å3
Triclinic, P1Z = 2
a = 7.1318 (10) ÅCu Kα radiation
b = 10.6239 (13) ŵ = 1.23 mm−1
c = 11.9564 (13) ÅT = 110 K
α = 84.257 (10)°0.51 × 0.41 × 0.33 mm
β = 74.497 (11)°
Data collection top
Oxford Xcalibur
diffractometer with Ruby (Gemini Cu) detector		3344 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2009)		2761 reflections with I > 2σ(I)
Tmin = 0.431, Tmax = 1.000Rint = 0.021
6248 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0410 restraints
wR(F2) = 0.118H-atom parameters constrained
S = 1.07Δρmax = 0.27 e Å−3
3344 reflectionsΔρmin = −0.29 e Å−3
272 parameters
Special details top

Experimental. CrysAlisPro, Oxford Diffraction Ltd., Version 1.171.33.34d (release 27-02-2009 CrysAlis171 .NET) (compiled Feb 27 2009,15:38:38) Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s 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
O1A0.6186 (2)0.42327 (13)1.18314 (12)0.0358 (3)
O2A0.5417 (2)0.62511 (13)1.13392 (12)0.0383 (3)
N1A0.6304 (2)0.51540 (14)1.11228 (13)0.0261 (3)
N2A0.9515 (2)0.68299 (13)0.73199 (12)0.0228 (3)
H2AA1.04520.72220.73760.027*
N3A0.7069 (2)0.67430 (13)0.64072 (12)0.0236 (3)
H3AB0.64160.70480.58770.028*
H3AC0.67620.60760.68650.028*
N4A0.8981 (2)0.82883 (13)0.58308 (12)0.0225 (3)
H4AA0.83360.86000.52990.027*
H4AB0.99430.86440.59090.027*
C1A1.0118 (2)0.44934 (16)0.77518 (15)0.0229 (3)
C2A0.9141 (2)0.57363 (15)0.80935 (14)0.0208 (3)
C3A0.7870 (2)0.59582 (16)0.91843 (14)0.0221 (3)
H3AA0.72040.68070.94000.026*
C4A0.7597 (2)0.49070 (16)0.99526 (14)0.0225 (3)
C5A0.8533 (2)0.36602 (16)0.96653 (15)0.0246 (4)
H5AA0.83270.29561.02080.029*
C6A0.9788 (3)0.34633 (16)0.85597 (15)0.0254 (4)
H6AA1.04370.26100.83470.030*
C7A1.1495 (3)0.42731 (18)0.65702 (16)0.0298 (4)
H7AA1.08240.47060.59790.045*
H7AB1.18800.33450.64450.045*
H7AC1.26820.46240.65130.045*
C8A0.8505 (2)0.72837 (15)0.65149 (14)0.0202 (3)
O1B0.59719 (17)0.85654 (11)0.47353 (10)0.0254 (3)
O21B0.84884 (19)1.00632 (12)0.36978 (12)0.0319 (3)
O22B0.7546 (2)1.15265 (12)0.24729 (12)0.0324 (3)
O41B0.3034 (2)1.09649 (12)0.03718 (11)0.0318 (3)
O42B0.1500 (3)0.93647 (15)0.08197 (15)0.0518 (5)
O61B0.2382 (2)0.64362 (13)0.39470 (12)0.0351 (3)
O62B0.3584 (2)0.69013 (14)0.52904 (12)0.0353 (3)
N2B0.7376 (2)1.05245 (13)0.30647 (12)0.0236 (3)
N4B0.2629 (2)1.00057 (14)0.09892 (13)0.0292 (3)
N6B0.3236 (2)0.71124 (14)0.43296 (12)0.0243 (3)
C1B0.5286 (2)0.88544 (15)0.38719 (14)0.0206 (3)
C2B0.5836 (2)0.98569 (15)0.29955 (14)0.0211 (3)
C3B0.4980 (2)1.02404 (16)0.20829 (14)0.0224 (3)
H3BA0.53641.09240.15550.027*
C4B0.3543 (3)0.96112 (16)0.19447 (14)0.0237 (3)
C5B0.3011 (2)0.85874 (16)0.26861 (14)0.0230 (3)
H5BA0.20800.81370.25540.028*
C6B0.3831 (2)0.82270 (15)0.36097 (14)0.0217 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O1A0.0411 (8)0.0400 (8)0.0270 (7)−0.0189 (6)−0.0048 (6)0.0092 (6)
O2A0.0393 (8)0.0368 (8)0.0319 (7)−0.0027 (6)−0.0007 (6)−0.0020 (6)
N1A0.0239 (7)0.0325 (8)0.0248 (7)−0.0119 (6)−0.0070 (6)0.0014 (6)
N2A0.0240 (7)0.0239 (7)0.0247 (7)−0.0118 (6)−0.0099 (6)0.0048 (6)
N3A0.0255 (7)0.0248 (7)0.0243 (7)−0.0104 (6)−0.0114 (6)0.0063 (5)
N4A0.0227 (7)0.0246 (7)0.0239 (7)−0.0101 (5)−0.0096 (6)0.0042 (5)
C1A0.0220 (8)0.0269 (8)0.0236 (8)−0.0084 (6)−0.0096 (6)−0.0005 (6)
C2A0.0211 (8)0.0240 (8)0.0216 (8)−0.0101 (6)−0.0099 (6)0.0036 (6)
C3A0.0206 (8)0.0227 (8)0.0262 (8)−0.0064 (6)−0.0103 (7)0.0003 (6)
C4A0.0214 (8)0.0284 (9)0.0211 (8)−0.0105 (6)−0.0076 (6)0.0013 (6)
C5A0.0277 (9)0.0238 (8)0.0275 (9)−0.0126 (7)−0.0121 (7)0.0048 (6)
C6A0.0286 (9)0.0212 (8)0.0298 (9)−0.0073 (7)−0.0115 (7)−0.0011 (7)
C7A0.0312 (9)0.0307 (9)0.0271 (9)−0.0075 (7)−0.0054 (7)−0.0024 (7)
C8A0.0195 (8)0.0207 (8)0.0193 (7)−0.0032 (6)−0.0031 (6)−0.0018 (6)
O1B0.0296 (6)0.0253 (6)0.0264 (6)−0.0099 (5)−0.0138 (5)0.0039 (5)
O21B0.0288 (7)0.0328 (7)0.0420 (7)−0.0141 (5)−0.0201 (6)0.0092 (6)
O22B0.0406 (7)0.0278 (7)0.0374 (7)−0.0190 (6)−0.0184 (6)0.0089 (5)
O41B0.0458 (8)0.0249 (6)0.0293 (7)−0.0084 (5)−0.0183 (6)0.0044 (5)
O42B0.0762 (11)0.0455 (9)0.0594 (10)−0.0350 (8)−0.0505 (9)0.0193 (8)
O61B0.0454 (8)0.0334 (7)0.0345 (7)−0.0234 (6)−0.0129 (6)0.0028 (5)
O62B0.0369 (7)0.0442 (8)0.0326 (7)−0.0218 (6)−0.0176 (6)0.0158 (6)
N2B0.0251 (7)0.0224 (7)0.0253 (7)−0.0087 (6)−0.0072 (6)0.0005 (5)
N4B0.0382 (8)0.0246 (8)0.0308 (8)−0.0088 (6)−0.0179 (7)0.0015 (6)
N6B0.0218 (7)0.0248 (7)0.0266 (7)−0.0076 (6)−0.0054 (6)0.0020 (6)
C1B0.0201 (8)0.0194 (7)0.0227 (8)−0.0032 (6)−0.0060 (6)−0.0024 (6)
C2B0.0209 (8)0.0203 (8)0.0237 (8)−0.0061 (6)−0.0062 (6)−0.0024 (6)
C3B0.0253 (8)0.0197 (8)0.0223 (8)−0.0052 (6)−0.0056 (6)−0.0015 (6)
C4B0.0281 (9)0.0242 (8)0.0224 (8)−0.0060 (7)−0.0116 (7)−0.0020 (6)
C5B0.0227 (8)0.0227 (8)0.0259 (8)−0.0066 (6)−0.0075 (7)−0.0034 (6)
C6B0.0209 (8)0.0213 (8)0.0233 (8)−0.0057 (6)−0.0055 (6)0.0001 (6)
Geometric parameters (Å, º) top
O1A—N1A1.2306 (19)C7A—H7AA0.9800
O2A—N1A1.217 (2)C7A—H7AB0.9800
N1A—C4A1.468 (2)C7A—H7AC0.9800
N2A—C8A1.344 (2)O1B—C1B1.241 (2)
N2A—C2A1.4363 (19)O21B—N2B1.2334 (18)
N2A—H2AA0.8800O22B—N2B1.2278 (18)
N3A—C8A1.317 (2)O41B—N4B1.2364 (19)
N3A—H3AB0.8800O42B—N4B1.227 (2)
N3A—H3AC0.8800O61B—N6B1.2250 (19)
N4A—C8A1.325 (2)O62B—N6B1.2280 (19)
N4A—H4AA0.8800N2B—C2B1.4534 (19)
N4A—H4AB0.8800N4B—C4B1.445 (2)
C1A—C2A1.398 (2)N6B—C6B1.463 (2)
C1A—C6A1.401 (2)C1B—C2B1.457 (2)
C1A—C7A1.497 (2)C1B—C6B1.460 (2)
C2A—C3A1.384 (2)C2B—C3B1.374 (2)
C3A—C4A1.386 (2)C3B—C4B1.390 (2)
C3A—H3AA0.9500C3B—H3BA0.9500
C4A—C5A1.381 (2)C4B—C5B1.385 (2)
C5A—C6A1.391 (2)C5B—C6B1.368 (2)
C5A—H5AA0.9500C5B—H5BA0.9500
C6A—H6AA0.9500
O2A—N1A—O1A123.73 (15)C1A—C7A—H7AC109.5
O2A—N1A—C4A118.54 (14)H7AA—C7A—H7AC109.5
O1A—N1A—C4A117.73 (15)H7AB—C7A—H7AC109.5
C8A—N2A—C2A123.28 (13)N3A—C8A—N4A120.59 (14)
C8A—N2A—H2AA118.4N3A—C8A—N2A120.75 (14)
C2A—N2A—H2AA118.4N4A—C8A—N2A118.67 (14)
C8A—N3A—H3AB120.0O22B—N2B—O21B122.00 (13)
C8A—N3A—H3AC120.0O22B—N2B—C2B118.56 (13)
H3AB—N3A—H3AC120.0O21B—N2B—C2B119.43 (13)
C8A—N4A—H4AA120.0O42B—N4B—O41B122.85 (15)
C8A—N4A—H4AB120.0O42B—N4B—C4B118.43 (14)
H4AA—N4A—H4AB120.0O41B—N4B—C4B118.72 (14)
C2A—C1A—C6A117.73 (16)O61B—N6B—O62B122.78 (14)
C2A—C1A—C7A121.12 (15)O61B—N6B—C6B117.97 (14)
C6A—C1A—C7A121.14 (16)O62B—N6B—C6B119.25 (13)
C3A—C2A—C1A121.89 (14)O1B—C1B—C2B124.20 (14)
C3A—C2A—N2A118.23 (15)O1B—C1B—C6B124.04 (15)
C1A—C2A—N2A119.82 (15)C2B—C1B—C6B111.76 (14)
C2A—C3A—C4A118.15 (15)C3B—C2B—N2B116.04 (14)
C2A—C3A—H3AA120.9C3B—C2B—C1B124.33 (14)
C4A—C3A—H3AA120.9N2B—C2B—C1B119.63 (14)
C5A—C4A—C3A122.45 (16)C2B—C3B—C4B118.92 (15)
C5A—C4A—N1A119.67 (14)C2B—C3B—H3BA120.5
C3A—C4A—N1A117.86 (15)C4B—C3B—H3BA120.5
C4A—C5A—C6A118.22 (15)C5B—C4B—C3B121.16 (15)
C4A—C5A—H5AA120.9C5B—C4B—N4B119.33 (14)
C6A—C5A—H5AA120.9C3B—C4B—N4B119.48 (14)
C5A—C6A—C1A121.56 (16)C6B—C5B—C4B119.76 (15)
C5A—C6A—H6AA119.2C6B—C5B—H5BA120.1
C1A—C6A—H6AA119.2C4B—C5B—H5BA120.1
C1A—C7A—H7AA109.5C5B—C6B—C1B123.85 (15)
C1A—C7A—H7AB109.5C5B—C6B—N6B116.32 (14)
H7AA—C7A—H7AB109.5C1B—C6B—N6B119.79 (14)
C6A—C1A—C2A—C3A−0.7 (2)O1B—C1B—C2B—C3B−175.27 (16)
C7A—C1A—C2A—C3A−179.70 (15)C6B—C1B—C2B—C3B4.9 (2)
C6A—C1A—C2A—N2A176.60 (13)O1B—C1B—C2B—N2B4.3 (3)
C7A—C1A—C2A—N2A−2.4 (2)C6B—C1B—C2B—N2B−175.56 (14)
C8A—N2A—C2A—C3A−94.78 (19)N2B—C2B—C3B—C4B177.91 (15)
C8A—N2A—C2A—C1A87.8 (2)C1B—C2B—C3B—C4B−2.5 (3)
C1A—C2A—C3A—C4A0.8 (2)C2B—C3B—C4B—C5B−2.0 (3)
N2A—C2A—C3A—C4A−176.51 (13)C2B—C3B—C4B—N4B179.95 (15)
C2A—C3A—C4A—C5A−0.3 (2)O42B—N4B—C4B—C5B−4.7 (3)
C2A—C3A—C4A—N1A177.78 (13)O41B—N4B—C4B—C5B176.06 (16)
O2A—N1A—C4A—C5A−176.41 (15)O42B—N4B—C4B—C3B173.45 (18)
O1A—N1A—C4A—C5A3.7 (2)O41B—N4B—C4B—C3B−5.8 (3)
O2A—N1A—C4A—C3A5.4 (2)C3B—C4B—C5B—C6B3.5 (3)
O1A—N1A—C4A—C3A−174.45 (14)N4B—C4B—C5B—C6B−178.40 (15)
C3A—C4A—C5A—C6A−0.3 (2)C4B—C5B—C6B—C1B−0.7 (3)
N1A—C4A—C5A—C6A−178.34 (14)C4B—C5B—C6B—N6B−178.21 (15)
C4A—C5A—C6A—C1A0.4 (2)O1B—C1B—C6B—C5B176.90 (16)
C2A—C1A—C6A—C5A0.1 (2)C2B—C1B—C6B—C5B−3.2 (2)
C7A—C1A—C6A—C5A179.07 (15)O1B—C1B—C6B—N6B−5.6 (2)
C2A—N2A—C8A—N3A1.0 (2)C2B—C1B—C6B—N6B174.21 (14)
C2A—N2A—C8A—N4A−179.04 (15)O61B—N6B—C6B—C5B13.8 (2)
O22B—N2B—C2B—C3B14.1 (2)O62B—N6B—C6B—C5B−165.22 (16)
O21B—N2B—C2B—C3B−164.83 (15)O61B—N6B—C6B—C1B−163.84 (16)
O22B—N2B—C2B—C1B−165.51 (15)O62B—N6B—C6B—C1B17.1 (2)
O21B—N2B—C2B—C1B15.6 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2A—H2AA···O22Bi0.882.203.0737 (18)171
N3A—H3AB···O1B0.882.032.7866 (18)143
N3A—H3AB···O62B0.882.353.0882 (18)142
N3A—H3AC···O1Aii0.882.322.9808 (19)132
N4A—H4AA···O1B0.881.982.7499 (18)145
N4A—H4AA···O21B0.882.343.0683 (19)141
N4A—H4AB···O21Bi0.882.112.9572 (18)163
C3A—H3AA···O41Biii0.952.373.262 (2)155
C7A—H7AB···O1Biv0.982.563.447 (2)151
Symmetry codes: (i) −x+2, −y+2, −z+1; (ii) −x+1, −y+1, −z+2; (iii) −x+1, −y+2, −z+1; (iv) −x+2, −y+1, −z+1.

Experimental details

Crystal data
Chemical formulaC8H11N4O2+·C6H2N3O7−
Mr423.31
Crystal system, space groupTriclinic, P1
Temperature (K)110
a, b, c (Å)7.1318 (10), 10.6239 (13), 11.9564 (13)
α, β, γ (°)84.257 (10), 74.497 (11), 77.559 (11)
V (Å3)851.58 (18)
Z2
Radiation typeCu Kα
µ (mm−1)1.23
Crystal size (mm)0.51 × 0.41 × 0.33
Data collection
DiffractometerOxford Xcalibur
diffractometer with Ruby (Gemini Cu) detector
Absorption correctionMulti-scan
(CrysAlis PRO; Oxford Diffraction, 2009)
Tmin, Tmax0.431, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections		6248, 3344, 2761
Rint0.021
(sin θ/λ)max (Å−1)0.623
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.041, 0.118, 1.07
No. of reflections3344
No. of parameters272
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.27, −0.29

Computer programs: CrysAlis PRO (Oxford Diffraction, 2009), CrysAlis RED (Oxford Diffraction, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2A—H2AA···O22Bi0.882.203.0737 (18)171.3
N3A—H3AB···O1B0.882.032.7866 (18)143.0
N3A—H3AB···O62B0.882.353.0882 (18)141.8
N3A—H3AC···O1Aii0.882.322.9808 (19)131.5
N4A—H4AA···O1B0.881.982.7499 (18)144.7
N4A—H4AA···O21B0.882.343.0683 (19)140.7
N4A—H4AB···O21Bi0.882.112.9572 (18)162.7
C3A—H3AA···O41Biii0.952.373.262 (2)155.3
C7A—H7AB···O1Biv0.982.563.447 (2)151.0
Symmetry codes: (i) −x+2, −y+2, −z+1; (ii) −x+1, −y+1, −z+2; (iii) −x+1, −y+2, −z+1; (iv) −x+2, −y+1, −z+1.
 

Acknowledgements

MTS thanks the University of Mysore for the use of their research facilities. RJB acknowledges the NSF MRI program (grant No. CHE-0619278) for funds to purchase the X-ray diffractometer.

References

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ISSN: 2056-9890
Volume 65| Part 11| November 2009| Pages o2788-o2789
https://doi.org/10.1107/S1600536809037647
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