4-Methyl-N-(4-nitro­benzyl­idene)piperazin-1-amine

Kavitha, C.N.; Jasinski, J.P.; Anderson, B.J.; Yathirajan, H.S.; Kaur, M.

doi:10.1107/S1600536813028493

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 69| Part 11| November 2013| Pages o1687-o1688

doi:10.1107/S1600536813028493

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4-Methyl-N-(4-nitrobenzylidene)piperazin-1-amine

Channappa N. Kavitha,^a Jerry P. Jasinski,^b ^* Brian J. Anderson,^b H.S. Yathirajan ^a and Manpreet Kaur ^a

^aDepartment of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore 570 006, India, and ^bDepartment of Chemistry, Keene State College, 229 Main Street, Keene, NH 03435-2001, USA
^*Correspondence e-mail: jjasinski@keene.edu

(Received 16 October 2013; accepted 16 October 2013; online 23 October 2013)

In the title compound, C₁₂H₁₆N₄O₂, the piperazine ring is in a slightly distorted chair conformation. In the molecule, the mean plane of the nitro group is twisted by 8.0 (3)° from that of the benzene ring. Also, the mean plane of the 2-nitrobenzyl ring is twisted slightly from that of the piperazine ring, with an N—N=C—C torsion angle of −176.24 (11)°. In the crystal, pairs of weak C—H⋯O interactions link the molecules into dimers approximately along [010].

CCDC reference: 966842

Related literature

For the biological activity of Schiff base piperzine derivatives, see: Kharb et al. (2012 ); Savaliya et al. (2010 ); Xu et al. (2009 ); Zhou et al. (2011 ). For therapeutic areas related to piperazines as drug molecules, see: Bogatcheva et al. (2006 ); Brockunier et al. (2004 ); Cai et al. (2009 ); Choudhary et al. (2006 ); Upadhayaya et al. (2004 ). For a review of current pharmacological and toxicological information for piperazine derivatives, see: Elliott (2011 ). For the synthesis of related piperazine compounds and their medicinal and pharmaceutical activity, see: Capuano et al. (2002 ); Contreras et al. (2001 ). For related structures, see: Guo (2007 ); Ming-Lin et al. (2007 ); Xu et al. (2012 ); Zhou et al. (2011). For puckering parameters, see: Cremer & Pople (1975 ). For standard bond lengths, see: Allen et al. (1987 ).

Experimental

Crystal data

C₁₂H₁₆N₄O₂
M_r = 248.29
Monoclinic, C 2/c
a = 27.9353 (14) Å
b = 5.9247 (3) Å
c = 18.7763 (7) Å
β = 126.527 (3)°
V = 2497.2 (2) Å³
Z = 8
Cu Kα radiation
μ = 0.77 mm⁻¹
T = 173 K
0.38 × 0.32 × 0.22 mm

Data collection

Agilent Xcalibur (Eos, Gemini) diffractometer
Absorption correction: multi-scan (CrysAlis PRO and CrysAlis RED; Agilent, 2012 ) T_min = 0.868, T_max = 1.000
7200 measured reflections
2439 independent reflections
2022 reflections with I > 2σ(I)
R_int = 0.031

Refinement

R[F² > 2σ(F²)] = 0.041
wR(F²) = 0.119
S = 1.02
2439 reflections
165 parameters
H-atom parameters constrained
Δρ_max = 0.22 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
C2—H2B⋯O1ⁱ	0.99	2.47	3.4052 (19)	158
Symmetry code: (i) $[-x+{\script{3\over 2}}, -y+{\script{5\over 2}}, -z+2]$ .

Data collection: CrysAlis PRO (Agilent, 2012); cell refinement: CrysAlis PRO; data reduction: CrysAlis RED (Agilent, 2012); program(s) used to solve structure: SUPERFLIP (Palatinus & Chapuis, 2007 ); program(s) used to refine structure: SHELXL2012 (Sheldrick, 2008 ); molecular graphics: OLEX2 (Dolomanov et al., 2009 ); software used to prepare material for publication: OLEX2.

Supporting information

CCDC reference: 966842

Crystal structure: contains datablock I. DOI: 10.1107/S1600536813028493/zl2568sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813028493/zl2568Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536813028493/zl2568Isup3.cml

checkCIF report

Comment top

Schiff base ligands derived from 1-amino-4-methylpiperazine have attracted interest due to diverse biological activities associated with the piperazine moiety. Schiff base piperazine derivatives have been designed to study their antimicrobial (Savaliya et al., 2010; Kharb et al., 2012)) and antibacterial activity (Xu et al., 2012). In addition, many drugs contain a piperazine ring as part of their molecular structure (Cai et al., 2009). Piperazines are among the most important building blocks in today's drug discovery and are found in biologically active compounds across a number of different therapeutic areas (Brockunier et al., 2004; Bogatcheva et al., 2006) such as antifungal (Upadhayaya et al., 2004), anti-bacterial, antimalarial activity and as in antipsychotic agents (Choudhary et al., 2006). A review on the current pharmacological and toxicological information for piperazine derivatives has been recently presented (Elliott, 2011). The synthesis of related piperazine compounds and their medicinal and pharmaceutical activity have also been reported (Contreras et al., 2001; Capuano et al., 2002). The crystal structures of some related compounds, viz., 2-[(4-methylpiperazin-1-yl)iminomethyl]phenol (Guo, 2007), 1,4-bis{3-[4-(dimethylamino)benzylideneamino] propyl}piperazine (Xu et al., 2009), 2-methoxy-4-[(4-methylpiperazin-1-yl)- iminomethyl]phenol (Zhou et al., 2011) and 2,4-dibromo-6- [(4-methylpiperazin-1-yl)iminomethyl]phenol (Ming-Lin et al., 2007) have been reported. In view of the above importance of N-piperazinyl Schiff bases, the title compound, (I), C₁₂H₁₆N₄O₂ has been synthesized and the crystal structure is reported herin.

In the title compound, (I), the piperazine ring is in a slightly distorted chair conformation with puckering parameters Q, θ, and ϕ = 0.5646Å, 170.8 (5)° and 187.961 (8)° (Cremer & Pople, 1975) (Fig. 1). In the molecule, the mean plane of the nitro group is twisted by 8.0 (3)° from that of the phenyl ring. Also, the mean plane of the 2-nitrobenzyl ring is twisted slightly from that of the piperazine ring with an N1/N2/C5/C6 torsion angle of -176.24 (11)°. Bond lengths are in normal ranges (Allen et al., 1987). Weak C—H···O intermolecular interactions are observed which lead to formation of dimers approximately along [010] and influence crystal packing (Fig. 2).

Related literature top

For the biological activity of Schiff base piperzine derivatives, see: Kharb et al. (2012); Savaliya et al. (2010); Xu et al. (2009); Zhou et al. (2011). For therapeutic areas related to piperazines as drug molecules, see: Bogatcheva et al. (2006); Brockunier et al. (2004); Cai et al. (2009); Choudhary et al. (2006); Upadhayaya et al. (2004). For a review of current pharmacological and toxicological information for piperazine derivatives, see: Elliott (2011). For the synthesis of related piperazine compounds and their medicinal and pharmaceutical activity, see: Capuano et al. (2002); Contreras et al. (2001). For related structures, see: Guo (2007); Ming-Lin et al. (2007); Xu et al. (2012); Zhou et al. (2011). For puckering parameters, see: Cremer & Pople (1975). For standard bond lengths, see: Allen et al. (1987).

Experimental top

To a solution of o-nitrobenzaldehyde (0.75 g, 0.005 mol) in 10 ml of methanol, an equimolar amount of (1-amino-4-methyl)piperazine (0.57 g, 0.005 mol) is added dropwise with constant stirring. The mixture was refluxed for 8 hours to obtain an orange solution. The solution was evaporated to a small volume at room temperature and allowed to stand. Yellow crystals were formed in one day (m.p.: 358–360 K) and were used as such for x-ray diffraction studies.

Computing details top

Data collection: CrysAlis PRO (Agilent, 2012); cell refinement: CrysAlis PRO (Agilent, 2012); data reduction: CrysAlis RED (Agilent, 2012); program(s) used to solve structure: SUPERFLIP (Palatinus & Chapuis, 2007); program(s) used to refine structure: SHELXL2012 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

Figures top

	Fig. 1. ORTEP drawing of (I) (C₁₂H₁₆N₄O₂ ) showing the labeling scheme with 50% probability displacement ellipsoids.
	Fig. 2. Molecular packing for (I) viewed along the a axis. Dashed lines indicate weak C—H···O intermolecular intereactions linking the molecules into dimers along [0 1 0]. H atoms not involved in hydrogen bonding have been removed for clarity.

4-Methyl-N-(4-nitrobenzylidene)piperazin-1-amine top

Crystal data top

C₁₂H₁₆N₄O₂	F(000) = 1056
M_r = 248.29	D_x = 1.321 Mg m⁻³
Monoclinic, C2/c	Cu Kα radiation, λ = 1.54184 Å
a = 27.9353 (14) Å	Cell parameters from 2934 reflections
b = 5.9247 (3) Å	θ = 3.2–72.3°
c = 18.7763 (7) Å	µ = 0.77 mm⁻¹
β = 126.527 (3)°	T = 173 K
V = 2497.2 (2) Å³	Irregular, yellow
Z = 8	0.38 × 0.32 × 0.22 mm

Data collection top

Agilent Xcalibur (Eos, Gemini) diffractometer	2439 independent reflections
Radiation source: Enhance (Cu) X-ray Source	2022 reflections with I > 2σ(I)
Detector resolution: 16.0416 pixels mm^-1	R_int = 0.031
ω scans	θ_max = 72.3°, θ_min = 3.9°
Absorption correction: multi-scan (CrysAlis PRO and CrysAlis RED; Agilent, 2012)	h = −34→32
T_min = 0.868, T_max = 1.000	k = −7→7
7200 measured reflections	l = −15→22

Refinement top

Refinement on F²	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.041	w = 1/[σ²(F_o²) + (0.0636P)² + 0.9105P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.119	(Δ/σ)_max = 0.001
S = 1.02	Δρ_max = 0.22 e Å⁻³
2439 reflections	Δρ_min = −0.18 e Å⁻³
165 parameters	Extinction correction: SHELXL2012 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.00056 (10)
Primary atom site location: structure-invariant direct methods

Crystal data top

C₁₂H₁₆N₄O₂	V = 2497.2 (2) Å³
M_r = 248.29	Z = 8
Monoclinic, C2/c	Cu Kα radiation
a = 27.9353 (14) Å	µ = 0.77 mm⁻¹
b = 5.9247 (3) Å	T = 173 K
c = 18.7763 (7) Å	0.38 × 0.32 × 0.22 mm
β = 126.527 (3)°

Data collection top

Agilent Xcalibur (Eos, Gemini) diffractometer	2439 independent reflections
Absorption correction: multi-scan (CrysAlis PRO and CrysAlis RED; Agilent, 2012)	2022 reflections with I > 2σ(I)
T_min = 0.868, T_max = 1.000	R_int = 0.031
7200 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.041	0 restraints
wR(F²) = 0.119	H-atom parameters constrained
S = 1.02	Δρ_max = 0.22 e Å⁻³
2439 reflections	Δρ_min = −0.18 e Å⁻³
165 parameters

Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O1	0.93562 (6)	1.1504 (2)	1.26970 (8)	0.0636 (4)
O2	0.96924 (5)	0.8095 (2)	1.29508 (7)	0.0509 (3)
N1	0.60437 (5)	0.7685 (2)	0.55865 (7)	0.0301 (3)
N2	0.66959 (5)	0.80238 (19)	0.74619 (7)	0.0282 (3)
N3	0.71366 (5)	0.8675 (2)	0.83118 (7)	0.0290 (3)
N4	0.93437 (5)	0.9567 (3)	1.24576 (8)	0.0403 (3)
C1	0.58784 (6)	0.9349 (2)	0.59774 (9)	0.0328 (3)
H1A	0.5570	0.8709	0.6023	0.039*
H1B	0.5710	1.0702	0.5594	0.039*
C2	0.64208 (6)	1.0007 (2)	0.68894 (9)	0.0329 (3)
H2A	0.6714	1.0761	0.6836	0.039*
H2B	0.6302	1.1090	0.7160	0.039*
C3	0.68086 (6)	0.6183 (2)	0.70644 (9)	0.0311 (3)
H3A	0.6928	0.4816	0.7438	0.037*
H3B	0.7140	0.6601	0.7037	0.037*
C4	0.62582 (6)	0.5677 (2)	0.61410 (9)	0.0317 (3)
H4A	0.6352	0.4494	0.5868	0.038*
H4B	0.5941	0.5090	0.6177	0.038*
C5	0.75644 (6)	0.7311 (2)	0.88472 (8)	0.0290 (3)
H5	0.7586	0.5880	0.8640	0.035*
C6	0.80153 (6)	0.7948 (2)	0.97695 (9)	0.0282 (3)
C7	0.80100 (6)	1.0039 (2)	1.01127 (9)	0.0317 (3)
H7	0.7706	1.1101	0.9737	0.038*
C8	0.84416 (6)	1.0572 (3)	1.09893 (9)	0.0336 (3)
H8	0.8438	1.1991	1.1221	0.040*
C9	0.88821 (6)	0.8997 (3)	1.15268 (9)	0.0326 (3)
C10	0.89029 (6)	0.6922 (3)	1.12129 (9)	0.0344 (3)
H10	0.9208	0.5867	1.1594	0.041*
C11	0.84702 (6)	0.6411 (2)	1.03298 (9)	0.0330 (3)
H11	0.8482	0.4998	1.0101	0.040*
C12	0.55353 (7)	0.7136 (3)	0.46826 (9)	0.0387 (4)
H12A	0.5211	0.6537	0.4689	0.058*
H12B	0.5654	0.6002	0.4436	0.058*
H12C	0.5400	0.8502	0.4317	0.058*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0527 (8)	0.0698 (9)	0.0412 (7)	0.0008 (6)	0.0132 (6)	−0.0240 (6)
O2	0.0326 (6)	0.0792 (9)	0.0295 (6)	0.0096 (6)	0.0123 (5)	0.0014 (6)
N1	0.0278 (6)	0.0347 (6)	0.0256 (6)	−0.0026 (5)	0.0146 (5)	−0.0031 (5)
N2	0.0279 (6)	0.0289 (6)	0.0245 (6)	−0.0001 (4)	0.0138 (5)	−0.0035 (4)
N3	0.0278 (6)	0.0326 (6)	0.0257 (6)	−0.0038 (5)	0.0154 (5)	−0.0042 (4)
N4	0.0280 (6)	0.0624 (9)	0.0287 (6)	−0.0011 (6)	0.0159 (6)	−0.0066 (6)
C1	0.0290 (7)	0.0327 (7)	0.0301 (7)	0.0031 (5)	0.0140 (6)	−0.0005 (5)
C2	0.0335 (7)	0.0274 (7)	0.0310 (7)	0.0027 (5)	0.0156 (6)	−0.0022 (6)
C3	0.0312 (7)	0.0286 (7)	0.0284 (7)	0.0021 (5)	0.0150 (6)	−0.0031 (5)
C4	0.0334 (7)	0.0291 (7)	0.0302 (7)	−0.0029 (5)	0.0177 (6)	−0.0061 (5)
C5	0.0291 (7)	0.0304 (7)	0.0290 (7)	−0.0023 (5)	0.0181 (6)	−0.0026 (5)
C6	0.0271 (7)	0.0331 (7)	0.0278 (7)	−0.0036 (5)	0.0183 (6)	−0.0010 (5)
C7	0.0291 (7)	0.0354 (7)	0.0289 (7)	0.0009 (6)	0.0163 (6)	−0.0002 (6)
C8	0.0325 (7)	0.0365 (8)	0.0330 (7)	−0.0035 (6)	0.0202 (6)	−0.0065 (6)
C9	0.0261 (7)	0.0467 (8)	0.0264 (7)	−0.0050 (6)	0.0165 (6)	−0.0041 (6)
C10	0.0282 (7)	0.0437 (8)	0.0295 (7)	0.0037 (6)	0.0161 (6)	0.0037 (6)
C11	0.0325 (7)	0.0341 (7)	0.0334 (7)	0.0004 (6)	0.0201 (6)	−0.0018 (6)
C12	0.0333 (8)	0.0498 (9)	0.0265 (7)	−0.0039 (6)	0.0142 (6)	−0.0052 (6)

Geometric parameters (Å, º) top

O1—N4	1.2253 (19)	C4—H4A	0.9900
O2—N4	1.2219 (18)	C4—H4B	0.9900
N1—C1	1.4586 (17)	C5—H5	0.9500
N1—C4	1.4546 (18)	C5—C6	1.4598 (19)
N1—C12	1.4608 (17)	C6—C7	1.401 (2)
N2—N3	1.3682 (15)	C6—C11	1.400 (2)
N2—C2	1.4639 (17)	C7—H7	0.9500
N2—C3	1.4580 (16)	C7—C8	1.379 (2)
N3—C5	1.2889 (18)	C8—H8	0.9500
N4—C9	1.4657 (18)	C8—C9	1.388 (2)
C1—H1A	0.9900	C9—C10	1.379 (2)
C1—H1B	0.9900	C10—H10	0.9500
C1—C2	1.5137 (19)	C10—C11	1.384 (2)
C2—H2A	0.9900	C11—H11	0.9500
C2—H2B	0.9900	C12—H12A	0.9800
C3—H3A	0.9900	C12—H12B	0.9800
C3—H3B	0.9900	C12—H12C	0.9800
C3—C4	1.5122 (18)

C1—N1—C12	110.78 (11)	C3—C4—H4A	109.4
C4—N1—C1	108.16 (10)	C3—C4—H4B	109.4
C4—N1—C12	110.55 (11)	H4A—C4—H4B	108.0
N3—N2—C2	110.17 (10)	N3—C5—H5	119.7
N3—N2—C3	119.30 (10)	N3—C5—C6	120.54 (13)
C3—N2—C2	113.80 (10)	C6—C5—H5	119.7
C5—N3—N2	120.39 (12)	C7—C6—C5	122.44 (13)
O1—N4—C9	117.78 (14)	C11—C6—C5	118.67 (13)
O2—N4—O1	123.67 (13)	C11—C6—C7	118.89 (13)
O2—N4—C9	118.55 (14)	C6—C7—H7	119.6
N1—C1—H1A	109.7	C8—C7—C6	120.72 (14)
N1—C1—H1B	109.7	C8—C7—H7	119.6
N1—C1—C2	109.86 (11)	C7—C8—H8	120.6
H1A—C1—H1B	108.2	C7—C8—C9	118.76 (13)
C2—C1—H1A	109.7	C9—C8—H8	120.6
C2—C1—H1B	109.7	C8—C9—N4	118.83 (13)
N2—C2—C1	111.02 (11)	C10—C9—N4	118.94 (13)
N2—C2—H2A	109.4	C10—C9—C8	122.22 (13)
N2—C2—H2B	109.4	C9—C10—H10	120.7
C1—C2—H2A	109.4	C9—C10—C11	118.56 (13)
C1—C2—H2B	109.4	C11—C10—H10	120.7
H2A—C2—H2B	108.0	C6—C11—H11	119.6
N2—C3—H3A	109.5	C10—C11—C6	120.84 (13)
N2—C3—H3B	109.5	C10—C11—H11	119.6
N2—C3—C4	110.69 (11)	N1—C12—H12A	109.5
H3A—C3—H3B	108.1	N1—C12—H12B	109.5
C4—C3—H3A	109.5	N1—C12—H12C	109.5
C4—C3—H3B	109.5	H12A—C12—H12B	109.5
N1—C4—C3	111.29 (11)	H12A—C12—H12C	109.5
N1—C4—H4A	109.4	H12B—C12—H12C	109.5
N1—C4—H4B	109.4

O1—N4—C9—C8	−7.5 (2)	C3—N2—N3—C5	−21.56 (18)
O1—N4—C9—C10	171.92 (14)	C3—N2—C2—C1	50.72 (15)
O2—N4—C9—C8	172.30 (13)	C4—N1—C1—C2	62.44 (14)
O2—N4—C9—C10	−8.2 (2)	C5—C6—C7—C8	179.56 (12)
N1—C1—C2—N2	−56.86 (15)	C5—C6—C11—C10	−179.02 (12)
N2—N3—C5—C6	−176.24 (11)	C6—C7—C8—C9	0.0 (2)
N2—C3—C4—N1	55.30 (15)	C7—C6—C11—C10	1.1 (2)
N3—N2—C2—C1	−172.24 (11)	C7—C8—C9—N4	179.59 (12)
N3—N2—C3—C4	177.74 (11)	C7—C8—C9—C10	0.1 (2)
N3—C5—C6—C7	−0.5 (2)	C8—C9—C10—C11	0.4 (2)
N3—C5—C6—C11	179.62 (12)	C9—C10—C11—C6	−1.0 (2)
N4—C9—C10—C11	−179.07 (12)	C11—C6—C7—C8	−0.6 (2)
C1—N1—C4—C3	−62.15 (14)	C12—N1—C1—C2	−176.25 (11)
C2—N2—N3—C5	−155.91 (12)	C12—N1—C4—C3	176.40 (11)
C2—N2—C3—C4	−49.44 (15)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2B···O1ⁱ	0.99	2.47	3.4052 (19)	158

Symmetry code: (i) −x+3/2, −y+5/2, −z+2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2B···O1ⁱ	0.99	2.47	3.4052 (19)	158.4

Symmetry code: (i) −x+3/2, −y+5/2, −z+2.

Acknowledgements

CNK thanks University of Mysore for research facilities and is also grateful to the Principal, Maharani's Science College for Women, Mysore, for giving permission to undertake research. JPJ acknowledges the NSF–MRI program (grant No. CHE-1039027) for funds to purchase the X-ray diffractometer.

References

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