N-(1H-Indol-3-yl­methyl­idene)-4-methyl­piperazin-1-amine

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

doi:10.1107/S1600536813028523

organic compounds

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ISSN: 2056-9890

Volume 69| Part 11| November 2013| Page o1706

doi:10.1107/S1600536813028523

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N-(1H-Indol-3-ylmethylidene)-4-methylpiperazin-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 17 October 2013; online 26 October 2013)

In the title compound, C₁₄H₁₈N₄, the piperazine ring is in a slightly distorted chair conformation. The indole ring system is twisted from the piperazine ring, making a dihedral angle of 7.27 (11)°. In the crystal, N—H⋯N hydrogen bonds link molecules into chains along [10-1].

CCDC reference: 966906

Related literature

For a review of the current pharmacological and toxicological information for piperazine, see: Elliott (2011 ). For the biological activity of Schiff base ligands, see: Kharb et al. (2012 ); Savaliya et al. (2010 ); Xu et al. (2012 ). For related structures, see: Guo (2007 ); Ming-Lin et al. (2007 ); Xu et al. (2009 ); Zhou et al. (2011 ). For puckering parameters, see Cremer & Pople (1975 ). For standard bond lengths, see: Allen et al. (1987 ).

Experimental

Crystal data

C₁₄H₁₈N₄
M_r = 242.32
Monoclinic, P n
a = 7.5630 (5) Å
b = 6.5593 (4) Å
c = 13.2319 (9) Å
β = 100.072 (6)°
V = 646.29 (7) Å³
Z = 2
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 173 K
0.48 × 0.33 × 0.18 mm

Data collection

Agilent Gemini Eos diffractometer
Absorption correction: multi-scan CrysAlis PRO and CrysAlis RED, Agilent (2012 ). T_min = 0.868, T_max = 1.000
7074 measured reflections
3857 independent reflections
3214 reflections with I > 2σ(I)
R_int = 0.050

Refinement

R[F² > 2σ(F²)] = 0.058
wR(F²) = 0.163
S = 1.06
3857 reflections
165 parameters
2 restraints
H-atom parameters constrained
Δρ_max = 0.35 e Å⁻³
Δρ_min = −0.31 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N4—H4⋯N1ⁱ	0.88	2.29	2.947 (3)	131
Symmetry code: (i) $[x-{\script{1\over 2}}, -y+1, z+{\script{1\over 2}}]$ .

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: 966906

Crystal structure: contains datablock I. DOI: 10.1107/S1600536813028523/hg5354sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813028523/hg5354Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536813028523/hg5354Isup3.cml

checkCIF report

Comment top

The Schiff base ligands derived from 1-amino-4-methylpiperazine have attracted the interest due to diverse biological applications found with piperazine moiety. Schiff base piperazine derivatives were found to be designed for the study of their antimicrobial activity (Savaliya et al., 2010) and antibacterial activity (Xu et al., 2012). A valuable insight into recent advances on antimicrobial activity of piperazine derivatives is reported (Kharb et al., 2012). A review on the current pharmacological and toxicological information for piperazine derivatives is described (Elliott, 2011). The crystal structures of some related compounds, viz., 2-[(4-methyl piperazin-1-yl)iminomethyl]phenol (Guo, 2007), 1,4-bis{3-[4-(dimethy lamino)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), C₁₄H₁₈N₄, has been synthesized and the crystal structure is reported.

The title compound, (I), crystallizes with one independent molecule in the asymmetric unit (Fig .1). In the molecule, the piperazine ring is in a slightly disordered chair conformation (puckering parameters Q, θ, and ϕ = 0.568 (3)Å, 175.2 (3)° and 225 (3)°; Cremer & Pople, 1975). The indole ring is twisted from the piperazine ring with a N2/N3/C5/C6 torsion angle of -172.3 (2)°. Bond lengths are in normal ranges (Allen et al., 1987). N—H···N intermolecular hydrogen bonds (Table 1) are observed which link the molecules into chains along [1 0 -1] and influence crystal packing (Fig. 2).

Related literature top

For a review of the current pharmacological and toxicological information for piperazine, see: Elliott (2011). For the biological activity of Schiff base ligands, see: Kharb et al. (2012); Savaliya et al. (2010); Xu et al. (2012). For related structures, see: Guo (2007); Ming-Lin et al. (2007); Xu et al. (2009); 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 indole-3-carboxaldehyde (0.75 g, 0.005 mol) in a mixture of 5 ml of methanol and 5 ml of dichloromethane, 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 eight hours to obtain a solution. The solution was evaporated to a small volume at room temperature and allowed to stand. The crystals were formed in one day (m.p.: 459-463 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) (C₁₄H₁₈N₄) showing the labeling scheme with 50% probability displacement ellipsoids.
	Fig. 2. Molecular packing for (I) viewed along the a axis. Dashed lines indicate N—H···N intermolecular hydrogen bonds linking the molecules into chains along [1 0 -1]. H atoms not involved in hydrogen bonding have been removed for clarity.

N-(1H-Indol-3-ylmethylidene)-4-methylpiperazin-1-amine top

Crystal data top

C₁₄H₁₈N₄	F(000) = 260
M_r = 242.32	D_x = 1.245 Mg m⁻³
Monoclinic, Pn	Mo Kα radiation, λ = 0.71073 Å
a = 7.5630 (5) Å	Cell parameters from 2079 reflections
b = 6.5593 (4) Å	θ = 3.4–33.0°
c = 13.2319 (9) Å	µ = 0.08 mm⁻¹
β = 100.072 (6)°	T = 173 K
V = 646.29 (7) Å³	Irregular, yellow
Z = 2	0.48 × 0.33 × 0.18 mm

Data collection top

Agilent Gemini Eos diffractometer	3857 independent reflections
Radiation source: Enhance (Mo) X-ray Source	3214 reflections with I > 2σ(I)
Detector resolution: 16.0416 pixels mm^-1	R_int = 0.050
ω scans	θ_max = 33.1°, θ_min = 3.4°
Absorption correction: multi-scan CrysAlis PRO and CrysAlis RED, Agilent (2012).	h = −9→11
T_min = 0.868, T_max = 1.000	k = −6→9
7074 measured reflections	l = −19→19

Refinement top

Refinement on F²	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.058	w = 1/[σ²(F_o²) + (0.0862P)²] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.163	(Δ/σ)_max < 0.001
S = 1.06	Δρ_max = 0.35 e Å⁻³
3857 reflections	Δρ_min = −0.31 e Å⁻³
165 parameters	Extinction correction: SHELXL2012 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
2 restraints	Extinction coefficient: 0.027 (9)
Primary atom site location: iterative

Crystal data top

C₁₄H₁₈N₄	V = 646.29 (7) Å³
M_r = 242.32	Z = 2
Monoclinic, Pn	Mo Kα radiation
a = 7.5630 (5) Å	µ = 0.08 mm⁻¹
b = 6.5593 (4) Å	T = 173 K
c = 13.2319 (9) Å	0.48 × 0.33 × 0.18 mm
β = 100.072 (6)°

Data collection top

Agilent Gemini Eos diffractometer	3857 independent reflections
Absorption correction: multi-scan CrysAlis PRO and CrysAlis RED, Agilent (2012).	3214 reflections with I > 2σ(I)
T_min = 0.868, T_max = 1.000	R_int = 0.050
7074 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.058	2 restraints
wR(F²) = 0.163	H-atom parameters constrained
S = 1.06	Δρ_max = 0.35 e Å⁻³
3857 reflections	Δρ_min = −0.31 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
N1	0.5403 (3)	1.0302 (3)	0.32552 (17)	0.0256 (4)
N2	0.4353 (3)	0.8708 (3)	0.50758 (17)	0.0256 (5)
N3	0.4539 (3)	0.7746 (4)	0.60330 (19)	0.0283 (5)
N4	0.3483 (3)	0.2381 (3)	0.8128 (2)	0.0289 (5)
H4	0.3168	0.1197	0.8355	0.035*
C1	0.5358 (4)	1.1586 (4)	0.4158 (2)	0.0262 (5)
H1A	0.4167	1.2248	0.4097	0.031*
H1B	0.6279	1.2668	0.4196	0.031*
C2	0.5711 (3)	1.0305 (4)	0.5122 (2)	0.0252 (5)
H2A	0.6918	0.9678	0.5194	0.030*
H2B	0.5686	1.1181	0.5728	0.030*
C3	0.4253 (4)	0.7427 (4)	0.4164 (2)	0.0270 (5)
H3A	0.3232	0.6470	0.4125	0.032*
H3B	0.5369	0.6615	0.4214	0.032*
C4	0.4012 (3)	0.8721 (4)	0.3205 (2)	0.0287 (5)
H4A	0.4052	0.7834	0.2604	0.034*
H4B	0.2816	0.9379	0.3108	0.034*
C5	0.4143 (4)	0.5839 (4)	0.6077 (2)	0.0271 (5)
H5	0.3872	0.5075	0.5459	0.032*
C6	0.4101 (4)	0.4842 (4)	0.7047 (2)	0.0268 (5)
C7	0.3487 (4)	0.2858 (4)	0.7119 (2)	0.0276 (5)
H7	0.3125	0.1967	0.6555	0.033*
C8	0.4050 (3)	0.4047 (4)	0.8729 (2)	0.0256 (5)
C9	0.4229 (4)	0.4299 (5)	0.9786 (2)	0.0329 (6)
H9	0.3953	0.3224	1.0214	0.039*
C10	0.4827 (4)	0.6176 (5)	1.0192 (2)	0.0368 (6)
H10	0.4946	0.6398	1.0910	0.044*
C11	0.5260 (4)	0.7757 (5)	0.9559 (2)	0.0358 (7)
H11	0.5679	0.9023	0.9858	0.043*
C12	0.5083 (4)	0.7494 (4)	0.8510 (3)	0.0302 (6)
H12	0.5377	0.8569	0.8088	0.036*
C13	0.4467 (3)	0.5622 (4)	0.8078 (2)	0.0247 (5)
C14	0.5122 (4)	1.1517 (5)	0.2313 (2)	0.0363 (7)
H14A	0.3941	1.2173	0.2226	0.054*
H14B	0.5179	1.0628	0.1724	0.054*
H14C	0.6058	1.2563	0.2359	0.054*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0311 (10)	0.0236 (10)	0.0232 (10)	0.0024 (9)	0.0083 (8)	0.0033 (8)
N2	0.0341 (11)	0.0196 (9)	0.0250 (11)	−0.0007 (9)	0.0107 (8)	0.0011 (8)
N3	0.0346 (11)	0.0256 (11)	0.0272 (11)	0.0005 (9)	0.0121 (9)	0.0022 (9)
N4	0.0360 (12)	0.0201 (10)	0.0321 (12)	−0.0038 (9)	0.0098 (9)	0.0035 (9)
C1	0.0328 (12)	0.0182 (10)	0.0290 (13)	0.0009 (10)	0.0093 (10)	0.0015 (10)
C2	0.0313 (12)	0.0203 (11)	0.0256 (13)	−0.0021 (9)	0.0098 (9)	0.0002 (9)
C3	0.0328 (13)	0.0219 (11)	0.0269 (13)	−0.0018 (10)	0.0070 (10)	−0.0010 (10)
C4	0.0314 (12)	0.0290 (13)	0.0257 (13)	−0.0003 (10)	0.0052 (10)	−0.0005 (10)
C5	0.0332 (12)	0.0232 (12)	0.0271 (13)	−0.0017 (10)	0.0116 (10)	−0.0002 (10)
C6	0.0300 (12)	0.0224 (11)	0.0301 (13)	−0.0019 (9)	0.0112 (9)	0.0001 (10)
C7	0.0320 (12)	0.0223 (11)	0.0303 (14)	−0.0016 (10)	0.0101 (10)	0.0002 (10)
C8	0.0258 (11)	0.0207 (11)	0.0303 (13)	−0.0013 (10)	0.0048 (9)	0.0037 (10)
C9	0.0337 (13)	0.0340 (14)	0.0299 (14)	−0.0037 (12)	0.0026 (10)	0.0072 (12)
C10	0.0375 (15)	0.0410 (16)	0.0299 (15)	−0.0053 (13)	0.0002 (11)	0.0015 (12)
C11	0.0359 (15)	0.0325 (14)	0.0380 (17)	−0.0076 (12)	0.0040 (12)	−0.0043 (12)
C12	0.0268 (11)	0.0255 (12)	0.0388 (15)	−0.0048 (10)	0.0072 (10)	0.0011 (11)
C13	0.0217 (10)	0.0215 (11)	0.0318 (13)	0.0004 (9)	0.0073 (9)	0.0048 (10)
C14	0.0454 (16)	0.0343 (15)	0.0293 (14)	−0.0004 (13)	0.0069 (12)	0.0098 (12)

Geometric parameters (Å, º) top

N1—C1	1.467 (3)	C4—H4B	0.9900
N1—C4	1.470 (3)	C5—H5	0.9500
N1—C14	1.463 (4)	C5—C6	1.446 (4)
N2—N3	1.400 (3)	C6—C7	1.390 (4)
N2—C2	1.461 (3)	C6—C13	1.438 (4)
N2—C3	1.462 (3)	C7—H7	0.9500
N3—C5	1.289 (4)	C8—C9	1.392 (4)
N4—H4	0.8800	C8—C13	1.416 (4)
N4—C7	1.371 (4)	C9—H9	0.9500
N4—C8	1.375 (4)	C9—C10	1.387 (4)
C1—H1A	0.9900	C10—H10	0.9500
C1—H1B	0.9900	C10—C11	1.407 (5)
C1—C2	1.511 (4)	C11—H11	0.9500
C2—H2A	0.9900	C11—C12	1.382 (4)
C2—H2B	0.9900	C12—H12	0.9500
C3—H3A	0.9900	C12—C13	1.399 (4)
C3—H3B	0.9900	C14—H14A	0.9800
C3—C4	1.510 (4)	C14—H14B	0.9800
C4—H4A	0.9900	C14—H14C	0.9800

C1—N1—C4	108.8 (2)	N3—C5—H5	119.3
C14—N1—C1	111.1 (2)	N3—C5—C6	121.3 (3)
C14—N1—C4	110.5 (2)	C6—C5—H5	119.3
N3—N2—C2	109.1 (2)	C7—C6—C5	122.9 (3)
N3—N2—C3	118.0 (2)	C7—C6—C13	106.2 (2)
C2—N2—C3	112.4 (2)	C13—C6—C5	130.6 (2)
C5—N3—N2	119.4 (2)	N4—C7—C6	109.8 (2)
C7—N4—H4	125.4	N4—C7—H7	125.1
C7—N4—C8	109.1 (2)	C6—C7—H7	125.1
C8—N4—H4	125.4	N4—C8—C9	129.9 (3)
N1—C1—H1A	109.7	N4—C8—C13	108.0 (2)
N1—C1—H1B	109.7	C9—C8—C13	122.1 (3)
N1—C1—C2	110.0 (2)	C8—C9—H9	121.2
H1A—C1—H1B	108.2	C10—C9—C8	117.6 (3)
C2—C1—H1A	109.7	C10—C9—H9	121.2
C2—C1—H1B	109.7	C9—C10—H10	119.4
N2—C2—C1	110.1 (2)	C9—C10—C11	121.2 (3)
N2—C2—H2A	109.6	C11—C10—H10	119.4
N2—C2—H2B	109.6	C10—C11—H11	119.5
C1—C2—H2A	109.6	C12—C11—C10	120.9 (3)
C1—C2—H2B	109.6	C12—C11—H11	119.5
H2A—C2—H2B	108.2	C11—C12—H12	120.4
N2—C3—H3A	109.5	C11—C12—C13	119.1 (3)
N2—C3—H3B	109.5	C13—C12—H12	120.4
N2—C3—C4	110.6 (2)	C8—C13—C6	106.9 (2)
H3A—C3—H3B	108.1	C12—C13—C6	134.0 (3)
C4—C3—H3A	109.5	C12—C13—C8	119.1 (3)
C4—C3—H3B	109.5	N1—C14—H14A	109.5
N1—C4—C3	112.2 (2)	N1—C14—H14B	109.5
N1—C4—H4A	109.2	N1—C14—H14C	109.5
N1—C4—H4B	109.2	H14A—C14—H14B	109.5
C3—C4—H4A	109.2	H14A—C14—H14C	109.5
C3—C4—H4B	109.2	H14B—C14—H14C	109.5
H4A—C4—H4B	107.9

N1—C1—C2—N2	−59.6 (3)	C5—C6—C13—C12	−5.0 (5)
N2—N3—C5—C6	−172.3 (2)	C7—N4—C8—C9	178.7 (3)
N2—C3—C4—N1	54.1 (3)	C7—N4—C8—C13	−1.3 (3)
N3—N2—C2—C1	−171.0 (2)	C7—C6—C13—C8	0.0 (3)
N3—N2—C3—C4	178.7 (2)	C7—C6—C13—C12	−179.1 (3)
N3—C5—C6—C7	172.6 (3)	C8—N4—C7—C6	1.4 (3)
N3—C5—C6—C13	−0.8 (4)	C8—C9—C10—C11	−0.9 (4)
N4—C8—C9—C10	−179.5 (3)	C9—C8—C13—C6	−179.2 (2)
N4—C8—C13—C6	0.8 (3)	C9—C8—C13—C12	0.1 (4)
N4—C8—C13—C12	−179.9 (2)	C9—C10—C11—C12	0.7 (5)
C1—N1—C4—C3	−57.8 (3)	C10—C11—C12—C13	−0.1 (4)
C2—N2—N3—C5	−148.2 (2)	C11—C12—C13—C6	178.8 (3)
C2—N2—C3—C4	−53.0 (3)	C11—C12—C13—C8	−0.3 (4)
C3—N2—N3—C5	−18.4 (3)	C13—C6—C7—N4	−0.9 (3)
C3—N2—C2—C1	56.1 (3)	C13—C8—C9—C10	0.5 (4)
C4—N1—C1—C2	60.0 (3)	C14—N1—C1—C2	−178.1 (2)
C5—C6—C7—N4	−175.6 (2)	C14—N1—C4—C3	179.9 (2)
C5—C6—C13—C8	174.2 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N4—H4···N1ⁱ	0.88	2.29	2.947 (3)	131

Symmetry code: (i) x−1/2, −y+1, z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N4—H4···N1ⁱ	0.88	2.29	2.947 (3)	131.1

Symmetry code: (i) x−1/2, −y+1, z+1/2.

Acknowledgements

CNK thanks University of Mysore for research facilities and 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.

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