(E)-tert-Butyl 4-(N′-hy­droxy­carbam­­imid­o­yl)piperazine-1-carboxyl­ate

Sreenivasa, S.; Manojkumar, K.E.; Suchetan, P.A.; Mohan, N.R.; Palakshamurthy, B.S.

doi:10.1107/S1600536812046223

organic compounds

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ISSN: 2056-9890

Volume 68| Part 12| December 2012| Page o3347

doi:10.1107/S1600536812046223

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(E)-tert-Butyl 4-(N′-hydroxycarbamimidoyl)piperazine-1-carboxylate

S. Sreenivasa,^a ^* K. E. Manojkumar,^a P. A. Suchetan,^b N. R. Mohan ^a and B. S. Palakshamurthy ^c

^aDepartment of Studies and Research in Chemistry, Tumkur University, Tumkur, Karnataka 572 103, India, ^bDepartment of Studies and Research in Chemistry, U.C.S, Tumkur University, Tumkur, Karnataka 572 103, India, and ^cDepartment of Studies and Research in Physics, U.C.S, Tumkur University, Tumkur, Karnataka 572 103, India
^*Correspondence e-mail: drsreenivasa@yahoo.co.in

(Received 14 October 2012; accepted 8 November 2012; online 14 November 2012)

In the title compound, C₁₀H₂₀N₄O₃, the piperazine ring adopts a chair conformation. The molecule adopts an E conformation across the C=N double bond, with the –OH group and the piperazine ring trans to one another. Further, the H atom of the hydroxy group is directed away from the NH₂ group. An intramolecular N—H⋯O contact occurs involving the NH₂ group and the oxime O atom. In the crystal, molecules are linked via strong N—H⋯O and O—H⋯N hydrogen bonds with alternating R₂²(6) and C(9) motifs into tetrameric units forming R₄⁴(28) motifs.

Related literature

For the synthesis, characterization and biological activity of piperazine and its derivatives, see: Gan et al. (2009a ,b ); Willems & Ilzerman (2010 ). For a related structure, see: Gowda et al. (2009 ). For hydrogen-bond motifs, see: Bernstein et al. (1995 ); Etter (1990 ).

Experimental

Crystal data

C₁₀H₂₀N₄O₃
M_r = 244.3
Triclinic, $[P \overline 1]$
a = 8.1923 (17) Å
b = 8.7859 (16) Å
c = 9.714 (2) Å
α = 109.451 (7)°
β = 99.540 (7)°
γ = 96.474 (7)°
V = 639.5 (2) Å³
Z = 2
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 300 K
0.22 × 0.16 × 0.1 mm

Data collection

Bruker SMART X2S diffractometer
6407 measured reflections
2218 independent reflections
1632 reflections with I > 2σ(I)
R_int = 0.027

Refinement

R[F² > 2σ(F²)] = 0.044
wR(F²) = 0.130
S = 1.05
2218 reflections
162 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.21 e Å⁻³
Δρ_min = −0.20 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2D⋯O1	0.94 (3)	2.08 (3)	2.538 (2)	108.3 (19)
N2—H2C⋯O2ⁱ	0.89 (3)	2.10 (3)	2.988 (2)	173 (3)
O1—H1⋯N1ⁱⁱ	0.82	2.04	2.764 (3)	147
Symmetry codes: (i) x+1, y, z; (ii) -x+1, -y+3, -z+2.

Data collection: SMART (Bruker, 2004 ); cell refinement: SAINT-Plus (Bruker, 2004); data reduction: SAINT-Plus and XPREP (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 2012 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812046223/zj2096sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812046223/zj2096Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812046223/zj2096Isup3.cml

checkCIF report

Comment top

Numerous piperazine derivatives like aryl amide, sulphonamides, Mannich bases, Schiff's bases, thiazolidinones, azetidinones, imidazolinones have shown a wide spectrum of biological activities viz. antiinflammatory, antibacterial, antimalarial, anticonvulsant, antipyretic, antitumor, anthelmintics, analgesic, antidepressant, antifungal, antitubercular, anticancer, antidiabetic etc. In this view, we synthesized the title compound to study its crystal structure. The molecule crystallizes in triclinic P-1 space group. The piperazine ring in the molecule adopts chair conformation and the molecule prefers E configuration across the C—N double bond, as the OH group and the piperazine ring are in the opposite side of the double bond (Figure 1). The hydrogen atom of the hydroxyl group is directed away from the NH₂ group. This results in stabilizing the structure through a strong intermolecular O—H···N(1) and an intramolecular N(2)—H···O hydrogen bonds. In addition to this, the molecule also exhibits a strong N(2)—H···O(C) intermolecular hydrogen bond. The molecules are connected through alternate R₂²(6) ring and C(9) chain hydrogen bond patterns into tetrameric units exhibiting R₄⁴(28) ring patterns (Figure 2). The average N—C bond length in the piperazine ring is 1.466 Å indicating the single bond nature. While, the N4—C(O) bond length is 1.359 (2) Å indicating the delocalization of the nitrogen lone pair of electrons into π system of the carbonyl group. The N(1)—C(1) bond length is 1.290 Å due to its double bond nature, but the N(3)—C(1) and N(2)—C(1) bond lengths are closer to N—C(O) lengths indicating the partial double bond nature of these bonds.

Related literature top

For the synthesis, characterization and biological activity of piperazine and its derivatives, see: Gan et al. ((2009a,b); Willems et al. (2010). For a related structure, see: Gowda et al. (2009). For hydrogen-bond motifs, see: Bernstein et al. (1995); Etter (1990).

Experimental top

To a solution of N-boc-piperazine (10.6 mmol) in 20 ml of acetonitrile was added cyanogen bromide (10.7 mmol) and K₂CO₃ (21.2 mmol) at -10°C. The reaction mixture was stirred for 18 h at room temperature under nitrogen atmosphere. N-Cyano-4-boc-piperazine was obtained. To N-cyano-4-boc-piperazine (4.6 mmol) in methanol was added NH₂OH.HCl (9.3 mmol) and stirred for 30 min at room temperature. The solvent was removed under reduced pressure and the crude product was washed with cold water and dried to yield white solid product. Single crystals employed in X-ray diffraction studies were obtained from slow evaporation of the solution of the compound in methanol.

Computing details top

Data collection: SMART (Bruker, 2004); cell refinement: SAINT-Plus (Bruker, 2004); data reduction: SAINT-Plus and XPREP (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 2012); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. Molecular Structure of the title compound, Showing the atom-labled Scheme.
	Fig. 2. Molecular packing of the title compound, Hydrogen bonds are shown in dashed lines.

(E)-tert-Butyl 4-(N'-hydroxycarbamimidoyl)piperazine-1-carboxylate top

Crystal data top

C₁₀H₂₀N₄O₃	F(000) = 264
M_r = 244.3	prism
Triclinic, P1	D_x = 1.269 Mg m⁻³
Hall symbol: -P 1	Melting point: 463 K
a = 8.1923 (17) Å	Mo Kα radiation, λ = 0.71073 Å
b = 8.7859 (16) Å	Cell parameters from 1632 reflections
c = 9.714 (2) Å	θ = 25°
α = 109.451 (7)°	µ = 0.10 mm⁻¹
β = 99.540 (7)°	T = 300 K
γ = 96.474 (7)°	Prism, colorless
V = 639.5 (2) Å³	0.22 × 0.16 × 0.1 mm
Z = 2

Data collection top

Bruker SMART X2S diffractometer	1632 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.027
Graphite monochromator	θ_max = 25.0°, θ_min = 2.5°
multi–scan	h = −9→9
6407 measured reflections	k = −10→10
2218 independent reflections	l = −11→11

Refinement top

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)] = 0.044	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.130	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	w = 1/[σ²(F_o²) + (0.0714P)² + 0.0663P] where P = (F_o² + 2F_c²)/3
2218 reflections	(Δ/σ)_max < 0.001
162 parameters	Δρ_max = 0.21 e Å⁻³
0 restraints	Δρ_min = −0.20 e Å⁻³
0 constraints

Crystal data top

C₁₀H₂₀N₄O₃	γ = 96.474 (7)°
M_r = 244.3	V = 639.5 (2) Å³
Triclinic, P1	Z = 2
a = 8.1923 (17) Å	Mo Kα radiation
b = 8.7859 (16) Å	µ = 0.10 mm⁻¹
c = 9.714 (2) Å	T = 300 K
α = 109.451 (7)°	0.22 × 0.16 × 0.1 mm
β = 99.540 (7)°

Data collection top

Bruker SMART X2S diffractometer	1632 reflections with I > 2σ(I)
6407 measured reflections	R_int = 0.027
2218 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.044	0 restraints
wR(F²) = 0.130	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	Δρ_max = 0.21 e Å⁻³
2218 reflections	Δρ_min = −0.20 e Å⁻³
162 parameters

Special details top

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

	x	y	z	U_iso*/U_eq
C8	−0.0609 (3)	0.4383 (3)	0.7235 (3)	0.0705 (7)
H8A	−0.1504	0.3592	0.7258	0.106*
H8B	0.0275	0.4655	0.8107	0.106*
H8C	−0.0177	0.3931	0.6354	0.106*
C7	−0.1275 (2)	0.5921 (2)	0.7215 (2)	0.0452 (5)
O3	0.02502 (15)	0.69800 (15)	0.71797 (16)	0.0449 (4)
C6	0.0186 (2)	0.8470 (2)	0.7099 (2)	0.0363 (4)
N4	0.17149 (18)	0.92339 (18)	0.70828 (17)	0.0379 (4)
C3	0.3293 (2)	0.8718 (2)	0.7533 (2)	0.0386 (5)
H3A	0.3094	0.7539	0.7291	0.046*
H3B	0.3705	0.9241	0.8606	0.046*
C2	0.4601 (2)	0.9178 (2)	0.6738 (2)	0.0426 (5)
H2A	0.5652	0.8871	0.7081	0.051*
H2B	0.423	0.8574	0.5672	0.051*
N3	0.48827 (18)	1.09515 (18)	0.70205 (16)	0.0380 (4)
C1	0.5834 (2)	1.1978 (2)	0.8426 (2)	0.0372 (5)
C10	−0.1871 (3)	0.6755 (3)	0.8630 (3)	0.0710 (7)
H10A	−0.2858	0.6076	0.866	0.106*
H10B	−0.2133	0.7796	0.864	0.106*
H10C	−0.0999	0.6921	0.9486	0.106*
O2	−0.10816 (16)	0.90611 (16)	0.70148 (16)	0.0489 (4)
N2	0.7249 (2)	1.1515 (2)	0.8972 (2)	0.0500 (5)
C5	0.3302 (2)	1.1390 (2)	0.6480 (2)	0.0437 (5)
H5A	0.2963	1.083	0.5405	0.052*
H5B	0.3481	1.2561	0.6682	0.052*
C4	0.1884 (2)	1.0956 (2)	0.7193 (2)	0.0422 (5)
H4A	0.2114	1.1666	0.8236	0.051*
H4B	0.0835	1.1134	0.6693	0.051*
C9	−0.2609 (3)	0.5532 (3)	0.5819 (3)	0.0623 (6)
H9A	−0.3586	0.4846	0.5859	0.093*
H9B	−0.2185	0.4968	0.496	0.093*
H9C	−0.2907	0.6533	0.5747	0.093*
O1	0.6559 (2)	1.42316 (18)	1.05009 (17)	0.0655 (5)
H1	0.6236	1.5071	1.0951	0.098*
N1	0.5327 (2)	1.33013 (19)	0.91361 (19)	0.0483 (5)
H2C	0.776 (3)	1.084 (3)	0.835 (3)	0.061 (7)*
H2D	0.789 (3)	1.232 (3)	0.986 (3)	0.076 (8)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C8	0.0538 (14)	0.0579 (14)	0.113 (2)	0.0029 (12)	0.0172 (14)	0.0500 (15)
C7	0.0329 (10)	0.0476 (12)	0.0584 (13)	−0.0013 (9)	0.0116 (9)	0.0252 (10)
O3	0.0339 (7)	0.0396 (8)	0.0685 (9)	0.0052 (6)	0.0167 (7)	0.0264 (7)
C6	0.0348 (10)	0.0372 (10)	0.0377 (10)	0.0091 (8)	0.0113 (8)	0.0119 (8)
N4	0.0307 (8)	0.0338 (8)	0.0539 (10)	0.0079 (6)	0.0134 (7)	0.0191 (7)
C3	0.0327 (10)	0.0316 (10)	0.0541 (12)	0.0074 (8)	0.0106 (9)	0.0176 (9)
C2	0.0378 (11)	0.0360 (10)	0.0500 (12)	0.0067 (8)	0.0149 (9)	0.0077 (9)
N3	0.0399 (9)	0.0358 (9)	0.0411 (9)	0.0045 (7)	0.0144 (7)	0.0153 (7)
C1	0.0357 (10)	0.0344 (10)	0.0457 (11)	0.0046 (8)	0.0150 (9)	0.0173 (9)
C10	0.0646 (15)	0.0950 (19)	0.0633 (15)	0.0070 (14)	0.0278 (13)	0.0369 (14)
O2	0.0332 (8)	0.0476 (8)	0.0696 (10)	0.0143 (6)	0.0153 (7)	0.0214 (7)
N2	0.0422 (10)	0.0483 (11)	0.0554 (12)	0.0131 (9)	0.0093 (9)	0.0125 (9)
C5	0.0481 (12)	0.0424 (11)	0.0436 (11)	0.0037 (9)	0.0060 (9)	0.0225 (9)
C4	0.0390 (11)	0.0326 (10)	0.0571 (12)	0.0106 (8)	0.0091 (9)	0.0182 (9)
C9	0.0512 (13)	0.0536 (13)	0.0695 (16)	−0.0039 (11)	0.0003 (12)	0.0164 (12)
O1	0.0646 (10)	0.0469 (9)	0.0624 (10)	0.0096 (8)	−0.0060 (8)	0.0004 (7)
N1	0.0436 (10)	0.0355 (9)	0.0547 (11)	0.0041 (8)	0.0012 (8)	0.0073 (8)

Geometric parameters (Å, º) top

C8—C7	1.517 (3)	N3—C5	1.457 (2)
C8—H8A	0.96	C1—N1	1.292 (2)
C8—H8B	0.96	C1—N2	1.356 (3)
C8—H8C	0.96	C10—H10A	0.96
C7—O3	1.484 (2)	C10—H10B	0.96
C7—C9	1.506 (3)	C10—H10C	0.96
C7—C10	1.515 (3)	N2—H2C	0.89 (3)
O3—C6	1.343 (2)	N2—H2D	0.94 (3)
C6—O2	1.216 (2)	C5—C4	1.522 (3)
C6—N4	1.358 (2)	C5—H5A	0.97
N4—C3	1.465 (2)	C5—H5B	0.97
N4—C4	1.470 (2)	C4—H4A	0.97
C3—C2	1.514 (3)	C4—H4B	0.97
C3—H3A	0.97	C9—H9A	0.96
C3—H3B	0.97	C9—H9B	0.96
C2—N3	1.473 (2)	C9—H9C	0.96
C2—H2A	0.97	O1—N1	1.447 (2)
C2—H2B	0.97	O1—H1	0.82
N3—C1	1.398 (2)

C7—C8—H8A	109.5	C5—N3—C2	108.79 (15)
C7—C8—H8B	109.5	N1—C1—N2	123.51 (19)
H8A—C8—H8B	109.5	N1—C1—N3	119.03 (17)
C7—C8—H8C	109.5	N2—C1—N3	117.45 (17)
H8A—C8—H8C	109.5	C7—C10—H10A	109.5
H8B—C8—H8C	109.5	C7—C10—H10B	109.5
O3—C7—C9	110.52 (16)	H10A—C10—H10B	109.5
O3—C7—C10	109.00 (17)	C7—C10—H10C	109.5
C9—C7—C10	112.76 (19)	H10A—C10—H10C	109.5
O3—C7—C8	101.95 (15)	H10B—C10—H10C	109.5
C9—C7—C8	110.19 (18)	C1—N2—H2C	119.9 (15)
C10—C7—C8	111.90 (18)	C1—N2—H2D	112.7 (15)
C6—O3—C7	121.19 (14)	H2C—N2—H2D	120 (2)
O2—C6—O3	124.82 (16)	N3—C5—C4	113.42 (14)
O2—C6—N4	123.46 (17)	N3—C5—H5A	108.9
O3—C6—N4	111.70 (15)	C4—C5—H5A	108.9
C6—N4—C3	123.10 (15)	N3—C5—H5B	108.9
C6—N4—C4	117.64 (15)	C4—C5—H5B	108.9
C3—N4—C4	115.06 (15)	H5A—C5—H5B	107.7
N4—C3—C2	110.37 (15)	N4—C4—C5	110.69 (15)
N4—C3—H3A	109.6	N4—C4—H4A	109.5
C2—C3—H3A	109.6	C5—C4—H4A	109.5
N4—C3—H3B	109.6	N4—C4—H4B	109.5
C2—C3—H3B	109.6	C5—C4—H4B	109.5
H3A—C3—H3B	108.1	H4A—C4—H4B	108.1
N3—C2—C3	111.33 (14)	C7—C9—H9A	109.5
N3—C2—H2A	109.4	C7—C9—H9B	109.5
C3—C2—H2A	109.4	H9A—C9—H9B	109.5
N3—C2—H2B	109.4	C7—C9—H9C	109.5
C3—C2—H2B	109.4	H9A—C9—H9C	109.5
H2A—C2—H2B	108	H9B—C9—H9C	109.5
C1—N3—C5	117.38 (15)	N1—O1—H1	109.5
C1—N3—C2	116.57 (15)	C1—N1—O1	109.58 (16)

C9—C7—O3—C6	60.5 (2)	C3—C2—N3—C5	−59.90 (19)
C10—C7—O3—C6	−64.0 (2)	C5—N3—C1—N1	−3.9 (2)
C8—C7—O3—C6	177.58 (17)	C2—N3—C1—N1	−135.54 (18)
C7—O3—C6—O2	−1.7 (3)	C5—N3—C1—N2	175.79 (15)
C7—O3—C6—N4	179.86 (15)	C2—N3—C1—N2	44.1 (2)
O2—C6—N4—C3	165.07 (18)	C1—N3—C5—C4	−77.5 (2)
O3—C6—N4—C3	−16.5 (2)	C2—N3—C5—C4	57.6 (2)
O2—C6—N4—C4	9.3 (3)	C6—N4—C4—C5	−154.43 (16)
O3—C6—N4—C4	−172.28 (15)	C3—N4—C4—C5	47.9 (2)
C6—N4—C3—C2	152.67 (16)	N3—C5—C4—N4	−51.3 (2)
C4—N4—C3—C2	−51.0 (2)	N2—C1—N1—O1	4.7 (3)
N4—C3—C2—N3	56.6 (2)	N3—C1—N1—O1	−175.65 (15)
C3—C2—N3—C1	75.6 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2D···O1	0.94 (3)	2.08 (3)	2.538 (2)	108.3 (19)
N2—H2C···O2ⁱ	0.89 (3)	2.10 (3)	2.988 (2)	173 (3)
O1—H1···N1ⁱⁱ	0.82	2.04	2.764 (3)	147

Symmetry codes: (i) x+1, y, z; (ii) −x+1, −y+3, −z+2.

Experimental details

Crystal data
Chemical formula	C₁₀H₂₀N₄O₃
M_r	244.3
Crystal system, space group	Triclinic, P1
Temperature (K)	300
a, b, c (Å)	8.1923 (17), 8.7859 (16), 9.714 (2)
α, β, γ (°)	109.451 (7), 99.540 (7), 96.474 (7)
V (Å³)	639.5 (2)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.22 × 0.16 × 0.1

Data collection
Diffractometer	Bruker SMART X2S diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	6407, 2218, 1632
R_int	0.027
(sin θ/λ)_max (Å⁻¹)	0.594

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.044, 0.130, 1.05
No. of reflections	2218
No. of parameters	162
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.21, −0.20

Computer programs: SMART (Bruker, 2004), SAINT-Plus (Bruker, 2004), SAINT-Plus and XPREP (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 2012).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2D···O1	0.94 (3)	2.08 (3)	2.538 (2)	108.3 (19)
N2—H2C···O2ⁱ	0.89 (3)	2.10 (3)	2.988 (2)	173 (3)
O1—H1···N1ⁱⁱ	0.82	2.04	2.764 (3)	147

Symmetry codes: (i) x+1, y, z; (ii) −x+1, −y+3, −z+2.

Acknowledgements

The authors thank Dr S. C. Sharma, Vice Chancellor, Tumkur University, Tumkur for his constant encouragement. and G. B. Sadananda, Department of Studies and Research in Physics, U. C. S. Tumkur University, Tumkur, for his help and valuable suggestions. BSPM thanks Dr H. C. Devarajegowda, Department of Physics Yuvarajas College (constituent), University of Mysore, for his guidance.

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