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

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ISSN: 2056-9890

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

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[Gan, L. L., Cai, J. L. & Zhou, C. H. (2009a). Chin. Pharm. J. 44, 1361-1368.],b[Gan, L. L., Lu, Y. H. & Zhou, C. H. (2009b). Chin. J. Biochem. Pharm. 30, 127-131.]); Willems & Ilzerman (2010[Willems, L. I. & Ilzerman, A. P. (2010). Med. Chem. Res. 30, 778-817.]). For a related structure, see: Gowda et al. (2009[Gowda, B. T., Foro, S., Sowmya, B. P., Terao, H. & Fuess, H. (2009). Acta Cryst. E65, o389.]). For hydrogen-bond motifs, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]); Etter (1990[Etter, M. C. (1990). Acc. Chem. Res. 23, 120-126.]).

[Scheme 1]

Experimental

Crystal data
  • C10H20N4O3

  • Mr = 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)

  • Rint = 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

  • Δρmax = 0.21 e Å−3

  • Δρmin = −0.20 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA 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[Bruker (2004). SMART, SAINT-Plus and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT-Plus (Bruker, 2004[Bruker (2004). SMART, SAINT-Plus and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT-Plus and XPREP (Bruker, 2004[Bruker (2004). SMART, SAINT-Plus and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); 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: ORTEP-3 (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); software used to prepare material for publication: SHELXL97.

Supporting information


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.

Refinement top

The H atoms were positioned with idealized geometry using a riding model with C—H = 0.93 Å. All H atoms were refined with isotropic displacement parameters (set to 1.2 times of the Ueq of the parent atom).

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
[Figure 1] Fig. 1. Molecular Structure of the title compound, Showing the atom-labled Scheme.
[Figure 2] 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
C10H20N4O3F(000) = 264
Mr = 244.3prism
Triclinic, P1Dx = 1.269 Mg m3
Hall symbol: -P 1Melting point: 463 K
a = 8.1923 (17) ÅMo Kα radiation, λ = 0.71073 Å
b = 8.7859 (16) ÅCell parameters from 1632 reflections
c = 9.714 (2) Åθ = 25°
α = 109.451 (7)°µ = 0.10 mm1
β = 99.540 (7)°T = 300 K
γ = 96.474 (7)°Prism, colorless
V = 639.5 (2) Å30.22 × 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 tubeRint = 0.027
Graphite monochromatorθmax = 25.0°, θmin = 2.5°
multi–scanh = 99
6407 measured reflectionsk = 1010
2218 independent reflectionsl = 1111
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)] = 0.044Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.130H atoms treated by a mixture of independent and constrained refinement
S = 1.05 w = 1/[σ2(Fo2) + (0.0714P)2 + 0.0663P]
where P = (Fo2 + 2Fc2)/3
2218 reflections(Δ/σ)max < 0.001
162 parametersΔρmax = 0.21 e Å3
0 restraintsΔρmin = 0.20 e Å3
0 constraints
Crystal data top
C10H20N4O3γ = 96.474 (7)°
Mr = 244.3V = 639.5 (2) Å3
Triclinic, P1Z = 2
a = 8.1923 (17) ÅMo Kα radiation
b = 8.7859 (16) ŵ = 0.10 mm1
c = 9.714 (2) ÅT = 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 reflectionsRint = 0.027
2218 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0440 restraints
wR(F2) = 0.130H atoms treated by a mixture of independent and constrained refinement
S = 1.05Δρmax = 0.21 e Å3
2218 reflectionsΔρmin = 0.20 e Å3
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
xyzUiso*/Ueq
C80.0609 (3)0.4383 (3)0.7235 (3)0.0705 (7)
H8A0.15040.35920.72580.106*
H8B0.02750.46550.81070.106*
H8C0.01770.39310.63540.106*
C70.1275 (2)0.5921 (2)0.7215 (2)0.0452 (5)
O30.02502 (15)0.69800 (15)0.71797 (16)0.0449 (4)
C60.0186 (2)0.8470 (2)0.7099 (2)0.0363 (4)
N40.17149 (18)0.92339 (18)0.70828 (17)0.0379 (4)
C30.3293 (2)0.8718 (2)0.7533 (2)0.0386 (5)
H3A0.30940.75390.72910.046*
H3B0.37050.92410.86060.046*
C20.4601 (2)0.9178 (2)0.6738 (2)0.0426 (5)
H2A0.56520.88710.70810.051*
H2B0.4230.85740.56720.051*
N30.48827 (18)1.09515 (18)0.70205 (16)0.0380 (4)
C10.5834 (2)1.1978 (2)0.8426 (2)0.0372 (5)
C100.1871 (3)0.6755 (3)0.8630 (3)0.0710 (7)
H10A0.28580.60760.8660.106*
H10B0.21330.77960.8640.106*
H10C0.09990.69210.94860.106*
O20.10816 (16)0.90611 (16)0.70148 (16)0.0489 (4)
N20.7249 (2)1.1515 (2)0.8972 (2)0.0500 (5)
C50.3302 (2)1.1390 (2)0.6480 (2)0.0437 (5)
H5A0.29631.0830.54050.052*
H5B0.34811.25610.66820.052*
C40.1884 (2)1.0956 (2)0.7193 (2)0.0422 (5)
H4A0.21141.16660.82360.051*
H4B0.08351.11340.66930.051*
C90.2609 (3)0.5532 (3)0.5819 (3)0.0623 (6)
H9A0.35860.48460.58590.093*
H9B0.21850.49680.4960.093*
H9C0.29070.65330.57470.093*
O10.6559 (2)1.42316 (18)1.05009 (17)0.0655 (5)
H10.62361.50711.09510.098*
N10.5327 (2)1.33013 (19)0.91361 (19)0.0483 (5)
H2C0.776 (3)1.084 (3)0.835 (3)0.061 (7)*
H2D0.789 (3)1.232 (3)0.986 (3)0.076 (8)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C80.0538 (14)0.0579 (14)0.113 (2)0.0029 (12)0.0172 (14)0.0500 (15)
C70.0329 (10)0.0476 (12)0.0584 (13)0.0013 (9)0.0116 (9)0.0252 (10)
O30.0339 (7)0.0396 (8)0.0685 (9)0.0052 (6)0.0167 (7)0.0264 (7)
C60.0348 (10)0.0372 (10)0.0377 (10)0.0091 (8)0.0113 (8)0.0119 (8)
N40.0307 (8)0.0338 (8)0.0539 (10)0.0079 (6)0.0134 (7)0.0191 (7)
C30.0327 (10)0.0316 (10)0.0541 (12)0.0074 (8)0.0106 (9)0.0176 (9)
C20.0378 (11)0.0360 (10)0.0500 (12)0.0067 (8)0.0149 (9)0.0077 (9)
N30.0399 (9)0.0358 (9)0.0411 (9)0.0045 (7)0.0144 (7)0.0153 (7)
C10.0357 (10)0.0344 (10)0.0457 (11)0.0046 (8)0.0150 (9)0.0173 (9)
C100.0646 (15)0.0950 (19)0.0633 (15)0.0070 (14)0.0278 (13)0.0369 (14)
O20.0332 (8)0.0476 (8)0.0696 (10)0.0143 (6)0.0153 (7)0.0214 (7)
N20.0422 (10)0.0483 (11)0.0554 (12)0.0131 (9)0.0093 (9)0.0125 (9)
C50.0481 (12)0.0424 (11)0.0436 (11)0.0037 (9)0.0060 (9)0.0225 (9)
C40.0390 (11)0.0326 (10)0.0571 (12)0.0106 (8)0.0091 (9)0.0182 (9)
C90.0512 (13)0.0536 (13)0.0695 (16)0.0039 (11)0.0003 (12)0.0164 (12)
O10.0646 (10)0.0469 (9)0.0624 (10)0.0096 (8)0.0060 (8)0.0004 (7)
N10.0436 (10)0.0355 (9)0.0547 (11)0.0041 (8)0.0012 (8)0.0073 (8)
Geometric parameters (Å, º) top
C8—C71.517 (3)N3—C51.457 (2)
C8—H8A0.96C1—N11.292 (2)
C8—H8B0.96C1—N21.356 (3)
C8—H8C0.96C10—H10A0.96
C7—O31.484 (2)C10—H10B0.96
C7—C91.506 (3)C10—H10C0.96
C7—C101.515 (3)N2—H2C0.89 (3)
O3—C61.343 (2)N2—H2D0.94 (3)
C6—O21.216 (2)C5—C41.522 (3)
C6—N41.358 (2)C5—H5A0.97
N4—C31.465 (2)C5—H5B0.97
N4—C41.470 (2)C4—H4A0.97
C3—C21.514 (3)C4—H4B0.97
C3—H3A0.97C9—H9A0.96
C3—H3B0.97C9—H9B0.96
C2—N31.473 (2)C9—H9C0.96
C2—H2A0.97O1—N11.447 (2)
C2—H2B0.97O1—H10.82
N3—C11.398 (2)
C7—C8—H8A109.5C5—N3—C2108.79 (15)
C7—C8—H8B109.5N1—C1—N2123.51 (19)
H8A—C8—H8B109.5N1—C1—N3119.03 (17)
C7—C8—H8C109.5N2—C1—N3117.45 (17)
H8A—C8—H8C109.5C7—C10—H10A109.5
H8B—C8—H8C109.5C7—C10—H10B109.5
O3—C7—C9110.52 (16)H10A—C10—H10B109.5
O3—C7—C10109.00 (17)C7—C10—H10C109.5
C9—C7—C10112.76 (19)H10A—C10—H10C109.5
O3—C7—C8101.95 (15)H10B—C10—H10C109.5
C9—C7—C8110.19 (18)C1—N2—H2C119.9 (15)
C10—C7—C8111.90 (18)C1—N2—H2D112.7 (15)
C6—O3—C7121.19 (14)H2C—N2—H2D120 (2)
O2—C6—O3124.82 (16)N3—C5—C4113.42 (14)
O2—C6—N4123.46 (17)N3—C5—H5A108.9
O3—C6—N4111.70 (15)C4—C5—H5A108.9
C6—N4—C3123.10 (15)N3—C5—H5B108.9
C6—N4—C4117.64 (15)C4—C5—H5B108.9
C3—N4—C4115.06 (15)H5A—C5—H5B107.7
N4—C3—C2110.37 (15)N4—C4—C5110.69 (15)
N4—C3—H3A109.6N4—C4—H4A109.5
C2—C3—H3A109.6C5—C4—H4A109.5
N4—C3—H3B109.6N4—C4—H4B109.5
C2—C3—H3B109.6C5—C4—H4B109.5
H3A—C3—H3B108.1H4A—C4—H4B108.1
N3—C2—C3111.33 (14)C7—C9—H9A109.5
N3—C2—H2A109.4C7—C9—H9B109.5
C3—C2—H2A109.4H9A—C9—H9B109.5
N3—C2—H2B109.4C7—C9—H9C109.5
C3—C2—H2B109.4H9A—C9—H9C109.5
H2A—C2—H2B108H9B—C9—H9C109.5
C1—N3—C5117.38 (15)N1—O1—H1109.5
C1—N3—C2116.57 (15)C1—N1—O1109.58 (16)
C9—C7—O3—C660.5 (2)C3—C2—N3—C559.90 (19)
C10—C7—O3—C664.0 (2)C5—N3—C1—N13.9 (2)
C8—C7—O3—C6177.58 (17)C2—N3—C1—N1135.54 (18)
C7—O3—C6—O21.7 (3)C5—N3—C1—N2175.79 (15)
C7—O3—C6—N4179.86 (15)C2—N3—C1—N244.1 (2)
O2—C6—N4—C3165.07 (18)C1—N3—C5—C477.5 (2)
O3—C6—N4—C316.5 (2)C2—N3—C5—C457.6 (2)
O2—C6—N4—C49.3 (3)C6—N4—C4—C5154.43 (16)
O3—C6—N4—C4172.28 (15)C3—N4—C4—C547.9 (2)
C6—N4—C3—C2152.67 (16)N3—C5—C4—N451.3 (2)
C4—N4—C3—C251.0 (2)N2—C1—N1—O14.7 (3)
N4—C3—C2—N356.6 (2)N3—C1—N1—O1175.65 (15)
C3—C2—N3—C175.6 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2D···O10.94 (3)2.08 (3)2.538 (2)108.3 (19)
N2—H2C···O2i0.89 (3)2.10 (3)2.988 (2)173 (3)
O1—H1···N1ii0.822.042.764 (3)147
Symmetry codes: (i) x+1, y, z; (ii) x+1, y+3, z+2.

Experimental details

Crystal data
Chemical formulaC10H20N4O3
Mr244.3
Crystal system, space groupTriclinic, 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)
V3)639.5 (2)
Z2
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.22 × 0.16 × 0.1
Data collection
DiffractometerBruker SMART X2S
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
6407, 2218, 1632
Rint0.027
(sin θ/λ)max1)0.594
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.044, 0.130, 1.05
No. of reflections2218
No. of parameters162
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)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···AD—HH···AD···AD—H···A
N2—H2D···O10.94 (3)2.08 (3)2.538 (2)108.3 (19)
N2—H2C···O2i0.89 (3)2.10 (3)2.988 (2)173 (3)
O1—H1···N1ii0.822.042.764 (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.

References

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