organic compounds
(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
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
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Data collection
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Refinement
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Data collection: SMART (Bruker, 2004); cell 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
10.1107/S1600536812046223/zj2096sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536812046223/zj2096Isup2.hkl
Supporting information file. DOI: 10.1107/S1600536812046223/zj2096Isup3.cml
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.
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).
Data collection: SMART (Bruker, 2004); cell
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).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. |
C10H20N4O3 | F(000) = 264 |
Mr = 244.3 | prism |
Triclinic, P1 | Dx = 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 |
Bruker SMART X2S diffractometer | 1632 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.027 |
Graphite monochromator | θmax = 25.0°, θmin = 2.5° |
multi–scan | h = −9→9 |
6407 measured reflections | k = −10→10 |
2218 independent reflections | l = −11→11 |
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(Fo2) + (0.0714P)2 + 0.0663P] where P = (Fo2 + 2Fc2)/3 |
2218 reflections | (Δ/σ)max < 0.001 |
162 parameters | Δρmax = 0.21 e Å−3 |
0 restraints | Δρmin = −0.20 e Å−3 |
0 constraints |
C10H20N4O3 | γ = 96.474 (7)° |
Mr = 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)° |
Bruker SMART X2S diffractometer | 1632 reflections with I > 2σ(I) |
6407 measured reflections | Rint = 0.027 |
2218 independent reflections |
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 | Δρmax = 0.21 e Å−3 |
2218 reflections | Δρmin = −0.20 e Å−3 |
162 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
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)* |
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) |
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) |
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 |
Mr | 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 |
Rint | 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 |
Δρmax, Δρmin (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).
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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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.