research communications
H-pyrazol-3-one
of 4-{[(cyanoimino)(methylsulfanyl)methyl]amino}-1,5-dimethyl-2-phenyl-2,3-dihydro-1aChemistry Department, Faculty of Science, Helwan University, Cairo, Egypt, bGreen Chemistry Department, National Research Center, Dokki, Cairo, Egypt, and cInstitut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Postfach 3329, D-38023 Braunschweig, Germany
*Correspondence e-mail: p.jones@tu-bs.de
In the title compound, C14H15N5OS, the tautomer present in the solid state is that in which the immediately exocyclic N atom bears the H atom. The central five-membered ring is almost planar (r.m.s. deviation = 0.025 Å), but both its N atoms are significantly pyramidalized. A classical hydrogen bond from the N—H group to the cyanide N atom forms inversion-symmetric dimers, which are further linked by C—H⋯O interactions.
Keywords: crystal structure; pyrazole; thiocarbamate; hydrogen bond.
CCDC reference: 1040102
1. Chemical context
The pyrazolone 4-amino-2,3-dimethyl-1-phenyl-3-pyrazolin-5-one (`4-aminoantipyrine') and its derivatives represent some of the most important compounds used as analgesic, antipyretic and anti-inflammatory drugs (Santos et al., 2010). The biological activity of these compounds has been attributed to their scavenging activity against reactive oxygen and nitrogen species in biochemical reactions (Costa et al., 2006). Continuing our interest in the synthesis of azoles and of fused azoles as both potential CNS regulants and antimetabolites in purine biochemical reactions (Elgemeie et al., 1997, 2004a,b, 2005, 2007, 2008), our current work deals with the synthesis and structure of methyl N-cyano-N-imidothiocarbamate derivatives of 4-aminoantipyrine derived from two-component reactions. The title compound (1) was synthesized by the condensation of 4-aminoantipyrine and N-cyanoimido-S,S-dimethyldithiocarbonate in a simple one-step reaction. Compound (1) can exist in two tautomeric forms: (1a) and (1b). The 1H and 13C NMR spectra cannot differentiate between the two structures. The X-ray was undertaken to establish the exact nature of the product.
2. Structural commentary
The molecule of (1) is shown in Fig. 1. The location and free of the NH hydrogen atom confirm the existence of the tautomer (1b) in the solid state. The central five-membered ring is effectively planar (r.m.s. deviation 0.025 Å), but both its nitrogen atoms are significantly pyramidalized, with C6 lying 0.635 (2) and C11 0.271 (2) Å out of the plane in opposite directions. The imidothiocarbamate group is also roughly planar (r.m.s.d. 0.05 Å) and almost perpendicular to the central ring [interplanar angle 83.38 (3)°]; the interplanar phenyl/dihydropyrazole angle is 44.82 (5)°.
3. Supramolecular features
The main intermolecular interaction is the classical hydrogen bond from the NH function N3—H03 to the cyanide nitrogen atom N5, forming inversion-symmetric dimers. These dimers are further linked in the a-axis direction by a pair of weak C—H⋯O hydrogen bonds to the same acceptor atom (C6—H6C⋯O1 and C16—H16⋯O1), forming a layer structure parallel to the ab plane (Fig. 2). See Table 1. The interaction C13—H13⋯N5 links the layers in the third dimension.
4. Database survey
The 1,5-dimethyl-2-phenyl-2,3-dihydro-1H-pyrazol-3-one ring system with a nitrogen substituent at the 4-position has been thoroughly investigated. A search of the Cambridge database (Version 5.35; Groom & Allen, 2014) gave 223 hits with 242 individual molecules, mean bond lengths N1—N2 1.405, N2—C3 1.394, C3—C4 1.439, C4—C5 1.364, N1—C5 1.372 Å; all of these values agree closely with the bond lengths observed in the title compound.
5. Synthesis and crystallization
A solution of N-cyanoimido-S,S-dimethyldithiocarbonate (0.01 mol) in ethanol (20 ml) was added to a solution of 4-aminoantipyrine (0.01 mol) in ethanol (30 ml) containing catalytic amounts of piperidine (0.5 ml). The reaction mixture was heated at reflux for 30 min and then evaporated under reduced pressure. The yellow solid product was collected by filtration and recrystallized from ethanol, yield 85%, m.p. 489–491 K.
6. Refinement
Crystal data, data collection and structure . The NH hydrogen atom was refined freely. Methyls were refined as idealized rigid groups that were allowed to rotate but not tip. Other H atoms were included using a riding model starting from calculated positions.
details are summarized in Table 2Supporting information
CCDC reference: 1040102
https://doi.org/10.1107/S2056989014027601/pk2542sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989014027601/pk2542Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2056989014027601/pk2542Isup3.cml
Data collection: CrysAlis PRO (Agilent, 2014); cell
CrysAlis PRO (Agilent, 2014); data reduction: CrysAlis PRO (Agilent, 2014); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).C14H15N5OS | F(000) = 632 |
Mr = 301.37 | Dx = 1.388 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 11166 reflections |
a = 7.3620 (2) Å | θ = 2.9–30.8° |
b = 11.9369 (4) Å | µ = 0.23 mm−1 |
c = 16.6755 (5) Å | T = 100 K |
β = 100.191 (3)° | Tablet, yellow |
V = 1442.30 (8) Å3 | 0.40 × 0.35 × 0.12 mm |
Z = 4 |
Oxford Diffraction Xcalibur Eos diffractometer | 4359 independent reflections |
Radiation source: Enhance (Mo) X-ray Source | 3829 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.033 |
Detector resolution: 16.1419 pixels mm-1 | θmax = 31.0°, θmin = 2.5° |
ω–scan | h = −10→10 |
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2014) | k = −16→17 |
Tmin = 0.913, Tmax = 0.973 | l = −23→24 |
37668 measured reflections |
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)] = 0.033 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.083 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.08 | w = 1/[σ2(Fo2) + (0.0355P)2 + 0.584P] where P = (Fo2 + 2Fc2)/3 |
4359 reflections | (Δ/σ)max = 0.001 |
197 parameters | Δρmax = 0.49 e Å−3 |
0 restraints | Δρmin = −0.28 e Å−3 |
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. Least-squares planes (x,y,z in crystal coordinates) and deviations from them (* indicates atom used to define plane) 5.7083 (0.0022) x + 6.9435 (0.0045) y + 1.7473 (0.0075) z = 5.2871 (0.0030) * 0.0075 (0.0007) C11 * -0.0046 (0.0008) C12 * -0.0024 (0.0008) C13 * 0.0067 (0.0008) C14 * -0.0038 (0.0008) C15 * -0.0032 (0.0008) C16 Rms deviation of fitted atoms = 0.0050 1.8491 (0.0035) x + 6.5323 (0.0049) y + 12.3627 (0.0056) z = 8.2341 (0.0008) Angle to previous plane (with approximate e.s.d.) = 44.82 (0.05) * -0.0339 (0.0006) N1 * 0.0321 (0.0006) N2 * -0.0180 (0.0006) C3 * -0.0029 (0.0006) C4 * 0.0226 (0.0006) C5 0.6346 (0.0017) C6 - 0.2707 (0.0016) C11 - 0.0906 (0.0015) O1 - 0.1072 (0.0016) N3 0.0915 (0.0018) C7 Rms deviation of fitted atoms = 0.0246 5.0497 (0.0013) x - 8.5455 (0.0018) y + 0.1177 (0.0066) z = 0.2502 (0.0039) Angle to previous plane (with approximate e.s.d.) = 83.38 (0.03) * -0.0121 (0.0005) N3 * 0.0218 (0.0008) C8 * 0.1054 (0.0008) N4 * 0.0159 (0.0008) C9 * -0.0687 (0.0007) N5 * -0.0211 (0.0005) S1 * -0.0412 (0.0005) C10 Rms deviation of fitted atoms = 0.0519 |
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. The NH hydrogen was refined freely. Methyls were refined as idealized rigid groups allowed to rotate but not tip. Other H were included using a riding model starting from calculated positions. |
x | y | z | Uiso*/Ueq | ||
S1 | 0.46361 (4) | 0.25628 (2) | 0.663545 (16) | 0.01610 (7) | |
O1 | 0.05702 (10) | 0.34546 (7) | 0.46766 (5) | 0.01656 (16) | |
N1 | 0.48581 (11) | 0.34600 (7) | 0.40783 (5) | 0.01156 (16) | |
N2 | 0.31507 (11) | 0.39592 (7) | 0.41232 (5) | 0.01173 (16) | |
N3 | 0.28997 (12) | 0.15084 (7) | 0.53431 (5) | 0.01269 (17) | |
H03 | 0.205 (2) | 0.1073 (13) | 0.5091 (9) | 0.025 (4)* | |
N4 | 0.21528 (12) | 0.09469 (7) | 0.66041 (5) | 0.01476 (17) | |
N5 | −0.03210 (14) | −0.03206 (8) | 0.59200 (6) | 0.01949 (19) | |
C3 | 0.21686 (13) | 0.32907 (8) | 0.45828 (6) | 0.01160 (18) | |
C4 | 0.34313 (14) | 0.24011 (8) | 0.48763 (6) | 0.01152 (18) | |
C5 | 0.50320 (14) | 0.25429 (8) | 0.45825 (6) | 0.01172 (18) | |
C6 | 0.63812 (14) | 0.42144 (9) | 0.39925 (7) | 0.0161 (2) | |
H6A | 0.6430 | 0.4829 | 0.4385 | 0.024* | |
H6B | 0.6186 | 0.4520 | 0.3438 | 0.024* | |
H6C | 0.7547 | 0.3799 | 0.4097 | 0.024* | |
C7 | 0.67468 (15) | 0.18602 (9) | 0.47425 (7) | 0.0190 (2) | |
H7A | 0.6539 | 0.1193 | 0.5056 | 0.029* | |
H7B | 0.7749 | 0.2306 | 0.5053 | 0.029* | |
H7C | 0.7083 | 0.1632 | 0.4224 | 0.029* | |
C8 | 0.30606 (14) | 0.15750 (8) | 0.61605 (6) | 0.01240 (18) | |
C9 | 0.08493 (14) | 0.02760 (9) | 0.62107 (6) | 0.01450 (19) | |
C10 | 0.43222 (16) | 0.24152 (10) | 0.76777 (6) | 0.0194 (2) | |
H10A | 0.3071 | 0.2651 | 0.7726 | 0.029* | |
H10B | 0.5223 | 0.2884 | 0.8030 | 0.029* | |
H10C | 0.4502 | 0.1630 | 0.7845 | 0.029* | |
C11 | 0.23608 (13) | 0.47889 (8) | 0.35581 (6) | 0.01204 (18) | |
C12 | 0.26102 (14) | 0.47700 (9) | 0.27495 (6) | 0.0150 (2) | |
H12 | 0.3340 | 0.4203 | 0.2563 | 0.018* | |
C13 | 0.17747 (15) | 0.55933 (10) | 0.22197 (7) | 0.0192 (2) | |
H13 | 0.1938 | 0.5591 | 0.1667 | 0.023* | |
C14 | 0.07053 (16) | 0.64172 (10) | 0.24912 (7) | 0.0215 (2) | |
H14 | 0.0152 | 0.6983 | 0.2127 | 0.026* | |
C15 | 0.04415 (15) | 0.64168 (10) | 0.32949 (7) | 0.0197 (2) | |
H15 | −0.0308 | 0.6976 | 0.3477 | 0.024* | |
C16 | 0.12666 (14) | 0.56035 (9) | 0.38346 (6) | 0.0153 (2) | |
H16 | 0.1087 | 0.5603 | 0.4385 | 0.018* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S1 | 0.01678 (13) | 0.01752 (13) | 0.01357 (12) | −0.00532 (9) | 0.00148 (9) | 0.00014 (9) |
O1 | 0.0108 (3) | 0.0214 (4) | 0.0189 (4) | 0.0022 (3) | 0.0065 (3) | 0.0028 (3) |
N1 | 0.0086 (4) | 0.0125 (4) | 0.0142 (4) | 0.0021 (3) | 0.0038 (3) | 0.0015 (3) |
N2 | 0.0089 (4) | 0.0146 (4) | 0.0126 (4) | 0.0034 (3) | 0.0042 (3) | 0.0026 (3) |
N3 | 0.0138 (4) | 0.0112 (4) | 0.0131 (4) | −0.0028 (3) | 0.0023 (3) | 0.0005 (3) |
N4 | 0.0149 (4) | 0.0149 (4) | 0.0147 (4) | −0.0015 (3) | 0.0033 (3) | 0.0018 (3) |
N5 | 0.0216 (5) | 0.0204 (5) | 0.0179 (4) | −0.0058 (4) | 0.0072 (4) | 0.0003 (3) |
C3 | 0.0116 (4) | 0.0131 (4) | 0.0102 (4) | −0.0005 (3) | 0.0024 (3) | −0.0003 (3) |
C4 | 0.0119 (4) | 0.0112 (4) | 0.0116 (4) | −0.0002 (3) | 0.0024 (3) | 0.0003 (3) |
C5 | 0.0115 (4) | 0.0114 (4) | 0.0123 (4) | 0.0010 (3) | 0.0019 (3) | −0.0008 (3) |
C6 | 0.0107 (4) | 0.0164 (5) | 0.0213 (5) | −0.0020 (4) | 0.0029 (4) | 0.0030 (4) |
C7 | 0.0140 (5) | 0.0173 (5) | 0.0263 (5) | 0.0054 (4) | 0.0052 (4) | 0.0054 (4) |
C8 | 0.0112 (4) | 0.0111 (4) | 0.0148 (4) | 0.0017 (3) | 0.0021 (3) | 0.0009 (3) |
C9 | 0.0168 (5) | 0.0143 (4) | 0.0141 (4) | 0.0009 (4) | 0.0072 (4) | 0.0028 (3) |
C10 | 0.0200 (5) | 0.0251 (6) | 0.0125 (5) | −0.0010 (4) | 0.0015 (4) | −0.0013 (4) |
C11 | 0.0099 (4) | 0.0133 (4) | 0.0127 (4) | 0.0003 (3) | 0.0014 (3) | 0.0021 (3) |
C12 | 0.0119 (4) | 0.0197 (5) | 0.0140 (4) | 0.0006 (4) | 0.0038 (4) | 0.0008 (4) |
C13 | 0.0156 (5) | 0.0285 (6) | 0.0137 (5) | 0.0001 (4) | 0.0027 (4) | 0.0060 (4) |
C14 | 0.0164 (5) | 0.0252 (6) | 0.0226 (5) | 0.0040 (4) | 0.0024 (4) | 0.0118 (4) |
C15 | 0.0171 (5) | 0.0181 (5) | 0.0245 (6) | 0.0067 (4) | 0.0051 (4) | 0.0047 (4) |
C16 | 0.0149 (5) | 0.0165 (5) | 0.0151 (5) | 0.0032 (4) | 0.0043 (4) | 0.0014 (4) |
S1—C8 | 1.7430 (10) | C13—C14 | 1.3850 (17) |
S1—C10 | 1.8021 (11) | C14—C15 | 1.3878 (16) |
O1—C3 | 1.2298 (12) | C15—C16 | 1.3884 (14) |
N1—C5 | 1.3725 (13) | N3—H03 | 0.861 (16) |
N1—N2 | 1.4051 (11) | C6—H6A | 0.9800 |
N1—C6 | 1.4647 (13) | C6—H6B | 0.9800 |
N2—C3 | 1.3938 (12) | C6—H6C | 0.9800 |
N2—C11 | 1.4189 (12) | C7—H7A | 0.9800 |
N3—C8 | 1.3495 (13) | C7—H7B | 0.9800 |
N3—C4 | 1.4150 (13) | C7—H7C | 0.9800 |
N4—C8 | 1.3157 (13) | C10—H10A | 0.9800 |
N4—C9 | 1.3303 (14) | C10—H10B | 0.9800 |
N5—C9 | 1.1562 (14) | C10—H10C | 0.9800 |
C3—C4 | 1.4389 (14) | C12—H12 | 0.9500 |
C4—C5 | 1.3644 (14) | C13—H13 | 0.9500 |
C5—C7 | 1.4866 (14) | C14—H14 | 0.9500 |
C11—C16 | 1.3923 (14) | C15—H15 | 0.9500 |
C11—C12 | 1.3928 (14) | C16—H16 | 0.9500 |
C12—C13 | 1.3901 (15) | ||
C8—S1—C10 | 100.58 (5) | C8—N3—H03 | 117.0 (10) |
C5—N1—N2 | 107.03 (8) | C4—N3—H03 | 115.6 (10) |
C5—N1—C6 | 124.07 (8) | N1—C6—H6A | 109.5 |
N2—N1—C6 | 116.87 (8) | N1—C6—H6B | 109.5 |
C3—N2—N1 | 110.03 (8) | H6A—C6—H6B | 109.5 |
C3—N2—C11 | 124.98 (8) | N1—C6—H6C | 109.5 |
N1—N2—C11 | 121.73 (8) | H6A—C6—H6C | 109.5 |
C8—N3—C4 | 121.86 (9) | H6B—C6—H6C | 109.5 |
C8—N4—C9 | 117.37 (9) | C5—C7—H7A | 109.5 |
O1—C3—N2 | 125.45 (9) | C5—C7—H7B | 109.5 |
O1—C3—C4 | 130.48 (9) | H7A—C7—H7B | 109.5 |
N2—C3—C4 | 104.05 (8) | C5—C7—H7C | 109.5 |
C5—C4—N3 | 129.16 (9) | H7A—C7—H7C | 109.5 |
C5—C4—C3 | 109.47 (9) | H7B—C7—H7C | 109.5 |
N3—C4—C3 | 121.20 (9) | S1—C10—H10A | 109.5 |
C4—C5—N1 | 109.03 (9) | S1—C10—H10B | 109.5 |
C4—C5—C7 | 128.87 (9) | H10A—C10—H10B | 109.5 |
N1—C5—C7 | 122.10 (9) | S1—C10—H10C | 109.5 |
N4—C8—N3 | 124.87 (9) | H10A—C10—H10C | 109.5 |
N4—C8—S1 | 119.57 (8) | H10B—C10—H10C | 109.5 |
N3—C8—S1 | 115.55 (8) | C13—C12—H12 | 120.5 |
N5—C9—N4 | 175.27 (11) | C11—C12—H12 | 120.5 |
C16—C11—C12 | 121.00 (9) | C14—C13—H13 | 119.8 |
C16—C11—N2 | 117.43 (9) | C12—C13—H13 | 119.8 |
C12—C11—N2 | 121.53 (9) | C13—C14—H14 | 120.0 |
C13—C12—C11 | 118.98 (10) | C15—C14—H14 | 120.0 |
C14—C13—C12 | 120.50 (10) | C14—C15—H15 | 119.8 |
C13—C14—C15 | 120.01 (10) | C16—C15—H15 | 119.8 |
C14—C15—C16 | 120.42 (10) | C15—C16—H16 | 120.5 |
C15—C16—C11 | 119.08 (10) | C11—C16—H16 | 120.5 |
C5—N1—N2—C3 | −6.47 (11) | N2—N1—C5—C7 | −174.80 (9) |
C6—N1—N2—C3 | −150.77 (9) | C6—N1—C5—C7 | −33.74 (15) |
C5—N1—N2—C11 | −167.02 (9) | C9—N4—C8—N3 | −7.03 (15) |
C6—N1—N2—C11 | 48.68 (12) | C9—N4—C8—S1 | 174.19 (8) |
N1—N2—C3—O1 | −173.69 (9) | C4—N3—C8—N4 | 159.83 (10) |
C11—N2—C3—O1 | −13.92 (16) | C4—N3—C8—S1 | −21.35 (13) |
N1—N2—C3—C4 | 4.76 (10) | C10—S1—C8—N4 | −3.77 (9) |
C11—N2—C3—C4 | 164.53 (9) | C10—S1—C8—N3 | 177.34 (8) |
C8—N3—C4—C5 | 98.29 (13) | C3—N2—C11—C16 | 53.45 (14) |
C8—N3—C4—C3 | −87.05 (12) | N1—N2—C11—C16 | −149.00 (9) |
O1—C3—C4—C5 | 176.99 (11) | C3—N2—C11—C12 | −124.26 (11) |
N2—C3—C4—C5 | −1.35 (11) | N1—N2—C11—C12 | 33.28 (14) |
O1—C3—C4—N3 | 1.38 (17) | C16—C11—C12—C13 | 1.19 (16) |
N2—C3—C4—N3 | −176.97 (9) | N2—C11—C12—C13 | 178.82 (10) |
N3—C4—C5—N1 | 172.55 (9) | C11—C12—C13—C14 | −0.23 (17) |
C3—C4—C5—N1 | −2.60 (11) | C12—C13—C14—C15 | −0.84 (18) |
N3—C4—C5—C7 | −7.13 (18) | C13—C14—C15—C16 | 0.97 (18) |
C3—C4—C5—C7 | 177.71 (10) | C14—C15—C16—C11 | −0.03 (17) |
N2—N1—C5—C4 | 5.49 (11) | C12—C11—C16—C15 | −1.06 (16) |
C6—N1—C5—C4 | 146.55 (9) | N2—C11—C16—C15 | −178.78 (10) |
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H03···N5i | 0.861 (16) | 2.125 (16) | 2.9386 (13) | 157.3 (14) |
C6—H6C···O1ii | 0.98 | 2.30 | 3.2233 (13) | 156 |
C16—H16···O1iii | 0.95 | 2.42 | 3.2318 (13) | 143 |
C13—H13···N5iv | 0.95 | 2.57 | 3.3189 (15) | 136 |
Symmetry codes: (i) −x, −y, −z+1; (ii) x+1, y, z; (iii) −x, −y+1, −z+1; (iv) x+1/2, −y+1/2, z−1/2. |
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