organic compounds
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6-tert-Butyl-4-[(4-hydroxymethyl-2H-1,2,3-triazol-2-yl)methyl]-2H-chromen-2-one
aDepartment of Studies in Physics, Manasagangotri, University of Mysore, Mysore 570 006, India, and bDepartment of Chemistry, Central College Campus, Bangalore University, Bangalore 560 001, India
*Correspondence e-mail: mahendra@physics.uni-mysore.ac.in
In the title compound, C17H19N3O3, the triazole ring and the chromene ring system [maximum deviation = 0.018 (2) Å for the O atom] bridged via a methylene C atom, are inclined to one another by 73.2 (1)°. In the crystal, molecules are linked by O—H⋯N hydrogen bonds, forming zigzag chains along [001]. The chains are linked by C—H⋯O hydrogen bonds, forming layers parallel to (010), and these layers are linked by C—H⋯π and π–π interactions [intercentroid distance = 3.557 (1) Å], forming a three-dimensional newwork. The hydroxymethyl group at the 4-position of the triazole ring is disordered over two sets of sites, with a refined occupancy ratio of 0.418 (11):0.584 (11).
Keywords: crystal structure; chromones; triazole; hydrogen bonding; C—H⋯π interactions.
CCDC reference: 1509457
Structure description
Chromones are a group of natural and synthetic oxygen et al., 2015). and their derivatives have wide applications in a number of diverse areas. They are used in the pharmaceutical industry as precursor reagents in the synthesis of a number of synthetic anticoagulant pharmaceuticals (Bairagi et al., 2012), the most notable being warfarin (Holbrook et al., 2005). Modified are a type of vitamin K antagonist (Marongiu & Barcellona, 2015). are of great interest due to their biological properties (Lacy & O'Kennedy, 2004). In particular, their physiological, bacteriostatic and anti-tumour activity (Mustafa et al., 2011) makes these compounds attractive for further backbone derivatization and screening for their therapeutic properties. 2H-chromen-2-ones exhibit extensive natural occurrence and biocompatibility, and have been found to exhibit variety of biological activities (Naik et al., 2012).
having a high degree of chemical diversity that is frequently linked to a broad array of biological activities (GasparIn the molecular structure of the title compound (Fig. 1), the chromene unit (O16/C9—C15/C17/C18), as expected, is almost planar, with a maximum deviation of 0.018 (2) Å for the ring atom O16. The carbonyl O atom, O19, is displaced from the chromene mean plane by 0.059 (2) Å. The triazole (N1/N4/N5/C2/C3) and the chromene (O16/C9–C15/C17/C18) rings, bridged via a methylene C atom, C8, are inclined to one another by 73.2 (1)°. The intra-ring bond conformation between chromene and triazole moieties are also characterized by torsion angles of −72.6 (2)° (C9—C8—N1—N5) and 178.24 (18)° (C20—C12—C11—C10). The hydroxymethyl O atom is not coplanar with the triazole ring, as indicated by torsion angle C2—C3—C6B—O7B = −58 (2)°. One methyl unit of the tert-butyl group is almost coplanar with the chromene ring as suggested by the torsion angle C11—C12—C20—C23 = 5.2 (3)°, while the other two methyl groups are above and below the ring plane, with torsion angles C13—C12—C20—C21 and C13—C12—C20—C22, being 64.9 (2) and −54.7 (3)°, respectively.
In the crystal, molecules are are linked by an O—H⋯N hydrogen bond, forming chains along the c-axis direction (Table 1). The chains are linked by C—H⋯O hydrogen bonds, forming layers parallel to the ac plane (Table 1 and Fig. 2). Finally, the layers are linked by C—H⋯π and π–π interactions, forming a three-dimensional network (Table 1 and Fig. 2). The π–π interactions involve Cg1⋯Cg2i = Cg2⋯Cg1ii = 3.557 (1) Å [the two rings are inclined to one another by 14.95 (11)°, and the interplanar distances and slippages are 3.463 (1) and 1.545 Å, and 3.204 (1) and 0.812 Å, respectively; Cg1 and Cg2 are the centroids of rings N1/N4/N5/C2/C3 and O16/C9/C10/C15/C17/C18; symmetry codes: (i) −x + 1, −y + 1, z − and (ii) −x + 1, −y + 1, z + ].
Synthesis and crystallization
A mixture of propargyl alcohol (1.9 mmol), sodium azide (0.14 g, 2.0 mmol), copper(I) iodide (10 mol%) and triethylamine (0.19 g, 1.9 mmol) in 20 ml of acetone was taken in a round-bottom flask and stirred for 1 h. To this mixture, 4-bromomethylcoumarin (1.9 mmol) was added and the stirring continued for 8 h (the reaction was monitored by TLC). After the completion of the reaction, the catalyst was filtered through celite and the product was extracted with ether (3.10 ml). The solvent was removed under vacuum. The crude product was dried and recrystallized from ethyl acetate solution to give colourless block-like crystals of the title compound (yield 90%, m.p. 473–475 K). IR (KBr, cm−1): 1715 (lactone C=O), 3221 (OH). 1H NMR (400 MHz, CDC13): δ 1.28 (s, 9H, 3-CH3 of tert-butyl group), 1.70 (s, 1H, OH), 4.84 (s, 2H, –CH2O–), 5.77 (s, 2H, –CH2N–), 6.06 (s, 1H, C3—H), 7.31 (d, 1H, C7—H, J1,2 = 12 Hz), 7.57(s, 1H, C5—H), 7.61(d, 1H, C8—H, J1,2 = 8.8 Hz), 7.73 (s, 1H, Tr—H) p.p.m. 13C NMR (100 MHz, DMSO-d6): δ 31.0 (3C), 34.5, 49.2, 54.9, 113.7, 116.3, 116.4, 121.0, 123.7, 129.8, 147.0, 148.6, 150.4, 151.1, 159.5 p.p.m.. Analysis for C17H19N3O3. Calculated: C, 65.16; H, 6.11; N, 13.41%. Found: C, 65.12; H, 6.07; N, 13.39%.
Refinement
Crystal data, data collection and structure . The hydroxymethyl group at the 4-position of the triazole ring is disordered over two sets of sites, with a refined occupancy ratio of 0.418 (11):0.584 (11) for atoms C6A:C6B and O7A:O7B. The structure was refined as an = 0.2 (5).
details are summarized in Table 2Structural data
CCDC reference: 1509457
https://doi.org/10.1107/S2414314616016187/su4083sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314616016187/su4083Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2414314616016187/su4083Isup3.cml
C17H19N3O3 | Dx = 1.315 Mg m−3 |
Mr = 313.35 | Cu Kα radiation, λ = 1.54178 Å |
Orthorhombic, Pna21 | Cell parameters from 1581 reflections |
a = 8.9099 (12) Å | θ = 7.2–64.4° |
b = 24.550 (3) Å | µ = 0.75 mm−1 |
c = 7.2359 (11) Å | T = 293 K |
V = 1582.7 (4) Å3 | Block, colourless |
Z = 4 | 0.32 × 0.22 × 0.12 mm |
F(000) = 664 |
Bruker X8 Proteum diffractometer | 1565 reflections with I > 2σ(I) |
Radiation source: Bruker MicroStar microfocus rotating anode | Rint = 0.022 |
Helios multilayer optics monochromator | θmax = 64.4°, θmin = 7.2° |
Detector resolution: 18.4 pixels mm-1 | h = −10→9 |
φ and ω scans | k = −28→27 |
5136 measured reflections | l = −3→8 |
1581 independent reflections |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.030 | H-atom parameters constrained |
wR(F2) = 0.080 | w = 1/[σ2(Fo2) + (0.0492P)2 + 0.1878P] where P = (Fo2 + 2Fc2)/3 |
S = 1.07 | (Δ/σ)max < 0.001 |
1581 reflections | Δρmax = 0.10 e Å−3 |
227 parameters | Δρmin = −0.11 e Å−3 |
38 restraints | Absolute structure: Refined as an inversion twin |
Primary atom site location: structure-invariant direct methods | Absolute structure parameter: 0.2 (5) |
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. |
Refinement. Refined as a 2-component inversion twin. |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
C12 | 0.1311 (2) | 0.32195 (7) | 0.4515 (3) | 0.0390 (4) | |
N1 | 0.60931 (17) | 0.47866 (6) | 0.3641 (3) | 0.0440 (4) | |
C11 | 0.2465 (2) | 0.35946 (7) | 0.4284 (3) | 0.0362 (4) | |
H11 | 0.246706 | 0.381302 | 0.323334 | 0.043* | |
O16 | 0.47177 (19) | 0.33551 (6) | 0.8472 (3) | 0.0573 (4) | |
C13 | 0.1364 (2) | 0.28959 (8) | 0.6120 (3) | 0.0498 (5) | |
H13 | 0.060668 | 0.264168 | 0.631743 | 0.060* | |
C15 | 0.3613 (2) | 0.33239 (8) | 0.7134 (3) | 0.0431 (5) | |
O19 | 0.6737 (2) | 0.37446 (8) | 0.9624 (3) | 0.0858 (7) | |
C9 | 0.4845 (2) | 0.40488 (8) | 0.5398 (3) | 0.0399 (5) | |
N4 | 0.7328 (2) | 0.54936 (8) | 0.4439 (3) | 0.0576 (5) | |
C10 | 0.3626 (2) | 0.36557 (7) | 0.5575 (3) | 0.0359 (4) | |
C2 | 0.7321 (2) | 0.47844 (8) | 0.2567 (3) | 0.0438 (5) | |
H2 | 0.757906 | 0.453111 | 0.166558 | 0.053* | |
N5 | 0.6080 (2) | 0.52202 (8) | 0.4770 (3) | 0.0578 (6) | |
C17 | 0.5846 (3) | 0.37326 (9) | 0.8355 (4) | 0.0564 (6) | |
C8 | 0.4850 (2) | 0.44007 (9) | 0.3695 (4) | 0.0472 (5) | |
H8A | 0.490187 | 0.416841 | 0.261230 | 0.057* | |
H8B | 0.391225 | 0.460096 | 0.363693 | 0.057* | |
C18 | 0.5886 (2) | 0.40772 (9) | 0.6742 (4) | 0.0497 (5) | |
H18 | 0.666089 | 0.432863 | 0.662608 | 0.060* | |
C20 | 0.0017 (2) | 0.31619 (8) | 0.3138 (4) | 0.0442 (5) | |
C23 | 0.0228 (3) | 0.35213 (11) | 0.1440 (4) | 0.0645 (7) | |
H23A | 0.023399 | 0.389703 | 0.180780 | 0.097* | |
H23B | −0.058150 | 0.345981 | 0.058916 | 0.097* | |
H23C | 0.116334 | 0.343349 | 0.085332 | 0.097* | |
C21 | −0.1441 (2) | 0.33404 (11) | 0.4108 (5) | 0.0676 (7) | |
H21A | −0.135254 | 0.371364 | 0.448802 | 0.101* | |
H21B | −0.160897 | 0.311489 | 0.517178 | 0.101* | |
H21C | −0.226873 | 0.330379 | 0.326834 | 0.101* | |
C14 | 0.2491 (3) | 0.29416 (9) | 0.7405 (3) | 0.0531 (5) | |
H14 | 0.250115 | 0.271857 | 0.844358 | 0.064* | |
C6A | 0.957 (3) | 0.5456 (15) | 0.238 (6) | 0.0620 (7) | 0.418 (11) |
H6A1 | 0.981776 | 0.528038 | 0.121698 | 0.074* | 0.418 (11) |
H6A2 | 0.947595 | 0.584396 | 0.215757 | 0.074* | 0.418 (11) |
O7A | 1.0709 (6) | 0.5357 (3) | 0.3685 (13) | 0.076 (3) | 0.418 (11) |
H7A | 1.126711 | 0.562246 | 0.373797 | 0.113* | 0.418 (11) |
C6B | 0.958 (2) | 0.5453 (10) | 0.243 (4) | 0.0620 (7) | 0.582 (11) |
H6B1 | 0.949910 | 0.554755 | 0.113039 | 0.074* | 0.582 (11) |
H6B2 | 0.981856 | 0.578301 | 0.310511 | 0.074* | 0.582 (11) |
O7B | 1.0773 (4) | 0.5076 (3) | 0.2653 (10) | 0.0883 (19) | 0.582 (11) |
H7B | 1.086999 | 0.489670 | 0.170471 | 0.132* | 0.582 (11) |
C3 | 0.8105 (2) | 0.52358 (8) | 0.3088 (3) | 0.0456 (5) | |
C22 | −0.0126 (3) | 0.25684 (10) | 0.2520 (5) | 0.0696 (7) | |
H22A | −0.097310 | 0.253182 | 0.170927 | 0.104* | |
H22B | −0.026487 | 0.233981 | 0.358248 | 0.104* | |
H22C | 0.077008 | 0.246108 | 0.187940 | 0.104* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C12 | 0.0373 (9) | 0.0366 (8) | 0.0432 (11) | −0.0002 (7) | 0.0003 (10) | −0.0017 (9) |
N1 | 0.0402 (8) | 0.0519 (9) | 0.0397 (10) | −0.0097 (6) | −0.0021 (8) | −0.0082 (9) |
C11 | 0.0372 (10) | 0.0377 (8) | 0.0338 (11) | 0.0004 (7) | −0.0020 (8) | 0.0010 (8) |
O16 | 0.0706 (10) | 0.0580 (8) | 0.0434 (9) | 0.0082 (7) | −0.0239 (9) | 0.0048 (8) |
C13 | 0.0542 (12) | 0.0445 (10) | 0.0508 (13) | −0.0063 (9) | 0.0027 (11) | 0.0063 (10) |
C15 | 0.0509 (11) | 0.0427 (10) | 0.0356 (11) | 0.0083 (8) | −0.0067 (10) | −0.0006 (9) |
O19 | 0.0912 (14) | 0.0893 (12) | 0.0769 (14) | 0.0107 (10) | −0.0554 (13) | −0.0029 (12) |
C9 | 0.0339 (9) | 0.0470 (10) | 0.0388 (11) | 0.0024 (7) | −0.0050 (9) | −0.0057 (9) |
N4 | 0.0570 (10) | 0.0593 (10) | 0.0566 (12) | −0.0176 (8) | 0.0027 (11) | −0.0126 (10) |
C10 | 0.0372 (9) | 0.0382 (8) | 0.0323 (10) | 0.0039 (7) | −0.0032 (9) | −0.0021 (8) |
C2 | 0.0435 (11) | 0.0489 (10) | 0.0389 (11) | −0.0026 (8) | 0.0026 (9) | −0.0026 (9) |
N5 | 0.0543 (10) | 0.0618 (11) | 0.0573 (14) | −0.0144 (9) | 0.0083 (10) | −0.0190 (11) |
C17 | 0.0573 (13) | 0.0580 (12) | 0.0538 (15) | 0.0130 (10) | −0.0274 (13) | −0.0112 (12) |
C8 | 0.0399 (10) | 0.0591 (11) | 0.0426 (12) | −0.0140 (8) | −0.0071 (10) | 0.0021 (11) |
C18 | 0.0420 (10) | 0.0566 (11) | 0.0505 (13) | 0.0010 (9) | −0.0124 (11) | −0.0103 (11) |
C20 | 0.0354 (9) | 0.0446 (10) | 0.0525 (13) | −0.0069 (7) | −0.0045 (10) | 0.0017 (10) |
C23 | 0.0521 (12) | 0.0841 (16) | 0.0572 (16) | −0.0168 (12) | −0.0195 (13) | 0.0131 (14) |
C21 | 0.0410 (11) | 0.0788 (15) | 0.083 (2) | −0.0002 (10) | 0.0005 (14) | −0.0012 (15) |
C14 | 0.0702 (13) | 0.0482 (11) | 0.0409 (12) | 0.0017 (10) | −0.0016 (11) | 0.0120 (10) |
C6A | 0.0507 (13) | 0.0732 (15) | 0.062 (2) | −0.0176 (11) | 0.0022 (14) | 0.0079 (14) |
O7A | 0.049 (3) | 0.085 (4) | 0.092 (6) | −0.014 (3) | −0.016 (3) | 0.022 (4) |
C6B | 0.0507 (13) | 0.0732 (15) | 0.062 (2) | −0.0176 (11) | 0.0022 (14) | 0.0079 (14) |
O7B | 0.0576 (19) | 0.094 (3) | 0.113 (4) | −0.0042 (19) | 0.029 (2) | −0.010 (3) |
C3 | 0.0431 (10) | 0.0502 (10) | 0.0434 (12) | −0.0084 (8) | −0.0005 (10) | 0.0036 (10) |
C22 | 0.0727 (15) | 0.0572 (13) | 0.0789 (19) | −0.0102 (11) | −0.0213 (16) | −0.0117 (13) |
C12—C11 | 1.391 (3) | C18—H18 | 0.9300 |
C12—C13 | 1.408 (3) | C20—C23 | 1.524 (4) |
C12—C20 | 1.531 (3) | C20—C22 | 1.529 (3) |
N1—C2 | 1.342 (3) | C20—C21 | 1.540 (3) |
N1—N5 | 1.342 (2) | C23—H23A | 0.9600 |
N1—C8 | 1.458 (2) | C23—H23B | 0.9600 |
C11—C10 | 1.402 (3) | C23—H23C | 0.9600 |
C11—H11 | 0.9300 | C21—H21A | 0.9600 |
O16—C17 | 1.370 (3) | C21—H21B | 0.9600 |
O16—C15 | 1.383 (3) | C21—H21C | 0.9600 |
C13—C14 | 1.373 (3) | C14—H14 | 0.9300 |
C13—H13 | 0.9300 | C6A—O7A | 1.411 (18) |
C15—C14 | 1.385 (3) | C6A—C3 | 1.50 (4) |
C15—C10 | 1.391 (3) | C6A—H6A1 | 0.9700 |
O19—C17 | 1.214 (3) | C6A—H6A2 | 0.9700 |
C9—C18 | 1.346 (3) | O7A—H7A | 0.8200 |
C9—C10 | 1.458 (3) | C6B—O7B | 1.416 (15) |
C9—C8 | 1.505 (3) | C6B—C3 | 1.50 (3) |
N4—N5 | 1.320 (3) | C6B—H6B1 | 0.9700 |
N4—C3 | 1.355 (3) | C6B—H6B2 | 0.9700 |
C2—C3 | 1.363 (3) | O7B—H7B | 0.8200 |
C2—H2 | 0.9300 | C22—H22A | 0.9600 |
C17—C18 | 1.442 (4) | C22—H22B | 0.9600 |
C8—H8A | 0.9700 | C22—H22C | 0.9600 |
C8—H8B | 0.9700 | ||
C11—C12—C13 | 116.66 (19) | C22—C20—C21 | 109.52 (19) |
C11—C12—C20 | 122.66 (18) | C12—C20—C21 | 108.2 (2) |
C13—C12—C20 | 120.67 (17) | C20—C23—H23A | 109.5 |
C2—N1—N5 | 111.27 (16) | C20—C23—H23B | 109.5 |
C2—N1—C8 | 129.22 (18) | H23A—C23—H23B | 109.5 |
N5—N1—C8 | 119.51 (17) | C20—C23—H23C | 109.5 |
C12—C11—C10 | 122.41 (19) | H23A—C23—H23C | 109.5 |
C12—C11—H11 | 118.8 | H23B—C23—H23C | 109.5 |
C10—C11—H11 | 118.8 | C20—C21—H21A | 109.5 |
C17—O16—C15 | 121.1 (2) | C20—C21—H21B | 109.5 |
C14—C13—C12 | 122.45 (19) | H21A—C21—H21B | 109.5 |
C14—C13—H13 | 118.8 | C20—C21—H21C | 109.5 |
C12—C13—H13 | 118.8 | H21A—C21—H21C | 109.5 |
O16—C15—C14 | 116.9 (2) | H21B—C21—H21C | 109.5 |
O16—C15—C10 | 121.97 (18) | C13—C14—C15 | 119.2 (2) |
C14—C15—C10 | 121.14 (19) | C13—C14—H14 | 120.4 |
C18—C9—C10 | 118.9 (2) | C15—C14—H14 | 120.4 |
C18—C9—C8 | 124.07 (18) | O7A—C6A—C3 | 110 (3) |
C10—C9—C8 | 116.99 (17) | O7A—C6A—H6A1 | 109.8 |
N5—N4—C3 | 108.91 (18) | C3—C6A—H6A1 | 109.8 |
C15—C10—C11 | 118.14 (17) | O7A—C6A—H6A2 | 109.8 |
C15—C10—C9 | 117.70 (18) | C3—C6A—H6A2 | 109.8 |
C11—C10—C9 | 124.15 (18) | H6A1—C6A—H6A2 | 108.2 |
N1—C2—C3 | 104.73 (19) | C6A—O7A—H7A | 109.5 |
N1—C2—H2 | 127.6 | O7B—C6B—C3 | 112.9 (18) |
C3—C2—H2 | 127.6 | O7B—C6B—H6B1 | 109.0 |
N4—N5—N1 | 106.58 (18) | C3—C6B—H6B1 | 109.0 |
O19—C17—O16 | 116.7 (3) | O7B—C6B—H6B2 | 109.0 |
O19—C17—C18 | 125.6 (2) | C3—C6B—H6B2 | 109.0 |
O16—C17—C18 | 117.72 (19) | H6B1—C6B—H6B2 | 107.8 |
N1—C8—C9 | 113.38 (18) | C6B—O7B—H7B | 109.5 |
N1—C8—H8A | 108.9 | N4—C3—C2 | 108.50 (18) |
C9—C8—H8A | 108.9 | N4—C3—C6B | 120.9 (11) |
N1—C8—H8B | 108.9 | C2—C3—C6B | 130.6 (11) |
C9—C8—H8B | 108.9 | N4—C3—C6A | 121.5 (15) |
H8A—C8—H8B | 107.7 | C2—C3—C6A | 130.0 (15) |
C9—C18—C17 | 122.5 (2) | C20—C22—H22A | 109.5 |
C9—C18—H18 | 118.7 | C20—C22—H22B | 109.5 |
C17—C18—H18 | 118.7 | H22A—C22—H22B | 109.5 |
C23—C20—C22 | 109.0 (2) | C20—C22—H22C | 109.5 |
C23—C20—C12 | 112.25 (16) | H22A—C22—H22C | 109.5 |
C22—C20—C12 | 109.95 (17) | H22B—C22—H22C | 109.5 |
C23—C20—C21 | 107.9 (2) |
Cg3 is the centroid of the C10–C15 ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
O7B—H7B···N4i | 0.82 | 2.49 | 3.198 (7) | 146 |
C2—H2···O19ii | 0.93 | 2.54 | 3.365 (3) | 147 |
C23—H23B···O19iii | 0.96 | 2.59 | 3.421 (3) | 146 |
C22—H22B···Cg3iv | 0.96 | 2.99 | 3.818 (3) | 145 |
Symmetry codes: (i) −x+2, −y+1, z−1/2; (ii) x, y, z−1; (iii) x−1, y, z−1; (iv) x−1/2, −y+1/2, z. |
Acknowledgements
MM thanks the UGC, New Delhi, Government of India, for awarding a project under the title F. No. 41–920/2012(SR) dated: 25–07-2012. SD is grateful to the Council of Scientific and Industrial Research, New Delhi, India, for financial assistance [grant No. 02 (0172)/13/EMR-II].
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