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Journal logoIUCrDATA
ISSN: 2414-3146

4-[(4-Hy­dr­oxy­methyl-2H-1,2,3-triazol-2-yl)meth­yl]-6-iso­propyl-2H-chromen-2-one

CROSSMARK_Color_square_no_text.svg

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

Edited by E. R. T. Tiekink, Sunway University, Malaysia (Received 28 November 2016; accepted 14 December 2016; online 20 December 2016)

In the title compound, C16H17N3O3, the chromene ring is planar, with a maximum deviation of 0.017 (4) Å for the ring O atom. The triazole and the chromene rings, bridged by a methyl­ene C atom, are inclined to one another by 78.3 (2)°. In the crystal, methyl­ene–triazole C—H⋯N hydrogen bonds lead to the formation of helical supra­molecular chains along the b axis. The sample was refined as an inversion twin. The terminal methyl­hydroxy group is disordered over two sets of sites [site occupancy = 0.610 (13) for the major component].

3D view (loading...)
[Scheme 3D1]
Chemical scheme
[Scheme 1]

Structure description

Coumarins and their derivatives form represent an important class of natural and synthetic heterocycles that are often linked to a broad array of biological activities (Gaspar et al., 2015[Gaspar, A., Milhazes, N., Santana, L., Uriarte, E., Borges, F. & Matos, M. J. (2015). Curr. Top. Med. Chem. 15, 432-445.]), such as anti-bacterial (Basanagouda et al., 2009[Basanagouda, M., Kulkarni, M. V., Sharma, D., Gupta, V. K., Pranesha, Sandhyarani, P. & Rasal, V. P. (2009). J. Chem. Sci. 121, 485-495.]), anti-oxidant (Vukovic et al., 2010[Vukovic, N., Sukdolak, S., Solujic, S. & Niciforovic, N. (2010). Arch. Pharm. Res. 33, 5-15.]) and anti-inflammatory (Emmanuel-Giota et al., 2001[Emmanuel-Giota, A. A., Fylaktakidou, K. C., Litinas, K. E., Nicolaides, D. N. & Hadjipavlou-Litina, D. J. (2001). J. Heterocycl. Chem. 38, 717-722.]). These derivatives are also used in the pharmaceutical industry as precursor reagents in the synthesis of a number of synthetic anti-coagulant pharmaceuticals (Bairagi et al., 2012[Bairagi, S. H., Salaskar, P. P., Loke, S. D., Surve, N. N., Tandel, D. V. & Dusara, M. D. (2012). Int. J. Pharm. Res. 4, 16-19.]). As part of our ongoing studies of coumarin–triazole derivatives (El-Khatatneh et al., 2016[El-Khatatneh, N., Chandra, Shamala, D., Shivashankar, K. & Mahendra, M. (2016). IUCrData, 1, x161618.]), the title compound was synthesized and its crystal structure is reported herein.

In the mol­ecular structure (Fig. 1[link]), the chromene unit (O19/C9/C10/C18/C20/C22) is planar, with a maximum deviation of 0.017 (4) Å for the ring atom O21. The triazole (N4/N5/N6/C3/C7) and the chromene (O19/C9/C10/C18/C20/C22) rings, bridged via a methyl­ene-C8 atom, are inclined to one another by 78.3 (2)°. The intra-ring bond conformation between the chromene and triazole moieties are also characterized by torsion angles of 100.2 (5)° [for N4—N5—C8—C9] and −178.6 (3)° [for C10—C9—C8—N5]. The hy­droxy­methyl group is not coplanar with the triazole ring, as indicated by torsion angle C7—C3—C2A—O1A = 77 (2)°. One methyl unit of the isopropyl group is not co-planar with the chromene ring, as suggested by the C11—C12—C13—C14 torsion angle of 40.5 (8)°, while the other methyl group is below, with a C11—C12—C13—C15 torsion angle of −88.1 (6)°.

[Figure 1]
Figure 1
Perspective diagram of the title mol­ecule, showing 50% probability displacement ellipsoids and both components of the disordered hy­droxy­methyl group.

The crystal features C8—H8A⋯N6 hydrogen bonds (Table 1[link]), which lead to helical supra­molecular chains along the b axis. The mol­ecular packing exhibits layered stacking when viewed along the b axis, as shown in Fig. 2[link].

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C8—H8A⋯N6i 0.97 2.55 3.070 (6) 114
Symmetry code: (i) [-x, y-{\script{1\over 2}}, -z].
[Figure 2]
Figure 2
Packing diagram of the mol­ecule viewed parallel to the b axis.

Synthesis and crystallization

The general procedure for the synthesis of N2 coumarin 1,2,3-triazoles has been reported (Shamala et al., 2016[Shamala, D., Shivashankar, K., Chandra & Mahendra, M. (2016). Synth. Commun. 46, 433-441.]). To a solution of propargyl alcohol (0.11 g, 1.9 mmol) in acetone, CuI (10 mol%) and tri­ethyl­amine (0.19 g, 1.9 mmol) were added. The mixture was stirred at room temperature for 15 min. Then, 4-(azido­meth­yl)-6-isopropyl-2H-chromen-2-one (1.9 mmol) was added and the resulting mixture was stirred until the starting material was consumed as judged 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 to give colourless blocks of the title compound.

Yield 85%; colourless solid; m.p. 466–468 K. IR (KBr, cm−1): 1720 (lactone C=O), 3190 (OH). 1H NMR (400 MHz, CDCl3): δ 1.25 (d, 6H, 2-CH3 of i-Pr), J = 5.2 Hz), 2.06 (s, 1H, OH), 2.95 (m, 1H, CH of i-Pr, J = 5.2 Hz), 4.93 (s, 2H, –CH2O–), 5.97 (s, 2H, –CH2N–), 6.21 (s, 1H, C3—H), 7.36 (d, 1H, C7—H, J = 8.4 Hz), 7.55 (d, 1H, C8—H, J1,2 = 7.6 Hz), 7.70 (s, 1H, C5—H), 8.38 (s, 1H, Tr-H) p.p.m. 13C NMR (100 MHz, DMSO-d6): δ 16.9 (2C), 26.7, 43.3, 49.5, 101.1, 107.9, 109.6, 110.4, 113.7, 124.2, 138.7, 141.0, 142.9, 145.0, 153.0 p.p.m. Analysis calculated for C16H17N3O3: C, 64.20; H, 5.72; N, 14.04%; found: C, 64.08; H, 5.60; N, 14.00%.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2[link]. The sample was refined as an inversion twin. The terminal methyl­hydroxyl group is disordered over two sets of sites (site occupancy = 0.610 (13) for the major component).

Table 2
Experimental details

Crystal data
Chemical formula C16H17N3O3
Mr 299.32
Crystal system, space group Monoclinic, P21
Temperature (K) 273
a, b, c (Å) 8.715 (5), 7.301 (4), 12.113 (6)
β (°) 101.209 (9)
V3) 756.0 (7)
Z 2
Radiation type Mo Kα
μ (mm−1) 0.09
Crystal size (mm) 0.35 × 0.25 × 0.15
 
Data collection
Diffractometer Bruker MicroStar microfocus rotating anode
No. of measured, independent and observed [I > 2σ(I)] reflections 7069, 2680, 2307
Rint 0.026
(sin θ/λ)max−1) 0.594
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.058, 0.173, 1.06
No. of reflections 2680
No. of parameters 214
No. of restraints 38
H-atom treatment H-atom parameters constrained
Δρmax, Δρmin (e Å−3) 0.25, −0.28
Absolute structure Flack x determined using 884 quotients [(I+)−(I)]/[(I+)+(I)] (Parsons et al., 2013[Parsons, S., Flack, H. D. & Wagner, T. (2013). Acta Cryst. B69, 249-259.])
Absolute structure parameter 0.4 (6)
Computer programs: APEX2 and SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]), SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]), Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]), SHELXL2016 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Structural data


Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2016 (Sheldrick, 2015); molecular graphics: PLATON (Spek, 2009) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL2016 (Sheldrick, 2015) and PLATON (Spek, 2009).

4-[(4-Hydroxymethyl-2H-1,2,3-triazol-2-yl)methyl]-6-isopropyl-2H-chromen-2-one top
Crystal data top
C16H17N3O3F(000) = 316
Mr = 299.32Dx = 1.315 Mg m3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
a = 8.715 (5) ÅCell parameters from 2680 reflections
b = 7.301 (4) Åθ = 1.7–25.0°
c = 12.113 (6) ŵ = 0.09 mm1
β = 101.209 (9)°T = 273 K
V = 756.0 (7) Å3Block, colourless
Z = 20.35 × 0.25 × 0.15 mm
Data collection top
Bruker MicroStar microfocus rotating anode
diffractometer
Rint = 0.026
Detector resolution: 18.4 pixels mm-1θmax = 25.0°, θmin = 1.7°
φ and ω scansh = 1010
7069 measured reflectionsk = 88
2680 independent reflectionsl = 1414
2307 reflections with I > 2σ(I)
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.058H-atom parameters constrained
wR(F2) = 0.173 w = 1/[σ2(Fo2) + (0.1139P)2 + 0.0997P]
where P = (Fo2 + 2Fc2)/3
S = 1.06(Δ/σ)max < 0.001
2680 reflectionsΔρmax = 0.25 e Å3
214 parametersΔρmin = 0.28 e Å3
38 restraintsAbsolute structure: Flack x determined using 884 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013)
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.4 (6)
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
C2A0.432 (4)0.285 (8)0.109 (3)0.080 (3)0.610 (13)
H2A10.4747730.3983440.0750050.096*0.610 (13)
H2A20.3992220.3043240.1897410.096*0.610 (13)
O1A0.5459 (9)0.1448 (13)0.0887 (7)0.109 (4)0.610 (13)
H1A0.5676220.1232960.0210520.164*0.610 (13)
C2B0.445 (6)0.277 (14)0.090 (6)0.080 (3)0.390 (13)
H2B10.4301610.3964960.1260130.096*0.390 (13)
H2B20.4674010.1911080.1457520.096*0.390 (13)
O1B0.5778 (11)0.2871 (17)0.0017 (10)0.089 (4)0.390 (13)
H1B0.5607480.3593430.0462670.133*0.390 (13)
O190.0897 (4)0.2890 (4)0.3404 (2)0.0600 (8)
C110.1689 (4)0.1100 (6)0.2962 (4)0.0508 (10)
H110.1916400.2105420.2486650.061*
C90.0411 (4)0.0058 (5)0.1920 (3)0.0446 (9)
C100.0518 (5)0.0111 (5)0.2791 (3)0.0453 (9)
C180.0219 (5)0.1603 (6)0.3514 (4)0.0509 (10)
C200.1754 (5)0.2769 (6)0.2573 (4)0.0550 (11)
C220.1485 (5)0.1217 (6)0.1844 (3)0.0488 (10)
H220.2084920.1087180.1291990.059*
C170.1015 (6)0.1867 (7)0.4379 (4)0.0612 (12)
H170.0780510.2860370.4863580.073*
N50.1126 (4)0.1759 (5)0.0339 (3)0.0497 (8)
C120.2519 (5)0.0858 (7)0.3810 (4)0.0562 (11)
C80.0117 (5)0.1697 (6)0.1159 (4)0.0576 (11)
H8A0.0274640.2799600.1613560.069*
H8B0.0964450.1680510.0766270.069*
O210.2705 (4)0.3975 (6)0.2539 (3)0.0804 (11)
C70.1952 (5)0.0965 (6)0.1125 (3)0.0530 (10)
H70.2040760.0388260.1794620.064*
N40.2440 (5)0.2750 (7)0.0358 (4)0.0734 (12)
C160.2155 (6)0.0646 (7)0.4515 (4)0.0642 (12)
H160.2699290.0826880.5094500.077*
N60.0842 (5)0.0676 (5)0.0562 (3)0.0628 (10)
C30.2948 (6)0.2225 (7)0.0586 (4)0.0636 (12)
C130.3833 (5)0.2128 (8)0.3976 (5)0.0683 (13)
H130.3924940.2005900.4766510.082*
C140.3496 (9)0.4077 (10)0.3806 (8)0.121 (3)
H14A0.4297740.4822330.4019630.182*
H14B0.2501090.4392620.4259260.182*
H14C0.3470010.4285040.3026840.182*
C150.5364 (6)0.1510 (13)0.3291 (7)0.120 (3)
H15A0.5429930.1874890.2522000.180*
H15B0.5436680.0200200.3331030.180*
H15C0.6205280.2057150.3581260.180*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C2A0.086 (6)0.071 (6)0.097 (12)0.005 (5)0.050 (5)0.015 (11)
O1A0.109 (6)0.109 (7)0.125 (7)0.029 (5)0.063 (5)0.052 (5)
C2B0.086 (6)0.071 (6)0.097 (12)0.005 (5)0.050 (5)0.015 (11)
O1B0.069 (6)0.093 (8)0.110 (8)0.029 (6)0.033 (6)0.033 (6)
O190.0690 (18)0.0526 (18)0.0603 (17)0.0160 (15)0.0173 (15)0.0159 (14)
C110.048 (2)0.045 (2)0.060 (2)0.0010 (19)0.0126 (18)0.0015 (19)
C90.047 (2)0.0389 (19)0.047 (2)0.0028 (17)0.0077 (16)0.0007 (16)
C100.048 (2)0.041 (2)0.048 (2)0.0023 (16)0.0110 (16)0.0018 (17)
C180.052 (2)0.051 (2)0.051 (2)0.0022 (19)0.0131 (17)0.0017 (19)
C200.053 (2)0.055 (3)0.058 (2)0.014 (2)0.0144 (19)0.003 (2)
C220.052 (2)0.048 (2)0.049 (2)0.0036 (19)0.0154 (17)0.0005 (18)
C170.071 (3)0.060 (3)0.055 (2)0.002 (2)0.019 (2)0.006 (2)
N50.0589 (19)0.0377 (17)0.0539 (19)0.0035 (16)0.0139 (15)0.0042 (15)
C120.049 (2)0.059 (3)0.063 (2)0.007 (2)0.0184 (18)0.015 (2)
C80.066 (2)0.046 (2)0.067 (3)0.011 (2)0.028 (2)0.009 (2)
O210.083 (2)0.073 (2)0.092 (2)0.039 (2)0.0307 (19)0.023 (2)
C70.080 (3)0.039 (2)0.045 (2)0.001 (2)0.0247 (19)0.0076 (18)
N40.080 (3)0.059 (3)0.084 (3)0.003 (2)0.023 (2)0.008 (2)
C160.065 (3)0.068 (3)0.065 (3)0.011 (2)0.027 (2)0.006 (2)
N60.077 (2)0.048 (2)0.066 (2)0.0081 (19)0.0191 (18)0.0050 (18)
C30.070 (3)0.055 (3)0.072 (3)0.006 (2)0.030 (2)0.009 (2)
C130.058 (3)0.071 (3)0.080 (3)0.002 (2)0.024 (2)0.015 (3)
C140.119 (6)0.065 (4)0.199 (8)0.025 (4)0.079 (6)0.000 (5)
C150.063 (3)0.134 (7)0.153 (7)0.020 (4)0.002 (4)0.047 (6)
Geometric parameters (Å, º) top
C2Aa—O1A1.41 (4)C17—C161.368 (7)
C2Aa—C31.52 (5)C17—H170.9300
C2Aa—H2A10.9700N5—N61.331 (5)
C2Aa—H2A20.9700N5—N41.351 (5)
O1Aa—H1A0.8200N5—C81.450 (5)
C2Bb—O1B1.42 (4)C12—C161.389 (7)
C2Bb—C31.49 (8)C12—C131.517 (6)
C2Bb—H2B10.9700C8—H8A0.9700
C2Bb—H2B20.9700C8—H8B0.9700
O1Bb—H1B0.8200C7—N61.305 (6)
O19—C201.368 (5)C7—C31.343 (7)
O19—C181.377 (5)C7—H70.9300
C11—C121.378 (6)N4—C31.359 (7)
C11—C101.396 (5)C16—H160.9300
C11—H110.9300C13—C141.476 (10)
C9—C221.335 (6)C13—C151.497 (8)
C9—C101.454 (5)C13—H130.9800
C9—C81.502 (6)C14—H14A0.9600
C10—C181.390 (6)C14—H14B0.9600
C18—C171.378 (6)C14—H14C0.9600
C20—O211.215 (5)C15—H15A0.9600
C20—C221.428 (6)C15—H15B0.9600
C22—H220.9300C15—H15C0.9600
O1Aa—C2Aa—C3107 (4)C11—C12—C13122.7 (5)
O1Aa—C2Aa—H2A1110.3C16—C12—C13119.3 (4)
C3—C2Aa—H2A1110.3N5—C8—C9113.1 (3)
O1Aa—C2Aa—H2A2110.3N5—C8—H8A109.0
C3—C2Aa—H2A2110.3C9—C8—H8A109.0
H2A1a—C2Aa—H2A2108.5N5—C8—H8B109.0
C2Aa—O1Aa—H1A109.5C9—C8—H8B109.0
O1Bb—C2Bb—C3117 (5)H8A—C8—H8B107.8
O1Bb—C2Bb—H2B1108.1N6—C7—C3109.3 (4)
C3—C2Bb—H2B1108.1N6—C7—H7125.3
O1Bb—C2Bb—H2B2108.1C3—C7—H7125.3
C3—C2Bb—H2B2108.1N5—N4—C3104.4 (4)
H2B1b—C2Bb—H2B2107.3C17—C16—C12121.7 (4)
C2Bb—O1Bb—H1B109.5C17—C16—H16119.1
C20—O19—C18121.6 (3)C12—C16—H16119.1
C12—C11—C10122.3 (4)C7—N6—N5107.1 (4)
C12—C11—H11118.9C7—C3—N4108.5 (4)
C10—C11—H11118.9C7—C3—C2B125 (3)
C22—C9—C10119.2 (4)N4—C3—C2B126 (3)
C22—C9—C8123.5 (4)C7—C3—C2A120 (2)
C10—C9—C8117.4 (3)N4—C3—C2A132 (2)
C18—C10—C11117.1 (4)C14—C13—C15113.2 (7)
C18—C10—C9117.5 (4)C14—C13—C12113.3 (5)
C11—C10—C9125.5 (4)C15—C13—C12110.9 (5)
O19—C18—C17116.6 (4)C14—C13—H13106.3
O19—C18—C10121.5 (4)C15—C13—H13106.3
C17—C18—C10121.9 (4)C12—C13—H13106.3
O21—C20—O19116.8 (4)C13—C14—H14A109.5
O21—C20—C22125.8 (4)C13—C14—H14B109.5
O19—C20—C22117.3 (3)H14A—C14—H14B109.5
C9—C22—C20122.9 (4)C13—C14—H14C109.5
C9—C22—H22118.5H14A—C14—H14C109.5
C20—C22—H22118.5H14B—C14—H14C109.5
C16—C17—C18119.0 (5)C13—C15—H15A109.5
C16—C17—H17120.5C13—C15—H15B109.5
C18—C17—H17120.5H15A—C15—H15B109.5
N6—N5—N4110.7 (4)C13—C15—H15C109.5
N6—N5—C8120.1 (3)H15A—C15—H15C109.5
N4—N5—C8129.1 (4)H15B—C15—H15C109.5
C11—C12—C16118.0 (4)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8A···N6i0.972.553.070 (6)114
Symmetry code: (i) x, y1/2, z.
 

Acknowledgements

MM thanks the UGC, New Delhi, India, for awarding a project under the title F. No. 41-920/2012(SR) from 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].

References

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