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

El-Khatatneh, N.; Chandra; Shamala, D.; Shivashankar, K.; Mahendra, M.

doi:10.1107/S2414314616019891

organic compounds

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ISSN: 2414-3146

Volume 1| Part 12| December 2016| x161989

https://doi.org/10.1107/S2414314616019891

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

Nasseem El-Khatatneh,^a Chandra,^a D. Shamala,^b K. Shivashankar ^b and M. Mahendra ^a ^*

^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].

Keywords: crystal structure; chromones; triazole; conformation.

CCDC reference: 1523344

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 ), such as anti-bacterial (Basanagouda et al., 2009 ), anti-oxidant (Vukovic et al., 2010 ) and anti-inflammatory (Emmanuel-Giota et al., 2001 ). 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 ). As part of our ongoing studies of coumarin–triazole derivatives (El-Khatatneh et al., 2016 ), the title compound was synthesized and its crystal structure is reported herein.

In the molecular structure (Fig. 1), 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
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), 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.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	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
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 ). 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, J_1,2 = 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. 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
M_r	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)
V (Å³)	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
R_int	0.026
(sin θ/λ)_max (Å⁻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
Δρ_max, Δρ_min (e Å⁻³)	0.25, −0.28
Absolute structure	Flack x determined using 884 quotients [(I⁺)−(I⁻)]/[(I⁺)+(I⁻)] (Parsons et al., 2013 )
Absolute structure parameter	0.4 (6)
Computer programs: APEX2 and SAINT (Bruker, 2009 ), SHELXS97 (Sheldrick, 2008 ), Mercury (Macrae et al., 2008 ), SHELXL2016 (Sheldrick, 2015 ) and PLATON (Spek, 2009 ).

Structural data

CCDC reference: 1523344

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S2414314616019891/tk4026sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314616019891/tk4026Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314616019891/tk4026Isup3.cml

checkCIF report

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

C₁₆H₁₇N₃O₃	F(000) = 316
M_r = 299.32	D_x = 1.315 Mg m⁻³
Monoclinic, P2₁	Mo Kα radiation, λ = 0.71073 Å
a = 8.715 (5) Å	Cell parameters from 2680 reflections
b = 7.301 (4) Å	θ = 1.7–25.0°
c = 12.113 (6) Å	µ = 0.09 mm⁻¹
β = 101.209 (9)°	T = 273 K
V = 756.0 (7) Å³	Block, colourless
Z = 2	0.35 × 0.25 × 0.15 mm

Data collection top

Bruker MicroStar microfocus rotating anode diffractometer	R_int = 0.026
Detector resolution: 18.4 pixels mm^-1	θ_max = 25.0°, θ_min = 1.7°
φ and ω scans	h = −10→10
7069 measured reflections	k = −8→8
2680 independent reflections	l = −14→14
2307 reflections with I > 2σ(I)

Refinement top

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)] = 0.058	H-atom parameters constrained
wR(F²) = 0.173	w = 1/[σ²(F_o²) + (0.1139P)² + 0.0997P] where P = (F_o² + 2F_c²)/3
S = 1.06	(Δ/σ)_max < 0.001
2680 reflections	Δρ_max = 0.25 e Å⁻³
214 parameters	Δρ_min = −0.28 e Å⁻³
38 restraints	Absolute structure: Flack x determined using 884 quotients [(I⁺)-(I^-)]/[(I⁺)+(I^-)] (Parsons et al., 2013)
Primary atom site location: structure-invariant direct methods	Absolute 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

	x	y	z	U_iso*/U_eq	Occ. (<1)
C2A	0.432 (4)	−0.285 (8)	−0.109 (3)	0.080 (3)	0.610 (13)
H2A1	0.474773	−0.398344	−0.075005	0.096*	0.610 (13)
H2A2	0.399222	−0.304324	−0.189741	0.096*	0.610 (13)
O1A	0.5459 (9)	−0.1448 (13)	−0.0887 (7)	0.109 (4)	0.610 (13)
H1A	0.567622	−0.123296	−0.021052	0.164*	0.610 (13)
C2B	0.445 (6)	−0.277 (14)	−0.090 (6)	0.080 (3)	0.390 (13)
H2B1	0.430161	−0.396496	−0.126013	0.096*	0.390 (13)
H2B2	0.467401	−0.191108	−0.145752	0.096*	0.390 (13)
O1B	0.5778 (11)	−0.2871 (17)	−0.0017 (10)	0.089 (4)	0.390 (13)
H1B	0.560748	−0.359343	0.046267	0.133*	0.390 (13)
O19	0.0897 (4)	0.2890 (4)	0.3404 (2)	0.0600 (8)
C11	−0.1689 (4)	−0.1100 (6)	0.2962 (4)	0.0508 (10)
H11	−0.191640	−0.210542	0.248665	0.061*
C9	0.0411 (4)	−0.0058 (5)	0.1920 (3)	0.0446 (9)
C10	−0.0518 (5)	0.0111 (5)	0.2791 (3)	0.0453 (9)
C18	−0.0219 (5)	0.1603 (6)	0.3514 (4)	0.0509 (10)
C20	0.1754 (5)	0.2769 (6)	0.2573 (4)	0.0550 (11)
C22	0.1485 (5)	0.1217 (6)	0.1844 (3)	0.0488 (10)
H22	0.208492	0.108718	0.129199	0.059*
C17	−0.1015 (6)	0.1867 (7)	0.4379 (4)	0.0612 (12)
H17	−0.078051	0.286037	0.486358	0.073*
N5	0.1126 (4)	−0.1759 (5)	0.0339 (3)	0.0497 (8)
C12	−0.2519 (5)	−0.0858 (7)	0.3810 (4)	0.0562 (11)
C8	0.0117 (5)	−0.1697 (6)	0.1159 (4)	0.0576 (11)
H8A	0.027464	−0.279960	0.161356	0.069*
H8B	−0.096445	−0.168051	0.076627	0.069*
O21	0.2705 (4)	0.3975 (6)	0.2539 (3)	0.0804 (11)
C7	0.1952 (5)	−0.0965 (6)	−0.1125 (3)	0.0530 (10)
H7	0.204076	−0.038826	−0.179462	0.064*
N4	0.2440 (5)	−0.2750 (7)	0.0358 (4)	0.0734 (12)
C16	−0.2155 (6)	0.0646 (7)	0.4515 (4)	0.0642 (12)
H16	−0.269929	0.082688	0.509450	0.077*
N6	0.0842 (5)	−0.0676 (5)	−0.0562 (3)	0.0628 (10)
C3	0.2948 (6)	−0.2225 (7)	−0.0586 (4)	0.0636 (12)
C13	−0.3833 (5)	−0.2128 (8)	0.3976 (5)	0.0683 (13)
H13	−0.392494	−0.200590	0.476651	0.082*
C14	−0.3496 (9)	−0.4077 (10)	0.3806 (8)	0.121 (3)
H14A	−0.429774	−0.482233	0.401963	0.182*
H14B	−0.250109	−0.439262	0.425926	0.182*
H14C	−0.347001	−0.428504	0.302684	0.182*
C15	−0.5364 (6)	−0.1510 (13)	0.3291 (7)	0.120 (3)
H15A	−0.542993	−0.187489	0.252200	0.180*
H15B	−0.543668	−0.020020	0.333103	0.180*
H15C	−0.620528	−0.205715	0.358126	0.180*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C2A	0.086 (6)	0.071 (6)	0.097 (12)	−0.005 (5)	0.050 (5)	−0.015 (11)
O1A	0.109 (6)	0.109 (7)	0.125 (7)	−0.029 (5)	0.063 (5)	−0.052 (5)
C2B	0.086 (6)	0.071 (6)	0.097 (12)	−0.005 (5)	0.050 (5)	−0.015 (11)
O1B	0.069 (6)	0.093 (8)	0.110 (8)	0.029 (6)	0.033 (6)	0.033 (6)
O19	0.0690 (18)	0.0526 (18)	0.0603 (17)	−0.0160 (15)	0.0173 (15)	−0.0159 (14)
C11	0.048 (2)	0.045 (2)	0.060 (2)	−0.0010 (19)	0.0126 (18)	0.0015 (19)
C9	0.047 (2)	0.0389 (19)	0.047 (2)	0.0028 (17)	0.0077 (16)	0.0007 (16)
C10	0.048 (2)	0.041 (2)	0.048 (2)	0.0023 (16)	0.0110 (16)	0.0018 (17)
C18	0.052 (2)	0.051 (2)	0.051 (2)	−0.0022 (19)	0.0131 (17)	0.0017 (19)
C20	0.053 (2)	0.055 (3)	0.058 (2)	−0.014 (2)	0.0144 (19)	−0.003 (2)
C22	0.052 (2)	0.048 (2)	0.049 (2)	−0.0036 (19)	0.0154 (17)	0.0005 (18)
C17	0.071 (3)	0.060 (3)	0.055 (2)	0.002 (2)	0.019 (2)	−0.006 (2)
N5	0.0589 (19)	0.0377 (17)	0.0539 (19)	0.0035 (16)	0.0139 (15)	−0.0042 (15)
C12	0.049 (2)	0.059 (3)	0.063 (2)	0.007 (2)	0.0184 (18)	0.015 (2)
C8	0.066 (2)	0.046 (2)	0.067 (3)	−0.011 (2)	0.028 (2)	−0.009 (2)
O21	0.083 (2)	0.073 (2)	0.092 (2)	−0.039 (2)	0.0307 (19)	−0.023 (2)
C7	0.080 (3)	0.039 (2)	0.045 (2)	0.001 (2)	0.0247 (19)	0.0076 (18)
N4	0.080 (3)	0.059 (3)	0.084 (3)	0.003 (2)	0.023 (2)	−0.008 (2)
C16	0.065 (3)	0.068 (3)	0.065 (3)	0.011 (2)	0.027 (2)	0.006 (2)
N6	0.077 (2)	0.048 (2)	0.066 (2)	0.0081 (19)	0.0191 (18)	0.0050 (18)
C3	0.070 (3)	0.055 (3)	0.072 (3)	−0.006 (2)	0.030 (2)	−0.009 (2)
C13	0.058 (3)	0.071 (3)	0.080 (3)	−0.002 (2)	0.024 (2)	0.015 (3)
C14	0.119 (6)	0.065 (4)	0.199 (8)	−0.025 (4)	0.079 (6)	0.000 (5)
C15	0.063 (3)	0.134 (7)	0.153 (7)	−0.020 (4)	−0.002 (4)	0.047 (6)

Geometric parameters (Å, º) top

C2Aa—O1A	1.41 (4)	C17—C16	1.368 (7)
C2Aa—C3	1.52 (5)	C17—H17	0.9300
C2Aa—H2A1	0.9700	N5—N6	1.331 (5)
C2Aa—H2A2	0.9700	N5—N4	1.351 (5)
O1Aa—H1A	0.8200	N5—C8	1.450 (5)
C2Bb—O1B	1.42 (4)	C12—C16	1.389 (7)
C2Bb—C3	1.49 (8)	C12—C13	1.517 (6)
C2Bb—H2B1	0.9700	C8—H8A	0.9700
C2Bb—H2B2	0.9700	C8—H8B	0.9700
O1Bb—H1B	0.8200	C7—N6	1.305 (6)
O19—C20	1.368 (5)	C7—C3	1.343 (7)
O19—C18	1.377 (5)	C7—H7	0.9300
C11—C12	1.378 (6)	N4—C3	1.359 (7)
C11—C10	1.396 (5)	C16—H16	0.9300
C11—H11	0.9300	C13—C14	1.476 (10)
C9—C22	1.335 (6)	C13—C15	1.497 (8)
C9—C10	1.454 (5)	C13—H13	0.9800
C9—C8	1.502 (6)	C14—H14A	0.9600
C10—C18	1.390 (6)	C14—H14B	0.9600
C18—C17	1.378 (6)	C14—H14C	0.9600
C20—O21	1.215 (5)	C15—H15A	0.9600
C20—C22	1.428 (6)	C15—H15B	0.9600
C22—H22	0.9300	C15—H15C	0.9600

O1Aa—C2Aa—C3	107 (4)	C11—C12—C13	122.7 (5)
O1Aa—C2Aa—H2A1	110.3	C16—C12—C13	119.3 (4)
C3—C2Aa—H2A1	110.3	N5—C8—C9	113.1 (3)
O1Aa—C2Aa—H2A2	110.3	N5—C8—H8A	109.0
C3—C2Aa—H2A2	110.3	C9—C8—H8A	109.0
H2A1a—C2Aa—H2A2	108.5	N5—C8—H8B	109.0
C2Aa—O1Aa—H1A	109.5	C9—C8—H8B	109.0
O1Bb—C2Bb—C3	117 (5)	H8A—C8—H8B	107.8
O1Bb—C2Bb—H2B1	108.1	N6—C7—C3	109.3 (4)
C3—C2Bb—H2B1	108.1	N6—C7—H7	125.3
O1Bb—C2Bb—H2B2	108.1	C3—C7—H7	125.3
C3—C2Bb—H2B2	108.1	N5—N4—C3	104.4 (4)
H2B1b—C2Bb—H2B2	107.3	C17—C16—C12	121.7 (4)
C2Bb—O1Bb—H1B	109.5	C17—C16—H16	119.1
C20—O19—C18	121.6 (3)	C12—C16—H16	119.1
C12—C11—C10	122.3 (4)	C7—N6—N5	107.1 (4)
C12—C11—H11	118.9	C7—C3—N4	108.5 (4)
C10—C11—H11	118.9	C7—C3—C2B	125 (3)
C22—C9—C10	119.2 (4)	N4—C3—C2B	126 (3)
C22—C9—C8	123.5 (4)	C7—C3—C2A	120 (2)
C10—C9—C8	117.4 (3)	N4—C3—C2A	132 (2)
C18—C10—C11	117.1 (4)	C14—C13—C15	113.2 (7)
C18—C10—C9	117.5 (4)	C14—C13—C12	113.3 (5)
C11—C10—C9	125.5 (4)	C15—C13—C12	110.9 (5)
O19—C18—C17	116.6 (4)	C14—C13—H13	106.3
O19—C18—C10	121.5 (4)	C15—C13—H13	106.3
C17—C18—C10	121.9 (4)	C12—C13—H13	106.3
O21—C20—O19	116.8 (4)	C13—C14—H14A	109.5
O21—C20—C22	125.8 (4)	C13—C14—H14B	109.5
O19—C20—C22	117.3 (3)	H14A—C14—H14B	109.5
C9—C22—C20	122.9 (4)	C13—C14—H14C	109.5
C9—C22—H22	118.5	H14A—C14—H14C	109.5
C20—C22—H22	118.5	H14B—C14—H14C	109.5
C16—C17—C18	119.0 (5)	C13—C15—H15A	109.5
C16—C17—H17	120.5	C13—C15—H15B	109.5
C18—C17—H17	120.5	H15A—C15—H15B	109.5
N6—N5—N4	110.7 (4)	C13—C15—H15C	109.5
N6—N5—C8	120.1 (3)	H15A—C15—H15C	109.5
N4—N5—C8	129.1 (4)	H15B—C15—H15C	109.5
C11—C12—C16	118.0 (4)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8A···N6ⁱ	0.97	2.55	3.070 (6)	114

Symmetry code: (i) −x, y−1/2, −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].

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