Crystal structure of 3-[2-(4-methyl­phen­yl)ethyn­yl]-2H-chromen-2-one

Caracelli, I.; Maganhi, S.H.; Stefani, H.A.; Gueogjian, K.; Tiekink, E.R.T.

doi:10.1107/S2056989014027790

organic compounds

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ISSN: 2056-9890

Volume 71| Part 2| February 2015| Pages o90-o91

doi:10.1107/S2056989014027790

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Crystal structure of 3-[2-(4-methylphenyl)ethynyl]-2H-chromen-2-one

Ignez Caracelli,^a ^* Stella H. Maganhi,^a Hélio A. Stefani,^b Karina Gueogjian ^b and Edward R. T. Tiekink ^c

^aDepartmento de Física, Universidade Federal de São Carlos, 13565-905 São Carlos, SP, Brazil, ^bDepartamento de Farmácia, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, 05508-900 São Paulo-SP, Brazil, and ^cDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
^*Correspondence e-mail: ignez@ufscar.br

Edited by P. C. Healy, Griffith University, Australia (Received 15 December 2014; accepted 20 December 2014; online 10 January 2015)

The coumarin ring system in the title asymmetric alkyne, C₁₈H₁₂O₂, is approximately planar (r.m.s. deviation of the 11 non-H atoms = 0.048 Å), and is inclined with respect to the methylbenzene ring, forming a dihedral angle of 33.68 (4)°. In the crystal, supramolecular zigzag chains along the c-axis direction are formed via weak C—H⋯O hydrogen bonds, and these are connected into double layers via weak C—H⋯π interactions; these stack along the a axis.

Keywords: crystal structure; coumarins; asymmetric alkyne; hydrogen bonding; C—H⋯π interactions.

CCDC reference: 1040558

1. Related literature

For the biological activity of coumarins, see: Wu et al. (2009 ). For background to previous work on coumarins, see: Stefani et al. (2012 ). For a related structure, see: Elangovan et al. (2004 ). For synthetic details, see: Gueogjian (2011 ).

2. Experimental

2.1. Crystal data

C₁₈H₁₂O₂
M_r = 260.28
Monoclinic, P 2₁ /c
a = 8.4695 (2) Å
b = 10.6759 (2) Å
c = 14.5208 (2) Å
β = 98.093 (2)°
V = 1299.89 (4) Å³
Z = 4
Cu Kα radiation
μ = 0.69 mm⁻¹
T = 100 K
0.30 × 0.25 × 0.20 mm

2.2. Data collection

Agilent CCD diffratcometer diffractometer
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011 ) T_min = 0.834, T_max = 1.000
5023 measured reflections
2664 independent reflections
2416 reflections with I > 2σ(I)
R_int = 0.015

2.3. Refinement

R[F² > 2σ(F²)] = 0.038
wR(F²) = 0.105
S = 1.04
2664 reflections
182 parameters
H-atom parameters constrained
Δρ_max = 0.25 e Å⁻³
Δρ_min = −0.21 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 and Cg2 are the centroids of the C4–C9 and C12–C17 rings, respectively.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C7—H7⋯O2ⁱ	0.95	2.48	3.1425 (14)	127
C13—H13⋯Cg1ⁱⁱ	0.95	2.94	3.4416 (12)	115
C5—H5⋯Cg2ⁱⁱⁱ	0.95	3.00	3.7780 (13)	140
Symmetry codes: (i) $[x, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]$ ; (ii) -x, -y+1, -z+1; (iii) $[x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ .

Data collection: CrysAlis PRO (Agilent, 2011); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SIR2014 (Burla et al., 2015 ); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2008 ); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012 ) and DIAMOND (Brandenburg, 2006 ); software used to prepare material for publication: MarvinSketch (ChemAxon, 2010 ) and publCIF (Westrip, 2010 ).

Supporting information

CCDC reference: 1040558

Crystal structure: contains datablocks I, New_Global_Publ_Block. DOI: 10.1107/S2056989014027790/hg5424sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S2056989014027790/hg5424Isup2.hkl

Supporting information file. DOI: 10.1107/S2056989014027790/hg5424Isup3.cml

checkCIF report

Introduction top

Coumarins are heterocycles presenting a wide range of different biological activities (Wu et al., 2009). As part of our on-going interest in the synthesis of coumarin derivatives with biological activity (Stefani et al., 2012) the title compound was synthesized.

Experimental top

Synthesis and crystallization top

The title compound was prepared as per Gueogjian (2011). 3-Bromo coumarin (112.5 mg, 0.5 mmol), potassium trifluoroborate salt (0.55 mmol), PdCl₂(dppf).CH₂Cl₂ (41 mg, 10 mol%), i-Pr₂NEt (0.3 mL, 1.5 mmol)and 1,4-dioxane/H₂O (2/1, 3 mL), in acetonitrile (20 mL) were added to a two-necked round-bottomed flask equipped with a reflux condenser under N₂. The reaction mixture was heated under reflux at 353 K, and was monitored by TLC and GC analysis. After the consumption of the 3-bromocoumarin, the mixture was extracted twice with ethyl acetate (50 mL). The organic phase was separated, dried over MgSO₄ and concentrated under vacuum. The residue was purified by flash chromatography (ethyl acetate/hexane 10:90). The title compound was obtained as a brown solid in 70% yield. Suitable crystals were obtained by slow evaporation from ethyl acetate/hexane.

Refinement top

Carbon-bound H-atoms were placed in calculated positions (C—H = 0.95 to 0.98 Å) and were included in the refinement in the riding model approximation, with U_iso(H) = 1.2–1.5U_eq(C).

Results and discussion top

The title compound, Fig. 1, is an asymmetric alkyne. The coumarin residue is approximately planar with the r.m.s. deviation of the 11 non-hydrogen atoms being 0.048 Å; the maximum deviations from their least-squares plane are 0.078 (1) and -0.066 (1) Å for the C2 and O2 atoms, respectively. Overall, the molecule is non-planar as seen in the dihedral between the fused ring system and the methylbenzene ring of 33.68 (4)°.

The most closely related structure in the literature is of the derivative where the methyl group of the title compound has been replaced by an isopropoxy group (Elangovan et al., 2004). In this case, with the exception of the terminal methyl groups, the molecule is planar with the dihedral angle between the 11 non-hydrogen atoms of the courmarin residue the benzene ring being 0.88 (6)°.

Weak coumarin-C₆—C—H···O(exocyclic) hydrogen bonding gives rise to a supramolecular chain aligned along the c axis, Table 1 and Fig. 2. The chains are connected into double layers, sustained by weak C—H···π interactions, that stack along the a axis with no specific interactions between them, Table 2 and Fig. 3.

Related literature top

For the biological activity of coumarins, see: Wu et al. (2009). For background to previous work on coumarins, see: Stefani et al. (2012). For a related structure, see: Elangovan et al. (2004). For synthetic details, see: Gueogjian (2011).

Computing details top

Data collection: CrysAlis PRO (Agilent, 2011); cell refinement: CrysAlis PRO (Agilent, 2011); data reduction: CrysAlis PRO (Agilent, 2011); program(s) used to solve structure: SIR2014 (Burla et al., 2015); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: MarvinSketch (ChemAxon, 2010) and publCIF (Westrip, 2010).

Figures top

	Fig. 1. The molecular structure of the title compound showing the atom-labelling scheme and displacement ellipsoids at the 70% probability level.
	Fig. 2. A view of the zigzag supramolecular sustained by weak C—H···O hydrogen bonds (orange dashed lines) and aligned along the c axis in the crystal packing.
	Fig. 3. A view in projection down the c axis of the unit-cell contents. The weak C—H···O and C—H···π interactions are shown as orange and purple dashed lines, respectively.

3-[2-(4-Methylphenyl)ethynyl]-2H-chromen-2-one top

Crystal data top

C₁₈H₁₂O₂	F(000) = 544
M_r = 260.28	D_x = 1.330 Mg m⁻³
Monoclinic, P2₁/c	Cu Kα radiation, λ = 1.54184 Å
a = 8.4695 (2) Å	Cell parameters from 3107 reflections
b = 10.6759 (2) Å	θ = 3.1–76.1°
c = 14.5208 (2) Å	µ = 0.69 mm⁻¹
β = 98.093 (2)°	T = 100 K
V = 1299.89 (4) Å³	Prism, dark orange
Z = 4	0.30 × 0.25 × 0.20 mm

Data collection top

Agilent CCD diffratcometer diffractometer	2416 reflections with I > 2σ(I)
Radiation source: SuperNova (Cu) X-ray Source	R_int = 0.015
ω scans	θ_max = 76.3°, θ_min = 5.2°
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011)	h = −9→10
T_min = 0.834, T_max = 1.000	k = −6→13
5023 measured reflections	l = −17→18
2664 independent reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.038	H-atom parameters constrained
wR(F²) = 0.105	w = 1/[σ²(F_o²) + (0.0605P)² + 0.3358P] where P = (F_o² + 2F_c²)/3
S = 1.04	(Δ/σ)_max < 0.001
2664 reflections	Δρ_max = 0.25 e Å⁻³
182 parameters	Δρ_min = −0.21 e Å⁻³
0 restraints

Crystal data top

C₁₈H₁₂O₂	V = 1299.89 (4) Å³
M_r = 260.28	Z = 4
Monoclinic, P2₁/c	Cu Kα radiation
a = 8.4695 (2) Å	µ = 0.69 mm⁻¹
b = 10.6759 (2) Å	T = 100 K
c = 14.5208 (2) Å	0.30 × 0.25 × 0.20 mm
β = 98.093 (2)°

Data collection top

Agilent CCD diffratcometer diffractometer	2664 independent reflections
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011)	2416 reflections with I > 2σ(I)
T_min = 0.834, T_max = 1.000	R_int = 0.015
5023 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.038	0 restraints
wR(F²) = 0.105	H-atom parameters constrained
S = 1.04	Δρ_max = 0.25 e Å⁻³
2664 reflections	Δρ_min = −0.21 e Å⁻³
182 parameters

Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O1	0.13803 (10)	0.67272 (7)	0.66818 (5)	0.0210 (2)
O2	0.15964 (12)	0.72775 (8)	0.52430 (6)	0.0313 (2)
C1	0.16397 (14)	0.64322 (11)	0.57962 (7)	0.0211 (2)
C2	0.19557 (13)	0.51127 (11)	0.56003 (7)	0.0199 (2)
C3	0.18389 (13)	0.42253 (10)	0.62585 (7)	0.0199 (2)
H3	0.1980	0.3368	0.6115	0.024*
C4	0.15055 (13)	0.45668 (10)	0.71666 (7)	0.0184 (2)
C5	0.14038 (13)	0.36959 (11)	0.78810 (8)	0.0206 (2)
H5	0.1504	0.2826	0.7763	0.025*
C6	0.11585 (13)	0.40976 (11)	0.87544 (8)	0.0217 (2)
H6	0.1078	0.3504	0.9233	0.026*
C7	0.10299 (13)	0.53744 (11)	0.89331 (7)	0.0213 (2)
H7	0.0880	0.5645	0.9538	0.026*
C8	0.11176 (13)	0.62546 (11)	0.82380 (7)	0.0204 (2)
H8	0.1033	0.7124	0.8360	0.025*
C9	0.13313 (13)	0.58337 (10)	0.73620 (7)	0.0181 (2)
C10	0.24056 (14)	0.48424 (11)	0.47093 (8)	0.0219 (2)
C11	0.28627 (14)	0.46381 (11)	0.39787 (8)	0.0213 (2)
C12	0.34093 (13)	0.43519 (11)	0.31108 (7)	0.0191 (2)
C13	0.28464 (13)	0.50208 (11)	0.23036 (8)	0.0214 (2)
H13	0.2132	0.5701	0.2333	0.026*
C14	0.33248 (14)	0.46968 (12)	0.14599 (8)	0.0227 (3)
H14	0.2941	0.5166	0.0919	0.027*
C15	0.43582 (13)	0.36949 (11)	0.13914 (8)	0.0215 (2)
C16	0.49343 (14)	0.30434 (11)	0.22028 (8)	0.0229 (2)
H16	0.5653	0.2366	0.2172	0.027*
C17	0.44814 (14)	0.33623 (11)	0.30511 (8)	0.0218 (2)
H17	0.4897	0.2910	0.3595	0.026*
C18	0.48231 (15)	0.32959 (13)	0.04694 (8)	0.0286 (3)
H18A	0.4267	0.3821	−0.0027	0.043*
H18B	0.4526	0.2417	0.0351	0.043*
H18C	0.5978	0.3390	0.0486	0.043*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0288 (4)	0.0177 (4)	0.0170 (4)	0.0023 (3)	0.0054 (3)	0.0017 (3)
O2	0.0459 (6)	0.0265 (5)	0.0239 (4)	0.0070 (4)	0.0132 (4)	0.0074 (3)
C1	0.0237 (6)	0.0236 (6)	0.0164 (5)	0.0020 (4)	0.0046 (4)	0.0019 (4)
C2	0.0189 (5)	0.0235 (6)	0.0170 (5)	0.0023 (4)	0.0016 (4)	−0.0011 (4)
C3	0.0198 (5)	0.0201 (5)	0.0195 (5)	0.0020 (4)	0.0018 (4)	−0.0012 (4)
C4	0.0168 (5)	0.0201 (5)	0.0179 (5)	0.0009 (4)	0.0009 (4)	0.0001 (4)
C5	0.0202 (5)	0.0193 (5)	0.0217 (5)	0.0006 (4)	0.0008 (4)	0.0021 (4)
C6	0.0211 (5)	0.0252 (6)	0.0182 (5)	−0.0015 (4)	0.0003 (4)	0.0051 (4)
C7	0.0205 (5)	0.0282 (6)	0.0148 (5)	−0.0019 (4)	0.0007 (4)	−0.0009 (4)
C8	0.0216 (5)	0.0207 (5)	0.0187 (5)	−0.0006 (4)	0.0018 (4)	−0.0017 (4)
C9	0.0183 (5)	0.0194 (5)	0.0163 (5)	0.0001 (4)	0.0013 (4)	0.0023 (4)
C10	0.0223 (5)	0.0241 (5)	0.0189 (5)	0.0014 (4)	0.0018 (4)	−0.0002 (4)
C11	0.0213 (5)	0.0226 (5)	0.0197 (5)	−0.0006 (4)	0.0013 (4)	−0.0009 (4)
C12	0.0191 (5)	0.0214 (5)	0.0169 (5)	−0.0036 (4)	0.0027 (4)	−0.0027 (4)
C13	0.0196 (5)	0.0231 (6)	0.0209 (5)	0.0012 (4)	0.0013 (4)	−0.0014 (4)
C14	0.0218 (5)	0.0292 (6)	0.0164 (5)	−0.0008 (5)	−0.0006 (4)	0.0012 (4)
C15	0.0191 (5)	0.0278 (6)	0.0178 (5)	−0.0054 (4)	0.0030 (4)	−0.0048 (4)
C16	0.0211 (5)	0.0231 (6)	0.0250 (6)	0.0013 (4)	0.0053 (4)	−0.0022 (4)
C17	0.0229 (5)	0.0238 (6)	0.0184 (5)	−0.0002 (4)	0.0021 (4)	0.0023 (4)
C18	0.0274 (6)	0.0394 (7)	0.0200 (6)	−0.0036 (5)	0.0062 (5)	−0.0074 (5)

Geometric parameters (Å, º) top

O1—C1	1.3713 (13)	C8—H8	0.9500
O1—C9	1.3780 (13)	C10—C11	1.1995 (16)
O2—C1	1.2053 (14)	C11—C12	1.4353 (15)
C1—C2	1.4691 (16)	C12—C13	1.3978 (16)
C2—C3	1.3592 (15)	C12—C17	1.4036 (16)
C2—C10	1.4287 (15)	C13—C14	1.3873 (15)
C3—C4	1.4339 (14)	C13—H13	0.9500
C3—H3	0.9500	C14—C15	1.3945 (17)
C4—C9	1.3941 (15)	C14—H14	0.9500
C4—C5	1.4048 (15)	C15—C16	1.3958 (16)
C5—C6	1.3820 (15)	C15—C18	1.5090 (14)
C5—H5	0.9500	C16—C17	1.3833 (15)
C6—C7	1.3946 (17)	C16—H16	0.9500
C6—H6	0.9500	C17—H17	0.9500
C7—C8	1.3887 (16)	C18—H18A	0.9800
C7—H7	0.9500	C18—H18B	0.9800
C8—C9	1.3847 (15)	C18—H18C	0.9800

C1—O1—C9	122.56 (9)	C8—C9—C4	122.22 (10)
O2—C1—O1	117.33 (10)	C11—C10—C2	176.53 (12)
O2—C1—C2	125.32 (10)	C10—C11—C12	178.19 (12)
O1—C1—C2	117.35 (9)	C13—C12—C17	118.68 (10)
C3—C2—C10	123.44 (11)	C13—C12—C11	120.89 (10)
C3—C2—C1	119.92 (10)	C17—C12—C11	120.39 (10)
C10—C2—C1	116.62 (10)	C14—C13—C12	120.37 (11)
C2—C3—C4	120.84 (10)	C14—C13—H13	119.8
C2—C3—H3	119.6	C12—C13—H13	119.8
C4—C3—H3	119.6	C13—C14—C15	121.24 (10)
C9—C4—C5	118.20 (10)	C13—C14—H14	119.4
C9—C4—C3	118.30 (10)	C15—C14—H14	119.4
C5—C4—C3	123.46 (10)	C14—C15—C16	118.05 (10)
C6—C5—C4	120.34 (11)	C14—C15—C18	121.64 (11)
C6—C5—H5	119.8	C16—C15—C18	120.29 (11)
C4—C5—H5	119.8	C17—C16—C15	121.42 (11)
C5—C6—C7	119.99 (10)	C17—C16—H16	119.3
C5—C6—H6	120.0	C15—C16—H16	119.3
C7—C6—H6	120.0	C16—C17—C12	120.21 (10)
C8—C7—C6	120.84 (10)	C16—C17—H17	119.9
C8—C7—H7	119.6	C12—C17—H17	119.9
C6—C7—H7	119.6	C15—C18—H18A	109.5
C9—C8—C7	118.38 (10)	C15—C18—H18B	109.5
C9—C8—H8	120.8	H18A—C18—H18B	109.5
C7—C8—H8	120.8	C15—C18—H18C	109.5
O1—C9—C8	117.06 (10)	H18A—C18—H18C	109.5
O1—C9—C4	120.72 (9)	H18B—C18—H18C	109.5

C9—O1—C1—O2	177.09 (10)	C7—C8—C9—O1	178.68 (9)
C9—O1—C1—C2	−3.21 (15)	C7—C8—C9—C4	−1.88 (17)
O2—C1—C2—C3	−174.34 (12)	C5—C4—C9—O1	−178.37 (9)
O1—C1—C2—C3	5.98 (16)	C3—C4—C9—O1	3.95 (16)
O2—C1—C2—C10	6.73 (18)	C5—C4—C9—C8	2.21 (16)
O1—C1—C2—C10	−172.95 (10)	C3—C4—C9—C8	−175.47 (10)
C10—C2—C3—C4	175.00 (10)	C17—C12—C13—C14	0.91 (16)
C1—C2—C3—C4	−3.86 (17)	C11—C12—C13—C14	−176.91 (10)
C2—C3—C4—C9	−1.08 (16)	C12—C13—C14—C15	0.70 (17)
C2—C3—C4—C5	−178.62 (10)	C13—C14—C15—C16	−1.63 (17)
C9—C4—C5—C6	−0.84 (16)	C13—C14—C15—C18	177.00 (11)
C3—C4—C5—C6	176.70 (10)	C14—C15—C16—C17	0.99 (17)
C4—C5—C6—C7	−0.77 (17)	C18—C15—C16—C17	−177.67 (10)
C5—C6—C7—C8	1.12 (17)	C15—C16—C17—C12	0.60 (18)
C6—C7—C8—C9	0.18 (17)	C13—C12—C17—C16	−1.54 (17)
C1—O1—C9—C8	177.74 (10)	C11—C12—C17—C16	176.28 (10)
C1—O1—C9—C4	−1.71 (16)

Hydrogen-bond geometry (Å, º) top

Cg1 and Cg2 are the centroids of the C4–C9 and C12–C17 rings, respectively.

D—H···A	D—H	H···A	D···A	D—H···A
C7—H7···O2ⁱ	0.95	2.48	3.1425 (14)	127
C13—H13···Cg1ⁱⁱ	0.95	2.94	3.4416 (12)	115
C5—H5···Cg2ⁱⁱⁱ	0.95	3.00	3.7780 (13)	140

Symmetry codes: (i) x, −y+3/2, z+1/2; (ii) −x, −y+1, −z+1; (iii) x, −y+1/2, z+1/2.

Hydrogen-bond geometry (Å, º) top

Cg1 and Cg2 are the centroids of the C4–C9 and C12–C17 rings, respectively.

D—H···A	D—H	H···A	D···A	D—H···A
C7—H7···O2ⁱ	0.95	2.48	3.1425 (14)	127
C13—H13···Cg1ⁱⁱ	0.95	2.94	3.4416 (12)	115
C5—H5···Cg2ⁱⁱⁱ	0.95	3.00	3.7780 (13)	140

Symmetry codes: (i) x, −y+3/2, z+1/2; (ii) −x, −y+1, −z+1; (iii) x, −y+1/2, z+1/2.

Acknowledgements

The Brazilian agencies CNPq (306121/2013–2 to IC and 308320/2010–7 to HAS), FAPESP and CAPES are acknowledged for financial support.

References

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Volume 71| Part 2| February 2015| Pages o90-o91

doi:10.1107/S2056989014027790

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