3-Benzyl­idene-6-methoxy­chroman-4-one

Augustine, T.; Vithiya, S.M.; Ramkumar, V.; Kanakam, C.C.

doi:10.1107/S1600536808031541

organic compounds

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ISSN: 2056-9890

Volume 64| Part 11| November 2008| Page o2080

doi:10.1107/S1600536808031541

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3-Benzylidene-6-methoxychroman-4-one

T. Augustine,^a ^* Scholastica Mary Vithiya,^b V. Ramkumar ^c and Charles C. Kanakam ^d

^aDepartment of Chemistry, Presidency College, Chennai, Tamil Nadu, India, ^bDepartment of Chemistry, Auxilium College, Vellore, Tamil Nadu, India, ^cDepartment of Chemistry, Indian Institute of Technology Madras, Chennai 36, Tamil Nadu, India, and ^dDepartment of Chemistry, Valliammai Engineering College, SRM Nagar, Chennai, Tamil Nadu, India
^*Correspondence e-mail: augustineap@gmail.com

(Received 13 September 2008; accepted 30 September 2008; online 9 October 2008)

In the title compound, C₁₇H₁₄O₃, the dihedral angle between the phenyl ring and the benzene ring of the chromanone moiety is 67.78 (3)°. The six-membered heterocyclic ring of the chromanone moiety adopts a half-chair conformation. The structure is stabilized by weak intermolecular C—H⋯O interactions that link the molecules into inversion dimers.

Related literature

For background literature, see: Finch & Tamm (1970 ); Geen et al.(1996 ); Tietze & Gerlitzer (1997 ); Cremer & Pople (1975 ). For a related structure, see: Suresh et al. (2007 ).

Experimental

Crystal data

C₁₇H₁₄O₃
M_r = 266.28
Triclinic, $[P \overline 1]$
a = 7.2678 (2) Å
b = 8.3151 (2) Å
c = 11.7999 (4) Å
α = 95.964 (1)°
β = 103.828 (1)°
γ = 104.042 (1)°
V = 661.74 (3) Å³
Z = 2
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 298 (2) K
0.45 × 0.42 × 0.38 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 1999 ) T_min = 0.960, T_max = 0.966
8868 measured reflections
3041 independent reflections
2404 reflections with I > 2σ(I)
R_int = 0.018

Refinement

R[F² > 2σ(F²)] = 0.039
wR(F²) = 0.116
S = 1.04
3041 reflections
186 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.24 e Å⁻³
Δρ_min = −0.23 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C6—H6⋯O1ⁱ	0.93	2.53	3.4293 (18)	163
Symmetry code: (i) -x, -y+1, -z.

Data collection: APEX2 (Bruker, 2004 ); cell refinement: APEX2 (Bruker, 2004); data reduction: SAINT-Plus (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997 ); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2003 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808031541/fl2222sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808031541/fl2222Isup2.hkl

checkCIF report

Comment top

The chroman-4-one (2,3-dihydro-4-oxo-4H-1-benzopyran) ring system occupies an important position among oxygen heterocyclics and features in a wide variety of compounds of biological and medicinal interest (Finch & Tamm, 1970). Many biologically active natural products containing a chroman ring system have been synthesized via 2-substituted chroman-4-one intermediates including alpha-tocopherol (vitamin E) (Geen et al., 1996). 3-arylidene-4-chromanones have also been isolated as natural products belonging to the class of compounds called homoisoflavonoids(Tietze & Gerlitzer, 1997).

The geometric parameters in the title compound agree with values reported for a similar structure (Suresh et al., 2007). The dihedral angle between the benzene ring of the chromanone moiety and the phenyl ring is 67.78 (3)°. The Chromanone moiety is fused with a six membered heterocyclic ring and the study of torsion angles, asymmetry parameters and least-square plane calculations shows that the chromanone adopts a half chair conformation with a deviation of C14 from the C8/C9/C15/C16/O2 plane by 0.616 (4) Å, Q₂= 0.4053 (14) Å, Q₃= -0.2052 (13)Å, and Q_T=0.4543 (14)Å (Cremer &Pople, (1975). The structure is stabilized by weak intermolecular C—H···O interaction that link the molecules into pairs around a center (Table 1). No other short intermolecular interactions were found.

Related literature top

For background literature, see: Finch & Tamm (1970); Geen et al.(1996); Tietze & Gerlitzer (1997); Cremer & Pople (1975). For a similiar structure, see: Suresh et al. (2007).

Experimental top

Methyl-(2Z)-2-bromo methyl-3-aryl prop-2-enoate (0.006 mole, 1.53 g) was treated with 4-methoxy phenol (0.006 mole, 0.9 ml) in the presence of potassium carbonate in acetone at reflux temperature for 3 hrs. The pure ester, 3-aryl-2-(4-methoxy)-phenoxymethylprop-2-enoate was obtained after purifying it using silica gel and column chromatography (3% ethyl acetate - hexane). Hydrolysis of this ester was carried out with KOH in aqueous 1,4–dioxane at room temperature. The reaction mixture was acidified and the precipitated acid was purified by recrystalization. Finally the acid was treated with triflouroacetic anhydride and the reaction mixture was refluxed in dichloro- methane for 1 hr. It was further purified by column chromatography (silica gel-3% ethyl acetate - hexane) and the crystals used for data collection were obtained by slow evaporation from methanol.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT-Plus (Bruker, 2004); data reduction: SAINT-Plus (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2003).

Figures top

Fig. 1. ORTEP of the molecule with atoms represented as 30% probability ellipsoids.

3-Benzylidene-6-methoxychroman-4-one top

Crystal data top

C₁₇H₁₄O₃	Z = 2
M_r = 266.28	F(000) = 280
Triclinic, P1	D_x = 1.336 Mg m⁻³
Hall symbol: -p 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.2678 (2) Å	Cell parameters from 4851 reflections
b = 8.3151 (2) Å	θ = 2.6–28.3°
c = 11.7999 (4) Å	µ = 0.09 mm⁻¹
α = 95.964 (1)°	T = 298 K
β = 103.828 (1)°	Block, colourless
γ = 104.042 (1)°	0.45 × 0.42 × 0.38 mm
V = 661.74 (3) Å³

Data collection top

Bruker APEXII CCD area-detector diffractometer	3041 independent reflections
Radiation source: fine-focus sealed tube	2404 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.018
ϕ and ω scans	θ_max = 28.3°, θ_min = 2.6°
Absorption correction: multi-scan (SADABS; Bruker, 1999)	h = −8→9
T_min = 0.960, T_max = 0.966	k = −10→11
8868 measured reflections	l = −15→15

Refinement top

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)] = 0.039	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.116	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	w = 1/[σ²(F_o²) + (0.0554P)² + 0.1403P] where P = (F_o² + 2F_c²)/3
3041 reflections	(Δ/σ)_max < 0.001
186 parameters	Δρ_max = 0.25 e Å⁻³
0 restraints	Δρ_min = −0.23 e Å⁻³

Crystal data top

C₁₇H₁₄O₃	γ = 104.042 (1)°
M_r = 266.28	V = 661.74 (3) Å³
Triclinic, P1	Z = 2
a = 7.2678 (2) Å	Mo Kα radiation
b = 8.3151 (2) Å	µ = 0.09 mm⁻¹
c = 11.7999 (4) Å	T = 298 K
α = 95.964 (1)°	0.45 × 0.42 × 0.38 mm
β = 103.828 (1)°

Data collection top

Bruker APEXII CCD area-detector diffractometer	3041 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 1999)	2404 reflections with I > 2σ(I)
T_min = 0.960, T_max = 0.966	R_int = 0.018
8868 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.039	0 restraints
wR(F²) = 0.116	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	Δρ_max = 0.25 e Å⁻³
3041 reflections	Δρ_min = −0.23 e Å⁻³
186 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.

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.

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

	x	y	z	U_iso*/U_eq
C1	−0.38800 (18)	0.42099 (15)	0.12980 (11)	0.0357 (3)
C2	−0.49675 (19)	0.45875 (16)	0.20631 (12)	0.0413 (3)
H2	−0.4480	0.5584	0.2610	0.050*
C3	−0.6764 (2)	0.34969 (18)	0.20189 (13)	0.0469 (3)
H3	−0.7484	0.3771	0.2527	0.056*
C4	−0.7491 (2)	0.20056 (18)	0.12250 (14)	0.0499 (3)
H4	−0.8689	0.1265	0.1205	0.060*
C5	−0.6433 (2)	0.16181 (18)	0.04615 (13)	0.0526 (4)
H5	−0.6916	0.0606	−0.0069	0.063*
C6	−0.4668 (2)	0.27146 (17)	0.04756 (12)	0.0448 (3)
H6	−0.3995	0.2458	−0.0066	0.054*
C7	−0.19833 (18)	0.53387 (16)	0.12988 (12)	0.0384 (3)
C8	−0.04981 (18)	0.62292 (15)	0.22311 (11)	0.0366 (3)
C9	0.12813 (18)	0.73207 (16)	0.20106 (11)	0.0375 (3)
C10	0.47891 (18)	0.89529 (15)	0.29540 (11)	0.0370 (3)
H10	0.4781	0.9476	0.2294	0.044*
C11	0.64996 (18)	0.92856 (15)	0.38626 (11)	0.0390 (3)
C12	0.65136 (19)	0.84577 (17)	0.48305 (12)	0.0439 (3)
H12	0.7679	0.8659	0.5429	0.053*
C13	0.4833 (2)	0.73495 (18)	0.49135 (12)	0.0439 (3)
H13	0.4862	0.6800	0.5562	0.053*
C14	−0.03927 (19)	0.62083 (18)	0.35174 (11)	0.0427 (3)
H14A	−0.0509	0.7271	0.3874	0.051*
H14B	−0.1486	0.5319	0.3584	0.051*
C15	0.30664 (17)	0.78222 (14)	0.30322 (10)	0.0336 (3)
C16	0.30814 (18)	0.70497 (15)	0.40210 (11)	0.0362 (3)
C17	0.8268 (3)	1.1358 (3)	0.29888 (18)	0.0764 (6)
H17A	0.8124	1.0644	0.2261	0.115*
H17B	0.9493	1.2225	0.3186	0.115*
H17C	0.7195	1.1861	0.2896	0.115*
O1	0.13097 (14)	0.77364 (14)	0.10531 (9)	0.0566 (3)
O2	0.14409 (13)	0.59397 (12)	0.41471 (8)	0.0454 (2)
O3	0.82540 (14)	1.03993 (13)	0.38987 (9)	0.0540 (3)
H7	−0.175 (2)	0.5435 (19)	0.0546 (15)	0.051 (4)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0311 (6)	0.0373 (6)	0.0357 (6)	0.0073 (5)	0.0046 (5)	0.0092 (5)
C2	0.0344 (6)	0.0382 (6)	0.0475 (7)	0.0079 (5)	0.0088 (5)	0.0016 (5)
C3	0.0365 (7)	0.0516 (8)	0.0538 (8)	0.0108 (6)	0.0158 (6)	0.0100 (6)
C4	0.0349 (7)	0.0470 (7)	0.0587 (9)	−0.0018 (6)	0.0082 (6)	0.0122 (6)
C5	0.0497 (8)	0.0431 (7)	0.0504 (8)	−0.0009 (6)	0.0048 (6)	−0.0030 (6)
C6	0.0426 (7)	0.0480 (7)	0.0384 (7)	0.0072 (6)	0.0091 (5)	0.0016 (5)
C7	0.0339 (6)	0.0423 (6)	0.0378 (6)	0.0081 (5)	0.0092 (5)	0.0087 (5)
C8	0.0310 (6)	0.0403 (6)	0.0380 (6)	0.0084 (5)	0.0097 (5)	0.0074 (5)
C9	0.0321 (6)	0.0423 (6)	0.0353 (6)	0.0069 (5)	0.0071 (5)	0.0079 (5)
C10	0.0331 (6)	0.0381 (6)	0.0375 (6)	0.0086 (5)	0.0064 (5)	0.0066 (5)
C11	0.0297 (6)	0.0386 (6)	0.0444 (7)	0.0081 (5)	0.0059 (5)	0.0025 (5)
C12	0.0347 (7)	0.0539 (8)	0.0385 (7)	0.0150 (6)	0.0006 (5)	0.0039 (6)
C13	0.0413 (7)	0.0551 (8)	0.0352 (6)	0.0154 (6)	0.0067 (5)	0.0111 (5)
C14	0.0321 (6)	0.0548 (8)	0.0392 (7)	0.0076 (6)	0.0114 (5)	0.0059 (6)
C15	0.0298 (6)	0.0357 (6)	0.0334 (6)	0.0087 (5)	0.0067 (5)	0.0032 (4)
C16	0.0334 (6)	0.0401 (6)	0.0349 (6)	0.0101 (5)	0.0100 (5)	0.0047 (5)
C17	0.0437 (9)	0.0871 (13)	0.0821 (13)	−0.0091 (9)	0.0049 (8)	0.0372 (10)
O1	0.0392 (5)	0.0764 (7)	0.0416 (5)	−0.0049 (5)	0.0035 (4)	0.0223 (5)
O2	0.0369 (5)	0.0580 (6)	0.0403 (5)	0.0077 (4)	0.0104 (4)	0.0173 (4)
O3	0.0305 (5)	0.0574 (6)	0.0614 (6)	−0.0006 (4)	−0.0003 (4)	0.0152 (5)

Geometric parameters (Å, º) top

C1—C2	1.3932 (18)	C10—C11	1.3805 (17)
C1—C6	1.3978 (17)	C10—C15	1.4007 (17)
C1—C7	1.4671 (17)	C10—H10	0.9300
C2—C3	1.3830 (19)	C11—O3	1.3704 (15)
C2—H2	0.9300	C11—C12	1.3927 (19)
C3—C4	1.378 (2)	C12—C13	1.371 (2)
C3—H3	0.9300	C12—H12	0.9300
C4—C5	1.377 (2)	C13—C16	1.3938 (17)
C4—H4	0.9300	C13—H13	0.9300
C5—C6	1.377 (2)	C14—O2	1.4434 (16)
C5—H5	0.9300	C14—H14A	0.9700
C6—H6	0.9300	C14—H14B	0.9700
C7—C8	1.3412 (17)	C15—C16	1.3883 (17)
C7—H7	0.950 (16)	C16—O2	1.3693 (15)
C8—C9	1.4846 (18)	C17—O3	1.403 (2)
C8—C14	1.5036 (18)	C17—H17A	0.9600
C9—O1	1.2187 (15)	C17—H17B	0.9600
C9—C15	1.4818 (16)	C17—H17C	0.9600

C2—C1—C6	118.20 (12)	O3—C11—C10	124.75 (12)
C2—C1—C7	122.70 (11)	O3—C11—C12	115.45 (11)
C6—C1—C7	119.07 (12)	C10—C11—C12	119.80 (12)
C3—C2—C1	120.72 (12)	C13—C12—C11	120.93 (12)
C3—C2—H2	119.6	C13—C12—H12	119.5
C1—C2—H2	119.6	C11—C12—H12	119.5
C4—C3—C2	120.26 (13)	C12—C13—C16	119.70 (12)
C4—C3—H3	119.9	C12—C13—H13	120.1
C2—C3—H3	119.9	C16—C13—H13	120.1
C5—C4—C3	119.63 (13)	O2—C14—C8	111.15 (10)
C5—C4—H4	120.2	O2—C14—H14A	109.4
C3—C4—H4	120.2	C8—C14—H14A	109.4
C6—C5—C4	120.64 (13)	O2—C14—H14B	109.4
C6—C5—H5	119.7	C8—C14—H14B	109.4
C4—C5—H5	119.7	H14A—C14—H14B	108.0
C5—C6—C1	120.49 (13)	C16—C15—C10	120.07 (11)
C5—C6—H6	119.8	C16—C15—C9	119.69 (11)
C1—C6—H6	119.8	C10—C15—C9	119.96 (11)
C8—C7—C1	128.33 (12)	O2—C16—C15	122.60 (11)
C8—C7—H7	115.3 (9)	O2—C16—C13	117.53 (11)
C1—C7—H7	116.4 (9)	C15—C16—C13	119.83 (12)
C7—C8—C9	118.66 (11)	O3—C17—H17A	109.5
C7—C8—C14	126.65 (12)	O3—C17—H17B	109.5
C9—C8—C14	114.65 (10)	H17A—C17—H17B	109.5
O1—C9—C15	121.81 (11)	O3—C17—H17C	109.5
O1—C9—C8	123.09 (11)	H17A—C17—H17C	109.5
C15—C9—C8	115.06 (11)	H17B—C17—H17C	109.5
C11—C10—C15	119.58 (12)	C16—O2—C14	113.85 (10)
C11—C10—H10	120.2	C11—O3—C17	117.35 (11)
C15—C10—H10	120.2

C6—C1—C2—C3	0.93 (19)	C11—C12—C13—C16	−0.3 (2)
C7—C1—C2—C3	179.01 (12)	C7—C8—C14—O2	129.37 (13)
C1—C2—C3—C4	0.9 (2)	C9—C8—C14—O2	−48.50 (15)
C2—C3—C4—C5	−1.0 (2)	C11—C10—C15—C16	0.33 (18)
C3—C4—C5—C6	−0.7 (2)	C11—C10—C15—C9	−173.63 (11)
C4—C5—C6—C1	2.6 (2)	O1—C9—C15—C16	−166.84 (12)
C2—C1—C6—C5	−2.7 (2)	C8—C9—C15—C16	10.83 (17)
C7—C1—C6—C5	179.18 (12)	O1—C9—C15—C10	7.14 (19)
C2—C1—C7—C8	41.2 (2)	C8—C9—C15—C10	−175.19 (10)
C6—C1—C7—C8	−140.74 (14)	C10—C15—C16—O2	179.75 (11)
C1—C7—C8—C9	−178.86 (12)	C9—C15—C16—O2	−6.28 (18)
C1—C7—C8—C14	3.3 (2)	C10—C15—C16—C13	−2.59 (18)
C7—C8—C9—O1	16.3 (2)	C9—C15—C16—C13	171.39 (11)
C14—C8—C9—O1	−165.66 (13)	C12—C13—C16—O2	−179.65 (11)
C7—C8—C9—C15	−161.35 (11)	C12—C13—C16—C15	2.57 (19)
C14—C8—C9—C15	16.71 (16)	C15—C16—O2—C14	−27.22 (16)
C15—C10—C11—O3	−178.13 (11)	C13—C16—O2—C14	155.06 (11)
C15—C10—C11—C12	1.94 (18)	C8—C14—O2—C16	53.73 (14)
O3—C11—C12—C13	178.09 (12)	C10—C11—O3—C17	5.0 (2)
C10—C11—C12—C13	−2.0 (2)	C12—C11—O3—C17	−175.11 (15)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C6—H6···O1ⁱ	0.93	2.53	3.4293 (18)	163

Symmetry code: (i) −x, −y+1, −z.

Experimental details

Crystal data
Chemical formula	C₁₇H₁₄O₃
M_r	266.28
Crystal system, space group	Triclinic, P1
Temperature (K)	298
a, b, c (Å)	7.2678 (2), 8.3151 (2), 11.7999 (4)
α, β, γ (°)	95.964 (1), 103.828 (1), 104.042 (1)
V (Å³)	661.74 (3)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.45 × 0.42 × 0.38

Data collection
Diffractometer	Bruker APEXII CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 1999)
T_min, T_max	0.960, 0.966
No. of measured, independent and observed [I > 2σ(I)] reflections	8868, 3041, 2404
R_int	0.018
(sin θ/λ)_max (Å⁻¹)	0.667

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.039, 0.116, 1.04
No. of reflections	3041
No. of parameters	186
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.25, −0.23

Computer programs: APEX2 (Bruker, 2004), SAINT-Plus (Bruker, 2004), SHELXS97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2003).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C6—H6···O1ⁱ	0.93	2.53	3.4293 (18)	163

Symmetry code: (i) −x, −y+1, −z.

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Volume 64| Part 11| November 2008| Page o2080

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