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Acta Cryst. (2009). E65, o128    [ doi:10.1107/S1600536808042074 ]

3-(4-Methoxyphenyl)-1H-isochromen-1-one

T. Maiyalagan, V. R. Hathwar, P. Manivel, N. B. Arslan and F. N. Khan

Abstract top

The asymmetric unit of the title compound, C16H12O3, contains two crystallographically independent molecules. The isochromene ring system is planar (maximum deviation 0.024 Å) and is oriented at dihedral angles of 2.63 (3) and 0.79 (3)° with respect to the methoxybenzene rings in the two independent molecules.

Comment top

Isochromenones are structurally related to the chromenones, (Hill, 1986). They have a wide range of biological activities (Hill, 1986; Canendo et al., 1997; Whyte et al., 1996). Isocoumarins (Barry, 1964) are also useful intermediates in the synthesis of a variety of important compounds including some carbocyclic and heterocyclic compounds. In view of their natural occurrence, biological activities and utility as synthetic intermediates, we have synthesized the title compound, and reported herein its crystal structure.

The asymmetric unit of the title compound contains two crystallographically independent molecules of similar geometry. The dihedral angels between the isochromene ring system and the methoxybenzene rings amount to 2.63 (3) and 0.79 (3) ° in the two crystallographically independent molecules

Related literature top

For general background, see: Barry (1964); Hill (1986); Canendo et al. (1997); Whyte et al. (1996). For related structures, see: Abid et al. (2006, 2008); Hathwar et al. (2007).

Experimental top

Homophthalic acid (1.3 g, 7.2 mmol) was added to p-methoxybenzoyl chloride (24.8 mmol) and was refluxed for 4 h at 473 K with stirring. The reaction mixture was extracted with ethyl acetate (3 times 100 ml), and an aqueous solution of sodium carbonate (5%, 200 ml) was added to remove the unreacted homophthalic acid. The organic layer was separated, concentrated and chromatographed on silica gel using petroleum ether (313–353 K fractions) as eluent to afford the title compound. Single crystals suitable for X-ray analysis were obtained by slow evaporation of an ethyl acetate solution.

Refinement top

All H atoms were positioned with idealized geometry and were refined using a riding model with C-H = 0.96 Å for CH3 and 0.93 Å for aromatic H atoms. The displacement parameters of the H atoms were constrained as Uiso(H) = 1.2Ueq (1.5Ueq for methyl) of the carrier atom.

Computing details top

Data collection: SMART (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (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) and CAMERON (Watkin et al., 1993); software used to prepare material for publication: PLATON (Spek, 2003).

Figures top
[Figure 1] Fig. 1. : Crystal structure of the title complex, showing 50% probability displacement ellipsoids and the atom-numbering scheme.
3-(4-Methoxyphenyl)-1H-isochromen-1-one top
Crystal data top
C16H12O3F(000) = 1056
Mr = 252.26Dx = 1.351 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 8668 reflections
a = 15.5949 (15) Åθ = 1.5–25.5°
b = 11.8464 (11) ŵ = 0.09 mm−1
c = 15.1824 (14) ÅT = 290 K
β = 117.838 (2)°Block, colourless
V = 2480.2 (4) Å30.28 × 0.14 × 0.08 mm
Z = 8
Data collection top
Bruker SMART CCD area-detector
diffractometer		4616 independent reflections
Radiation source: fine-focus sealed tube2795 reflections with I > 2σ(I)
graphiteRint = 0.038
φ and ω scansθmax = 25.5°, θmin = 1.5°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		h = −18→18
Tmin = 0.974, Tmax = 0.984k = −13→14
18262 measured reflectionsl = −18→18
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.045Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.109All H-atom parameters refined
S = 1.00 w = 1/[σ2(Fo2) + (0.0567P)2]
where P = (Fo2 + 2Fc2)/3
4616 reflections(Δ/σ)max = 0.001
345 parametersΔρmax = 0.14 e Å−3
0 restraintsΔρmin = −0.15 e Å−3
Crystal data top
C16H12O3V = 2480.2 (4) Å3
Mr = 252.26Z = 8
Monoclinic, P21/cMo Kα radiation
a = 15.5949 (15) ŵ = 0.09 mm−1
b = 11.8464 (11) ÅT = 290 K
c = 15.1824 (14) Å0.28 × 0.14 × 0.08 mm
β = 117.838 (2)°
Data collection top
Bruker SMART CCD area-detector
diffractometer		4616 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		2795 reflections with I > 2σ(I)
Tmin = 0.974, Tmax = 0.984Rint = 0.038
18262 measured reflectionsθmax = 25.5°
Refinement top
R[F2 > 2σ(F2)] = 0.045All H-atom parameters refined
wR(F2) = 0.109Δρmax = 0.14 e Å−3
S = 1.00Δρmin = −0.15 e Å−3
4616 reflectionsAbsolute structure: ?
345 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
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
xyzUiso*/Ueq
O10.46573 (12)0.71997 (11)1.12417 (10)0.0894 (5)
O20.41915 (8)0.88630 (10)1.05390 (8)0.0602 (3)
O30.35416 (9)1.40912 (10)1.06979 (10)0.0762 (4)
O40.03964 (12)0.71696 (11)0.15948 (11)0.0912 (5)
O50.08196 (8)0.88474 (10)0.13156 (8)0.0595 (3)
O60.13583 (9)1.40934 (10)0.20493 (9)0.0667 (4)
C10.43111 (14)0.77173 (16)1.04693 (14)0.0606 (5)
C20.38013 (11)0.95680 (14)0.97170 (12)0.0470 (4)
C30.35328 (11)0.91498 (14)0.88124 (12)0.0496 (4)
H30.32760.96340.82670.060*
C40.33679 (13)0.75059 (16)0.77199 (13)0.0600 (5)
H40.31210.79670.71590.072*
C50.34738 (13)0.63695 (17)0.76232 (14)0.0667 (5)
H50.33050.60690.69980.080*
C60.38271 (13)0.56691 (17)0.84417 (15)0.0690 (5)
H60.38850.48990.83640.083*
C70.40934 (13)0.61035 (16)0.93675 (14)0.0646 (5)
H70.43320.56300.99200.077*
C80.40056 (12)0.72591 (15)0.94798 (12)0.0503 (4)
C90.36294 (11)0.79755 (14)0.86563 (12)0.0475 (4)
C100.37489 (11)1.07382 (14)1.00008 (12)0.0467 (4)
C110.40524 (12)1.10565 (15)1.09812 (12)0.0551 (5)
H110.42971.05081.14760.066*
C120.40041 (13)1.21545 (16)1.12477 (13)0.0581 (5)
H120.42211.23401.19130.070*
C130.36364 (13)1.29749 (15)1.05313 (14)0.0552 (5)
C140.33210 (13)1.26874 (16)0.95395 (14)0.0629 (5)
H140.30671.32380.90470.076*
C150.33854 (13)1.15925 (15)0.92883 (13)0.0593 (5)
H150.31811.14140.86230.071*
C160.38761 (16)1.44487 (18)1.16989 (16)0.0882 (7)
H16A0.34741.41261.19560.132*
H16B0.38461.52571.17200.132*
H16C0.45341.42051.20960.132*
C170.07336 (13)0.77001 (16)0.11542 (13)0.0607 (5)
C180.11848 (11)0.95659 (14)0.08575 (11)0.0473 (4)
C190.14586 (11)0.91583 (14)0.02099 (12)0.0507 (4)
H190.16910.9653−0.01050.061*
C200.16909 (13)0.75191 (15)−0.06827 (14)0.0608 (5)
H200.19140.7993−0.10200.073*
C210.16469 (14)0.63793 (17)−0.08482 (14)0.0690 (5)
H210.18460.6087−0.12920.083*
C220.13085 (14)0.56579 (17)−0.03610 (14)0.0713 (6)
H220.12810.4884−0.04760.086*
C230.10135 (13)0.60905 (16)0.02928 (14)0.0664 (5)
H230.07850.56090.06200.080*
C240.10552 (12)0.72472 (15)0.04675 (12)0.0510 (4)
C250.14046 (11)0.79797 (14)−0.00148 (12)0.0477 (4)
C260.12307 (11)1.07354 (14)0.11878 (11)0.0471 (4)
C270.09425 (12)1.10360 (15)0.18924 (12)0.0575 (5)
H270.07231.04760.21670.069*
C280.09700 (13)1.21374 (15)0.22010 (13)0.0584 (5)
H280.07721.23120.26750.070*
C290.12929 (12)1.29732 (15)0.18019 (13)0.0517 (5)
C300.15888 (13)1.26986 (15)0.10993 (14)0.0621 (5)
H300.18111.32610.08290.074*
C310.15544 (13)1.16016 (15)0.08009 (13)0.0595 (5)
H310.17531.14320.03260.071*
C320.09712 (14)1.44297 (16)0.26951 (14)0.0770 (6)
H32A0.03171.41630.24340.115*
H32B0.09791.52380.27410.115*
H32C0.13581.41140.33450.115*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.1390 (14)0.0681 (9)0.0507 (8)0.0230 (9)0.0355 (9)0.0148 (7)
O20.0798 (9)0.0542 (8)0.0436 (7)0.0102 (6)0.0262 (6)0.0041 (6)
O30.0977 (11)0.0546 (9)0.0764 (10)0.0029 (7)0.0407 (8)−0.0108 (7)
O40.1466 (14)0.0660 (9)0.1082 (11)−0.0176 (9)0.0991 (11)−0.0002 (8)
O50.0785 (9)0.0537 (8)0.0633 (8)−0.0091 (6)0.0473 (7)−0.0027 (6)
O60.0808 (9)0.0559 (9)0.0723 (9)−0.0028 (7)0.0431 (7)−0.0091 (7)
C10.0737 (14)0.0577 (13)0.0510 (12)0.0102 (10)0.0295 (11)0.0063 (10)
C20.0468 (10)0.0532 (12)0.0422 (10)0.0010 (8)0.0216 (8)0.0069 (9)
C30.0550 (11)0.0513 (12)0.0421 (10)0.0013 (8)0.0222 (9)0.0070 (8)
C40.0612 (13)0.0649 (14)0.0481 (11)−0.0035 (10)0.0207 (10)−0.0031 (9)
C50.0642 (13)0.0718 (15)0.0568 (13)−0.0066 (11)0.0220 (11)−0.0176 (11)
C60.0734 (14)0.0573 (13)0.0729 (14)0.0018 (10)0.0313 (12)−0.0088 (11)
C70.0747 (14)0.0571 (14)0.0642 (13)0.0108 (10)0.0343 (11)0.0048 (10)
C80.0505 (11)0.0533 (12)0.0491 (11)0.0024 (9)0.0249 (9)0.0002 (9)
C90.0424 (10)0.0560 (12)0.0446 (11)−0.0041 (8)0.0208 (9)−0.0018 (9)
C100.0425 (10)0.0514 (11)0.0458 (10)−0.0009 (8)0.0203 (8)0.0010 (9)
C110.0613 (12)0.0582 (13)0.0469 (11)0.0034 (9)0.0261 (9)0.0023 (9)
C120.0663 (13)0.0611 (13)0.0477 (11)0.0006 (10)0.0271 (10)−0.0052 (10)
C130.0554 (12)0.0506 (13)0.0622 (13)−0.0029 (9)0.0296 (10)−0.0074 (10)
C140.0723 (14)0.0546 (13)0.0527 (12)0.0058 (10)0.0215 (10)0.0072 (10)
C150.0704 (13)0.0562 (13)0.0458 (11)0.0014 (10)0.0226 (10)−0.0015 (9)
C160.1071 (18)0.0744 (16)0.0891 (16)−0.0108 (13)0.0508 (14)−0.0317 (13)
C170.0746 (14)0.0555 (13)0.0621 (12)−0.0061 (10)0.0404 (11)0.0017 (10)
C180.0462 (10)0.0534 (12)0.0451 (10)−0.0041 (8)0.0236 (9)0.0041 (8)
C190.0535 (11)0.0532 (12)0.0514 (10)−0.0030 (8)0.0296 (9)0.0036 (9)
C200.0659 (13)0.0609 (14)0.0676 (12)−0.0032 (10)0.0413 (11)−0.0041 (10)
C210.0744 (14)0.0692 (14)0.0755 (14)0.0024 (11)0.0451 (12)−0.0095 (11)
C220.0824 (15)0.0551 (13)0.0783 (14)0.0029 (10)0.0391 (12)−0.0053 (11)
C230.0775 (14)0.0581 (14)0.0695 (13)−0.0065 (10)0.0393 (11)−0.0005 (10)
C240.0512 (11)0.0520 (12)0.0501 (10)−0.0006 (9)0.0237 (9)−0.0003 (9)
C250.0428 (10)0.0552 (12)0.0444 (10)0.0001 (8)0.0198 (9)0.0005 (9)
C260.0442 (10)0.0524 (11)0.0453 (10)−0.0005 (8)0.0213 (8)0.0017 (8)
C270.0646 (12)0.0618 (13)0.0562 (11)−0.0057 (9)0.0365 (10)0.0009 (9)
C280.0684 (13)0.0622 (13)0.0551 (11)−0.0019 (10)0.0377 (10)−0.0064 (10)
C290.0519 (11)0.0509 (12)0.0523 (11)0.0009 (9)0.0243 (9)−0.0022 (9)
C300.0728 (14)0.0543 (12)0.0749 (13)−0.0098 (10)0.0478 (12)−0.0024 (10)
C310.0731 (13)0.0595 (13)0.0634 (12)−0.0060 (10)0.0465 (11)−0.0055 (10)
C320.0862 (15)0.0708 (15)0.0819 (14)0.0036 (11)0.0459 (13)−0.0175 (11)
Geometric parameters (Å, °) top
O1—C11.2048 (19)C14—H140.9300
O2—C11.381 (2)C15—H150.9300
O2—C21.3842 (18)C16—H16A0.9600
O3—C131.3672 (19)C16—H16B0.9600
O3—C161.422 (2)C16—H16C0.9600
O4—C171.2032 (19)C17—C241.454 (2)
O5—C171.3765 (19)C18—C191.332 (2)
O5—C181.3794 (17)C18—C261.464 (2)
O6—C291.3700 (18)C19—C251.431 (2)
O6—C321.4272 (19)C19—H190.9300
C1—C81.453 (2)C20—C211.369 (2)
C2—C31.330 (2)C20—C251.396 (2)
C2—C101.465 (2)C20—H200.9300
C3—C91.431 (2)C21—C221.386 (3)
C3—H30.9300C21—H210.9300
C4—C51.373 (2)C22—C231.373 (2)
C4—C91.398 (2)C22—H220.9300
C4—H40.9300C23—C241.391 (2)
C5—C61.377 (2)C23—H230.9300
C5—H50.9300C24—C251.400 (2)
C6—C71.367 (2)C26—C271.387 (2)
C6—H60.9300C26—C311.389 (2)
C7—C81.394 (2)C27—C281.380 (2)
C7—H70.9300C27—H270.9300
C8—C91.394 (2)C28—C291.373 (2)
C10—C111.387 (2)C28—H280.9300
C10—C151.394 (2)C29—C301.384 (2)
C11—C121.375 (2)C30—C311.369 (2)
C11—H110.9300C30—H300.9300
C12—C131.369 (2)C31—H310.9300
C12—H120.9300C32—H32A0.9600
C13—C141.391 (2)C32—H32B0.9600
C14—C151.369 (2)C32—H32C0.9600
C1—O2—C2122.83 (14)H16A—C16—H16C109.5
C13—O3—C16117.94 (15)H16B—C16—H16C109.5
C17—O5—C18123.25 (13)O4—C17—O5116.63 (16)
C29—O6—C32117.23 (14)O4—C17—C24126.34 (18)
O1—C1—O2116.16 (16)O5—C17—C24117.03 (15)
O1—C1—C8126.72 (19)C19—C18—O5119.92 (15)
O2—C1—C8117.12 (16)C19—C18—C26127.93 (15)
C3—C2—O2120.00 (16)O5—C18—C26112.14 (13)
C3—C2—C10128.46 (16)C18—C19—C25121.77 (15)
O2—C2—C10111.54 (14)C18—C19—H19119.1
C2—C3—C9121.76 (16)C25—C19—H19119.1
C2—C3—H3119.1C21—C20—C25120.88 (17)
C9—C3—H3119.1C21—C20—H20119.6
C5—C4—C9120.42 (17)C25—C20—H20119.6
C5—C4—H4119.8C20—C21—C22120.60 (18)
C9—C4—H4119.8C20—C21—H21119.7
C4—C5—C6120.79 (18)C22—C21—H21119.7
C4—C5—H5119.6C23—C22—C21119.68 (19)
C6—C5—H5119.6C23—C22—H22120.2
C7—C6—C5120.17 (19)C21—C22—H22120.2
C7—C6—H6119.9C22—C23—C24120.24 (18)
C5—C6—H6119.9C22—C23—H23119.9
C6—C7—C8119.70 (18)C24—C23—H23119.9
C6—C7—H7120.2C23—C24—C25120.39 (16)
C8—C7—H7120.2C23—C24—C17119.93 (16)
C9—C8—C7120.83 (16)C25—C24—C17119.69 (17)
C9—C8—C1119.83 (17)C20—C25—C24118.20 (16)
C7—C8—C1119.34 (17)C20—C25—C19123.49 (15)
C8—C9—C4118.06 (16)C24—C25—C19118.31 (15)
C8—C9—C3118.44 (15)C27—C26—C31116.70 (16)
C4—C9—C3123.50 (16)C27—C26—C18121.72 (15)
C11—C10—C15116.53 (16)C31—C26—C18121.58 (14)
C11—C10—C2122.33 (16)C28—C27—C26122.33 (16)
C15—C10—C2121.13 (15)C28—C27—H27118.8
C12—C11—C10122.34 (17)C26—C27—H27118.8
C12—C11—H11118.8C29—C28—C27119.43 (16)
C10—C11—H11118.8C29—C28—H28120.3
C13—C12—C11119.88 (17)C27—C28—H28120.3
C13—C12—H12120.1O6—C29—C28124.97 (16)
C11—C12—H12120.1O6—C29—C30115.46 (16)
O3—C13—C12125.53 (17)C28—C29—C30119.57 (17)
O3—C13—C14115.03 (17)C31—C30—C29120.16 (17)
C12—C13—C14119.44 (17)C31—C30—H30119.9
C15—C14—C13119.93 (17)C29—C30—H30119.9
C15—C14—H14120.0C30—C31—C26121.81 (16)
C13—C14—H14120.0C30—C31—H31119.1
C14—C15—C10121.87 (16)C26—C31—H31119.1
C14—C15—H15119.1O6—C32—H32A109.5
C10—C15—H15119.1O6—C32—H32B109.5
O3—C16—H16A109.5H32A—C32—H32B109.5
O3—C16—H16B109.5O6—C32—H32C109.5
H16A—C16—H16B109.5H32A—C32—H32C109.5
O3—C16—H16C109.5H32B—C32—H32C109.5
C2—O2—C1—O1−179.82 (16)C18—O5—C17—O4−179.43 (17)
C2—O2—C1—C8−0.1 (2)C18—O5—C17—C240.4 (2)
C1—O2—C2—C3−0.7 (2)C17—O5—C18—C191.2 (2)
C1—O2—C2—C10179.49 (14)C17—O5—C18—C26−177.86 (14)
O2—C2—C3—C90.4 (2)O5—C18—C19—C25−1.3 (2)
C10—C2—C3—C9−179.86 (14)C26—C18—C19—C25177.58 (15)
C9—C4—C5—C60.8 (3)C25—C20—C21—C220.6 (3)
C4—C5—C6—C7−1.1 (3)C20—C21—C22—C230.1 (3)
C5—C6—C7—C80.0 (3)C21—C22—C23—C24−0.1 (3)
C6—C7—C8—C91.4 (3)C22—C23—C24—C25−0.5 (3)
C6—C7—C8—C1−178.60 (17)C22—C23—C24—C17179.46 (17)
O1—C1—C8—C9−179.05 (18)O4—C17—C24—C23−2.0 (3)
O2—C1—C8—C91.3 (2)O5—C17—C24—C23178.20 (15)
O1—C1—C8—C71.0 (3)O4—C17—C24—C25177.94 (19)
O2—C1—C8—C7−178.74 (15)O5—C17—C24—C25−1.9 (2)
C7—C8—C9—C4−1.7 (2)C21—C20—C25—C24−1.1 (3)
C1—C8—C9—C4178.31 (15)C21—C20—C25—C19178.23 (16)
C7—C8—C9—C3178.43 (14)C23—C24—C25—C201.1 (2)
C1—C8—C9—C3−1.6 (2)C17—C24—C25—C20−178.86 (15)
C5—C4—C9—C80.6 (2)C23—C24—C25—C19−178.30 (15)
C5—C4—C9—C3−179.54 (16)C17—C24—C25—C191.8 (2)
C2—C3—C9—C80.7 (2)C18—C19—C25—C20−179.51 (16)
C2—C3—C9—C4−179.12 (16)C18—C19—C25—C24−0.2 (2)
C3—C2—C10—C11179.61 (16)C19—C18—C26—C27−178.18 (17)
O2—C2—C10—C11−0.6 (2)O5—C18—C26—C270.8 (2)
C3—C2—C10—C15−0.3 (3)C19—C18—C26—C312.6 (3)
O2—C2—C10—C15179.50 (14)O5—C18—C26—C31−178.40 (15)
C15—C10—C11—C12−0.2 (2)C31—C26—C27—C280.1 (3)
C2—C10—C11—C12179.95 (15)C18—C26—C27—C28−179.13 (15)
C10—C11—C12—C130.7 (3)C26—C27—C28—C290.0 (3)
C16—O3—C13—C122.0 (3)C32—O6—C29—C28−6.6 (2)
C16—O3—C13—C14−178.23 (17)C32—O6—C29—C30173.92 (16)
C11—C12—C13—O3179.38 (15)C27—C28—C29—O6−179.69 (15)
C11—C12—C13—C14−0.4 (3)C27—C28—C29—C30−0.2 (3)
O3—C13—C14—C15179.79 (16)O6—C29—C30—C31179.88 (15)
C12—C13—C14—C15−0.4 (3)C28—C29—C30—C310.4 (3)
C13—C14—C15—C100.9 (3)C29—C30—C31—C26−0.3 (3)
C11—C10—C15—C14−0.7 (3)C27—C26—C31—C300.0 (3)
C2—C10—C15—C14179.22 (15)C18—C26—C31—C30179.28 (16)
Acknowledgements top

We thank the Department of Science and Technology, India, for use of the CCD facility set up under the IRHPADST program at IISc. We thank Professor T. N. Guru Row, IISc, Bangalore, for useful crystallographic discussions. FNK thanks the DST for Fast Track Proposal funding

references
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