3-Benzyl­isochroman-1-one

Tariq Mahmood Babar; Ghulam Qadeer; Nasim Hasan Rama; Muhammad Khawar Rauf; Wai-Yeung Wong

doi:10.1107/S1600536809004164

. 2009 Feb 11;65(Pt 3):o498. doi: 10.1107/S1600536809004164

3-Benzylisochroman-1-one

Tariq Mahmood Babar ^a, Ghulam Qadeer ^a,^*, Nasim Hasan Rama ^a,^‡, Muhammad Khawar Rauf ^a, Wai-Yeung Wong ^b,^§

PMCID: PMC2968672 PMID: 21582163

Abstract

In the molecule of the title compound, C₁₆H₁₄O₂, the aromatic rings are oriented at a dihedral angle of 78.49 (3)°. The heterocyclic ring adopts a twist conformation. In the crystal structure, intermolecular C—H⋯O hydrogen bonds link the molecules into chains along the c axis.

Related literature

For related structures, see: Schmalle et al. (1982 ▶); Schnebel et al. (2003 ▶). For a description of the Cambridge Structural Database, see: Allen (2002 ▶). For bond-length data, see: Allen et al. (1987 ▶). For puckering parameters, see: Cremer & Pople (1975 ▶).

Experimental

Crystal data

C₁₆H₁₄O₂
M _r = 238.27
Monoclinic,
a = 12.503 (5) Å
b = 8.0200 (9) Å
c = 12.892 (5) Å
β = 102.43 (2)°
V = 1262.4 (7) Å³
Z = 4
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 294 (2) K
0.32 × 0.26 × 0.21 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2001 ▶) T _min = 0.820, T _max = 0.983
7148 measured reflections
3024 independent reflections
2546 reflections with I > 2σ(I)
R _int = 0.021

Refinement

R[F ² > 2σ(F ²)] = 0.042
wR(F ²) = 0.136
S = 1.03
3024 reflections
164 parameters
H-atom parameters constrained
Δρ_max = 0.18 e Å⁻³
Δρ_min = −0.14 e Å⁻³

Data collection: SMART (Bruker, 2001 ▶); cell refinement: SAINT (Bruker, 2002 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ▶); software used to prepare material for publication: SHELXTL (Sheldrick, 2008 ▶).

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809004164/hk2615sup1.cif

e-65-0o498-sup1.cif^{(16.1KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809004164/hk2615Isup2.hkl

e-65-0o498-Isup2.hkl^{(148.4KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C9—H9B⋯O1ⁱ	0.97	2.53	3.2922 (18)	135

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Symmetry code: (i) Inline graphic .

Acknowledgments

The authors gratefully acknowledge the financial support of the Higher Education Commission, Islamabad, Pakistan.

supplementary crystallographic information

Comment

The title compound was prepared in order to evalute its potential as antibacterial and antifungal agents. The CCDC search (Allen, 2002) showed that the crystal structures of rac-exo-tricarbonyl-(h6-3-phenyl isochromanone) -chromium (Schnebel et al., 2003) and 3,4-dihydro-8-hydroxy-3-(4-hydroxy- phenyl)-isocoumarin (Schmalle et al., 1982) have been reported, which have close resemblance as far as isochromane and attached phenyl ring is considered. We report herein the synthesis and crystal structure of the title compound.

In the molecule of the title compound (Fig. 1), the bond lengths (Allen et al., 1987) and angles are within normal ranges. Rings A (C1-C6) and C (C11-C16) are, of course, planar, and they are oriented at a dihedral angle of 78.49 (3)°. Ring B (O2/C5-C9) is not planar, having total puckering amplitude, Q_T, of 2.420 (3) Å and twisted conformation [φ = 151.98 (3)° and θ = 88.50 (3)°] (Cremer & Pople, 1975).

In the crystal structure, intermolecular C-H···O hydrogen bonds (Table 1) link the molecules into chains along the c axis, in which they may be effective in the stabilization of the structure.

Experimental

As shown in Scheme 2, a mixture of homophthalic acid (1.98 g, 11.0 mmol) and 2-phenylacetyl chloride (7.08 g, 46 mmol) was heated under reflux for 6 h at 473 K. After concentration, the residue was chromatographed on silica gel column using petroleum ether (333–353 K) to give 3-benzyl-1H-isochromen-1-one. 2-(2-oxo-3-phenylpropyl) benzoic acid was obtained by refluxing a solution of 3-benzyl-1H-isochromen-1-one (4 g, 15.9 mmol) in ethanol (200 ml) and potassium hydroxide (5%,200 ml) for 6 h. NaBH4 (1.6 g) was added to a solution of 2-(2-oxo-3-phenylpropyl) benzoic acid (4.81 g, 17.8 mmol) in sodium hydroxide (1%, 180 ml) and the resulting solution was stirred overnight at room temperature. After being acidified with HCl, the whole mixture was extracted with dichloromethane (2 \ times 15 ml). Usual work-up gave crude racemic hydroxy-acid, 2-(2-hydroxy-3-phenylpropyl)benzoic acid, which was dissolved in acetic anhydride (5 ml) and heated under reflux for 2 h to get the title compound (yield; 73%, m.p. 605-606 K). The crude compound was purified by column chromatography on silica gel with petroleum ether and recrystallized in ethanol.