6-(Hex-5-en­yloxy)naphthalene-2-carb­oxy­lic acid

Md Lutfor Rahman; H T Srinivasa; Mashitah Mohd Yusoff; Huey Chong Kwong; Ching Kheng Quah

doi:10.1107/S1600536814010642

. 2014 May 24;70(Pt 6):o696–o697. doi: 10.1107/S1600536814010642

6-(Hex-5-enyloxy)naphthalene-2-carboxylic acid

Md Lutfor Rahman ^a,^*, H T Srinivasa ^b, Mashitah Mohd Yusoff ^a, Huey Chong Kwong ^c, Ching Kheng Quah ^d

PMCID: PMC4051067 PMID: 24940271

Abstract

The asymmetric unit of the title compound, C₁₇H₁₈O₃, comprises three independent molecules with similar geometries. In each molecule, the carbonyl group is twisted away from the napthalene ring system, making dihedral angles of 1.0 (2), 1.05 (19)° and 1.5 (2)°. The butene group in all three molecules are disordered over two sets of sites, with a refined occupancy ratio of 0.664 (6):0.336 (6). In the crystal, molecules are oriented with respect to their carbonyl groups, forming head-to-head dimers via O—H⋯O hydrogen bonds. Adjacent dimers are further interconnected by C—H⋯O hydrogen bonds into chains along the a-axis direction. The crystal structure is further stabilized by weak C—H⋯π interactions.

Related literature

For liquid crystal properties of carbonyl and naphthalene derivatives, see: Lee et al. (2001 ▶); Drzewinski (2013 ▶); Achalkumar et al. (2011 ▶). For naphthalene carboxylic acid derivatives, see: Rahman et al. (2013 ▶); Kozmik et al. (2005 ▶). For the synthesis of the title compound, see: Gopalakrishnan & Sadashiva (1998 ▶). For related structures, see: Fitzgerald & Gerkin (1993 ▶); Blackburn & Gerkin (1997 ▶); Lynch et al. (1998 ▶). For hydrogen-bond motifs, see: Bernstein et al. (1995 ▶). For bond-length data, see: Allen et al. (1987 ▶). graphic file with name e-70-0o696-scheme1.jpg

Experimental

Crystal data

C₁₇H₁₈O₃
M _r = 270.31
Triclinic,
a = 9.5018 (2) Å
b = 14.8695 (2) Å
c = 17.6757 (3) Å
α = 113.638 (1)°
β = 102.188 (1)°
γ = 93.127 (1)°
V = 2209.06 (7) Å³
Z = 6
Cu Kα radiation
μ = 0.67 mm⁻¹
T = 298 K
0.53 × 0.21 × 0.18 mm

Data collection

Bruker APEX DUO CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ▶) T _min = 0.719, T _max = 0.890
25536 measured reflections
6763 independent reflections
5768 reflections with I > 2σ(I)
R _int = 0.020

Refinement

R[F ² > 2σ(F ²)] = 0.045
wR(F ²) = 0.152
S = 1.06
6763 reflections
580 parameters
12 restraints
H-atom parameters constrained
Δρ_max = 0.23 e Å⁻³
Δρ_min = −0.17 e Å⁻³

Data collection: APEX2 (Bruker, 2009 ▶); cell refinement: SAINT (Bruker, 2009 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: Mercury (Macrae et al., 2006 ▶); software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ▶).

Supplementary Material

Crystal structure: contains datablock(s) I. DOI: 10.1107/S1600536814010642/kp2470sup1.cif

e-70-0o696-sup1.cif^{(55.9KB, cif)}

Structure factors: contains datablock(s) a. DOI: 10.1107/S1600536814010642/kp2470Isup2.hkl

e-70-0o696-Isup2.hkl^{(337.6KB, hkl)}

Click here for additional data file.^{(5.5KB, cml)}

Supporting information file. DOI: 10.1107/S1600536814010642/kp2470Isup3.cml

CCDC references: 1001958, 1001959

Additional supporting information: crystallographic information; 3D view; checkCIF report

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

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2A—H1⋯O1C ⁱ	0.97	1.65	2.6150 (16)	174
O2B—H2⋯O1B ⁱⁱ	0.85	1.80	2.6342 (15)	168
O2C—H3⋯O1A ⁱ	0.93	1.69	2.6133 (16)	177
C6A—H6AA⋯O1A ⁱⁱⁱ	0.93	2.50	3.3032 (19)	144
C6B—H6BA⋯O1B ⁱⁱⁱ	0.93	2.56	3.3666 (19)	145
C6C—H6CA⋯O1C ⁱⁱⁱ	0.93	2.56	3.3547 (18)	144
C5A—H5AA⋯O2C ^iv	0.93	2.59	3.421 (2)	149
C5B—H5BA⋯O2B ^v	0.93	2.65	3.520 (2)	156
C5C—H5CA⋯O2A ^iv	0.93	2.61	3.472 (2)	154
C17B—H17C⋯Cg1^vi	0.93	2.93	3.736 (5)	146

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Symmetry codes: (i) Inline graphic ; (ii) ; (iii) ; (iv) ; (v) ; (vi) .

Acknowledgments

This research was supported by a PRGS Research Grant (No. RDU 130803).

supplementary crystallographic information

1. Comment

The title compound is considered a potential candidate for material chemistry study comprising a polymerizable vinyl group at one end and a free carboxylic acid group at the other end of the molecule. In general, the free carboxylic acid group favours to form the hydrogen-bonded cyclic dimers in the liquid crystalline phases and most of the dimers exhibited enantiotropic liquid crystalline behavior (Lee et al. 2001). Considerable amount of work has been carried out in naphthalene derivatives to achieve application oriented SmC phase in low molar mass and polymeric liquid crystals with an azo/ester group (Drzewinski 2013; Achalkumar et al. 2011). These materials often studied in the view of their interesting optical properties, which enable applications such as optical switching, holography and optical storage devices (Rahman et al. 2013; Kozmik et al. 2005). This paper presents synthesis and crystal structure analysis of naphthalene based liquid crystalline precursor.

The asymmetry unit of the title compound (Fig. 1) comprises three crystallographically independent molecules (A, B and C) of similar geometries. The bonds lengths (Allen et al. 1987) and angles have normal values and comparable with the closely related structures (Fitzgerald & Gerkin 1993; Blackburn & Gerkin 1997; Lynch et al. 1998). In each molecule, the carbonyl group is almost coplanar with the attached naphthalene ring. The carbonyl group (O1—C1—O2) is slightly twisted away from the naphthalene ring system, with the dihedral angles of 1.00 (20)° in molecule A, 1.05 (19)° in molecule B and 1.50 (20)° in molecule C]. The butene groups which attached to atom C14 in each molecule (A, B and C) are disordered over two positions with a refined site-occupancy ratio of 0.695 (6): 0.305 (6).

In the crystal packing (Fig. 2), two adjacent molecules are linked into inversion dimers, forming R²₂(8) graph-set motifs (Bernstein et al. 1995) by a pair of intermolecular O2—H···O1 hydrogen bond (Table 1). These dimers are linked into chain along the a axis via intermolecular C5—H5···O2 and C6—H6···O1 hydrogen bonds. The crystal structure is further stabilized by a weak intermolecular C17B—H17C···Cg1 interaction (Cg1 is the centroid of the C4C—C9,C Table 1).

2. Experimental

The title compound is synthesized according to the literature (Gopalakrishnan & Sadashiva 1998). Pure and suitable single crystals were obtained on slow evaporation of ethyl alcohol at room temperature. The compound melts at 419 K to nematic phase, then it goes to isotropic state at 461 K. It returns to nematic phase at 486 K and then crystallizes at 410 K when it was cooled from isotropic state.